technetium-tc-99m-tetrofosmin and Coronary-Stenosis

In myocardial SPECT imaging with the popularly used 99mTc-sestamibi and 99mTc-tetrofosmin, intense liver uptake leads to a paradoxical decrease of counts in the absence of perfusion abnormalities, making it difficult to assess myocardial perfusion, particularly in the inferior or inferoapical left ventricular wall. 99mTc-N-DBODC5, which is a new lipophilic, mono-cationic nitride myocardial perfusion imaging agent, exhibits high myocardial uptake and excellent bio-distribution kinetics with rapid liver clearance in rats and dogs. 99mTc-N-DBODC5 myocardial imaging during vasodilator stress can determine the severity of stenosis, though underestimates occur with mild coronary stenosis compared to 201Tl, in a similar way to what occurs with 99mTc-sestamibi and 99mTc-tetrofosmin. In particular, 99mTc-N-DBODC5's rapid liver clearance, which may significantly reduce the photon scatter from the liver, allows for the reduction of artifactual decreased myocardial perfusion and the improvement of the diagnostic accuracy of coronary artery disease.

Topics: Animals; Coronary Artery Disease; Coronary Circulation; Coronary Stenosis; Dogs; Heart; Humans; Liver; Organophosphorus Compounds; Organotechnetium Compounds; Technetium Tc 99m Sestamibi; Tissue Distribution; Tomography, Emission-Computed, Single-Photon

Little is known about the effect of chronic beta-blockade on adenosine actions. We sought to investigate the effect of oral beta-blockers on the presence, extent, and severity of myocardial perfusion abnormality induced by adenosine in patients with coronary artery disease.. In this crossover study, 45 male patients with coronary artery disease on beta-blocker therapy with atenolol, bisoprolol, or metoprolol underwent adenosine myocardial perfusion imaging both on and off beta-blockade in a random order on separate days. Myocardial perfusion was assessed both qualitatively and quantitatively. Hemodynamic response, image analysis, and sensitivity for the detection of coronary stenosis (>or=50% luminal diameter reduction on x-ray coronary angiography) were compared between the on and off beta-blocker studies.. Rate pressure product both at baseline and at peak adenosine infusion decreased by 23% +/- 15% and 21% +/- 18%, respectively, after beta-blockade (P < 0.001 for all). The median (interquartile range) summed difference score, a measure of defect reversibility, and quantitative defect size were both significantly lower after beta-blockade (median, 7.0 [interquartile range, 2.0-9.5] vs. median, 5.0 [interquartile range, 0-8.0], P = 0.002; and quantitative defect size, 18% [interquartile range, 9%-34%] vs. quantitative defect size, 6% [interquartile range, 0%-19%], P < 0.001, respectively). The overall sensitivity for the detection of coronary stenosis decreased from 0.76 (95% confidence interval, 0.65-0.88) to 0.58 (95% confidence interval, 0.45-0.71) after beta-blockade (P = 0.03).. beta-blockade causes a small but significant reduction in the extent and severity of perfusion abnormality by adenosine. This may reduce the diagnostic sensitivity of adenosine myocardial perfusion imaging for the detection of flow-limiting coronary stenosis.

Topics: Adenosine; Adrenergic beta-Antagonists; Aged; Atenolol; Blood Pressure; Coronary Angiography; Coronary Circulation; Coronary Disease; Coronary Stenosis; Cross-Over Studies; Electrocardiography; Female; Heart; Heart Rate; Humans; Male; Middle Aged; Myocardial Ischemia; Organophosphorus Compounds; Organotechnetium Compounds; Tomography, Emission-Computed, Single-Photon; Vasodilator Agents

We used myocardial fractional flow reserve (FFR(myo)) and coronary flow reserve (CFR) to estimate cut-off values for assessment of the functional severity of coronary stenosis and myocardial ischemia, and we tested the usefulness of coronary blood hemodynamic measurements before and after plain old balloon angioplasty (POBA) and coronary artery bypass graft surgery (CABG).. Fractional flow reserve and CFR are useful for assessing the functional severity of coronary artery stenosis, coronary microvascular dysfunction, and myocardial ischemia during cardiac catheterization in adults. However, there have been no reports on the use of these measurements in children with Kawasaki disease (KD).. The study group included 128 patients with 314 coronary branches. The subjects were classified into three groups: normal coronary group, with 206 branches; abnormal coronary artery without ischemia group, with 58 branches; and ischemia group, with 50 branches.. In each branch, CFR and FFR(myo) were significantly lower in the ischemia group than in the other groups. Cut-off values for assessing the functional severity of coronary stenosis and CFR were approximately equal to those obtained for adults (CFR: <2.0; FFR(myo): <0.75). We obtained very high sensitivity and specificity for estimating myocardial ischemia using CFR and FFR(myo) (CFR: 94.0% and 98.5%, respectively; FFR(myo): 95.7% and 99.1%, respectively). Both CFR and FFR(myo) were reliable indicators of coronary hemodynamics before and after POBA and CABG.. Together, CFR and FFR(myo) provide a useful index for assessing the functional severity of coronary artery stenosis and myocardial ischemia and estimating the effectiveness of POBA and CABG in children with KD, the same as they do for adults.

