tellurium and Coronary-Artery-Disease

Topics: Cadmium; Coronary Artery Disease; Humans; Myocardial Perfusion Imaging; Tellurium; Tomography, Emission-Computed, Single-Photon

Cardiac PET-derived measurements of myocardial blood flow (MBF) and myocardial flow reserve (MFR) are proven robust indexes of the severity of coronary artery disease (CAD). They facilitate the diagnosis of diffuse epicardial and microvascular disease and are also of prognostic significance. However, low availability and high cost have limited their wide clinical implementation. Over the last 15 years, cadmium zinc telluride (CZT)-based detectors have been implemented into SPECT imaging devices. Myocardial perfusion scintigraphy can be performed faster and with less radiation exposure as compared with standard gamma cameras. Rapid dynamic SPECT studies with higher count rates can be performed. This technological breakthrough has renewed the interest in SPECT MBF assessment in patients with CAD. Currently, two cardiac-centered CZT gamma cameras are available commercially-Discovery NM530c and D-SPECT. They differ in parameters such as collimator design, number of detectors, sensitivity, spatial resolution and image reconstruction. A number of publications have focused on the feasibility of dynamic CZT SPECT and on the correlation with cardiac PET and invasive coronary angiography measurements of fractional flow reserve. Current study reviews the present status of MBF and MFR assessment with CZT SPECT. It also aims to provide an overview of specific issues related to acquisition, processing and interpretation of quantitative studies in patients with CAD.

Topics: Cadmium; Coronary Artery Disease; Fractional Flow Reserve, Myocardial; Humans; Myocardial Perfusion Imaging; Tellurium; Tomography, Emission-Computed, Single-Photon; Tomography, X-Ray Computed; Zinc

With the appearance of cadmium-zinc-telluride (CZT) cameras, dynamic myocardial perfusion imaging (MPI) has been introduced, but comparable data to other MPI modalities, such as quantitative coronary angiography (CAG) with fractional flow reserve (FFR) and positron emission tomography (PET), are lacking. This study aimed to evaluate the diagnostic accuracy of dynamic CZT single-photon emission tomography (SPECT) in coronary artery disease compared to quantitative CAG, FFR, and PET as reference.. Different databases were screened for eligible citations performing dynamic CZT-SPECT against CAG, FFR, or PET. PubMed, OvidSP (Medline), Web of Science, the Cochrane Library, and EMBASE were searched on the 5th of July 2020. Studies had to meet the following pre-established inclusion criteria: randomized controlled trials, retrospective trails or observational studies relevant for the diagnosis of coronary artery disease, and performing CZT-SPECT and within half a year the methodological references. Studies which considered coronary stenosis between 50% and 70% as significant based only on CAG were excluded. Data extracted were sensitivity, specificity, likelihood ratios, and diagnostic odds ratios. Quality was assessed with QUADAS-2 and statistical analysis was performed using a bivariate model.. Based on our criteria, a total of 9 studies containing 421 patients were included. For the assessment of CZT-SPECT, the diagnostic value pooled analysis with a bivariate model was calculated and yielded a sensitivity of 0.79 (% CI 0.73 to 0.85) and a specificity of 0.85 (95% CI 0.74 to 0.92). Diagnostic odds ratio (DOR) was 17.82 (95% CI 8.80 to 36.08, P < 0.001). Positive likelihood ratio (PLR) and negative likelihood ratio (NLR) were 3.86 (95% CI 2.76 to 5.38, P < 0.001) and 0.21 (95% CI 0.13 to 0.33, P < 0.001), respectively.. Based on the results of the current systematic review and meta-analysis, dynamic CZT-SPECT MPI demonstrated a good sensitivity and specificity to diagnose CAD as compared to the gold standards. However, due to the heterogeneity of the methodologies between the CZT-SPECT MPI studies and the relatively small number of included studies, it warrants further well-defined study protocols.

Topics: Cadmium; Coronary Angiography; Coronary Artery Disease; Fractional Flow Reserve, Myocardial; Humans; Myocardial Perfusion Imaging; Retrospective Studies; Tellurium; Tomography, Emission-Computed, Single-Photon; Tomography, X-Ray Computed; Zinc

We performed a meta-analysis to compare the diagnostic performance of conventional SPECT (C-SPECT) and cadmium-zinc-telluride (CZT)-SPECT systems in detecting angiographically proven coronary artery disease (CAD).. Studies published between January 2000 and February 2018 were identified by database search. We included studies assessing C-SPECT or CZT-SPECT as a diagnostic test to evaluate patients for the presence of CAD, defined as at least 50% diameter stenosis on invasive coronary angiography. A study was eligible regardless of whether patients were referred for suspected or known CAD.. We identified 40 eligible articles (25 C-SPECT and 15 CZT-SPECT studies) including 7334 patients (4997 in C-SPECT and 2337 in CZT-SPECT studies). The pooled sensitivity and specificity were 85% and 66% for C-SPECT and 89% and 69% for CZT-SPECT imaging studies. The area under the curve was slightly higher for CZT-SPECT (0.89) compared to C-SPECT (0.83); accordingly, the summary diagnostic OR was 17 for CZT-SPECT and 11 for C-SPECT. The accuracy of the two tests slightly differs between C-SPECT and CZT-SPECT (chi-square 11.28, P < .05). At meta-regression analysis, no significant association between both sensitivity and specificity and demographical and clinical variables considered was found for C-SPECT and CZT-SPECT studies.. C-SPECT and CZT-SPECT have good diagnostic performance in detecting angiographic proven CAD, with a slightly higher accuracy for CZT-SPECT. This result supports the use of the novel gamma cameras in clinical routine practices also considering the improvements in acquisition time and radiation exposure reduction.

Topics: Cadmium; Coronary Artery Disease; Gamma Cameras; Humans; Myocardial Perfusion Imaging; Quality Assurance, Health Care; Tellurium; Tomography, Emission-Computed, Single-Photon; Zinc

This study sought to summarize the evidence on stress myocardial perfusion imaging (MPI) using cadmium-zinc-telluride (CZT) technology for the diagnosis of obstructive coronary artery disease (CAD). The CZT cameras are newly introduced, and comparative data with the conventional Anger technology (Anger-MPI) are lacking.. The diagnostic accuracy of Anger-MPI for detection of angiographically significant CAD is well established; however, less evidence is available on the diagnostic accuracy of CZT-MPI.. Clinical studies comparing CZT-MPI and invasive coronary angiography were systematically searched and abstracted. Calculations of diagnostic accuracy, including sensitivity, specificity, likelihood ratios, and diagnostic odds ratio, were obtained with fixed and random effects, reporting point estimates and 95% confidence intervals.. Based on our search, a total of 16 studies (N = 2,092) were included. The sensitivity of CZT-MPI was 0.84 (95% confidence interval [CI]: 0.78 to 0.89), whereas the specificity of 0.69 (95% CI: 0.62 to 0.76) was significantly reduced. The positive likelihood ratio was 2.73 (95% CI: 2.21 to 3.39), the negative likelihood ratio was 0.24 (95% CI: 0.17 to 0.31), and the diagnostic odds ratio was 11.93 (95% CI: 7.84 to 17.42). At subgroup and meta-regression analyses, the diagnostic accuracy between D-SPECT and Discovery cameras was similar (p = 0.711) and not impacted upon by smaller sample size studies (p = 0.573).. CZT-MPI has satisfactory sensitivity for angiographically significant CAD, but its suboptimal specificity warrants further development and research.

Topics: Aged; Cadmium; Chi-Square Distribution; Coronary Angiography; Coronary Artery Disease; Coronary Circulation; Coronary Stenosis; Coronary Vessels; Equipment Design; Female; Humans; Likelihood Functions; Male; Middle Aged; Myocardial Perfusion Imaging; Odds Ratio; Predictive Value of Tests; Proportional Hazards Models; Reproducibility of Results; Tellurium; Zinc

The use of myocardial perfusion imaging has seen a tremendous growth during the last decade and has become the most commonly used non-invasive imaging tool for risk stratification in patients with suspected and known coronary artery disease. Adherence to radiation safety best practices varied significantly between laboratories but the possibility to use the new cameras in nuclear cardiology can reduce dramatically the radiation dose without losing accuracy. Moreover, the physical characteristics of ultrafast technology could be able to open new doors for the evaluation of old parameters, changing the impact of nuclear cardiology in the diagnostic strategies.

Topics: Cadmium; Cardiac-Gated Single-Photon Emission Computer-Assisted Tomography; Coronary Artery Disease; Female; Forecasting; Humans; Male; Myocardial Perfusion Imaging; Patient Safety; Radiation Dosage; Radiation Injuries; Radiometry; Radiopharmaceuticals; Risk Assessment; Safety Management; Tellurium; Zinc

The trade-off between resolution and count sensitivity dominates the performance of standard gamma cameras and dictates the need for relatively high doses of radioactivity of the used radiopharmaceuticals in order to limit image acquisition duration. The introduction of cadmium-zinc-telluride (CZT)-based cameras may overcome some of the limitations against conventional gamma cameras. CZT cameras used for the evaluation of myocardial perfusion have been shown to have a higher count sensitivity compared to conventional single photon emission computed tomography (SPECT) techniques. CZT image quality is further improved by the development of a dedicated three-dimensional iterative reconstruction algorithm, based on maximum likelihood expectation maximization (MLEM), which corrects for the loss in spatial resolution due to line response function of the collimator. All these innovations significantly reduce imaging time and result in a lower patient's radiation exposure compared with standard SPECT. To guide current and possible future users of the CZT technique for myocardial perfusion imaging, the Cardiovascular Committee of the European Association of Nuclear Medicine, starting from the experience of its members, has decided to examine the current literature regarding procedures and clinical data on CZT cameras. The committee hereby aims 1) to identify the main acquisitions protocols; 2) to evaluate the diagnostic and prognostic value of CZT derived myocardial perfusion, and finally 3) to determine the impact of CZT on radiation exposure.

Topics: Cadmium Compounds; Cardiac Imaging Techniques; Coronary Artery Disease; Equipment Design; Equipment Failure Analysis; Europe; Evidence-Based Medicine; Gamma Rays; Humans; Radiation Dosage; Radiation Exposure; Radionuclide Imaging; Reproducibility of Results; Sensitivity and Specificity; Tellurium; Zinc

Nuclear Cardiology for the past 40 years has distinguished itself in its ability to non-invasively assess regional myocardial blood flow and identify obstructive coronary disease. This has led to advances in managing the diagnosis, risk stratification, and prognostic assessment of cardiac patients. These advances have all been predicated on the collection of high quality nuclear image data. National and international professional societies have established guidelines for nuclear laboratories to maintain high quality nuclear cardiology services. In addition, laboratory accreditation has further advanced the goal of the establishing high quality standards for the provision of nuclear cardiology services. This article summarizes the principles of nuclear cardiology single photon emission computed tomography (SPECT) and positron emission tomography (PET) imaging and techniques for maintaining quality: from the calibration of imaging equipment to post processing techniques. It also will explore the quality considerations of newer technologies such as cadmium zinc telleride (CZT)-based SPECT systems and absolute blood flow measurement techniques using PET.

Topics: Algorithms; Artifacts; Blood Flow Velocity; Cadmium; Calibration; Coronary Artery Disease; Electrocardiography; Humans; Image Processing, Computer-Assisted; Motion; Positron-Emission Tomography; Quality Control; Scattering, Radiation; Software; Tellurium; Tomography, Emission-Computed, Single-Photon; Zinc

The purpose of this study was to investigate if a novel parameter, the stress-to-rest ratio of the signal-to-noise ratio (RSNR) obtained with a cadmium zinc telluride (CZT) SPECT scanner, could be used to distinguish triple-vessel disease (TVD) patients.

Topics: Aged; Cadmium Compounds; Contrast Media; Coronary Angiography; Coronary Artery Disease; Exercise Test; Female; Humans; Male; Middle Aged; Signal-To-Noise Ratio; Single Photon Emission Computed Tomography Computed Tomography; Tellurium; Zinc Compounds

Myocardial perfusion imaging (MPI) is well established in the diagnosis and workup of patients with known or suspected coronary artery disease (CAD); however, it can underestimate the extent of obstructive CAD. Quantification of myocardial perfusion reserve with PET can assist in the diagnosis of multivessel CAD. We evaluated the feasibility of dynamic tomographic SPECT imaging and quantification of a retention index to describe global and regional myocardial perfusion reserve using a dedicated solid-state cardiac camera.. Ninety-five consecutive patients (64 men and 31 women; median age, 67 y) underwent dynamic SPECT imaging with (99m)Tc-sestamibi at rest and at peak vasodilator stress, followed by standard gated MPI. The dynamic images were reconstructed into 60-70 frames, 3-6 s/frame, using ordered-subsets expectation maximization with 4 iterations and 32 subsets. Factor analysis was used to estimate blood-pool time-activity curves, used as input functions in a 2-compartment kinetic model. K1 values ((99m)Tc-sestamibi uptake) were calculated for the stress and rest images, and K2 values ((99m)Tc-sestamibi washout) were set to zero. Myocardial perfusion reserve (MPR) index was calculated as the ratio of the stress and rest K1 values. Standard MPI was evaluated semiquantitatively, and total perfusion deficit (TPD) of at least 5% was defined as abnormal.. Global MPR index was higher in patients with normal MPI (n = 51) than in patients with abnormal MPI (1.61 [interquartile range (IQR), 1.33-2.03] vs. 1.27 [IQR, 1.12-1.61], P = 0.0002). By multivariable regression analysis, global MPR index was associated with global stress TPD, age, and smoking. Regional MPR index was associated with the same variables and with regional stress TPD. Sixteen patients undergoing invasive coronary angiography had 20 vessels with stenosis of at least 50%. The MPR index was 1.11 (IQR, 1.01-1.21) versus 1.30 (IQR, 1.12-1.67) in territories supplied by obstructed and nonobstructed arteries, respectively (P = 0.02). MPR index showed a stepwise reduction with increasing extent of obstructive CAD (P = 0.02).. Dynamic tomographic imaging and quantification of a retention index describing global and regional perfusion reserve are feasible using a solid-state camera. Preliminary results show that the MPR index is lower in patients with perfusion defects and in regions supplied by obstructed coronary arteries. Further studies are needed to establish the clinical role of this technique as an aid to semiquantitative analysis of MPI.

