technetium-tc-99m-tetrofosmin and Death--Sudden--Cardiac

Myocardial perfusion abnormality in the left ventricle is known to be prognostic in patients with hypertrophic cardiomyopathy (HCM). Magnetic resonance imaging and necropsy studies on HCM hearts revealed myocardial lesions predominating in the area of ventricular septum-free wall junction. We assessed perfusion abnormality in this area and correlated it with the prognosis of HCM patients. We performed exercise Tc-99m tetrofosmin myocardial scintigraphy in 55 patients with nonobstructive HCM. Perfusion abnormalities were semiquantified using a 5-point scoring system in small areas of anterior junctions of basal, mid, and apical short axis views in addition to a conventional 17-segment model. All patients were prospectively followed for sudden death, cardiovascular death and hospitalization for heart failure or stroke associated with atrial fibrillation. Cardiovascular events occurred in 10 patients during an average follow-up period of 5.7 years. Stress and rest scores from anterior junction, and conventional summed stress score were significantly higher in patients with cardiovascular events than without (all P < 0.05). Anterior junction stress score of >2 produced a sensitivity of 50% and a specificity of 98% for cardiovascular events and was an independent predictor (hazard ratio 8.33; 95% confidence interval, 1.61-43.5; P = 0.01), with rest scores producing similar values, which were higher than summed stress score of >8 (5.68; 1.23-26.3; P = 0.03). The absence of myocardial perfusion abnormality in the narrow area of anterior junction differentiated HCM patients with low-risk.

Topics: Adult; Aged; Atrial Fibrillation; Cardiomyopathy, Hypertrophic; Chi-Square Distribution; Coronary Circulation; Death, Sudden, Cardiac; Disease Progression; Disease-Free Survival; Echocardiography; Exercise Test; Female; Heart Failure; Heart Ventricles; Humans; Kaplan-Meier Estimate; Magnetic Resonance Imaging; Male; Middle Aged; Multivariate Analysis; Myocardial Perfusion Imaging; Organophosphorus Compounds; Organotechnetium Compounds; Predictive Value of Tests; Proportional Hazards Models; Prospective Studies; Radiopharmaceuticals; Risk Assessment; Risk Factors; Sensitivity and Specificity; Stroke; Time Factors; Tomography, Emission-Computed, Single-Photon; Ventricular Septum

The aim of this study was to determine the impact of attenuation correction with CT (CT-AC) on the prognostic value of SPECT myocardial perfusion imaging (SPECT MPI).. The summed stress score (SSS; 20-segment model) was obtained from filtered backprojection (FBP) and iterative reconstruction with CT-AC in 876 consecutive patients undergoing a 1-d stress-rest (99m)Tc-tetrofosmin SPECT MPI study for the evaluation of known or suspected coronary artery disease. Survival free of major adverse cardiac events (MACEs; cardiac death or nonfatal myocardial infarction) and survival free of any adverse cardiac events (including cardiac hospitalization, unstable angina, and late coronary revascularization) were analyzed by Kaplan-Meier analysis.. At a mean follow-up of 2.3 ± 0.6 y, a total of 184 adverse events occurred in 145 patients, including 35 MACEs (16 cardiac deaths [rate, 1.8%] and 19 nonfatal myocardial infarctions [rate, 2.2%]). With FBP, an SSS of 0-3 best distinguished patients with a low MACE rate (0.6%), followed by an SSS of 4-8 (4.3%), with increased MACE rate, and an SSS of 9-13 (3.8%), which was comparable. By contrast, with CT-AC the discrimination of low from intermediate MACE rate was best observed between an SSS of 0 (0%) and an SSS of 1-3 (3.7%), with a plateau at an SSS of 4-8 (3.2%).. CT-AC for SPECT MPI allows improved risk stratification. The prognostically relevant SSS cutoff is shifted toward lower values.

Topics: Adenosine; Aged; Death, Sudden, Cardiac; Disease-Free Survival; Electrocardiography; Endpoint Determination; Female; Follow-Up Studies; Heart; Heart Diseases; Humans; Image Interpretation, Computer-Assisted; Kaplan-Meier Estimate; Male; Middle Aged; Myocardial Infarction; Myocardial Perfusion Imaging; Organophosphorus Compounds; Organotechnetium Compounds; Predictive Value of Tests; Prognosis; Radiopharmaceuticals; Risk Factors; Tomography, Emission-Computed; Tomography, Emission-Computed, Single-Photon; Treatment Outcome

Aims Although cardiac hybrid imaging, 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, no prognostic data exist on the predictive value of cardiac hybrid imaging. Hence, the aim of this study was to assess the prognostic value of hybrid SPECT/CCTA images. Methods and results Of 335 consecutive patients undergoing a 1-day stress/rest (99m)Tc-tetrofosmin SPECT and a CCTA, acquired on stand-alone scanners and fused to obtain cardiac hybrid images, follow-up was obtained in 324 patients (97%). Survival free of all-cause death or non-fatal myocardial infarction (MI) and free of major adverse cardiac events (MACE: death, MI, unstable angina requiring hospitalization, coronary revascularizations) was determined using the Kaplan-Meier method for the following groups: (i) stenosis by CCTA and matching reversible SPECT defect; (ii) unmatched CCTA and SPECT finding; and (iii) normal finding by CCTA and SPECT. Cox's proportional hazard regression was used to identify independent predictors for cardiac events. At a median follow-up of 2.8 years (25th-75th percentile: 1.9-3.6), 69 MACE occurred in 47 patients, including 20 death/MI. A corresponding matched hybrid image finding was associated with a significantly higher death/MI incidence (P < 0.005) and proved to be an independent predictor for MACE. The annual death/MI rate was 6.0, 2.8, and 1.3% for patients with matched, unmatched, and normal findings. Conclusion Cardiac hybrid imaging allows risk stratification in patients with known or suspected CAD. A matched defect on hybrid image is a strong predictor of MACE.