Topics: Angioplasty, Balloon; Blood Flow Velocity; Case-Control Studies; Child; Coronary Artery Bypass; Coronary Circulation; Coronary Stenosis; Female; Humans; Male; Mucocutaneous Lymph Node Syndrome; Myocardial Ischemia; Organophosphorus Compounds; Organotechnetium Compounds; Radiopharmaceuticals; Sensitivity and Specificity; Tomography, Emission-Computed, Single-Photon; Ultrasonography, Interventional

It is not known whether pretreatment with nicorandil, an ATP-sensitive K+ channel (K(ATP)channel) opener, induces a preconditioning effect independent of increased collateral recruitment.. Forty-four patients with angina who underwent percutaneous transluminal coronary angioplasty (PTCA) to proximal left anterior descending artery (LAD) stenosis were randomly allocated for pretreatment with an intravenous injection of 80 g/kg nicorandil 5 min before initial ballooning (n=22) or saline (n=22). 99mTc tetrofosmin was injected during balloon inflation, quantitative analysis of occlusion images by SPECT was conducted, and the defect severity score (SS) was calculated. An ECG was recorded during the 2-min inflation to calculate the sum of ST elevation (sigmaST).. SigmaST levels were significantly reduced in patients with nicorandil pretreatment compared with control patients (control:1.89+/-0.85 mV nicorandil:1.24+/-0.57 mV, p=0.0052). However, no difference was observed in defect severity (control: 79.0+/-32.5, nicorandil: 98.7+/-48.9 ns). A close correlation was observed between SS and sigmaST in both groups (nicorandil group R(2)=0.505, control group R(2)=0.599). A multivariate regression model demonstrated that both defect severity (p<0.0001) and pretreatment with nicorandil (p<0.001) were significantly related to the level of sigmaST, suggesting a cellular protective effect against ischaemia by nicorandil, independent of myocardial blood flow.. Nicorandil pretreatment resulted in the induction of myocardial preconditioning independent of the severity of ischaemia.

Topics: Aged; Angioplasty, Balloon, Coronary; Calcium Channel Agonists; Collateral Circulation; Coronary Stenosis; Female; Humans; Ischemic Preconditioning, Myocardial; Male; Middle Aged; Myocardial Ischemia; Myocardial Revascularization; Nicorandil; Organophosphorus Compounds; Organotechnetium Compounds; Radionuclide Imaging; Radiopharmaceuticals; Vasodilator Agents

Topics: Coronary Angiography; Coronary Stenosis; Dipyridamole; Echocardiography; Electrocardiography; Exercise Test; Humans; Male; Middle Aged; Myocardial Perfusion Imaging; Organophosphorus Compounds; Organotechnetium Compounds; Tomography, Emission-Computed, Single-Photon; Vasodilator Agents

Transposition of the great arteries is a congenital heart defect defined by an abnormal connection between the aorta, pulmonary artery, and the ventricles, resulting in parallel systemic and pulmonary circulations. Long-term follow-up data of patients who underwent correction via an arterial switch operation have recently shown that as a result of re-implantation of the coronary arteries in the neo-aorta, coronary stenosis and occlusion are relatively common complications. In this report, we discuss two cases illustrating the added value of myocardial perfusion imaging (MPI) and cardiac CT for the assessment of these patients. Based on the available literature we conclude that MPI and cardiac CT are excellent non-invasive methods to evaluate coronary anatomy and myocardial function also in this specific group of patients.

Topics: Adolescent; Coronary Angiography; Coronary Stenosis; Coronary Vessels; Exercise; Heart; Heart Ventricles; Humans; Male; Myocardial Ischemia; Myocardial Perfusion Imaging; Organophosphorus Compounds; Organotechnetium Compounds; Radionuclide Imaging; Risk; Tomography, Emission-Computed, Single-Photon; Tomography, X-Ray Computed; Transposition of Great Vessels

The study evaluated the automatic prediction of obstructive disease from myocardial perfusion imaging (MPI) by deep learning as compared with total perfusion deficit (TPD).. Deep convolutional neural networks trained with a large multicenter population may provide improved prediction of per-patient and per-vessel coronary artery disease from single-photon emission computed tomography MPI.. A total of 1,638 patients (67% men) without known coronary artery disease, undergoing stress. A total of 1,018 (62%) patients and 1,797 of 4,914 (37%) arteries had obstructive disease. Area under the receiver-operating characteristic curve for disease prediction by deep learning was higher than for TPD (per patient: 0.80 vs. 0.78; per vessel: 0.76 vs. 0.73: p < 0.01). With deep learning threshold set to the same specificity as TPD, per-patient sensitivity improved from 79.8% (TPD) to 82.3% (deep learning) (p < 0.05), and per-vessel sensitivity improved from 64.4% (TPD) to 69.8% (deep learning) (p < 0.01).. Deep learning has the potential to improve automatic interpretation of MPI as compared with current clinical methods.

Topics: Aged; Aged, 80 and over; Coronary Circulation; Coronary Stenosis; Deep Learning; Female; Humans; Image Interpretation, Computer-Assisted; Male; Middle Aged; Myocardial Perfusion Imaging; Organophosphorus Compounds; Organotechnetium Compounds; Predictive Value of Tests; Radiopharmaceuticals; Registries; Technetium Tc 99m Sestamibi; Tomography, Emission-Computed, Single-Photon

The aim of this study was to evaluate the clinical feasibility of simultaneous acquisition of rest (99m)Tc-tetrofosmin/stress (201)Tl dual-isotope single-photon emission computed tomography with a semiconductor gamma camera.. Ninety-four patients with known or suspected coronary artery disease (CAD) were enrolled in the study. First, patients were injected with (99m)Tc-tetrofosmin (296 MBq) for rest imaging, followed by (201)Tl (74 MBq) injection during 6 min of vasodilator stress test. Immediately after the stress test, the patients underwent the first electrocardiogram (ECG)-gated simultaneous acquisition including rest and stress perfusion scans. Patients were brought back for the second simultaneous acquisition for the comparison of ECG-gated wall motion between stress and rest scan 30 min later. Coronary angiography was performed in all the patients within 3 months of this protocol. Sensitivity, specificity and accuracy on a per patient basis to detect significant coronary artery stenosis (≥75%) were 88.6%, 79.2% and 86.2%, respectively. Per coronary vessel, sensitivity, specificity and accuracy were as follows: 84.9%, 80.5% and 83% in the left anterior descending coronary artery; 75%, 93.1% and 86.2% in the left circumflex coronary artery; and 74.2%, 85.7% and 81.9% in the right coronary artery.. Simultaneous acquisition of rest (99m)Tc-tetrofosmin/stress (201)Tl dual-isotope protocol had high diagnostic accuracy for significant CAD. (Circ J 2016; 80: 689-695).