Topics: Aged; Cadmium; Cohort Studies; Coronary Artery Disease; Feasibility Studies; Female; Humans; Male; Middle Aged; Myocardial Perfusion Imaging; Sensitivity and Specificity; Tellurium; Tomography, Emission-Computed, Single-Photon; Zinc

Obesity is a significant and independent risk factor for cardiovascular disease, and assessing ischaemia in obese patients is clinically important but sometimes difficult because of imaging artefacts. The aim of this study was to evaluate the feasibility and diagnostic accuracy of stress/rest imaging with a cadmium-zinc telluride (CZT) camera using a low-dose protocol in a series of consecutive obese patients referred for the evaluation of coronary artery disease.. We considered 148 consecutive obese patients (mean BMI 39 ± 7 kg/m(2)) with known or suspected coronary artery disease referred to our laboratory for stress/rest myocardial perfusion imaging. A subgroup of 103 of the 148 patients underwent invasive coronary angiography for clinical reasons. All patients underwent a single-day stress/rest low-dose ultrafast protocol. Patients were injected with (99m)Tc-tetrofosmin at a dose in the range 185-222 MBq during bicycle exercise or dipyridamole stress, and underwent the first scan with an acquisition time of 7 min starting 15 min after the end of the stress. The rest scan with an acquisition time of 6 min was started from 30 to 45 min after (99m)Tc-tetrofosmin injection at a dose in the range 370-444 MBq. Images were visually inspected, and the summed stress score (SSS) and summed rest score (SRS) were obtained.. Image quality was graded very good or excellent in all patients. Of the 103 patients who underwent coronary angiography, 12 (12 %), 26 (25 %) and 56 (54 %) showed one-, two- and three-vessel disease, and 9 showed normal coronary vessels. In the 103 patients submitted to coronary angiography, the mean SSS and SRS were 7 ± 6 and 2 ± 3, respectively. Semiquantitative regional and global SSS was a good discriminant of coronary artery disease and the area under the overall ROC curve was 0.848 (95 % CI 0.723-0.975).. In obese patients, a single-day stress/rest low-dose ultrafast protocol with a CZT camera is clinically feasible and provides high image quality.

Topics: Basal Metabolism; Cadmium; Coronary Angiography; Coronary Artery Disease; Fasting; Feasibility Studies; Female; Gamma Cameras; Humans; Male; Middle Aged; Obesity; Radiation Dosage; Sensitivity and Specificity; Stress, Physiological; Stroke Volume; Tellurium; Time Factors; Tomography, Emission-Computed, Single-Photon; Zinc

Evaluate the prediction of quantitative coronary angiography (QCA) values from MPI, by means of deep learning.. 546 patients (67% men) undergoing stress 99mTc-tetrofosmin MPI in a CZT camera in the upright and supine position were included (1092 MPIs). Patients were divided into two groups: ICA group included 271 patients who performed an ICA within 6 months of MPI and a control group with 275 patients with low pre-test probability for CAD and a normal MPI. QCA analyses were performed using radiologic software and verified by an expert reader. Left ventricular myocardium was segmented using clinical nuclear cardiology software and verified by an expert reader. A deep learning model was trained using a double cross-validation scheme such that all data could be used as test data as well.. Area under the receiver-operating characteristic curve for the prediction of QCA, with > 50% narrowing of the artery, by deep learning for the external test cohort: per patient 85% [95% confidence interval (CI) 84%-87%] and per vessel; LAD 74% (CI 72%-76%), RCA 85% (CI 83%-86%), LCx 81% (CI 78%-84%), and average 80% (CI 77%-83%).. Deep learning can predict the presence of different QCA percentages of coronary artery stenosis from MPIs.

Topics: Cadmium; Coronary Angiography; Coronary Artery Disease; Coronary Stenosis; Deep Learning; Female; Humans; Male; Myocardial Perfusion Imaging; Perfusion; Tellurium; Tomography, Emission-Computed, Single-Photon

Cadmium-zinc-telluride (CZT)-based detectors exhibit higher diagnostic sensitivity in myocardial perfusion imaging (MPI) than conventional Anger-MPI for detection of coronary artery disease (CAD); however, reduced specificity and diagnostic accuracy of CZT-MPI were observed. This study aims to compare these different camera systems and to examine the degree of inter-rater reproducibility among readers with varying experience in MPI.. 83 patients who underwent double stress/rest examinations using both a CZT and conventional SPECT cameras within one visit were included. Anonymized and randomized MPI-images were distributed to 15 international readers using a standardized questionnaire. Subsequent coronary angiography findings of ten patients served as a reference for analysis of sensitivity and specificity.. Image quality was significantly better in CZT-MPI with significantly lower breast attenuation (P < 0.05). CZT-MPI exhibited higher sensitivity than Anger-MPI (87.5% vs. 62.5%) and significantly reduced specificity (40% vs. 100%). Readers experienced with both camera systems had the highest inter-rater agreement indicating higher reproducibility (CZT 0.54 vs. conv. 0.49, P < 0.05).. Higher diagnostic sensitivity of CZT-MPI offers advantages in detection of CAD yet potentially of at the cost of reduced specificity, therefore it requires special training and a differentiated evaluation approach, especially for non-experienced readers with such camera systems.

Topics: Cadmium; Coronary Artery Disease; Humans; Myocardial Perfusion Imaging; Reproducibility of Results; Tellurium; Tomography, Emission-Computed, Single-Photon

Topics: Cadmium; Coronary Artery Disease; Coronary Circulation; Heart; Humans; Microcirculation; Myocardial Perfusion Imaging; Perfusion; Tellurium; Tomography, Emission-Computed, Single-Photon

Topics: Cadmium; Coronary Artery Disease; Humans; Myocardial Bridging; Myocardial Perfusion Imaging; Tellurium; Tomography, Emission-Computed, Single-Photon

Topics: Cadmium; Coronary Artery Disease; Humans; Myocardial Perfusion Imaging; Software; Tellurium; Tomography, Emission-Computed, Single-Photon; Zinc

Myocardial perfusion imaging (MPI) with single-photon emission computed tomography (SPECT) is a well-established diagnostic approach for patients with suspected or confirmed coronary artery disease (CAD). In the present century, nuclear cardiology has benefited immensely from advances in imaging instrumentation and technology. Dedicated cardiac SPECT cameras incorporating novel, highly efficient cadmium-zinc-telluride (CZT) detectors, collimators, and system designs have evolved as a result of the expansion of nuclear cardiology. A vast amount of evidence is emerging, demonstrating the new technology's advantages over the traditional gamma cameras. Myocardial perfusion imaging (MPI) using gamma-cameras with CZT detectors may be performed with the limited injected activity of radiotracer and recorded times. The use of CZT's dynamic acquisition of myocardial perfusion imaging in clinical practice may help cardiologists in detecting hemodynamically significant CAD. In this article, we present the current state of knowledge on cardiac CZT-SPECT scanners, a summary of the literature published on validation studies, radiation dose reduction, and dynamic acquisition, as well as a comparison of conventional myocardial perfusion imaging with invasive coronary angiography.

Topics: Cadmium; Coronary Artery Disease; Humans; Myocardial Perfusion Imaging; Technology; Tellurium; Tomography, Emission-Computed, Single-Photon; Zinc

We evaluated the performance of conventional (C) single-photon emission computed tomography (SPECT) and cadmium-zinc-telluride (CZT)-SPECT in a large cohort of patients with suspected or known coronary artery disease (CAD) and compared the diagnostic accuracy of the two systems using machine learning (ML) algorithms.. A total of 517 consecutive patients underwent stress myocardial perfusion imaging (MPI) by both C-SPECT and CZT-SPECT. In the overall population, an excellent correlation between stress MPI data and left ventricular (LV) functional parameters measured by C-SPECT and by CZT-SPECT was observed (all P < .001). ML analysis performed through the implementation of random forest (RF) and k-nearest neighbors (NN) algorithms proved that CZT-SPECT has greater accuracy than C-SPECT in detecting CAD. For both algorithms, the sensitivity of CZT-SPECT (96% for RF and 60% for k-NN) was greater than that of C-SPECT (88% for RF and 53% for k-NN).. MPI data and LV functional parameters obtained by CZT-SPECT are highly reproducible and provide good correlation with those obtained by C-SPECT. ML approach showed that the accuracy and sensitivity of CZT-SPECT is greater than C-SPECT in detecting CAD.

Topics: Cadmium; Coronary Artery Disease; Humans; Machine Learning; Myocardial Perfusion Imaging; Tellurium; Tomography, Emission-Computed, Single-Photon; Zinc

Breast attenuation artifacts occurring with upright cadmium-zinc-telluride (CZT) cardiac imaging systems have not been well characterized.. 216 consecutive patients with Single Photon Emission Computerized Tomography myocardial perfusion imaging and no angiographically significant obstructive coronary artery disease were identified. All upright and supine SPECT images as well as coronary angiograms were reviewed and analyzed in blinded fashion.. In women imaged upright, more visual false positive defects were noted in the inferior wall compared to the anterior wall (26 vs. 10 at rest, p = 0.006, and 33 vs. 13 at stress, p < 0.001). Visual inferior wall defects were more common in the upright than supine position at stress (33 vs. 23, p = 0.018) and rest (26 vs. 14, p = 0.011), and most apparent in non-obese women (13 vs. 8, at stress, p = 0.059 and 11 vs. 5, at rest, p = 0.014).. With upright CZT myocardial perfusion imaging, women often have visible inferior wall attenuation artifact defects, likely from pendant breast tissue. These inferior wall attenuation artifacts may be seen in non-obese female patients.

Topics: Artifacts; Cadmium; Coronary Angiography; Coronary Artery Disease; Female; Humans; Male; Myocardial Perfusion Imaging; Tellurium; Tomography, Emission-Computed, Single-Photon; Zinc

Topics: Cadmium; Coronary Artery Disease; Humans; Myocardial Perfusion Imaging; Tellurium; Tomography, Emission-Computed, Single-Photon

We compared the prognostic value of myocardial perfusion imaging (MPI) by conventional- (C-) single-photon emission computed tomography (SPECT) and cadmium-zinc-telluride- (CZT-) SPECT in a cohort of patients with suspected or known coronary artery disease (CAD) using machine learning (ML) algorithms. A total of 453 consecutive patients underwent stress MPI by both C-SPECT and CZT-SPECT. The outcome was a composite end point of all-cause death, cardiac death, nonfatal myocardial infarction, or coronary revascularization procedures whichever occurred first. ML analysis performed through the implementation of random forest (RF) and

Topics: Aged; Algorithms; Cadmium; Computational Biology; Coronary Artery Disease; Exercise Test; Female; Humans; Machine Learning; Male; Middle Aged; Myocardial Perfusion Imaging; Neural Networks, Computer; Prognosis; Tellurium; Tomography, Emission-Computed, Single-Photon; Zinc

We compared quantification of MBF and myocardial flow reserve (MFR) with a 99mTc-sestamibi CZT-SPECT to. SPECT MBF for thirty patients in the WATERDAY study was re-analyzed by QPET software with motion correction and optimal placement of the arterial input function.. Significant correlations were observed between global (r = 0.91, P < 0.001) and regional MBF (r = 0.86, P < 0.001) with SPECT compared to PET. Global MBF (rest 0.95 vs 1.05 ml/min/g, P = 0.07; stress 2.62 vs 2.68 mL/min/g, P = 0.17) and MFR (2.65 vs 2.75, P = 0.86) were similar between SPECT and PET. Rest (0.81 vs 0.98 mL/min/g, P = 0.03) and stress MBF (1.98 vs 2.61 mL/min/g, P = 0.01) in right coronary artery (RCA) were lower with SPECT compared to PET. However, MFR in the RCA territory was similar (2.54 vs 2.77, P = 0.21). The SPECT-PET RPC for global MBFs and MFR were 0.95 mL/min/g and 0.94, with inter-observer RPC of 0.59 mL/min/g and 0.74, respectively.. MBF and MFR derived from CZT-SPECT with motion correction and optimal placement of the arterial input function showed good agreement with

Topics: Aged; Algorithms; Cadmium; Coronary Artery Disease; Female; Fractional Flow Reserve, Myocardial; Humans; Male; Middle Aged; Motion; Myocardial Perfusion Imaging; Observer Variation; Oxygen Radioisotopes; Positron-Emission Tomography; Radiopharmaceuticals; Reproducibility of Results; Technetium Tc 99m Sestamibi; Tellurium; Tomography, Emission-Computed, Single-Photon; Water; Zinc

Limited data address the roles of gender, perfusion defect reversibility, and imaging position in interpretation of images acquired on an upright/supine cadmium-zinc-telluride (CZT) cardiac imaging system.. From a consecutive cohort of patients imaged on an upright/supine CZT camera, 260 patients with coronary angiograms were studied. Multivariable models identified gender as a significant effect modifier for imaging variables of CAD. For males, a supine summed stress score (SSS) ≥ 3 provided high accuracy (sensitivity 70.7%, specificity 72.2%), and highest contribution to multivariable models. In females, supine SSS ≥ 2 provided the best cut-off for defect size and severity (sensitivity 90%, specificity 35.9%), but specificity was improved substantially to 53.3% with decrease in sensitivity to 80% by also requiring quantitative identification of perfusion defect reversibility in the supine position. Eight variables, accurate for predicting coronary disease, were more accurate with supine than upright imaging.. Perfusion defect reversibility improved specificity in female patients for detection of coronary disease compared to perfusion defect size and extent alone. Supine images provided superior accuracy for detection of coronary disease compared to upright images.