Topics: Aged; Angina, Unstable; Cause of Death; Coronary Angiography; Coronary Artery Disease; Death, Sudden, Cardiac; Female; Hospitalization; Humans; Kaplan-Meier Estimate; Male; Middle Aged; Myocardial Infarction; Myocardial Revascularization; Organophosphorus Compounds; Organotechnetium Compounds; Prognosis; Radiation Dosage; Radiopharmaceuticals; Risk Factors; Tomography, Emission-Computed, Single-Photon; Tomography, X-Ray Computed

Despite widespread prophylactic use of implantable cardioverter defibrillator (ICD) therapy, sudden cardiac death and refractory arrhythmia events are still important clinical issues to be overcome. We examined whether the impairment of cardiac sympathetic innervation and myocardial perfusion is responsible for lethal arrhythmic events and has prognostic value by comparing conventional clinical indices.. In consecutive ICDs implanted in 60 patients, cardiac uptake of (123)I-metaiodobenzylguanidine and (99m)Tc-tetrofosmin at rest was quantified, and then patients were prospectively followed with endpoints of appropriate ICD shocks or cardiac death. Cardiac metaiodobenzylguanidine activity was quantified as a heart-to-mediastinum ratio (HMR), and impaired tetrofosmin uptake was graded as a summed score (SS) using a computerized technique with a percentage of tracer uptake.. During a mean 29-mo interval, ICD shock was documented in 30 patients (50%); 3 cardiac deaths were also observed in this group of patients. Patients with ICD shocks had a significantly smaller HMR and a greater SS than did those without (1.73 +/- 0.34 vs. 2.06 +/- 0.46, P = 0.003, and 18.0 +/- 16.2 vs. 5.7 +/- 4.4, P = 0.001, respectively). Kaplan-Meier analysis showed that patients who had both an HMR of 1.90 or less and an SS of 12 or greater had a significantly greater ICD discharge rate than did those who had both an HMR greater than 1.90 and an SS less than 12 (94% vs. 18%, P < 0.005) (log rank, 15.14; P < 0.0005). Multivariate analysis with a Cox model identified the greatest Wald chi(2) of 6.454 and a hazard ratio of 3.857 (P = 0.011) when an HMR of 1.9 or less and tetrofosmin SS of 12 or greater were combined.. Impairment of cardiac sympathetic innervation and myocardial perfusion is related to lethal arrhythmic events leading to sudden death, and the combined assessment of these can identify patients for whom prophylactic ICD use has the greatest potential.

Topics: 3-Iodobenzylguanidine; Adult; Aged; Analysis of Variance; Arrhythmias, Cardiac; Coronary Circulation; Death, Sudden, Cardiac; Defibrillators, Implantable; Electrocardiography; Endpoint Determination; Female; Follow-Up Studies; Heart; Humans; Kaplan-Meier Estimate; Male; Middle Aged; Organophosphorus Compounds; Organotechnetium Compounds; Prognosis; Proportional Hazards Models; Radiopharmaceuticals; Sympathetic Nervous System; Tomography, Emission-Computed, Single-Photon

We investigated the prognostic value of 99mTc-Tetrofosmin myocardial SPECT (99mTc-TF) in dysfunctional multivessel coronary disease patients who underwent revascularization (RV) or only medical treatment (MT).. In 78 coronary patients with 2-3 diseased vessels and left ventricular ejection fraction (EF) <= 40% (24 10%), we have assessed the extension of the stress perfusion defect, and percent of reversibility (R) by quantification of stress-rest myocardial SPECT 99mTc-TF bull's eyes (2 days-protocol), lung/heart ratio (LH) calculated in the original stress SPECT images, and EF by equilibrium radionuclide ventriculography obtained at 24 h. A R value >= 8% was used to identify viable (V) patients. A total of 28 patients underwent RV and 50 only received MT. After a mean follow-up of 22.9 20 months (3-60), they were considered as coronary events (CE): cardiac death, non-fatal infarction and heart transplant. CE rate was 20.5% (16/78).. No significant differences were found in the pre-revascularization study characteristics, except a significantly higher mean R value in RV (10.6 9.5%) than in MT patients (6.4 7.8%) p: 0.03, and the main difference was that RV patients showed less CE 2/28 (7%) than the MT group 14/50 (28%) p: 0.02. The CE rate was lower in V patients who underwent RV (6%) than in V patients with MT (45%) p: 0.03, but no significant difference was obtained in non-V patients between RV (7%) and MT (16%) groups. In viable patients, the corresponding survival curves (Kaplan-Meier) showed a CE-free survival at 5 years of 79% in patients RV and of 42% in MT patients, p: 0.03, without significant difference in non-V patients.. Patients with viable myocardium by myocardial SPECT have a good prognosis after revascularization, and show higher risk of CE if they are only medically treated. Myocardial viability is an indispensable assessment in prognosis evaluation and, above all, in therapeutic decision making in dysfunctional multivessel coronary disease patients.

Topics: Adult; Aged; Cell Survival; Coronary Circulation; Coronary Disease; Death, Sudden, Cardiac; Exercise Test; Female; Follow-Up Studies; Gated Blood-Pool Imaging; Heart; Heart Transplantation; Humans; Male; Middle Aged; Myocardial Infarction; Myocardial Revascularization; Myocardium; Organophosphorus Compounds; Organotechnetium Compounds; Prognosis; Radiopharmaceuticals; Tomography, Emission-Computed, Single-Photon; Ventricular Dysfunction, Left