Topics: Aged; Coronary Artery Disease; Coronary Stenosis; Female; Humans; Male; Middle Aged; Myocardial Perfusion Imaging; Organophosphorus Compounds; Organotechnetium Compounds; Tomography, Emission-Computed, Single-Photon

Quantification of myocardial perfusion reserve (MPR) is an emerging topic in nuclear cardiology with an expected diagnostic and prognostic incremental value, especially for patients with severe coronary artery disease. The advent of new dedicated solid-state cameras has opened new perspectives for perfusion quantitation in SPECT. We appraised the feasibility of perfusion reserve estimation using a cadmium zinc telluride camera in a cohort of multivessel patients and its pertinence with respect to angiographic data.. Twenty-three patients with known multivessel coronary artery disease were prospectively enrolled. Dynamic SPECT acquisitions using (99m)Tc-tetrofosmin at rest and after vasodilator stress were performed using a dedicated cadmium zinc telluride camera. Reconstructed frames were automatically segmented to extract the vascular input function and the myocardial uptake curve. One-compartment kinetic modeling was used to estimate global and regional uptake values, and then myocardial blood flow was derived using the Renkin-Crone equation. Global and regional MPR was assessed using flow difference (stress - rest) and flow ratio (stress/rest). All patients underwent control coronary angiography within 4 wk, which served as the reference for MPR index assessment. Relevant angiographic findings included maximal stenosis and (for a subgroup of 26 vessels) invasive measurement of fractional flow reserve (FFR). A stenosis was considered obstructive if greater than 50% and an FFR abnormal if lower than 0.8.. Global MPR correlated well with number of obstructed vessels (P < 0.001). After multivariate analysis, both regional flow ratio and flow difference were significantly associated with maximal stenosis (P < 0.001) and FFR (P < 0.001). Regional MPR indices were significantly different in obstructed and nonobstructed vessels (P < 0.001) and in vessels with normal and abnormal FFR (P < 0.001). With a cutoff of 2, the sensitivity, specificity, and accuracy of regional flow ratio were, respectively, 80%, 85%, and 81% for the detection of obstructed vessels and 89%, 82%, and 85% for the detection of abnormal FFR.. Scintigraphic estimations of global and regional MPR in multivessel patients using a cadmium zinc telluride camera appear to correlate well with invasive angiographic findings, including maximal stenosis and FFR measurements.

Topics: Aged; Cohort Studies; Coronary Angiography; Coronary Artery Disease; Coronary Stenosis; Exercise Test; Feasibility Studies; Female; Fractional Flow Reserve, Myocardial; Heart; Humans; Male; Middle Aged; Myocardial Perfusion Imaging; Organophosphorus Compounds; Organotechnetium Compounds; Perfusion; Prospective Studies; Radiopharmaceuticals; Tomography, Emission-Computed, Single-Photon

SPECT myocardial perfusion imaging (MPI) is commonly used for comprehensive interpretation of metabolic PET FDG imaging in ischemic dysfunctional myocardium. We evaluated the difference in scan interpretation introduced by CT attenuation correction (CTAC) of SPECT MPI in patients undergoing viability characterization by (99m)Tc SPECT MPI/PET FDG. In 46 consecutive patients (mean age 64, range 36-83 years) with dysfunctional myocardium, we analyzed viability from combined SPECT MPI and PET FDG scanning without attenuation correction (NC) and with CTAC for SPECT MPI. FDG uptake was classified in groups of percent uptake using the segment with maximum tracer in SPECT perfusion uptake as reference. Viability patterns were categorized as normal, mismatch, mild match and scar by relative comparison of SPECT and PET. Applying CTAC introduced a different reference segment for the normalization of PET FDG study in 57% of cases. As a result, the flow-metabolism pattern changed in 28% of segments, yielding a normal, mismatch, mild match and scar pattern in 462, 150, 123, and 47 segments with NC and 553, 86, 108, and 35 with CTAC, respectively (P = 0.001). Thus, by introducing CTAC for SPECT MPI 25% of segments originally classified as scar were reclassified and the number of normal segments increased by 20%. Introducing CTAC decreased by 54% the number of patients with possible indication for revascularization, from 26/46 to 12/46 (P < 0.001). Different interpretation of myocardial viability can be observed when using CTAC instead of NC SPECT MPI as reference for PET FDG scans.

Topics: Adult; Aged; Aged, 80 and over; Coronary Circulation; Coronary Stenosis; Female; Fluorodeoxyglucose F18; Humans; Image Interpretation, Computer-Assisted; Male; Middle Aged; Myocardial Ischemia; Myocardial Perfusion Imaging; Myocardium; Organophosphorus Compounds; Organotechnetium Compounds; Positron-Emission Tomography; Predictive Value of Tests; Radiopharmaceuticals; Severity of Illness Index; Switzerland; Tissue Survival; Tomography, Emission-Computed, Single-Photon; Tomography, X-Ray Computed

Cardiac hybrid imaging by fusing single-photon emission computed tomography (SPECT) myocardial perfusion imaging with coronary computed tomography angiography (CCTA) provides important complementary diagnostic information for coronary artery disease (CAD) assessment. We aimed at assessing the impact of cardiac hybrid imaging on the choice of treatment strategy selection for CAD.. Three hundred and eighteen consecutive patients underwent a 1 day stress/rest (99m)Tc-tetrofosmin SPECT and a CCTA on a separate scanner for evaluation of CAD. Patients were divided into one of the following three groups according to findings in the hybrid images obtained by fusing SPECT and CCTA: (i) matched finding of stenosis by CCTA and corresponding reversible SPECT defect; (ii) unmatched CCTA and SPECT finding; (iii) normal finding by both CCTA and SPECT. Follow-up was confined to the first 60 days after hybrid imaging as this allows best to assess treatment strategy decisions including the revascularization procedure triggered by its findings. Hybrid images revealed matched, unmatched, and normal findings in 51, 74, and 193 patients. The revascularization rate within 60 days was 41, 11, and 0% for matched, unmatched, and normal findings, respectively (P< 0.001 for all inter-group comparisons).. Cardiac hybrid imaging with SPECT and CCTA provides an added clinical value for decision making with regard to treatment strategy for CAD.