Topics: Aged; Cadmium; Cohort Studies; Coronary Angiography; Coronary Artery Disease; Female; Gamma Cameras; Humans; Male; Middle Aged; Myocardial Perfusion Imaging; Patient Positioning; Sensitivity and Specificity; Sex Factors; Sitting Position; Supine Position; Tellurium; Tomography, Emission-Computed, Single-Photon; Zinc

Topics: Cadmium; Coronary Angiography; Coronary Artery Disease; Female; Gamma Cameras; Humans; Male; Myocardial Perfusion Imaging; Sensitivity and Specificity; Sex Factors; Tellurium; Tomography, Emission-Computed, Single-Photon; Zinc

Topics: Cadmium; Coronary Artery Disease; Fractional Flow Reserve, Myocardial; Humans; Positron-Emission Tomography; Tellurium; Tomography, Emission-Computed, Single-Photon; Zinc

Cadmium-zinc-telluride (CZT) SPECT allows the estimation of left ventricle myocardial volume (LVMV). We tested the clinical relevance of rest-stress LVMV changes (Δ LVMV) in detecting coronary artery disease (CAD, coronary stenosis > 70%), using CZT-SPECT.. We prospectively enrolled 512 consecutive patients with known or suspected CAD (mean age: 70.3 ± 9.2 years, 72% male) for stress-rest myocardial perfusion imaging (MPI, single-day stress-rest protocol). We quantified summed stress scores (SSS), summed rest scores, and summed difference scores, together with LVMV and ejection fraction (EF) after stress and at rest. All patients underwent coronary angiography within 30 days.. Two hundred seventy-two patients had CAD at coronary angiography. ΔLVMV ≤ 5 mL, corresponding to 6% of change from rest LVMV, was the best predictor of CAD (AUC = 0.831, 79% sensitivity, 82% specificity), irrespective of the stress protocol (dipyridamole or exercise stress) and independently of MPI-SSS, LV EF, and clinical history (P = 0.004). Integrated discrimination improvement (IDI) and net reclassification improvement (NRI) were significant for the addition of ΔLVMV ≤ 5 mL (IDI = 6.1%, P < 0.0001; NRI = 29.7%, P = 0.02) to MPI-SSS, whereas the other parameters were not.. The evaluation of ΔLVMV using CZT-SPECT can improve the diagnostic accuracy in predicting the presence of CAD when added to conventional MPI.

Topics: Aged; Cadmium; Cohort Studies; Coronary Angiography; Coronary Artery Disease; Exercise Test; Female; Humans; Male; Middle Aged; Myocardial Perfusion Imaging; Reproducibility of Results; Sensitivity and Specificity; Stroke Volume; Tellurium; Tomography, Emission-Computed, Single-Photon; Zinc

The global rest MBF was 0.76 ± 0.19 mL/min/gr by PET and 0.76 ± 0.24 by AC-CZT (P = NS) and 1.14 ± 0.4 by NAC-CZT (P < 0.001 vs PET and AC-CZT). Stress MBF was higher when measured by PET than AC-CZT (1.87 ± 0.45 vs 1.62 ± 0.68 mL/min/gr, P < 0.0008), but lower than NAC-CZT (2.36 ± 1.1, P < 0.0003). The MBF reserve ratio (MFR) was higher by PET than AC-CZT (2.52 ± 0.56 vs 2.22 ± 1 (P < 0.009) and NAC-CZT (2.18 ± 1.0, P < 0.004). Linear regression was better between PET (MFR and stress MBF) and AC-CZT than between PET and NAC-CZT. ROC curve analysis showed the significant ability of AC-CZT to predict MFR < 2 and stress MBF < 1.7 (AUC = 0.75 and 0.82 respectively) and to differentiate between normal and CAD patients (AUC = 0.747 and 0.892 for MFR and stress MBF, respectively).. Our data show a reasonable correlation between MBF and MFR measured by N

Topics: Adult; Aged; Aged, 80 and over; Ammonia; Cadmium; Coronary Artery Disease; Coronary Circulation; Female; Fractional Flow Reserve, Myocardial; Humans; Male; Middle Aged; Myocardial Perfusion Imaging; Nitrogen Radioisotopes; Organophosphorus Compounds; Organotechnetium Compounds; Positron Emission Tomography Computed Tomography; Predictive Value of Tests; Radiopharmaceuticals; ROC Curve; Tellurium; Tomography, Emission-Computed, Single-Photon; Zinc

Topics: Cadmium; Coronary Artery Disease; Exercise Test; Humans; Myocardial Perfusion Imaging; Reproducibility of Results; Sensitivity and Specificity; Stroke Volume; Tellurium; Tomography, Emission-Computed, Single-Photon; Zinc

Patient exposure to radiation during the management of coronary heart disease (CHD) can be reduced with more efficient technologies in nuclear medicine, such as the Cadmium-Zinc-Telluride (CZT) gamma-camera for myocardial perfusion imaging (MPI) studies. However, it has been suggested that CZT has lower specificity, which might lead to more downstream radiological procedures, particularly among obese individuals.. We evaluated 244 patients with suspected CHD who underwent CZT-SPECT and matched 1:1 according to sex, age, and body mass index (BMI) with those undergoing MPI study with the Anger gamma-camera (Anger-SPECT). The outcome was the total radiation exposure from the MPI study added to the radiation exposure from all subsequent cardiac examinations during a 90-day follow-up. The total radiation dose after 90 days was significantly lower in the CZT-SPECT group (6.4 ± 4.8 vs 9.5±4.9 mSv, P < .001). After adjusting for potential confounders, CZT-SPECT remained associated with lower total radiation dose, but it significantly attenuated among obese individuals (Beta coefficient - 3.73 ± 0.86 for BMI < 30 vs - 2.30 ± 0.92 for BMI ≥ 30 Kg/m. CZT-SPECT was associated with lower total radiation doses compared to Anger-SPECT, albeit this benefit may be attenuated in obese individuals.

Topics: Aged; Body Mass Index; Cadmium; Coronary Artery Disease; Female; Gamma Cameras; Humans; Male; Middle Aged; Myocardial Perfusion Imaging; Radiation Exposure; Tellurium; Tomography, Emission-Computed, Single-Photon; Zinc

Topics: Cadmium; Coronary Artery Disease; Dose-Response Relationship, Radiation; Gamma Cameras; Hormesis; Humans; Myocardial Perfusion Imaging; Radiation Exposure; Risk Assessment; Tellurium; Tomography, Emission-Computed, Single-Photon; Zinc

The goal of this study is to explore and evaluate the diagnostic values of myocardial blood flow (MBF), myocardial flow reserve (MFR) and relative flow reserve (RFR) obtained with low-dose dynamic CZT SPECT for patients with suspected or known coronary artery disease (CAD). Fifty-seven consecutive patients who underwent low-dose dynamic CZT SPECT and CAG were enrolled. MBF, MFR and RFR were calculated on the vessel level with dedicated quantitative software, and the difference and correlation of each parameter was compared according to the reference standard of stenosis ≥ 50% or ≥ 75% on CAG, respectively. ROC curves were made by stress MBF (sMBF), rest MBF (rMBF), MFR and RFR. The optimal cut-off values and corresponding diagnostic efficacy were obtained and compared with each other. Results indicated that when stenosis ≥ 50% or ≥ 75% on CAG was used as the reference standard at the vessel level, there was no statistically significant difference in rMBF between the negative group and the positive group (P > 0.05), and the sMBF and MFR in positive groups were significantly lower than that in the negative group (all P < 0.05). There was a moderate to significant correlation between sMBF and MFR, sMBF and RFR, MFR and RFR (all P < 0.0001). These results indicate that low-dose dynamic CZT SPECT imaging can easily obtain the sMBF, MFR and RFR, and there is a good correlation among the three parameters, which has a certain diagnostic value for patients with suspected or known CAD, and is a useful supplement to the conventional qualitative or semi-quantitative diagnostic methods.

Topics: Aged; Cadmium; Coronary Artery Disease; Coronary Circulation; Coronary Stenosis; Coronary Vessels; Female; Humans; Male; Middle Aged; Myocardial Perfusion Imaging; Predictive Value of Tests; Radiopharmaceuticals; Reproducibility of Results; Technetium Tc 99m Sestamibi; Tellurium; Tomography, Emission-Computed, Single-Photon; Zinc

To define the diagnostic power of absolute myocardial blood flow (MBF) evaluation on dynamic CZT imaging in intermediate risk patients in comparison with invasive coronary angiography (ICA) and fractional flow reserve (FFR).. Twenty-three stable CAD patients underwent one-day dynamic rest-stress 99mTc-Sestamibi myocardial perfusion imaging by CZT camera. Stress and rest MBF values were calculated semi-automatically using a net retention model by Leppo. Coronary flow reserve (CFR) and flow difference (FD) [MBF stress - MBF rest] were also estimated. A total of 28 vessels were functionally quantified with FFR: 19 (68%) vessels with a stenosis ≥ 70% and 9 (32%) with < 70% stenotic lesions.. The mean global MBFs at rest and during stress were 0.36 (IQR 0.33-0.54) mL/min/g and 0.67 (IQR 0.55-0.81) mL/min/g, respectively, with an average CFR of 1.80 (IQR 1.35-2.24). Moderate correlations between stenosis severity and FFR (r = 0.45; P = .01), stress MBF (r = -0.46; P = .01) and FD (r = -0.37; P = .04) were detected. FFR abnormalities were best predicted by absolute stress MBF, CFR and FD with values of ≤ 0.54 mL/min/g (sensitivity 61.5%; specificity 93.3%), ≤ 1.48 (sensitivity 69.2%; specificity 93.3%) and ≤ 0.18 mL/min/g (sensitivity 69.2%; specificity 100%), respectively.. The values of stress MBF, CFR and FD obtained through dynamic CZT acquisitions compare well with invasive FFR. The clinical use of dynamic acquisition of myocardial perfusion imaging by CZT may help cardiologist in the detection of hemodynamically significant CAD.

Topics: Aged; Cadmium; Coronary Angiography; Coronary Artery Disease; Coronary Circulation; Exercise Test; Female; Fractional Flow Reserve, Myocardial; Humans; Male; Middle Aged; Myocardial Perfusion Imaging; Predictive Value of Tests; Radiopharmaceuticals; ROC Curve; Severity of Illness Index; Technetium Tc 99m Sestamibi; Tellurium; Tomography, Emission-Computed, Single-Photon; Zinc

Previous studies have suggested using gamma cameras with cadmium-zinc-telluride (CZT) detectors to quantify myocardial blood flow (MBF) and flow reserve (MFR). In this study, we aimed to evaluate the feasibility and accuracy of MFR quantification using a CZT camera compared to coronary angiography.. Forty-one participants referred for coronary angiography underwent a rest/stress one-day myocardial perfusion imaging protocol using a CZT gamma camera. Rest and stress dynamic phases were followed by acquisition of traditional perfusion images and time-activity curves were generated. Angiographic and perfusion results were compared to MFR.. Patients with abnormal perfusion presented reduced MFR (2.01 [1.48-2.77] vs. 2.94 [2.38-3.64], P = 0.002), and reduced stress MBF. Patients with high-risk CAD had lower global MFR compared to patients without obstructive disease (1.99 [1.22-2.84] vs. 2.89 [2.22-3.58], P = 0.026). Obstructed vessels showed lower regional MFR when compared to non-obstructed (1.81 [1.19-2.67] vs. 2.75 [2.13-3.42], P < 0.001). A regional MFR of 2.2 provided a sensitivity of 63.2% and specificity of 74.1% to identify an obstructive lesion in the corresponding artery.. In patients undergoing invasive coronary angiography for the evaluation of CAD, quantifying MBF and MFR in a CZT gamma camera is feasible and reflects underlying disease. In these patients, reduced regional MFR suggests the presence of obstructive lesion(s).

Topics: Aged; Algorithms; Angiography; Animals; Cadmium; Coronary Angiography; Coronary Artery Disease; Female; Fractional Flow Reserve, Myocardial; Gamma Cameras; Humans; Image Processing, Computer-Assisted; Male; Middle Aged; Myocardial Perfusion Imaging; Perfusion; Prospective Studies; Reproducibility of Results; Risk; ROC Curve; Sensitivity and Specificity; Tellurium; Zinc

Breast attenuation may impact the diagnostic accuracy of stress myocardial perfusion imaging (MPI) with single-photon emission computed tomography (SPECT). We compared the performance of conventional (C)-SPECT and cadmium-zinc-telluride (CZT)-SPECT systems in women with low-intermediate likelihood of coronary artery disease (CAD).. A total of 109 consecutive women underwent stress-optional rest MPI by both C-SPECT and CZT-SPECT. In the overall study population, a weak albeit significant correlation between total perfusion defect (TPD) measured by C-SPECT and CZT-SPECT was observed (r = 0.38, P < .001) and at Bland-Altman analysis the mean difference in TPD (C-SPECT minus CZT-SPECT) was 2.40% (P < .001). Overall concordance of semi-quantitative diagnostic performance between C-SPECT and CZT-SPECT was observed in 52 (48%) women with a κ value of 0.09. Normalcy rate was significantly higher using CZT-SPECT compared to C-SPECT (P < .001). Machine learning analysis performed through the implementation of J48 algorithm proved that CZT-SPECT has higher sensitivity, specificity, and accuracy than C-SPECT.. In women with low-intermediate likelihood of CAD, there is a poor concordance of diagnostic performance between C-SPECT and CZT-SPECT, and CZT-SPECT allows better normalcy rate detection compared to C-SPECT.

Topics: Aged; Cadmium; Coronary Angiography; Coronary Artery Disease; Electrocardiography; Exercise Test; Female; Gamma Cameras; Humans; Image Processing, Computer-Assisted; Machine Learning; Middle Aged; Myocardial Perfusion Imaging; Perfusion; Reproducibility of Results; Risk Factors; Semiconductors; Software; Tellurium; Tomography, Emission-Computed, Single-Photon; Zinc

Topics: Cadmium; Coronary Angiography; Coronary Artery Disease; Fractional Flow Reserve, Myocardial; Heart; Hemodynamics; Humans; Motion; Myocardial Perfusion Imaging; Perfusion; Positron Emission Tomography Computed Tomography; Prognosis; Software; Tellurium; Zinc

Relative myocardial perfusion imaging can misdiagnose "balanced" ischemia caused by coronary artery disease (CAD). We assessed the feasibility of myocardial blood flow (MBF) and myocardial perfusion reserve (MPR) using dynamic single-photon emission computed tomography (SPECT) with a cadmium-zinc-telluride (CZT) camera for estimating underlying CAD in patients with normal stress myocardial perfusion SPECT (MPS).. 125 patients with normal stress MPS (summed stress score ≤3) were enrolled. All patients underwent coronary angiography (CAG) and stress/rest. MPR was 2.85 in patients with no CAD, 2.47 with 1-, 1.98 with 2-, and 1.76 with 3-vessel CAD. The patient's age, morbidity of diabetes mellitus (DM), chronic kidney disease (CKD), stress MBF, and MPR were significantly associated with the presence of CAD (age, p=0.02; DM, p=0.005; CKD, p=0.005; creatinine level, p= 0.012, stress MBF, p=0.019, and MPR, p<0.001). Independent predictors in the multivariate regression analysis were as follows: DM, p=0.011, CKD, p=0.028, and MPR, p<0.001. The combined index was calculated from three independent predictors. Area under the receiver operating characteristic curve was 0.75 for MPR and 0.81 for the combined index. To identify CAD, sensitivity, and specificity for MPR were 77% and 66%, and for the combined index they were 79% and 66%, respectively.. Quantification of MPR and MBF using dynamic SPECT with a CZT camera can be useful to identify balanced ischemia caused by occult CAD in patients with normal stress MPS findings.

Topics: Aged; Aged, 80 and over; Cadmium; Coronary Angiography; Coronary Artery Disease; Coronary Circulation; Female; Humans; Male; Middle Aged; Myocardial Perfusion Imaging; Tellurium; Tomography, Emission-Computed, Single-Photon; Zinc

Topics: Blood Flow Velocity; Cadmium; Constriction, Pathologic; Coronary Artery Disease; Coronary Circulation; Coronary Vessels; Female; Heart; Humans; Image Processing, Computer-Assisted; Middle Aged; Myocardium; Tellurium; Tomography, Emission-Computed, Single-Photon; Zinc

Previous studies have demonstrated left ventricular mechanical dyssynchrony (LVMD) in patients with severe coronary artery disease (CAD) with ≥ 70% stenosis. The aim of this study was to evaluate the clinical usefulness of stress/rest LVMD in the diagnosis of CAD with ≥ 50% stenosis using dipyridamole thallium-201 (Tl-201) myocardial perfusion imaging (MPI) with a cadmium-zinc-telluride camera.. A total of 476 patients without known CAD who underwent dipyridamole Tl-201 MPI and coronary angiography within 6 months were retrospectively reviewed. LVMD parameters including phase standard deviation and phase histogram bandwidth, phase skewness and phase kurtosis, as well as myocardial perfusion and myocardial stunning were assessed in post-stress and rest MPI. Relationships between the presence of CAD on coronary angiography and single photon emission computerized tomography (SPECT) parameters were evaluated. The presence of perfusion abnormalities was the best diagnostic tool in detecting CAD. Although less left ventricular synchrony was observed post-stress in the CAD group compared to the non-CAD group, no significant dyssynchrony was noted.. The addition of phase analysis to help diagnose CAD in Tl-201-gated SPECT with dipyridamole stress may have limited value in patients with CAD with ≥ 50% stenosis.

Topics: Aged; Cadmium; Cardiac-Gated Single-Photon Emission Computer-Assisted Tomography; Coronary Angiography; Coronary Artery Disease; Dipyridamole; Female; Humans; Male; Middle Aged; Myocardial Perfusion Imaging; Myocardial Stunning; Tellurium; Thallium Radioisotopes; Vasodilator Agents; Ventricular Function; Zinc

Topics: Cadmium; Coronary Artery Disease; Dipyridamole; Humans; Myocardial Perfusion Imaging; Tellurium; Thallium Radioisotopes; Zinc

The aim of this study was to compare the diagnostic performances for the detection of myocardial ischemia of 82-Rb-PET-MPS and 99m-Tc-SPECT-MPS in overweight individuals and women.. Men with BMI ≥ 25 and women referred for MPS were considered for inclusion. All individuals underwent 99m-Tc-SPECT-MPS with CZT cameras and 82-Rb-PET-MPS in 3D-mode. Individuals with at least one positive MPS were referred for coronary angiography (CA) with FFR measurements. A criterion for positivity was a composite endpoint including significant stenosis on CA or, in the absence of CA, the occurrence of acute coronary event during the following year. 313 patients (46% women) with mean BMI of 31.8 ± 6.5 were included. Sensitivity for the detection of myocardial ischemia was higher with 82-Rb-PET-MPS compared with 99m-Tc-SPECT-MPS (85% vs. 57%, P < .05); specificity was equally high with both imaging techniques (93% vs. 94%, P > .05). 82-Rb-PET allowed for a more accurate detection of patients with a high-risk coronary artery disease (HR-CAD) than 99m-Tc-SPECT-MPS (AUC = 0.86 vs. 0.75, respectively; P = .04).. In women and overweight individuals, 82-Rb-PET-MPS provides higher sensitivity for the detection of myocardial ischemia than 99m-Tc-SPECT-MPS thanks to a better image quality and an improved detection of HR-CAD.

Topics: Aged; Area Under Curve; Body Mass Index; Cadmium; Coronary Artery Disease; Female; Humans; Image Processing, Computer-Assisted; Male; Middle Aged; Myocardial Ischemia; Overweight; Positron-Emission Tomography; Reproducibility of Results; Risk Factors; Rubidium; Sensitivity and Specificity; Tellurium; Tomography, Emission-Computed, Single-Photon; Zinc

Recently, the feasibility of myocardial blood flow (MBF) quantitation using rapid-rotating gantry (RRG) and cadmium-zinc-telluride (CZT) SPECT cameras has been demonstrated. We compared MBF quantitation using these two camera systems.. Twenty patients with congestive heart failure (CHF) and 20 patients without CHF (non-CHF) were included. On two consecutive days, dynamic SPECT imaging was performed after a bolus injection of 20 mCi of. In both patient groups, there was no significant difference between resting MBF values measured with RRG-SPECT and CZT-SPECT systems (P = 0.06, P = 0.2 respectively). For CHF patients, linear regression (LR) was y(RRG) = 1.0412x (CZT) (r = 0.97) with a small systemic difference (Δ = 0.03 mL·min. Physical corrections along with other image corrections can provide comparable MBF quantitations in both CHF and non-CHF patients, regardless of the type of SPECT systems used.

Topics: Adult; Aged; Cadmium; Coronary Artery Disease; Echocardiography; Female; Heart; Heart Failure; Heart Ventricles; Hemodynamics; Humans; Image Processing, Computer-Assisted; Kinetics; Linear Models; Male; Middle Aged; Myocardial Perfusion Imaging; Reproducibility of Results; Technetium Tc 99m Sestamibi; Tellurium; Tomography, Emission-Computed, Single-Photon; Zinc

Data regarding cardiac cadmium-zinc-telluride (CZT)-specific augmented databases and their impact on CT-based attenuation correction (AC) perfusion scores in myocardial perfusion imaging (MPI) were obtained on a multiple-pinhole CZT SPECT/CT.. Summed stress (SSS) and rest scores (SRS) were measured using automated software in three independent patient groups: group 1 (n = 80) underwent MPI on both CZT and conventional sodium iodide (NaI) devices, group 2 (n = 80) with low coronary artery disease likelihood and normal MPI provided reference CZT databases; and group 3 (n = 152) served to compare AC and non-AC (NAC) scores on CZT. Group 1 CZT and NaI scores gave a significant 1:1 linear correlation for CZT scores referenced to the custom database vs NaI scores referenced to the default database, but these were not concordant when CZT scores were referenced to the default database. AC significantly decreased average SSS and SRS in men vs NAC, 4.29 ± 6.30 vs 5.37 ± 7.26 (P < 0.001) and 2.37 ± 4.72 vs 3.13 ± 5.85 (P < 0.001), but not in women, 2.28 ± 3.42 vs 2.28 ± 3.08 (p NS) and 0.46 ± 1.51 vs 0.61 ± 1.86, (p NS), respectively.. Specifically designed databases for solid-state CZT cardiac SPECT provide accurate quantitation of perfusion scores concordant with those previously validated for conventional SPECT. AC and NAC CZT scores differed significantly, especially in men.

Topics: Aged; Cadmium; Coronary Artery Disease; Databases, Factual; Female; Gamma Cameras; Heart; Humans; Male; Middle Aged; Myocardial Perfusion Imaging; Perfusion; Signal Processing, Computer-Assisted; Single Photon Emission Computed Tomography Computed Tomography; Software; Tellurium; Zinc

We validated a 1-day myocardial perfusion imaging (MPI) protocol using an ultra low-dose(ULD) equal for stress and rest on a cadmium zinc telluride (CZT).. Fifty-six patients underwent a 1-day MPI protocol using a standard (SD) 99mTc-tetrofosmin dose at stress (320 MBq) and rest (960 MBq) with 5 min acquisition time each (SD). Within 2 weeks MPI was repeated using ULD 99mTc-tetrofosmin equal for stress and rest (160 MBq) with 15 min acquisition time each (ULD). All scans were performed on a CZT camera (DNM 570c, GE Healthcare). Background subtraction was applied on the rest MPI of the ULD using P-mod software. Presence and extent of perfusion defect were analysed. Pearson's correlation was used to compare ejection fraction (EF), end diastolic volume (EDV), and end systolic volume (ESV) between both protocols. SD revealed ischaemia in 23, scar in 3, and an equivocal finding in 1 patient, while normal findings were documented in 29 patients. ULD resulted in the following findings: ischaemia 23, scar 3, and 30 normal scans. Congruence of SD and ULD was 22/23 for ischaemia, 3/3 for scar, and 29/29 in normal patients; one patient with ischaemia in SD was classified as scar in ULD. Overall agreement of ULD with SD was 98%. The mean extent of defect was comparable between SD and ULD for the stress (10% vs. 11%, respectively, P = NS) and rest studies (5% vs. 7%, respectively, P = NS). An excellent correlation between SD and ULD was found for EF (r = 0.93), EDV (r = 0.95), and ESV (r = 0.97).. CZT cameras may enable reliable MPI scanning in patients with known or suspected coronary artery disease using protocols with about a factor 4-decrease in radiation dose exposure compared with traditional protocols.

Topics: Aged; Aged, 80 and over; Cadmium; Cardiac-Gated Imaging Techniques; Coronary Artery Disease; Exercise Test; Female; Gamma Cameras; Humans; Male; Middle Aged; Myocardial Perfusion Imaging; Organophosphorus Compounds; Organotechnetium Compounds; Prospective Studies; Radiographic Image Interpretation, Computer-Assisted; Radiopharmaceuticals; Rest; Tellurium; Tomography, Emission-Computed, Single-Photon; Tomography, X-Ray Computed; Zinc

To evaluate gender-related differences in diagnostic accuracy of cadmium‑zinc-telluride (CZT) myocardial perfusion imaging in detecting single- and multi-vessel coronary artery disease (CAD).. We prospectively enrolled 1161 consecutive patients with known or suspected coronary artery disease (288, 25% women and 873, 75% men) who had been referred to our laboratory for stress-rest myocardial perfusion imaging (single-day stress-rest protocol, mean radiation dose: 4 mSv). All patients underwent coronary angiography within 30 days; significant CAD was defined in the presence of a coronary stenosis >70%. Summed stress scores (SSS), summed rest scores (SRS) and summed difference scores (SDS) were obtained. Image quality was graded "good" or better in >90% of patients.. On coronary angiography, left main trunk, left anterior descending artery, left circumflex artery and right coronary artery obstructive stenosis were seen in 13, 486, 393 and 499 patients, respectively. Global SSS was the best predictor of CAD in women (AUC = 0.866, 81% sensitivity and 79% specificity) and in men (AUC = 0.871, 76% sensitivity and 84% specificity). Interestingly, its accuracy was maintained also in patients with two-vessel (women: AUC = 0.842, p < 0.001; men: AUC 0.839, p < 0.001) or three-vessel disease (women: AUC = 0.800, p < 0.001; men: AUC 0.804, p < 0.001). There was no gender-related difference in terms of diagnostic accuracy.. Evaluation of multivessel disease can be obtained by CZT camera in men as well as in women, with high accuracy at a lower radiation exposure.

Topics: Aged; Cadmium; Coronary Artery Disease; Coronary Vessels; Female; Follow-Up Studies; Humans; Incidence; Italy; Male; Myocardial Perfusion Imaging; Prospective Studies; Reproducibility of Results; Sex Factors; Tellurium; Tomography, Emission-Computed, Single-Photon; Zinc

Dedicated cadmium-zinc-telluride cardiac cameras have been shown to provide accurate measurements of absolute myocardial blood flow and flow reserve when PET is not available. We report the case of a 66-year-old woman who underwent 1-day stress/rest myocardial perfusion imaging (MPI) for coronary artery disease (CAD) screening. Relative MPI analysis was normal, whereas low-dose CT showed high calcium score. Myocardial blood flow and flow reserve were strongly impaired in all territories. Coronary angiography confirmed extended CAD. Flow parameters derived from cadmium-zinc-telluride SPECT MPI acquisition and calcium scoring can improve diagnostic accuracy and confidence of CAD.

Topics: Aged; Cadmium; Calcium; Coronary Angiography; Coronary Artery Disease; Coronary Circulation; Female; Humans; Myocardial Perfusion Imaging; Tellurium; Tomography, Emission-Computed, Single-Photon; Zinc

We previously validated the use of a data-driven cardiac respiratory-motion (RM) correction method (REGAT) applicable to CZT SPECT myocardial perfusion imaging (MPI). In this study, we adapted the same process used with REGAT for RM to generate data-driven cardiac contraction triggers and corresponding cardiac contraction-gated SPECT studies (GSPECT-DD). We aimed to study its feasibility and compare its performances to GSPECT studies generated with ECG monitor-based triggers (GSPECT-ECG).. We found almost perfect agreement between cardiac contraction triggers generated with data-driven and ECG monitor-based methods. As compared to GSPECT-ECG, GSPECT-DD provided comparable and well-correlated LV global systolic function parameters and similar cine image quality at both stress and rest.. Data-driven cardiac contraction gating using REGAT is feasible with low-dose and high-dose MPI CZT SPECT. It provides GSPECT-DD studies comparable to GSPECT-ECG.