Topics: Aged; Coronary Artery Disease; Coronary Stenosis; Feasibility Studies; Female; Humans; Male; Middle Aged; Myocardial Perfusion Imaging; Myocardial Revascularization; Organophosphorus Compounds; Organotechnetium Compounds; Radiopharmaceuticals; Tomography, Emission-Computed, Single-Photon; Tomography, X-Ray Computed

Numerous non-invasive techniques are developed to assess the severity of coronary artery disease (CAD). Coronary angiography (CAG) is an established method for the diagnosis and to quantify the severity of coronary artery stenosis. Single photon emission computed tomography-myocardial perfusion imaging (SPECT-MPI) using Technetium-99m (Tc-99m) tetrofosmin is also a useful established technique for the assessment of severity of CAD. This prospective observational study was carried out in Bangabandhu Sheikh Mujib Medical University (BSMMU) to assess the severity of coronary artery stenosis using Tc-99m Single Photon Emission Computed Tomography myocardial perfusion imaging (SPECT-MPI) in comparison with CAG. Eighty two (82) consecutive patients with mean age 53.51(SD+/-7.08) years and Candian Cardiovascular Society (CCS) class I and II severity of chest pain, male: female ratio (4.8:1) was studied. Tc-99m SPECT-MPI was performed by one-day exercise stress and rest protocol. A total of two hundred and forty six coronary artery territories examined in this study. By CAG normal coronary arteries were found in seventy six, moderate stenosis in twenty four and severe stenosis in one hundred and forty-six coronary artery territories whereas SPECT-MPI found normal perfusion in twenty seven, mild perfusion abnormality in seventeen, moderate perfusion abnormality in thirty two and severe perfusion abnormality in one hundred and sixty five coronary artery territories. Sensitivity and specificity of SPECT-MPI using Tc-99m tetrofosmin in detecting coronary artery stenosis were 87.09% and 80.95% respectively. The positive predictive value, negative predictive value and accuracy of the test were 91.01%, 73.91% and 85.18% respectively. From this study it can be concluded that Tc-99m SPECT-MPI was a safe, effective and excellent non-invasive tool for the detection of severity of coronary artery lesion and can be used to predict severity of CAD.

Topics: Adult; Aged; Coronary Circulation; Coronary Stenosis; Female; Humans; Male; Middle Aged; Myocardial Perfusion Imaging; Organophosphorus Compounds; Organotechnetium Compounds; Prospective Studies; Tomography, Emission-Computed, Single-Photon

To define the impact of attenuation correction (AC) on interpretation of perfusion abnormalities induced by left bundle branch block (LBBB) in myocardial perfusion imaging (MPI) and single photon emission computed tomography (SPECT).. Thirty-six patients with spontaneous and 12 with pacemaker (PM)-induced LBBB (mean age 68.6 +/- 9.7) underwent gated 1-day adenosine stress/rest Tc-99m tetrofosmin SPECT on a hybrid SPECT-CT dual-head detector camera with Hawkeye facility (Infinia, GE Healthcare, Milwaukee, WI). Images were analyzed using iterative reconstruction (IR) and AC by computerized tomography (IR-AC) and compared with filtered back protection (FBP) as a standard of reference. Defect extent and severity for the anterior, septal, apical, inferior, and lateral regions were assessed by computerized analysis. The combination of septal with anterior and/or apical perfusion defects was attributed to the typical LBBB-induced pattern.. LBBB caused a typical perfusion pattern in 24 patients with spontaneous and in 10 with PM-induced LBBB, whereas MPI was normal in 14 patients. FBP revealed a partial reversibility of anterior (spontaneous LBBB) and apical-septal (spontaneous and PM-induced LBBB) defect severity. By IR-AC, LBBB caused comparable anteroseptal reversible perfusion defects (P < 0.05) but fixed apical defects. Apical-septal defect severity was higher and defect extent was larger in IR-AC compared with FBP (both P < 0.05). Defect extent was unchanged between rest and stress for both reconstructions.. Spontaneous and PM-induced LBBB often induces typical perfusion defects in MPI at stress, partly reversible at rest. With IR-AC this typical pattern is more pronounced and less reversible, strengthening the confidence to discriminate such findings from ischemia.

Topics: Aged; Bundle-Branch Block; Coronary Angiography; Coronary Stenosis; Diagnosis, Differential; Electrocardiography; Exercise Test; Female; Gated Blood-Pool Imaging; Heart; Humans; Image Processing, Computer-Assisted; Male; Middle Aged; Organophosphorus Compounds; Organotechnetium Compounds; Radiopharmaceuticals; Tomography, Emission-Computed, Single-Photon

If coronary artery was treated with optimal stent implantation, myocardial perfusion in the territory supplied by a dilated coronary artery should be not reversible. However, several studies have demonstrated reversible perfusion in the territory supplied by a coronary artery with an optimally implanted stent. The main objective of this study was to evaluate the incidence of reversible defects detected by M-SPECT early after optimal PTCA with stent implantation. Its second objective was to determine the predictive value of detecting reversible defects after stent implantation for late restenosis.. About 66 patients that underwent M-SPECT within 24 h of successful PTCA with stent implantation were included. All patients were followed up clinically and angiographically. The incidence of reversible perfusion defects on M-SPECT and the rate of late restenosis in target coronary arteries were evaluated retrospectively.. Reversible perfusion defects on M-SPECT were observed in 26% of the patients and in 36% of lesions following successful PTCA with stent implantation. The incidence of late restenosis was significantly higher in patients and lesions with reversible perfusion defects (47% vs. 18%). According to binary logistic regression analysis, the presence of a reversible perfusion defects was the only independent predictor of late restenosis.