Topics: Aged; Cadmium; Cardiac-Gated Single-Photon Emission Computer-Assisted Tomography; Coronary Artery Disease; Electrocardiography; Exercise Test; Feasibility Studies; Female; Heart; Heart Ventricles; Humans; Image Processing, Computer-Assisted; Male; Middle Aged; Motion; Myocardial Perfusion Imaging; Nuclear Medicine; Organophosphorus Compounds; Organotechnetium Compounds; Prospective Studies; Radiopharmaceuticals; Respiration; Tellurium; Ventricular Dysfunction, Left; Zinc

SPECT Myocardial perfusion imaging (MPI) is associated with a relatively high radiation burden and decreasing image quality in heavy patients. Patient-specific low-activity protocols (PLAPs) are suggested but follow-up data is lacking. Our aim was to compare the use of a standard fixed-activity protocol (FAP) with a PLAP in cadmium zinc telluride (CZT)-SPECT MPI.. We retrospectively included 1255 consecutive patients who underwent CZT-SPECT stress-optional rest MPI. 668 Patients were scanned using FAP (370 MBq) and 587 patients using PLAP (2.25 MBq·kg. The percentage of scans interpreted as normal was 67% in FAP and 70% in PLAP groups (P = .29). The annualized hard event rates in these patients were 1.0% in the FAP and 0.9% in the PLAP group (P = .86). However, the mean radiation dose decreased by 23% for stress-only and by 15% to 2.6 mSv for stress-optional rest MPI after introduction of the PLAP (p<0.001).. Introduction of a patient-specific low-activity protocol does not affect the percentage of scans interpreted as normal or prognosis but significantly lowers the radiation dose for CZT-SPECT MPI.

Topics: Aged; Body Weight; Cadmium; Coronary Artery Disease; Electrocardiography; Female; Follow-Up Studies; Gamma Cameras; Humans; Male; Middle Aged; Myocardial Perfusion Imaging; Prognosis; Radiation Dosage; Radionuclide Imaging; Radiopharmaceuticals; Retrospective Studies; Tellurium; Tomography, Emission-Computed, Single-Photon; Zinc

Topics: Cadmium; Coronary Angiography; Coronary Artery Disease; Fractional Flow Reserve, Myocardial; Gamma Cameras; Humans; Middle Aged; Myocardial Perfusion Imaging; Reproducibility of Results; Tellurium; Zinc

The aim of this study was to assess the prognostic value of normal ultra-low-dose exercise MPI with a CZT camera.. 1901 consecutive patients without known CAD referred for exercise MPI with 1.8 MBq/kg (0.05 mCi) of Tc99m sestamibi or tetrofosmin and a CZT camera were included prospectively. Patients with an abnormal scan requiring an additional resting image (230) or a submaximal exercise test (271) were excluded. The 1400 remaining patients were followed for 39 months. The primary end-point was cardiac events (cardiac death, nonfatal myocardial infarction, and revascularization). The secondary end-point was noncardiac death.. The mean injected activity was 145 ± 37 MBq (3.9 ± 1 mCi), the mean acquisition duration was 10 ± 0.7 minutes, and the mean effective dose was 0.91 ± 0.13 mSv. 1288 patients (92%) achieved full follow-up. We observed 22 cardiac events and 16 noncardiac deaths. The annualized rates were equivalent to 0.55% for cardiac events and 0.37% for noncardiac mortality.. Normal ultra-low-dose exercise MPI with a CZT camera has a high negative predictive value. The effective dose was less than 1 mSv, and the study thus allays concerns about radiation burden.

Topics: Aged; Cadmium; Coronary Artery Disease; Exercise Test; Female; Follow-Up Studies; Humans; Kaplan-Meier Estimate; Male; Middle Aged; Myocardial Perfusion Imaging; Predictive Value of Tests; Prognosis; Prospective Studies; Technetium Tc 99m Sestamibi; Tellurium; Treatment Outcome; Zinc

We aimed to determine the optimal thallium 201 chloride (thallium-201) dose using a novel ultrafast cardiac gamma camera with cadmium-zinc-telluride (CZT) solid-state semiconductor detectors (D-SPECT).. The optimal thallium-201 dose for obtaining left ventricular (LV) myocardial counts was determined from a phantom study. Consecutive 292 patients underwent stress myocardial perfusion imaging with a thallium-201 injection. Stress test comprised exercise or pharmacological (adenosine) provocation. We calculated an optimal thallium-201 dose that resulted in better LV myocardial counts during 6 minutes of acquisition time. We corrected the respective values according to the patient's age, sex, body mass index (BMI), and type of stress test. The lowest thallium-201 dose for obtaining acceptable imaging was 1.2 million counts. Radiopharmaceutical doses showed a positive correlation with the patient's age (P < .001), sex (P = .012), BMI (P < .001), and type of stress test (P < .001). Multivariate analysis revealed that the patient's BMI and the type of stress test were statistically significant factors for determining the correct radiopharmaceutical dose (P < .001 for both).. For clinical use of the CZT SPECT system, the optimal individual thallium-201 doses can be determined based on the patient's BMI and type of stress test.

Topics: Aged; Aged, 80 and over; Cadmium; Coronary Artery Disease; Exercise Test; Female; Humans; Male; Middle Aged; Myocardial Perfusion Imaging; Phantoms, Imaging; Radiopharmaceuticals; Tellurium; Thallium Radioisotopes; Tomography, Emission-Computed, Single-Photon; Ventricular Function, Left; Zinc

Diagnostic performance of stress-only imaging using a Cadmium-Zinc-Telluride (CZT) camera has not been directly compared in the same patients to stress-only attenuation-corrected conventional Anger camera images.. 112 subjects with correlative coronary angiographic data and 40 subjects with <5% pre-test likelihood of coronary disease completed attenuation-corrected stress-only images on a conventional Anger camera and uncorrected upright and supine stress images on a CZT camera. Two readers provided independent, blinded interpretations of stress-only images.. Upright and supine stress-only CZT images and attenuation-corrected Anger camera images provided similar positive (reader 1/reader 2, 50.0%/44.1% vs 46.4%/51.9%) and negative (66.7%/64.0% vs 67.9%/67.7%) predictive values (all P = NS) for obstructive coronary artery disease; however, the sensitivity was higher (81.3% vs 58.3%, P = .05), specificity lower (29.7% vs 50.0%, P = .005), and normalcy rate lower (87.5% vs 100%, P = .025) with attenuation-corrected Anger camera images for the first reader with no significant differences between cameras for the second reader.. Stress-only upright and supine CZT imaging was non-inferior statistically to attenuation-corrected stress-only Anger camera imaging. Nevertheless, stress-only CZT imaging may be associated with reduced diagnostic sensitivity for some readers compared to attenuation-corrected Anger camera images, which may be less acceptable clinically compared to stress plus rest images.

Topics: Aged; Cadmium; Coronary Angiography; Coronary Artery Disease; Diagnosis, Computer-Assisted; Exercise Test; Female; Gamma Cameras; Humans; Image Processing, Computer-Assisted; Male; Middle Aged; Myocardial Perfusion Imaging; Observer Variation; Predictive Value of Tests; Reproducibility of Results; Sensitivity and Specificity; Tellurium; Tomography, Emission-Computed, Single-Photon; Zinc

The prognostic value of myocardial perfusion imaging (MPI) with the cadmium-zinc-telluride (CZT) SPECT camera is not well established. Therefore, the aim of the current study was to evaluate the prognostic value of MPI performed with a CZT SPECT camera in a large cohort of patients suspected of having coronary artery disease.

Topics: Cadmium; Coronary Artery Disease; Female; Follow-Up Studies; Gamma Cameras; Humans; Male; Middle Aged; Myocardial Perfusion Imaging; Prognosis; Tellurium; Tomography, Emission-Computed, Single-Photon; Zinc

To determine the prognostic value of a new, ultrafast, low dose myocardial perfusion SPECT (MPS) protocol in a cadmium-zinc telluride (CZT) camera. CZT cameras have introduced significant progress in MPS imaging, offering high-quality images despite lower doses and scan time. Yet, it is unknown if, with such protocol changes, the prognostic value of MPS is preserved. Patients had a 1-day 99 m-Tc-sestamibi protocol, starting with the rest (185-222 MBq) followed by stress (666-740 MBq). Acquisition times were 6 and 3 min, respectively. MPS were classified as normal or abnormal perfusion scans and summed scores of stress, rest, and difference (SSS, SRS and SDS), calculated. Patients were followed with 6-month phone calls. Hard events were defined as death or nonfatal myocardial infarction. Late revascularization was that occurring after 60 days of MPS. 2930 patients (age 64.0 ± 12.1 years, 53.3% male) were followed for 30.7 ± 7.5 months. Mean dosimetry was 6 mSv and mean total study time, 48 ± 13 min. The annual hard event and late revascularization rate were higher in patients with greater extension of defect and ischemia. SSS was higher in patients with hard events compared to those without events (2.6 ± 4.9 vs. 5.0 ± 6.3, p < 0.001), as well as the SDS (0.7 ± 1.9 vs. 1.7 ± 3.4, p < 0.00). The same was true for patients with or without late revascularization (SSS: 2.5 ± 4.7 vs. 6.6 ± 7.1; SDS: 0.6 ± 1.7 vs. 2.9 ± 3.8, p < 0.01). A new, faster, low-radiation, MPS protocol in a CZT camera maintain the ability to stratify patients with increased risk of events, showing that, in the presence of greater extension of defect or ischemia, patients presented higher rates of hard events and late revascularization.

Topics: Aged; Cadmium; Coronary Artery Disease; Coronary Circulation; Equipment Design; Female; Gamma Cameras; Humans; Male; Middle Aged; Myocardial Perfusion Imaging; Predictive Value of Tests; Prognosis; Prospective Studies; Radiation Dosage; Radiation Exposure; Radiopharmaceuticals; Technetium Tc 99m Sestamibi; Tellurium; Time Factors; Tomography, Emission-Computed, Single-Photon; Workflow; Zinc

Cadmium-zinc-telluride (CZT) cameras have improved the evaluation of patients with chest pain. However, inferior/inferolateral attenuation artifacts similar to those seen with conventional Anger cameras persist. We added prone acquisitions and CT attenuation correction (CTAC) to the standard supine image acquisition and analyzed the resulting examinations.. Seventy-two patients referred for invasive coronary angiography (CAG), and who also underwent rest/stress myocardial perfusion imaging (MPI) on a CZT camera in the supine and prone positions plus CTAC imaging, to examine known or suspected CAD between April 2013 and March 2014 were included. A sixteen-slice CT scan acquired on a SPECT/CT scanner between rest and stress imaging provided data for iterative reconstruction. Sensitivity, specificity, accuracy, and positive and negative likelihood ratios (LRs) were calculated to compare MPI with CAG on a per-patient basis. Per-patient sensitivity, specificity, and accuracy of supine images to predict coronary abnormalities on CAG were 35% [95% confidence interval (CI) 19-52], 86% (95% CI 80-92), and 74% (95% CI 66-82); those of prone imaging were 65% (95% CI 45-81), 82% (95% CI 76-87), and 78% (95% CI 68-85); and those of CTAC were 59% (95% CI 41-71), 93% (95% CI 87-97), and 85% (95% CI 76-91), respectively.. Prone acquisition and CTAC images improve the ability to assess the inferior/inferolateral area.

Topics: Aged; Cadmium; Coronary Artery Disease; Equipment Design; Equipment Failure Analysis; Female; Gamma Cameras; Humans; Image Enhancement; Male; Patient Positioning; Prone Position; Radionuclide Imaging; Reproducibility of Results; Sensitivity and Specificity; Tellurium; Tomography, Emission-Computed, Single-Photon; Zinc

Myocardial perfusion imaging (MPI) performed on traditional single-photon emission computed-tomography cameras has been shown to have a sub-optimal accuracy in detecting multivessel coronary artery disease (CAD).. Six-hundred and ninety-five patients were submitted to MPI on a novel cadmium-zinc-telluride (CZT) camera and coronary angiography. A coronary stenosis >70% was considered obstructive. In every patient, the summed stress score (SSS) was computed. Moreover, the regional stress scores were also calculated for every coronary territory.. Four-hundred and forty-one patients had obstructive CAD in one (28%), two (19%), or three (17%) vessels. At per-patient analysis, the SSS showed a significant accuracy in detecting obstructive CAD (AUC 0.87, P < .001). Specifically, its accuracy was maintained also in patients with double (AUC 0.83; P < .001) or triple-vessels disease (AUC 0.79, P < .001), where CZT was able to correctly identify CAD extent in 64% of patients. On a per-vessel basis, CZT confirmed its high accuracy in detecting obstructive CAD (AUC 0.88, P < .001), independently from the involved coronary vessel.. MPI performed on a CZT camera is highly accurate in detecting obstructive CAD, independently from the coronary artery involved and the overall disease burden.

Topics: Aged; Cadmium; Coronary Artery Disease; Female; Humans; Image Enhancement; Image Interpretation, Computer-Assisted; Male; Myocardial Perfusion Imaging; Radionuclide Imaging; Reproducibility of Results; Sensitivity and Specificity; Tellurium; Tomography, Emission-Computed, Single-Photon; Zinc

Topics: Coronary Angiography; Coronary Artery Disease; Myocardial Perfusion Imaging; Tellurium; Tomography, Emission-Computed, Single-Photon

Considering the distinctive characteristics of CZT detectors, automatic quantification of ischemia using normal limits included with software package may deliver suboptimal results for CAD detection. The present study aims to evaluate the benefits of creating normal limits specific to a local population and laboratory protocol.. Two groups were selected from patients who had undergone a CZT MPI. Normal limits were generated with the QPS application based on the population with low likelihood of CAD. Using the vendor-supplied and the population-specific normal limits i-TPD and vessel-specific SDS results obtained for patients who had subsequently undergone coronary angiography were compared with coronary angiography data. A weak correlation was observed for low i-TPD (stress TPD minus rest TPD) and SDS values. Both databases gave similar values for the area under the ROC curve concerning i-TPD (0.75 to 0.74) and SDS results (0.72 to 0.75 for the LAD, 0.62 to 0.64 for the LCx, and 0.63 to 0.67 for the RCA). Sensitivity (60%), specificity (78%), and predictive positive (84%) and negative (52%) values were also similar with a diagnostic and prognostic threshold value.. The use of a population-specific created database did not influence the diagnostic value of thallium-201 MPI QPS results using a CZT camera.

Topics: Cadmium; Coronary Artery Disease; Female; France; Humans; Male; Middle Aged; Myocardial Perfusion Imaging; Radionuclide Imaging; Radiopharmaceuticals; Reference Values; Reproducibility of Results; Sensitivity and Specificity; Tellurium; Thallium Radioisotopes; Tomography, Emission-Computed, Single-Photon; Zinc

To assess the impact of respiratory phase matching between single-photon-emission computed tomography myocardial perfusion imaging (SPECT-MPI) and low-dose computed tomography (CT) for attenuation correction (AC).. Compared with non-corrected breath-hold SPECT-MPI and with free-breathing AC SPECT-MPI, respiratory-phase-matched AC SPECT-MPI significantly affects segmental semi-quantitative uptake, increases the frequency of normal scans, yields the best inter-observer agreement, and significantly improves image quality. These findings suggest a potential role of respiratory triggered SPECT-MPI in clinical routine.

Topics: Aged; Cadmium; Cohort Studies; Computed Tomography Angiography; Coronary Artery Disease; Exercise Test; Female; Humans; Image Processing, Computer-Assisted; Male; Middle Aged; Myocardial Perfusion Imaging; Prospective Studies; Radionuclide Imaging; Respiration; Sensitivity and Specificity; Statistics, Nonparametric; Tellurium; Tomography, Emission-Computed, Single-Photon; Zinc

Transient ischemic dilation (TID) of the left ventricle (LV) has not been validated as a marker of extensive coronary artery disease (CAD) for studies using a cadmium-zinc-telluride (CZT) camera with upright imaging.. TID ratios were obtained from upright stress and rest images on a CZT camera. Separate cut-off values were determined for exercise and for regadenoson stress. The cutoffs were then applied to 28 patients with extensive CAD and 101 patients without extensive CAD.. With treadmill exercise, an upright TID ratio ≥1.16 provided a positive predictive value of 50% and a negative predictive value of 85.4% for the identification of extensive CAD. In the regadenoson group, an upright TID ratio of 1.29 provided a positive predictive value of 20% and a negative predictive value of 75.9%. Although not an independent predictor of extensive CAD in all subjects, in subjects with a normal upright LVEF, it provided a predictive value by receiver operating characteristics comparable to the SSS.. Increased upright TID measurements on a CZT camera are associated with extensive CAD. The upright TID measurements can serve in an adjunctive role to SSS, and may be most effective in patients with a normal upright exercise LVEF.

Topics: Aged; Cadmium; Cohort Studies; Coronary Angiography; Coronary Artery Disease; Diagnosis, Computer-Assisted; Dilatation; Exercise Test; Female; Heart Ventricles; Humans; Image Processing, Computer-Assisted; Ischemia; Male; Middle Aged; Myocardial Perfusion Imaging; Predictive Value of Tests; Purines; Pyrazoles; Retrospective Studies; ROC Curve; Sensitivity and Specificity; Tellurium; Tomography, Emission-Computed, Single-Photon; Zinc

Recent studies have shown that myocardial perfusion imaging (MPI) in cadmium-zinc-telluride (CZT) cameras allow faster exams with less radiation dose but there are little data comparing its prognosis information with that of dedicated cardiac Na-I SPECT cameras OBJECTIVE: The objective of this study is to compare the prognostic value of MPI using an ultrafast protocol with low radiation dose in a CZT-SPECT and a traditional one.. Group 1 was submitted to a two-day MIBI protocol in a conventional camera, and group 2 was submitted to a 1-day MIBI protocol in CZT camera. MPI were classified as normal or abnormal, and perfusion scores were calculated. Propensity score matching methods were performed RESULTS: 3554 patients were followed during 33±8 months. Groups 1 and 2 had similar distribution of age, gender, body mass index, risk factors, previous revascularization, and use of pharmacological stress. Group 1 had more abnormal scans, higher scores than group 2. Annualized hard events rate was higher in group 1 with normal scans but frequency of revascularization was similar to normal group 2. Patients with abnormal scans had similar event rates in both groups CONCLUSION: New protocol of MPI in CZT-SPECT showed similar prognostic results to those obtained in dedicated cardiac Na-I SPECT camera, with lower prevalence of hard events in patients with normal scan.

Topics: Brazil; Cadmium; Comorbidity; Coronary Artery Disease; Death, Sudden, Cardiac; Equipment Design; Equipment Failure Analysis; Female; Gamma Cameras; Humans; Incidence; Male; Middle Aged; Myocardial Perfusion Imaging; Reproducibility of Results; Risk Assessment; Sensitivity and Specificity; Survival Rate; Tellurium; Tomography, Emission-Computed, Single-Photon; Treatment Outcome; Zinc

An interaction between coronary anatomy, myocardial perfusion, and left ventricular (LV) functional parameters in the development of mechanical LV dyssynchrony (LVD) has been suggested. This study examined the correlates of LVD in a large sample size of patients with known or suspected coronary artery disease (CAD) using cadmium-zinc-telluride camera.. Six-hundred and fifty-seven consecutive patients who underwent myocardial perfusion imaging (MPI) and coronary angiography were included. Coronary stenosis >70% was considered significant. LV perfusion and functional parameters were computed from MPI images. The presence of significant LVD was evaluated by phase standard deviation and histogram bandwidth.. 415/657 (63%) patients had significant CAD. LVD was present in 247 (38%) patients and was associated with the presence of a higher CAD burden (P < .001), more impaired measures of LV perfusion (P < .001), contractile function (P < .001), and larger LV volumes (P < .001). By multivariate analysis, the LV end-systolic volume index (P < .001) and ischemic burden (P < .001) were the strongest predictors of LVD independent of CAD extent and LV systolic dysfunction.. LVD is frequent in patients undergoing MPI for suspected or known CAD. Its presence is independent of CAD burden and LV systolic dysfunction, but is dependent on the presence of myocardial perfusion abnormalities and LV end-systolic volume.

Topics: Aged; Cadmium; Causality; Comorbidity; Coronary Artery Disease; Exercise Test; Female; Humans; Italy; Male; Myocardial Perfusion Imaging; Radionuclide Imaging; Reproducibility of Results; Risk Factors; Sensitivity and Specificity; Stroke Volume; Tellurium; Ventricular Dysfunction, Left; Zinc

Single photon emission computed tomography (SPECT) myocardial perfusion imaging has proven to have prognostic importance in patients with suspected stable coronary artery disease (CAD). The recently introduced ultrafast cadmium zinc telluride (CZT)-based gamma cameras have been associated with less equivocal findings and more normal interpretations, allowing stress-only imaging to be performed more often. However, it is yet unclear whether normal stress-only CZT SPECT has comparable prognostic value as normally interpreted stress-only conventional SPECT.. The study population consisted of 1,650 consecutive patients without known CAD with normal stress-only myocardial perfusion results with either conventional (n = 362) or CZT SPECT (n = 1,288). The incidence of major adverse cardiac events (MACE, all-cause death, non-fatal myocardial infarction and/or coronary revascularization) was compared between the conventional SPECT and CZT SPECT groups. Multivariable analyses using the Cox model were used to adjust for differences in baseline variables.. Patients scanned with CZT were less often male (33 vs 39 %), had less often hypercholesterolaemia (41 vs 50 %) and had more often a family history of CAD (57 vs 49 %). At a median follow-up time of 37 months (interquartile range 28-45 months) MACE occurred in 68 patients. The incidence of MACE was 1.5 %/year in the CZT group, compared to 2.0 %/year in the conventional group (p = 0.08). After multivariate analyses, there was a trend to a lower incidence of MACE in the CZT SPECT group (hazard ratio 0.61, 95 % confidence interval 0.35-1.04, p = 0.07).. The prognostic value of normal stress-only CZT SPECT is at least comparable and may be even better than that of normal conventional stress SPECT.

Topics: Aged; Cadmium; Coronary Artery Disease; Exercise Test; Female; Humans; Male; Middle Aged; Myocardial Perfusion Imaging; Radiopharmaceuticals; Tellurium; Tomography, Emission-Computed, Single-Photon; Zinc

Computed tomography (CT)-based attenuation correction (AC) improves the accuracy of standard myocardial perfusion SPECT. Most dedicated cadmium-zinc-telluride (CZT) SPECT cameras are not equipped with an integrated CT component. We aimed to determine the impact of AC on diagnostic performance of CZT SPECT using co-registration with an external low-dose CT.. Sixty patients underwent CZT SPECT (GE Discovery 530c) with (99m)Tc-sestamibi at rest and following regadenoson stress. Using commercial software, SPECT images were co-registered with a low-dose CT acquired on a separate system (GE Discovery 670NMCT). Attenuation corrected and non-corrected (NC) images were reconstructed using an iterative algorithm. Accuracy was measured in 44 patients who had undergone invasive angiography within 6 months. Normalcy was compared in the remaining 16 patients who had a low pre-test likelihood (<5%) of coronary artery disease (CAD).. Summed stress and rest scores were significantly lower in AC images (9 ± 8 vs. 13 ± 9 and 6 ± 7 vs. 10 ± 9, P = 0.01), while summed difference score did not differ. According to angiography, 38 patients had significant CAD in 71 vascular territories. Attenuation correction improved accuracy globally (P = 0.03) and in RCA territory (P = 0.008). Specificity improved both globally (100 vs. 40%, P < 0.05) and in each individual territory (LAD: 63 vs. 36%, LCX: 70 vs. 33%, RCA: 81 vs. 19%, P < 0.01). Normalcy was 100% for AC and 62.5% for NC images (P < 0.05).. Attenuation correction with a co-registered external CT is feasible using CZT cameras and improves diagnostic accuracy mostly by improving specificity over uncorrected images.

Topics: Adult; Aged; Aged, 80 and over; Cadmium; Case-Control Studies; Coronary Angiography; Coronary Artery Disease; Female; Humans; Image Processing, Computer-Assisted; Male; Middle Aged; Myocardial Perfusion Imaging; Reference Values; ROC Curve; Sensitivity and Specificity; Severity of Illness Index; Tellurium; Tomography, Emission-Computed, Single-Photon; Tomography, X-Ray Computed; Zinc

Although stress single-photon emission computed tomography (SPECT) using a cadmium-zinc-telluride (CZT) camera facilitates radiation dose reduction, only a few studies have evaluated its diagnostic accuracy in Japanese patients by applying fractional flow reserve (FFR) measurements.. We prospectively evaluated 102 consecutive patients with suspected or known coronary artery disease with a low-dose stress/rest protocol ((99m)Tc radiotracer 185/370 MBq) using CZT SPECT. Within 3 months, coronary angiography was performed and a significant stenosis was defined as ≥90% diameter narrowing on visual estimation, or as a lesion of <90% and ≥ 50% stenosis with FFR ≤0.80. To detect individual coronary stenosis, the respective sensitivity, specificity, and accuracy were 86%, 75%, and 82% for left anterior descending artery stenosis, 76%, 81%, and 79% for left circumflex artery stenosis, and 87%, 92%, and 90% for right coronary artery stenosis. When limited to 92 intermediate stenotic lesions in which FFR was measured, stress SPECT showed 77% sensitivity, 91% specificity, and 84% accuracy, whereas the diagnostic value decreased to 52% sensitivity, 68% specificity, and 58% accuracy based only on visual estimation of ≥75% diameter narrowing.. CZT SPECT demonstrated a good diagnostic yield in detecting hemodynamically significant coronary stenoses as assessed by FFR, even when using a low-dose (99m)Tc protocol with an effective dose ≤5 mSv. (Circ J 2016; 80: 1217-1224).

Topics: Cadmium; Coronary Artery Disease; Coronary Stenosis; Fractional Flow Reserve, Myocardial; Humans; Prospective Studies; Radiopharmaceuticals; Sensitivity and Specificity; Technetium Tc 99m Sestamibi; Tellurium; Tomography, Emission-Computed, Single-Photon; Zinc

Identification of right ventricular (RV) abnormalities is important in patients with suspected coronary artery disease (CAD). RV activity can be better visualized on myocardial single-photon emission computerized tomography (SPECT) using a higher sensitivity cadmium-zinc-telluride (CZT) detector. The aim of this study was to investigate the clinical significance of RV/left ventricular (LV) uptake ratios during exercise thallium-201 SPECT using CZT detectors.. A total of 102 patients underwent treadmill ECG-gated SPECT, coronary angiography, and echocardiography. SPECT myocardial perfusion was interpreted using a 17-segment model and a 0-4-point scale. RV/LV uptake ratios were calculated on the basis of maximum counts per pixel within the entire RV and LV walls. The relationships between RV/LV uptake ratio and gated SPECT, presence of CAD (≥50% stenosis in the left main or ≥70% in the main branches), demographics, and echocardiographic parameters were analyzed.. Stress RV/LV ratios correlated positively with the presence of left main or multivessel disease, and tricuspid regurgitation maximum pressure gradient. After multivariate regression, stress/rest RV/LV ratios correlated positively with mitral flow deceleration time, age, female sex, and use of β-blockers.. RV/LV uptake ratios on the basis of exercise myocardial perfusion SPECT imaging using CZT cameras are useful for the detection of severe CAD and could serve as an indicator of pulmonary hypertension and LV diastolic dysfunction.

Topics: Adult; Aged; Aged, 80 and over; Cadmium Compounds; Cardiac-Gated Single-Photon Emission Computer-Assisted Tomography; Coronary Artery Disease; Equipment Design; Equipment Failure Analysis; Exercise Test; Female; Gamma Cameras; Humans; Male; Middle Aged; Radionuclide Ventriculography; Radiopharmaceuticals; Reproducibility of Results; Sensitivity and Specificity; Tellurium; Thallium Radioisotopes; Ventricular Dysfunction, Right; Zinc

The aim of this study was to evaluate the possible impact of stress-induced left ventricular (LV) diastolic dysfunction at cadmium-zinc-telluride (CZT) imaging, on the detection of significant coronary artery disease (CAD).. Four hundred and twenty-five consecutive patients underwent myocardial perfusion imaging at rest and after stress with a low-dose CZT protocol and the evaluation of coronary anatomy by invasive or computed coronary angiography. The summed difference score (SDS) was calculated in every patient. Left ventricular ejection fraction and peak filling rate (PFR) at baseline and after stress were derived from gated CZT images and the '% stress-to-rest' PFR difference, as an indicator of stress-induced diastolic dysfunction, determined. In the study population, the mean SDS was 5 ± 4, while mean stress PFR and rest PFR were 2.5 ± 0.8 end-diastolic volumes (EDV)/s and 2.5 ± 0.7 EDV/s, respectively. There was a strict correlation between the presence and extent of CAD and both myocardial SDS and '% stress-to-rest' PFR (P < 0.001 for both). Interestingly, while myocardial SDS and '% stress-to-rest' PFR were significantly correlated (P < 0.001), they resulted independent predictors of the presence of significant CAD (P < 0.001 and P < 0.032, respectively). Of note, at receiving operating characteristic analysis, a '% stress-to-rest' PFR ≤3 showed 71% sensitivity in unmasking the presence of significant coronary luminal narrowings.. The present study shows that the assessment of stress-induced diastolic dysfunction with an ultrafast scintigraphic protocol can improve the accuracy in detection of significant ischaemic heart disease.