Topics: Adult; Aged; Aged, 80 and over; Angioplasty, Balloon, Coronary; Coronary Angiography; Coronary Circulation; Coronary Restenosis; Coronary Stenosis; Female; Humans; Logistic Models; Male; Middle Aged; Organophosphorus Compounds; Organotechnetium Compounds; Predictive Value of Tests; Radiopharmaceuticals; Retrospective Studies; Risk Assessment; Stents; Tomography, Emission-Computed, Single-Photon; Treatment Outcome

The coronary angiography provides information on the anatomical state of the coronary tree, while myocardial perfusion scintigraphy (MPI) facilitates the evaluation of the grade of ischaemia that a particular stenosis produces. The purpose of MPI is to detect the coronary stenosis that provokes the ischaemia and is termed the "culprit lesion". The aim of this study was to evaluate the accuracy of 1-day DypEX 99mTc-tetrofosmin tomography in the identification and localization of culprit lesion in the patients with known coronary artery disease (CAD).. Ninety-one (91) patients with known CAD were studied. In all of them significant coronary narowing (> 75% luminal stenosis) was angiographically detected. All the patients were submitted to 2 i.v. injections of 99mTc-tetrofosmin, one in a peak of pharmacologic dipyridamole stress protocol with concomitant low level bicycle exercise 50W (DypEX) and the other 3 h after exercise. Quantification of regional tetrofosmin uptake was performed using short-axis myocardial tomogram that was divided on 17 segments for each study. Reversibility score (RS) > or =3 determinated culprit lesion. Two of segments with scor 5 (index of reversibility scor--IRS) in the territory of coronary artery stenoses determinated culprit lesion.. A total of 273 vascular territories (4641 segments) were analyzed before percutaneous coronary intervention (PCI). Overall sensivity, specificit, and accuracy using RS > or =3 and IRS were 90.1%, 87.1%, 89.4%, with positive predictive value 95.8%, and 94.1%, 93.3%, 94%, with positive predictive value 98%, respectively.. RS and IRS significantly improve sensitivity, specificity, and accuracy for determination of culprit lesion in patients undergoing PCI.

Topics: Angioplasty, Balloon, Coronary; Coronary Circulation; Coronary Disease; Coronary Stenosis; Dipyridamole; Elective Surgical Procedures; Exercise Test; Female; Humans; Male; Organophosphorus Compounds; Organotechnetium Compounds; Radiopharmaceuticals; Sensitivity and Specificity; Tomography, Emission-Computed, Single-Photon

CT angiography (CTA) offers a valuable alternative for the diagnosis of CAD but its value in the detection of functionally relevant coronary stenoses remains uncertain. We prospectively compared the accuracy of 64-slice CTA with that of myocardial perfusion imaging (MPI) using (99m)Tc-tetrofosmin-SPECT as the gold standard for the detection of functionally relevant coronary artery disease (CAD).. MPI and 64-slice CT were performed in 100 consecutive patients. CTA lesions were analysed quantitatively and area stenoses > or =50% and > or =75% were compared with the MPI findings.. In 23 patients, MPI perfusion defects were found (12 reversible, 13 fixed). A total of 399 coronary arteries and 1,386 segments was analysed. Eighty-four segments (6.1%) in 23 coronary arteries (5.8%) of nine patients (9.0%) were excluded owing to insufficient image quality. In the remaining 1,302 segments, quantitative CTA revealed stenoses > or =50% in 57 of 376 coronary arteries (15.2%) and stenoses > or =75% in 32 (8.5%) coronary arteries. Using a cut-off at > or =75% area stenosis, CTA yielded the following sensitivity, specificity, negative (NPV) and positive predictive value (PPV), and accuracy for the detection of any (fixed and reversible) MPI defect: by patient, 75%, 90%, 93%, 68% and 87%, respectively; by artery, 76%, 95%, 99%, 50% and 94%, respectively.. Sixty-four-slice CTA is a reliable tool to rule out functionally relevant CAD in a non-selected population with an intermediate pretest likelihood of disease. However, an abnormal CTA is a poor predictor of ischaemia.

Topics: Adult; Aged; Aged, 80 and over; Coronary Angiography; Coronary Artery Disease; Coronary Stenosis; Coronary Vessels; Female; Humans; Male; Middle Aged; Myocardium; Organophosphorus Compounds; Organotechnetium Compounds; Perfusion; Prospective Studies; Tomography, Emission-Computed, Single-Photon; Tomography, X-Ray Computed

Myocardial perfusion imaging plays an important role in clinical management of coronary artery disease, but the most commonly used radionuclides significantly underestimate the severity of coronary artery stenosis. The objective of this study was to evaluate the potential clinical utility of the PET compound (18)F-fluorobenzyl triphenyl phosphonium ((18)F-FBnTP) and characterize its capacity to assess the severity of coronary artery stenosis in a canine model in vivo and ex vivo.. (18)F-FBnTP myocardial uptake was measured in 17 dogs with various degrees of stenosis of the left anterior descending (LAD) or circumflex (LCx) coronary arteries during adenosine vasodilation, using dynamic PET and gamma-well counting. True myocardial blood flow in ischemic (IS) and nonischemic (NIS) beds of the left ventricle was determined with radioactive microspheres. (18)F-FBnTP and (99m)Tc-tetrofosmin activities were compared in 8 dogs ex vivo.. The quantitative assessment of the perfusion defect was significantly (P < 0.03) more accurate with (18)F-FBnTP than with (99m)Tc-tetrofosmin, in mild (IS/NIS; 0.72 +/- 0.08, 0.93 +/- 0.07, respectively, mean +/- SE) and severe stenosis (0.42 +/- 0.05, 0.64 +/- 0.08, respectively), compared with microsphere flow (mild, 0.43 +/- 0.06; severe, 0.22 +/- 0.04). The IS/NIS ratio of both radionuclides correlated linearly with microsphere flow disparity with a similar slope. Flow defect contrast was 2.7 times greater for (18)F-FBnTP than for (99m)Tc-tetrofosmin, as inferred from the regression line intercept (0.14 vs. 0.38, respectively). The (18)F-FBnTP PET IS/NIS ratio (mild, 0.70 +/- 0.04; severe, 0.46 +/- 0.02), did not differ statistically (P >or= 0.330) from that measured ex vivo. A nearly identical qualitative and quantitative estimate of stenosis severity was obtained by early, short (5-15-min) and delayed, prolonged (30-60-min) (18)F-FBnTP PET scans. The stenotic area measured by PET was 16% smaller than that defined by tissue staining.. (18)F-FBnTP PET is a promising new technology for rapid noninvasive detection and assessment of perfusion defect severity in the myocardium.