Topics: Aged; Aged, 80 and over; Cadmium; Cohort Studies; Confidence Intervals; Coronary Angiography; Coronary Artery Disease; Disease Progression; Exercise Test; Female; Follow-Up Studies; Humans; Logistic Models; Male; Middle Aged; Myocardial Ischemia; Myocardial Perfusion Imaging; Odds Ratio; Retrospective Studies; ROC Curve; Sensitivity and Specificity; Severity of Illness Index; Stroke Volume; Tellurium; Tomography, X-Ray Computed; Ventricular Dysfunction, Left; Zinc

Recent advances in nuclear myocardial perfusion imaging (MPI) have made it possible to develop a dual-isotope protocol for high-speed acquisition with image quality and radiation delivery comparable to that obtained with conventional single isotope protocols. So far, no study has compared dual-isotope high-speed MPI to invasive coronary angiography (ICA) in a large cohort using a Cadmium-zinc-telluride SPECT system.. Over a 1-year period (May 2011 to April 2012), 1366 patients underwent dual-isotope high-speed MPI. Patients with ICA within 3 months after dual-isotope high-speed MPI were included together with patients with a low likelihood of coronary artery disease (CAD) in order to assess normalcy rate. Global summed stress score (SSS) and summed rest score (SRS) were calculated, and ICA results were analyzed independently. The main end point was a patient-based assessment of the diagnostic performance of dual-isotope high-speed MPI in detecting or ruling out significant CAD (>70% reduction in lumen diameter).. Inclusion criteria were fulfilled for 214 patients (143 men; age 60 ± 14 years; ICA, n = 104; low likelihood for CAD, n = 110). An exercise stress test was performed in 62% of patients and a pharmacological stress test was performed with either dipyridamole (32%) or dobutamine (6%). Average examination duration was 22.4 ± 4.5 minutes. Mean SSS, SRS, and SDS were 8.0 ± 4.9, 3.1 ± 4.3, and 5.0 ± 3.2, respectively. Prevalence of angiographic CAD was 75%. ICA detected stenosis in the left main trunk, left anterior descending artery, left circumflex artery, and right coronary artery in 4, 33, 31, and 42 patients, respectively. Sensitivity of dual-isotope high-speed MPI was 94%, normalcy rate was 92%, and accuracy was 83% for detecting CAD.. Dual-isotope high-speed MPI is reliable at detecting or ruling out CAD. NCT01785589.

Topics: Adult; Aged; Aged, 80 and over; Angina, Unstable; Cadmium; Cardiomyopathies; Cohort Studies; Coronary Angiography; Coronary Artery Bypass; Coronary Artery Disease; Exercise Test; Female; Humans; Male; Middle Aged; Myocardial Infarction; Myocardial Perfusion Imaging; Nuclear Medicine; Radiopharmaceuticals; Rest; Sensitivity and Specificity; Technetium Tc 99m Sestamibi; Tellurium; Thallium Radioisotopes; Tomography, Emission-Computed, Single-Photon; Ventricular Dysfunction, Left; Zinc

To evaluate the interplay between myocardial ischaemic burden and poststress left ventricular (LV) systolic and diastolic abnormalities in patients with suspected or known coronary artery disease (CAD).. A total of 471 patients underwent myocardial perfusion imaging by cadmium-zinc-telluride scintigraphy and coronary angiography. A fast imaging protocol was used with stress imaging performed 10 - 15 min after tracer injection. The summed difference score (SDS) and the percent stress-to-rest ratios for LV ejection fraction and peak filling rate (PFR), measures of stress-induced systolic and diastolic impairment, were computed from scintigraphic images. A SDS of >3 was considered abnormal and >7 a marker of moderate-to-severe ischaemia.. Of the 471 patients, 321 (68%) showed significant CAD in one (27%), two (23%) or three (18%) vessels. The extent of CAD associated with gradual alterations in SDS (P < 0.001). Interestingly, while impairment in the percent stress-to-rest PFR ratio paralleled the increase in the extent of CAD (P < 0.001 for trend), the occurrence of significant stress-induced systolic dysfunction was limited to patients with multivessel disease (P < 0.001 vs. patients without CAD, and P = 0.002 vs. patients with single-vessel disease). Similarly, while a strict correlation between percent stress-to-rest PFR ratio and myocardial ischaemic burden was evident (P < 0.001), significant stress-induced LV systolic impairment was limited to patients with moderate-to-severe ischaemia (P < 0.001 vs. patients with no or mild ischaemia).. Stress-induced LV diastolic impairment is associated with a less extensive ischaemic burden and CAD extent than poststress systolic dysfunction, which is limited to patients with multivessel CAD.

Topics: Aged; Cadmium; Coronary Artery Disease; Exercise Test; Female; Humans; Male; Middle Aged; Myocardial Perfusion Imaging; Tellurium; Ventricular Dysfunction, Left; Zinc

Myocardial perfusion imaging (MPI) may fail to detect balanced ischemia. We evaluated myocardial perfusion reserve (MPR) using Tl dynamic single-photon emission computed tomography (SPECT) and a novel cadmium zinc telluride (CZT) camera for predicting 3-vessel or left main coronary artery disease (CAD). METHODS AND RESULTS: A total of 55 consecutive patients with suspected CAD underwent SPECT-MPI and coronary angiography. The MPR index was calculated using the standard 2-compartment kinetic model. We analyzed the utility of MPR index, other SPECT findings, and various clinical variables. On multivariate analysis, MPR index and history of previous myocardial infarction (MI) predicted left main and 3-vessel disease. The area under the receiver operating characteristic curve was 0.81 for MPR index, 0.699 for history of previous MI, and 0.86 for MPR index plus history of previous MI. MPR index ≤1.5 yielded the highest diagnostic accuracy. Sensitivity, specificity, and accuracy were 86%, 78%, and 80%, respectively, for MPR index, 64%, 76%, 73% for previous MI, and 57%, 93%, and 84% for MPR index plus history of previous MI.. Quantification of MPR using dynamic SPECT and a novel CZT camera may identify balanced ischemia in patients with left main or 3-vessel disease.

Topics: Aged; Aged, 80 and over; Cadmium; Coronary Angiography; Coronary Artery Disease; Female; Humans; Male; Middle Aged; Models, Cardiovascular; Tellurium; Thallium; Tomography, Emission-Computed, Single-Photon; Zinc

Topics: Cadmium; Coronary Artery Disease; Female; Humans; Male; Myocardial Perfusion Imaging; Tellurium; Ventricular Dysfunction, Left; Zinc

To study the prognostic value of rapid-acquisition adenosine stress-rest myocardial perfusion scintigraphy (MPS) on a gamma camera using multipinhole collimation and cadmium-zinc-telluride (CZT) detectors. The secondary aim was to assess the diagnostic accuracy of the technique compared with invasive coronary angiography.. Retrospective analysis of 1109 consecutive patients undergoing MPS in a routine clinical setting on a high-efficiency multipinhole gamma camera. MPS acquisition, performed with a standard injection of 550 MBq of (99m)Tc-tetrofosmin, required a mean (±SD) scanning time of 322 ± 51 s. The hard cardiac event rate at a median (inter-quartile range) follow-up of 624 (552-699) days was 0.4% (95% CI 0.1-1.1) in patients with no significant perfusion abnormality versus 6.8% (95% CI 4.3-10.7%, P < 0.001) in those with an abnormal scan. In a sub-group of 165 patients, comparison with obstructive coronary artery disease on X-ray angiography gave a sensitivity, specificity, positive predictive value, negative predictive value, and accuracy for rapid-acquisition MPS of 84% (95% CI 74-91), 79% (95% CI 68-87), 82% (95% CI 72-89), 81% (95% CI 70-89), and 82% (95% CI 73-89), respectively.. MPS performed on a CZT solid-state detector camera with multipinhole collimation is an evolutionary development that provides reliable prognostic and diagnostic information, while significantly reducing image acquisition time.

Topics: Adult; Aged; Aged, 80 and over; Cadmium; Cardiac-Gated Single-Photon Emission Computer-Assisted Tomography; Cardiology; Cohort Studies; Coronary Angiography; Coronary Artery Disease; Female; Gamma Cameras; Humans; Kaplan-Meier Estimate; Male; Middle Aged; Myocardial Perfusion Imaging; Prognosis; Proportional Hazards Models; Retrospective Studies; Sensitivity and Specificity; Severity of Illness Index; Tellurium; Young Adult; Zinc

Recently introduced ultrafast cardiac SPECT cameras with cadmium zinc telluride-based (CZT) detectors may provide superior image quality allowing faster acquisition with reduced radiation doses. Although the level of concordance between conventional SPECT and invasive fractional flow reserve (FFR) measurement has been studied, that between FFR and CZT-based SPECT is not yet known. Therefore, we aimed to assess the level of concordance between CZT SPECT and FFR in a large patient group with stable coronary artery disease.. Both invasive FFR and myocardial perfusion imaging with a CZT-based SPECT camera, using Tc-tetrofosmin as tracer, were performed in 100 patients with stable angina and intermediate grade stenosis on invasive coronary angiography. A cut-off value of <0.75 was used to define abnormal FFR.. The mean age of the patients was 64 ± 11 years, and 64 % were men. SPECT demonstrated ischaemia in 31 % of the patients, and 20 % had FFR <0.75. The concordance between CZT SPECT and FFR was 73 % on a per-patient basis and 79 % on a per-vessel basis. Discordant findings were more often seen in older patients and were mainly (19 %) the result of ischaemic SPECT findings in patients with FFR ≥ 0.75, whereas only 8 % had an abnormal FFR without ischaemia as demonstrated by CZT SPECT.. Only 20 - 30 % of patients with intermediate coronary stenoses had significant ischaemia as assessed by CZT SPECT or invasive FFR. CZT SPECT showed a modest degree of concordance with FFR, which is comparable with previous results with conventional SPECT. Further investigations are particularly necessary in patients with normal SPECT and abnormal FFR, especially to determine whether these patients should undergo revascularization.

Topics: Aged; Cadmium; Cardiac-Gated Single-Photon Emission Computer-Assisted Tomography; Coronary Artery Disease; Female; Fractional Flow Reserve, Myocardial; Gamma Cameras; Humans; Male; Middle Aged; Myocardial Perfusion Imaging; Organophosphorus Compounds; Organotechnetium Compounds; Radiopharmaceuticals; Tellurium; Zinc

To evaluate the relationships between measures of left ventricular (LV) filling dynamics at cadmium-zinc-telluride (CZT) imaging and indexes of LV diastolic function at transthoracic echocardiography.. Two hundred and forty-seven patients underwent myocardial perfusion imaging at rest and after stress with a low-dose CZT protocol and a baseline transthoracic echocardiography study. All patients were submitted to invasive or computed coronary angiography. The peak filling rate (PFR) and the time to PFR (TPFR) were derived from gated CZT images as measures of LV filling dynamics. LV diastolic function was also evaluated at echocardiography and the presence of significantly increased LV filling pressures determined. Increased LV filling pressures at transthoracic echocardiography were evident in 103 (42%) patients. Interestingly, independently from the presence of coronary artery disease, there was a strict correlation between the presence and severity of LV diastolic dysfunction at echocardiography and CZT-derived measures of filling dynamics, i.e., PFR (P = 0.001) and TPFR (P = 0.001). At receiving operating characteristic analysis, a composite index of reduced PFR (≤2.11 end-diastolic volume s(-1)) and increased TPFR (>234 ms) showed a sensitivity of 84% and a specificity of 67% in unmasking the presence of elevated LV filling pressures at echocardiography.. CZT-derived measures of LV filling dynamics correlate with echocardiographic parameters of diastolic function and may identify the presence of increased LV filling pressures.

Topics: Aged; Cadmium; Coronary Angiography; Coronary Artery Disease; Echocardiography, Doppler; Exercise Test; Female; Humans; Image Interpretation, Computer-Assisted; Male; Myocardial Perfusion Imaging; Organophosphorus Compounds; Organotechnetium Compounds; Radiopharmaceuticals; Tellurium; Ventricular Dysfunction, Left; Zinc

Although combined supine and prone acquisitions improve the detection of inferolateral obstructive coronary artery disease (CAD), the predictors of inaccurate detection of inferolateral ischemia have not been reported by using cadmium zinc telluride (CZT) myocardial perfusion imaging (MPI).. Vasodilator stress (99m)Tc tetrofosmin MPI using CZT camera and coronary angiography was performed in 322 patients within an interval of 2 months. Prone MPI was performed immediately after supine MPI. Narrowing of the luminal diameter ≥ 75% was considered significant. The presence of an abnormality on both supine and prone images was considered significant. Combined supine and prone imaging, compared with supine-only quantification, was more specific (93% vs. 72%, respectively, p<0.0001) and accurate (88% vs. 74%, p<0.0001) without compromising sensitivity (82% vs. 68%, p=0.10). The area under the curve for detecting inferolateral ischemia was 0.769 (95% CI 0.705-0.833) for supine imaging and 0.802 (95% CI 0.730-0.875) for combined supine and prone imaging (p<0.05). Multivariable analysis revealed that previous inferolateral myocardial infarction was an independent predictor of a false diagnosis (odds ratio=3.45, 95% confidence interval [CI] 1.62-7.37, p<0.001).. Combined supine and prone quantitative CZT MPI enhances the detection of inferolateral CAD without adversely affecting its sensitivity. However, we recommend inferolateral ischemia be monitored in patients with a history of previous inferolateral MI because previous inferolateral MI is a predictor of inaccurate diagnosis.