Topics: Animals; Coronary Stenosis; Dogs; Female; Fluorine Radioisotopes; Heart Ventricles; Male; Myocardium; Organophosphorus Compounds; Organotechnetium Compounds; Perfusion; Positron-Emission Tomography; Radiopharmaceuticals; Regional Blood Flow

Thallium 201, technetium 99m sestamibi (MIBI), and Tc-99m tetrofosmin differ in their myocardial uptake characteristics. This may make the technetium tracers less sensitive for detecting mild to moderate coronary stenosis.. We identified 163 patients with angiographic mild to moderate stenosis (50%-89%) and coexistent severe disease (88/163 patients) from a previous study of patients who received either thallium, MIBI, or tetrofosmin for myocardial perfusion scintigraphy. Summed segmental uptake scores were used to assess myocardial perfusion of territories supplied by the mildly to moderately stenotic vessels. Mean (+/- SD) summed stress uptake scores in the left anterior descending artery territory were 21.4 +/- 3.8, 21.6 +/- 4.2, and 22.1 +/- 2.3 for thallium, MIBI, and tetrofosmin, respectively (P = .7); mean summed difference uptake scores were 1.2 +/- 1.8, 1.1 +/- 1.9, and 1.0 +/- 1.1, respectively (P = .8). In the non-left anterior descending artery territory, mean summed stress uptake scores were 32.5 +/- 6.3, 34.0 +/- 6.3, and 34.5 +/- 4.7 for thallium, MIBI, and tetrofosmin, respectively (P = .4), whereas mean summed difference scores were 1.9 +/- 2.6, 1.7 +/- 2.2, and 1.7 +/- 2.3, respectively (P = .9).. There were no significant differences between the tracers for the summed uptake scores. This suggests that the 3 tracers are comparable in clinical practice for assessing the extent and severity of perfusion abnormalities arising from mild to moderate coronary artery stenosis, especially in the presence of coexistent severe disease.

Topics: Coronary Stenosis; Female; Humans; Male; Middle Aged; Organophosphorus Compounds; Organotechnetium Compounds; Radionuclide Imaging; Radiopharmaceuticals; Reproducibility of Results; Retrospective Studies; Sensitivity and Specificity; Severity of Illness Index; Technetium Tc 99m Sestamibi; Thallium

Earlier studies have suggested a modest accuracy of stress thallium 201 myocardial perfusion imaging (MPI) for the diagnosis of coronary artery disease (CAD) in women. The accuracy of stress MPI with technetium 99m tetrofosmin has not been studied in women. The aim of this study was to assess the accuracy of stress Tc-99m tetrofosmin MPI for the diagnosis and localization of CAD in women.. We studied 88 women who underwent exercise or dobutamine stress Tc-99m tetrofosmin tomography and coronary angiography within 3 months. Significant CAD was defined as a stenosis 50% or greater in diameter in at least 1 major epicardial coronary artery. Myocardial perfusion abnormalities were detected in 44 of 53 patients with significant CAD and in 7 of 35 patients without significant CAD (overall sensitivity, 83% [95% confidence interval (CI), 73%-93%]; specificity, 80% [95% CI, 67%-93%]; and accuracy, 82% [95% CI, 74%-90%]). The sensitivity was 72% (18/25) in patients with single-vessel CAD and 93% (26/28) in patients with multivessel CAD. Perfusion abnormalities were detected in 2 or more vascular distributions in 20 of 28 patients with multivessel CAD and in 4 of 60 patients without multivessel CAD (sensitivity for the identification of multivessel CAD, 71% [95% CI, 55%-88%]; specificity, 93% [95% CI, 86%-98%]; and accuracy, 86% [95% CI, 79%-93%]). The sensitivity, specificity, and accuracy were 82%, 84%, and 83%, respectively, for the diagnosis of CAD in the left anterior descending artery; 77%, 84%, and 81%, respectively, for CAD in the right coronary artery; and 74%, 80%, and 78%, respectively, for CAD in the left circumflex artery.. Stress Tc-99m tetrofosmin MPI is an accurate noninvasive technique for the diagnosis and localization of CAD in women.

Topics: Aged; Coronary Angiography; Coronary Artery Disease; Coronary Stenosis; Female; Humans; Middle Aged; Myocardial Ischemia; Organophosphorus Compounds; Organotechnetium Compounds; Radionuclide Imaging; Radiopharmaceuticals; Reproducibility of Results; Tomography, X-Ray Computed

To evaluate the reproducibility and operator dependence for the quantitative regional left ventricular functional parameters (LVFP) assessed by Cedars-Sinai's Quantitative automated gated SPECT (QGS) software.. The QGS algorithm was reviewed in detail and potential operator dependencies were defined. Series of prototypes were selected, consisting of (a) normal perfusion, (b) perfusion defects in all perfusion regions, (c) perfusion studies of patients with angiographic confirmed normal coronary arteries, proximal (>or=70% stenoses) single and multiple vessel disease, and (d) spurious activity in close proximity. While defining and re-orienting the volume containing the left ventricle, the operator adjusted 8 variables/degrees of freedom (DF). The software was used without further operator interventions. Results were expressed as a coefficient of variation (COV). Separate COV were calculated per distinct DF. A segment was considered not robust when the COV did exceed 20% in a single DF, 15% in at least 2 DF, or 10% in at least 3 DF.. Regional left ventricular EF and volumes showed excellent reproducibility. Normal perfusion and the vessel disease prototypes showed an excellent COV (for all re-orientation steps [33/prototype]) mostly below 5% for LVFP. However, regional wall motion and thickening became less reliable in the presence of large perfusion defects or artifacts.. Quantitative estimates for regional left ventricular functional data show excellent reproducibility using automated gated SPECT. However, there may be substantial operator dependency in the presence of large defects or spurious activity in close proximity.

Topics: Algorithms; Coronary Artery Disease; Coronary Stenosis; Echocardiography, Stress; Exercise Test; Gated Blood-Pool Imaging; Humans; Image Processing, Computer-Assisted; Organophosphorus Compounds; Organotechnetium Compounds; Radiopharmaceuticals; Reproducibility of Results; Software; Stroke Volume; Tomography, Emission-Computed, Single-Photon; Ventricular Dysfunction, Left

Evaluation of myocardial ischemia and viability is very important for the management of patients with a history of Kawasaki disease (KD). (99m)Tc-tetrofosmin myocardial perfusion scintigraphy combined with quantitative gated single photon computed emission tomography (QGS) gives us information, not only about perfusion, but also the percentage change in left ventricular wall thickness (%WT) and relative changes in left ventricular wall motion (LVM).. The subjects were 27 patients with a history of KD followed as outpatients at the National Cardiovascular Center, Osaka, Japan. Exercise-loaded QGS was performed on 21 patients, and dipyridamole- loaded QGS was performed in six patients younger than 7 years old.. Perfusion defects (PD) were observed in 12 patients. Of the 12 patients, four with old myocardial infarction (OMI) had decreased %WT. All patients with OMI showed a decrease in %WT in the areas where PD was seen on the image. The other eight patients without OMI showed no decrease in %WT. In non-infarcted cases, the %WT was normal in the PD-positive area.. It is possible to evaluate myocardial ischemia and viability in KD patients by comparing PD on the image with %WT determined by QGS using exercise or drug-loaded myocardial scintigraphy alone.

Topics: Adolescent; Adult; Child; Child, Preschool; Coronary Stenosis; Dipyridamole; Exercise Test; Female; Humans; Male; Mucocutaneous Lymph Node Syndrome; Myocardial Infarction; Myocardial Ischemia; Organophosphorus Compounds; Organotechnetium Compounds; Radiopharmaceuticals; Tissue Survival; Tomography, Emission-Computed, Single-Photon; Vasodilator Agents

Several studies have demonstrated a correlation between myocardial ischemia and severity of coronary lesions as determined by intravascular ultrasound (IVUS) and fractional flow reserve (FFR) measurements. However, their value for the assessment of mild coronary stenoses that are associated with myocardial perfusion abnormalities has not been well studied. The objective of this study was to prospectively compare the results of myocardial perfusion as determined by exercise/dipyridamole myocardial single-photon emission computed tomography with IVUS and FFR measurements in patients who had angiographically mild coronary stenosis (< 50% diameter stenosis by quantitative coronary angiography). Forty-eight patients who had stable coronary disease (61 +/- 11 years of age; 6 women) were included. All had mild coronary stenosis in the proximal/middle segment of > or = 1 coronary artery and had undergone maximal exercise myocardial technetium-99m tetrofosmin single-photon emission computed tomography within 48 hours before coronary angiography. IVUS measurements included lesion lumen area, external elastic membrane area, lesion plaque burden (calculated as external elastic membrane minus lumen area, divided by external elastic membrane, and multiplied by 100), and lumen area stenosis (calculated as reference lumen area minus lesion lumen area, divided by reference lumen area, multiplied by 100). Fifty-three coronary lesions were studied, with a mean percent diameter stenosis of 34.9 +/- 7.9% on angiography. Myocardial perfusion defects were demonstrated by single-photon emission computed tomography in 11 patients (12 myocardial regions) with no differences in lesion percent diameter stenosis compared with those without perfusion defects. The presence of reversible perfusion defects was associated with a higher lesion plaque burden as evaluated by IVUS (67.4 +/- 8.1% vs 60.2 +/- 9.3%, p = 0.01). FFR values did not differ in the presence or absence of perfusion defects (0.90 +/- 0.06 vs 0.92 +/- 0.07, respectively; p = NS). In conclusion, plaque burden as determined by IVUS may partly explain the presence of myocardial perfusion defects in cases of angiographically nonsignificant coronary lesions. However, the high FFR values associated with these lesions suggest that other mechanisms, such as endothelial/microvascular dysfunction, might also account for perfusion abnormalities in these patients.

Topics: Blood Pressure; Coronary Angiography; Coronary Stenosis; Coronary Vessels; Exercise Test; Female; Follow-Up Studies; Humans; Male; Middle Aged; Organophosphorus Compounds; Organotechnetium Compounds; Prognosis; Prospective Studies; Radiopharmaceuticals; Severity of Illness Index; Tomography, Emission-Computed, Single-Photon; Ultrasonography, Interventional

The aim of this study was to evaluate the significance of extension of exercise-induced ischemia toward apex of left ventricle.. After injections of technetium-99m tetrofosmin at peak ergometer exercise and thallium-201 at 3 min post-exercise, dual-isotope single photon emission computed tomography (SPECT) images were obtained simultaneously with cross-talk compensation using triple-energy window in 70 patients (65.8+/-9.5 years) with angiographically proven ischemic heart disease. The left ventricle was divided into a total of 18 areas in 3 levels of apical, middle, basal, and the extent and localization of ischemia to long axis of left ventricle were measured at peak exercise and 3 min into the recovery.. Of 57 patients with exercise-induced reversible ischemia, in 25 patients with the ischemia in 2 levels to long axis of left ventricle, the ischemia extended mainly to the middle and basal levels (p<0.0001) and was localized during recovery mainly in the basal level (p<0.0005). In 21 patients with the ischemia in all 3 levels, the ischemia was localized during recovery mainly to the middle and basal levels (p<0.05). The persistence of ischemia in apex at post-exercise reflected the delay of recovery from ischemia on the whole of left ventricle and was related to the enlargement of resting end-diastolic volume of left ventricle as compared to the quick recovery of ischemia in apex (p<0.0005 and p<0.05, respectively).. Although the ischemia recovers earliest in the peripheral apical level within exercise-induced ischemic territory, the delay of recovery from the ischemia in the apical level may be related to the development of heart failure, independent of intensity of occurred ischemia during exercise.