Topics: Aged; Cadmium; Coronary Artery Disease; Female; Gamma Cameras; Humans; Male; Myocardial Perfusion Imaging; Patient Positioning; Prone Position; Reproducibility of Results; Retrospective Studies; Supine Position; Tellurium; Tomography, Emission-Computed, Single-Photon; Zinc

Coronary artery disease remains one of the most significant causes of morbidity and mortality among women. The published literature shows the importance of standard single photon emission computed tomography in the evaluation of women with known or suspected ischaemic heart disease, in terms of target intervention and clinical treatment. The purpose of the present study was to ascertain the diagnostic accuracy of cadmium-zinc-telluride (CZT) myocardial perfusion imaging according to gender, within a prospective database of patients with known or suspected coronary artery disease, using coronary angiography as the reference standard.. Included in the study were 309 consecutive patients, of whom 248 were men (80 %), with known or suspected coronary artery disease and who had been referred to our laboratory for stress-rest myocardial perfusion imaging. All patients underwent coronary angiography within 30 days. All patients underwent a single-day stress-rest low-dose ultrafast protocol. Fifteen minutes after the end of the stress (dose range 185 to 222 MBq of (99m)Tc-tetrofosmin), all patients underwent the first scan with an acquisition time of 7 min. The rest scan (dose range 370 to 444 MBq of (99m)Tc-tetrofosmin) was acquired from 30 min to 45 min after injection, with an acquisition time of 6 min. Images were visually inspected, and summed stress scores (SSS) and summed rest scores (SRS) were obtained.. Image quality was graded "good" or better in more than 90 % of patients. On coronary angiography, left main trunk stenosis, left anterior descending artery stenosis, left circumflex artery stenosis and right coronary artery stenosis were seen in 3, 155 , 142 and 131 patients, respectively. In women, the mean SSS and SRS were 8 ± 5 and 3 ± 1, respectively. Semiquantitative regional and global SSS were good discriminants of coronary artery disease, and the overall area under the receiver operator characteristic (ROC) curve was 0.822 (95 % CI 0.685 - 0.959). The value was comparable to that obtained in men (overall ROC area 0.884, 95 % CI 0.836 - 0.933).. A low-dose protocol with a CZT camera can be routinely used in women with known or suspected coronary artery disease without loss of accuracy and with lower radiation exposure of the patients.

Topics: Aged; Cadmium; Coronary Angiography; Coronary Artery Disease; Female; Gamma Cameras; Humans; Male; Middle Aged; Myocardial Perfusion Imaging; Positron-Emission Tomography; Reference Standards; Sex Factors; Tellurium; Tomography, Emission-Computed, Single-Photon; Zinc

The performance of a new single photon emission computed tomography (SPECT) scanner with a cadmium-zinc-telluride (CZT) solid-state semiconductor detector (Discovery NM 530c; D530c) was evaluated and compared to a conventional Anger-type SPECT with a dual-detector camera (Infinia).. Three different phantom studies were performed. Full width at half maximum (FWHM) was measured using line sources placed at different locations in a cylindrical phantom. Uniformity was measured using cylindrical phantoms with 3 different diameters (80, 120, and 160 mm). Spatial resolution was evaluated using hot-rod phantoms of various diameters (5, 9, 13, 16, and 20 mm). Three different myocardial phantom studies were also performed, acquiring projection data with and without defects, and evaluating the interference of liver and gallbladder radioactivity. In a clinical study, the D530c employed list-mode raw data acquisition with electrocardiogram (ECG)-gated acquisition over a 10-min period. From the 10-min projection data, 1-, 3-, 5-, 7- and 10-min SPECT images were reconstructed.. The FWHM of the D503c was 1.73-3.48 mm (without water) and 3.88-6.64 mm (with water), whereas the FWHM of the Infinia was 8.17-12.63 mm (without water) and 15.48-16.28 mm (with water). Non-uniformity was larger for the D530c than for the Infinia. Truncation artifacts were also observed with the D530c in a Φ160 mm phantom. The contrast ratio, as defined by myocardial defect/non-defect ratio, was better for the D530c than for the Infinia, and the influence from liver and gallbladder radioactivities was less. Quantitative gated SPECT (QGS) software demonstrated significant differences between data captured over a 10-min period, relative to those acquired over periods of <5 min; there was no difference between ejection fractions calculated using data capture for periods ≥5 min (p < 0.05).. The D530c is superior to the Infinia, with regard to both spatial resolution and sensitivity. In this study, these advantages were confirmed by the myocardial phantom and in a clinical setting, using the QGS software.

Topics: Adult; Aged; Cadmium; Coronary Artery Disease; Female; Heart; Humans; Male; Middle Aged; Phantoms, Imaging; Semiconductors; Tellurium; Tomography, Emission-Computed, Single-Photon; Zinc

For a 1-day myocardial perfusion SPECT (MPS) the recommendations for administered activity stated in the EANM guidelines results in an effective dose of up to 16 mSv per patient. Recently, a gamma camera system, based on cadmium zinc telluride (CZT) technology, was introduced. This technique has the potential to reduce the effective dose and scan time compared to the conventional NaI gamma camera. The aim of this study was to investigate if the effective dose can be reduced with a preserved image quality using CZT technology in MPS.. In total, 150 patients were included in the study. All underwent a 1-day (99m)Tc-tetrofosmin stress-rest protocol and were divided into three subgroups (n = 50 in each group) with 4, 3, and 2.5 MBq/kg body weight of administered activity in the stress examination, respectively. The acquisition time was increased in proportion to the decrease in administered activity. All examinations were analyzed for image quality by visual grading on a 4-point scale (1 = poor, 2 = adequate, 3 = good, 4 = excellent), by two expert readers.. The total effective dose (stress + rest) decreased from 9.3 to 5.8 mSv comparing 4 to 2.5 MBq/kg body weight. For the patients undergoing stress examination only (35%) the effective dose, administrating 2.5 MBq/kg, was 1.4 mSv. The image acquisition times for 2.5 MBq/kg body weight were 475 and 300 seconds (stress and rest) compared to 900 seconds for each when using conventional MPS. The average image quality was 3.7 ± 0.5, 3.8 ± 0.5, and 3.8 ± 0.4 for the stress images and 3.5 ± 0.6, 3.6 ± 0.6, and 3.5 ± 0.6 for the rest images and showed no statistically significant difference (P = .62) among the 4, 3, and 2.5 MBq/kg groups.. The new CZT technology can be used to considerably decrease the effective dose and acquisition time for MPS with preserved high image quality.

Topics: Aged; Body Weight; Cadmium; Coronary Artery Disease; Female; Gamma Cameras; Humans; Image Processing, Computer-Assisted; Likelihood Functions; Male; Middle Aged; Myocardial Perfusion Imaging; Organophosphorus Compounds; Organotechnetium Compounds; Perfusion; Radiation Dosage; Radiometry; Radiopharmaceuticals; Tellurium; Time Factors; Tomography, Emission-Computed, Single-Photon; Treatment Outcome; Zinc

Low yield of invasive coronary angiography and unnecessary coronary interventions have been identified as key cost drivers in cardiology for evaluation of coronary artery disease (CAD). This has fuelled the search for noninvasive techniques providing comprehensive functional and anatomical information on coronary lesions. We have evaluated the impact of implementation of a novel hybrid cadmium-zinc-telluride (CZT)/64-slice CT camera into the daily clinical routine on downstream resource utilization.. Sixty-two patients with known or suspected CAD were referred for same-day single-session hybrid evaluation with CZT myocardial perfusion imaging (MPI) and coronary CT angiography (CCTA). Hybrid MPI/CCTA images from the integrated CZT/CT camera served for decision-making towards conservative versus invasive management. Based on the hybrid images patients were classified into those with and those without matched findings. Matched findings were defined as the combination of MPI defect with a stenosis by CCTA in the coronary artery subtending the respective territory. All patients with normal MPI and CCTA as well as those with isolated MPI or CCTA finding or combined but unmatched findings were categorized as "no match".. All 23 patients with a matched finding underwent invasive coronary angiography and 21 (91%) were revascularized. Of the 39 patients with no match, 5 (13%, p < 0.001 vs matched) underwent catheterization and 3 (8%, p < 0.001 vs matched) were revascularized.. Cardiac hybrid imaging in CAD evaluation has a profound impact on patient management and may contribute to optimal downstream resource utilization.

Topics: Cadmium; Coronary Artery Disease; Female; Heart; Humans; Male; Middle Aged; Myocardial Perfusion Imaging; Retrospective Studies; Systems Integration; Tellurium; Time Factors; Tomography, X-Ray Computed; Zinc

The new ultrafast cardiac single photon emission computed tomography (SPECT) cameras with cadmium-zinc-telluride (CZT)-based detectors are faster and produce higher quality images as compared to conventional SPECT cameras. We assessed the need for additional imaging, total imaging time, tracer dose and 1-year outcome between patients scanned with the CZT camera and a conventional SPECT camera.. A total of 456 consecutive stable patients without known coronary artery disease underwent myocardial perfusion imaging on a hybrid SPECT/CT (64-slice) scanner using either conventional (n = 225) or CZT SPECT (n = 231). All patients started with low-dose stress imaging, combined with coronary calcium scoring. Rest imaging was only done when initial stress SPECT testing was equivocal or abnormal. Coronary CT angiography was subsequently performed in cases of ischaemic or equivocal SPECT findings. Furthermore, 1-year clinical follow-up was obtained with regard to coronary revascularization, nonfatal myocardial infarction or death.. Baseline characteristics were comparable between the two groups. With the CZT camera, the need for rest imaging (35 vs 56%, p < 0.001) and additional coronary CT angiography (20 vs 28%, p = 0.025) was significantly lower as compared with the conventional camera. This resulted in a lower mean total administered isotope dose per patient (658 ± 390 vs 840 ± 421 MBq, p < 0.001) and shorter imaging time (6.39 ± 1.91 vs 20.40 ± 7.46 min, p < 0.001) with the CZT camera. After 1 year, clinical outcome was comparable between the two groups.. As compared to images on a conventional SPECT camera, stress myocardial perfusion images acquired on a CZT camera are more frequently interpreted as normal with identical clinical outcome after 1-year follow-up. This lowers the need for additional testing, results in lower mean radiation dose and shortens imaging time.

Topics: Cadmium; Coronary Artery Disease; Female; Follow-Up Studies; Humans; Male; Middle Aged; Myocardial Perfusion Imaging; Prognosis; Radiation Dosage; Retrospective Studies; Stress, Physiological; Tellurium; Time Factors; Tomography, Emission-Computed, Single-Photon; Zinc

We evaluated the diagnostic accuracy of attenuation corrected nuclear myocardial perfusion imaging (MPI) with a novel hybrid single photon emission computed tomography (SPECT)/CT device consisting of an ultrafast dedicated cardiac gamma camera with cadmium-zinc-telluride (CZT) solid-state semiconductor detectors integrated onto a multislice CT scanner to detect coronary artery disease (CAD). Invasive coronary angiography served as the standard of reference.. The study population included 66 patients (79% men; mean age 63 ± 11 years) who underwent 1-day (99m)Tc-tetrofosmin pharmacological stress/rest examination and angiography within 3 months. Sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) as well as accuracy of the CT X-ray based attenuation corrected CZT MPI for detection of CAD (≥ 50% luminal narrowing) was calculated on a per-patient basis.. The prevalence of angiographic CAD in the study population was 82%. Sensitivity, specificity, PPV, NPV and accuracy were 87, 67, 92, 53 and 83%, respectively.. In this first report on CZT SPECT/CT MPI comparison versus angiography we confirm a high accuracy for detection of angiographically documented CAD.

Topics: Adult; Aged; Aged, 80 and over; Cadmium; Coronary Angiography; Coronary Artery Disease; Female; Humans; Image Processing, Computer-Assisted; Male; Middle Aged; Multimodal Imaging; Myocardial Perfusion Imaging; Positron-Emission Tomography; Reference Standards; Sensitivity and Specificity; Tellurium; Tomography, X-Ray Computed; Zinc

We aimed at establishing the optimal scan time for nuclear myocardial perfusion imaging (MPI) on an ultrafast cardiac gamma-camera using a novel cadmium-zinc-telluride (CZT) solid-state detector technology.. Twenty patients (17 male; BMI range, 21.7-35.5 kg/m(2)) underwent 1-d (99m)Tc-tetrofosmin adenosine stress and rest MPI protocols, each with a 15-min acquisition on a standard dual-detector SPECT camera. All scans were immediately repeated on an ultrafast CZT camera over a 6-min acquisition time and reconstructed from list-mode raw data to obtain scan durations of 1 min, 2 min, etc., up to a maximum of 6 min. For each of the scan durations, the segmental tracer uptake value (percentage of maximum myocardial uptake) from the CZT camera was compared by intraclass correlation with standard SPECT camera data using a 20-segment model, and clinical agreement was assessed per coronary territory. Scan durations above which no further relevant improvement in uptake correlation was found were defined as minimal required scan times, for which Bland-Altman limits of agreement were calculated.. Minimal required scan times were 3 min for low dose (r = 0.81; P < 0.001; Bland-Altman, -11.4% to 12.2%) and 2 min for high dose (r = 0.80; P < 0.001; Bland-Altman, -7.6% to 12.9%), yielding a clinical agreement of 95% and 97%, respectively.. We have established the minimal scan time for a CZT solid-state detector system, which allows 1-d stress/rest MPI with a substantially reduced acquisition time resulting in excellent agreement with regard to uptake and clinical findings, compared with MPI from a standard dual-head SPECT gamma-camera.

Topics: Adult; Aged; Aged, 80 and over; Cadmium; Coronary Artery Disease; Coronary Circulation; Dose-Response Relationship, Drug; Female; Gamma Cameras; Heart; Humans; Image Processing, Computer-Assisted; Linear Models; Male; Microcomputers; Middle Aged; Organophosphorus Compounds; Organotechnetium Compounds; Perfusion; Phantoms, Imaging; Radiopharmaceuticals; Tellurium; Tomography, Emission-Computed, Single-Photon; Zinc