Topics: Aged; Cardiac Catheterization; Case-Control Studies; Coronary Stenosis; Exercise Test; Female; Heart; Heart Ventricles; Humans; Male; Myocardial Ischemia; Organophosphorus Compounds; Organotechnetium Compounds; Radiopharmaceuticals; Thallium Radioisotopes; Tomography, Emission-Computed, Single-Photon

Topics: Aorta; Blood Pressure; Cardiac Catheterization; Coronary Circulation; Coronary Stenosis; Coronary Vessels; Dipyridamole; Echocardiography, Stress; Exercise Test; Humans; Organophosphorus Compounds; Organotechnetium Compounds; Radiopharmaceuticals; Sensitivity and Specificity; Severity of Illness Index; Single-Blind Method; Tomography, Emission-Computed, Single-Photon; Vasodilator Agents

The diagnostic value of myocardial perfusion scintigraphy in patients with left bundle branch block (LBBB) and previous acute myocardial infarction has not been evaluated.. To determine the utility of single photon emission computed tomography (SPECT) in patients with LBBB and previous acute myocardial infarction.. Seventy two consecutive patients with permanent LBBB and previous acute myocardial infarction were studied with stress-rest SPECT using 99mTc compounds. The same stress procedures were followed in all patients: (1) exercise alone when it was sufficient; (2) exercise plus simultaneous administration of dipyridamole if exercise was insufficient.. In 26 of 28 patients (93%) who had a Q wave acute myocardial infarct before the development of LBBB, there was concordance between abnormal Q waves and rest SPECT in the localisation of myocardial necrosis (kappa = 0.836; p = 0.0001). In 48 patients who had coronary angiography, the positive predictive value of exercise (+dipyridamole) myocardial SPECT for the diagnosis of left anterior descending coronary artery stenosis was 93%, for left circumflex coronary artery stenosis, 96%, and for right coronary artery stenosis, 89%. Specificity values were 83%, 91%, and 69%, respectively. However, sensitivity (69%, 64%, and 89%) and negative predictive values (48%, 46%, and 82%) were suboptimal.. Rest myocardial perfusion SPECT with technetium compounds is useful for localising healed myocardial infarction in patients with LBBB, and exercise (+dipyridamole) SPECT has a high positive predictive value and specificity for the diagnosis of coronary stenosis in these patients.

Topics: Aged; Analysis of Variance; Bundle-Branch Block; Coronary Stenosis; Dipyridamole; Exercise Test; Female; Humans; Male; Myocardial Infarction; Organophosphorus Compounds; Organotechnetium Compounds; Radiopharmaceuticals; Sensitivity and Specificity; Tomography, Emission-Computed, Single-Photon; Vasodilator Agents

To assess whether 15-(p-[iodine-123] iodophenyl)-3-(R,S) methylpentadecanoic acid (BMIPP) imaging can identify previous ischemic areas, BMIPP SPECT was performed in patients with acute chest pain to compare its findings with those of technetium-99m-tetrofosmin (tetrofosmin) SPECT and coronary angiography.. Basic studies indicate that BMIPP can identify previous ischemia as reduced tracer uptake.. This study prospectively enrolled 111 consecutive patients with acute chest pain without myocardial infarction. Tetrofosmin SPECT was performed at rest within 24 h after the last episode of chest pain. Coronary angiography and BMIPP SPECT were also performed on the following day.. Sixty-four of the 87 patients with coronary stenosis or spasm showed BMIPP abnormalities corresponding to the areas of coronary abnormalities (sensitivity 74%), whereas only 33 of them showed perfusion abnormalities (sensitivity 38%) (p < 0.001). Of 24 patients [corrected] without coronary stenosis or spasm, 22 showed normal BMIPP SPECT (specificity = 92%) [corrected] and 23 showed normal tetrofosmin SPECT (sensitivity = 96%) [corrected]. Coronary stenosis was more often seen in the group with abnormal tetrofosmin/abnormal BMIPP (82%) and with normal tetrofosmin/abnormal BMIPP (69%) than in the group with normal tetrofosmin/normal BMIPP (36%) (p < 0.05). Coronary spasm was observed more often in the group with abnormal tetrofosmin/abnormal BMIPP (83%) and with normal tetrofosmin/abnormal BMIPP (90%) than in the group with normal tetrofosmin/normal BMIPP (27%) (p < 0.05). The extent and severity scores of tetrofosmin and BMIPP in the patients with organic stenosis were significantly higher than those of patients with no organic stenosis or spasm (p < 0.0001).. These data indicate that BMIPP SPECT may specifically identify previous ischemic lesions due to coronary stenosis or spasm in patients with acute chest pain.

Topics: Aged; Angina Pectoris; Chest Pain; Coronary Angiography; Coronary Stenosis; Coronary Vasospasm; Diagnosis, Differential; Fatty Acids; Female; Humans; Iodobenzenes; Male; Middle Aged; Myocardial Infarction; Organophosphorus Compounds; Organotechnetium Compounds; Predictive Value of Tests; Tomography, Emission-Computed, Single-Photon