In order to bring you the best possible user experience, this site uses Javascript. If you are seeing this message, it is likely that the Javascript option in your browser is disabled. For optimal viewing of this site, please ensure that Javascript is enabled for your browser.
Did you know that your browser is out of date? To get the best experience using our website we recommend that you upgrade to a newer version. Learn more.

Impact of nuclear cardiology in clinical decision making (Part2)

Review from April until August 2011

Nuclear Imaging
 

About myocardial viability in dysfunctioning myocardium, evaluation of coronary flow reserve, feasibility of evaluation of ischemia with ultrafast SPECT and finally impact of nuclear medicine in women.
N Engl J Med. 2011 Apr 28;364(17):1617-25. Epub 2011 Apr 4.
Bonow RO, Maurer G, Lee KL, et al; STICH Trial Investigators. Myocardial viability and survival in ischemic left ventricular dysfunction.

Read more

In this article, the Authors analyzed the impact of myocardial viability on survival in a population of patients with left ventricular dysfunction randomized to CABG or medical therapy.

In this article, the Authors analyzed the impact of myocardial viability on survival in a population of patients with left ventricular dysfunction randomized to CABG or medical therapy.In this article, the Authors analyzed the impact of myocardial viability on survival in a population of patients with left ventricular dysfunction randomized to CABG or medical therapy.In this article, the Authors analyzed the impact of myocardial viability on survival in a population of patients with left ventricular dysfunction randomized to CABG or medical therapy.

Single-photon-emission computed tomography (SPECT), dobutamine echocardiography, or both were used to assess myocardial viability on the basis of prespecified thresholds.
Among the 1212 patients enrolled in the randomized trial, 601 underwent assessment of myocardial viability. Of these patients, 298 were randomly assigned to receive medical therapy plus CABG and 303 to receive medical therapy alone. A total of 178 of 487 patients with viable myocardium (37%) and 58 of 114 patients without viable myocardium (51%) died (hazard ratio for death among patients with viable myocardium, 0.64; 95% confidence interval [CI], 0.48 to 0.86; P=0.003). However, after adjustment for other baseline variables, this association with mortality was not significant (P=0.21). There was no significant interaction between viability status and treatment assignment with respect to mortality (P=0.53).

The Authors concluded that the presence of viable myocardium was associated with a greater likelihood of survival in patients with coronary artery disease and left ventricular dysfunction, but this relationship was not significant after adjustment for other baseline variables. The assessment of myocardial viability did not identify patients with a differential survival benefit from CABG, as compared with medical therapy alone.

Incremental prognostic value of coronary flow reserve assessed with single-photon emission computed tomography.
J Nucl Cardiol. 2011 Aug;18(4):612-9. Epub 2011 May 28.
Daniele S, Nappi C, Acampa W,  et al. Read more

The Authors assessed the prognostic value of coronary flow reserve (CFR) estimated by single-photon emission computed tomography (SPECT) in patients with suspected myocardial ischemia.

The Authors assessed the prognostic value of coronary flow reserve (CFR) estimated by single-photon emission computed tomography (SPECT) in patients with suspected myocardial ischemia.The Authors assessed the prognostic value of coronary flow reserve (CFR) estimated by single-photon emission computed tomography (SPECT) in patients with suspected myocardial ischemia.

At this purpose, myocardial perfusion and CFR were assessed in 106 patients using dipyridamole/rest Tc-99m sestamibi SPECT and follow-up was obtained in 103 (97%) patients. Four early revascularized patients were excluded and 99 were assigned to normal (summed stress score <3) vs abnormal myocardial perfusion and to normal (≥2.0) vs abnormal CFR. During the follow-up (5.8 ± 2.1 years), 28 patients experienced a cardiac event. Abnormal perfusion (P < .01) and abnormal CFR (P < .05) were independent predictors of cardiac events at Cox proportional hazard regression analysis. Also in patients with normal perfusion, abnormal CFR was associated with a higher annual event rate compared with normal CFR (5.2% vs 0.7%; P < .05). CFR data improved the prognostic power of the model including clinical and myocardial perfusion data increasing the global chi-square from 18.6 to 22.8 (P < .05). Finally, at parametric survival analysis, in patients with normal perfusion the time to achieve ≥2% risk of events was >60 months in those with normal and <12 months in those with abnormal CFR.
In conclusions, myocardial perfusion findings and CFR at SPECT imaging are both independent predictors of cardiac events. Estimated CFR provides incremental prognostic information over those obtained from clinical and myocardial perfusion data, particularly in patients with normal perfusion findings.

Nuclear myocardial perfusion imaging with a novel cadmium-zinc-telluride detector SPECT/CT device: first validation versus invasive coronary angiography
Fiechter M, Ghadri JR, Kuest SM, et al. .
Eur J Nucl Med Mol Imaging. 2011 Jul 15. [Epub ahead of print] . Read more

The Authors evaluated the diagnostic accuracy of attenuation corrected nuclear myocardial perfusion imaging (MPI) with a novel hybrid ultrafast dedicated cardiac gamma camera with cadmium-zinc-telluride (CZT) 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.
The prevalence of angiographic CAD in the study population was 82%. Sensitivity, specificity, positive predictive value, negative predictive value and accuracy were 87, 67, 92, 53 and 83%, respectively.
In conclusions, in this first report on CZT SPECT/CT MPI comparison versus angiography a high accuracy for detection of angiographically documented CAD was confirmed.

The Authors evaluated the diagnostic accuracy of attenuation corrected nuclear myocardial perfusion imaging (MPI) with a novel hybrid ultrafast dedicated cardiac gamma camera with cadmium-zinc-telluride (CZT) 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. The prevalence of angiographic CAD in the study population was 82%. Sensitivity, specificity, positive predictive value, negative predictive value and accuracy were 87, 67, 92, 53 and 83%, respectively.In conclusions, in this first report on CZT SPECT/CT MPI comparison versus angiography a high accuracy for detection of angiographically documented CAD was confirmed.The Authors evaluated the diagnostic accuracy of attenuation corrected nuclear myocardial perfusion imaging (MPI) with a novel hybrid ultrafast dedicated cardiac gamma camera with cadmium-zinc-telluride (CZT) 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. The prevalence of angiographic CAD in the study population was 82%. Sensitivity, specificity, positive predictive value, negative predictive value and accuracy were 87, 67, 92, 53 and 83%, respectively.In conclusions, in this first report on CZT SPECT/CT MPI comparison versus angiography a high accuracy for detection of angiographically documented CAD was confirmed.

Comparative Effectiveness of Exercise Electrocardiography With or Without Myocardial Perfusion Single Photon Emission Computed Tomography in Women With Suspected Coronary Artery Disease: Results From the What Is the Optimal Method for Ischemia Evaluation in Women (WOMEN)
Shaw LJ, Mieres JH, Hendel RH, et al, for the WOMEN Trial Investigators. Trial. Circulation. 2011 Aug 15. [Epub ahead of print] - Read more

Up to now, it remains unclear whether the addition of myocardial perfusion imaging (MPI) to the standard ECG exercise treadmill test (ETT) provides incremental information to improve clinical decision making in women with suspected CAD. To this aim, the Authors randomized symptomatic women with suspected CAD, an interpretable ECG, and ≥5 metabolic equivalents on the Duke Activity Status Index to 1 of 2 diagnostic strategies: ETT or exercise MPI. The primary end point was 2-year incidence of major adverse cardiac events, defined as CAD death or hospitalization for an acute coronary syndrome or heart failure. A total of 824 women were randomized to ETT or exercise MPI. For women randomized to ETT, ECG results were normal in 64%, indeterminate in 16%, and abnormal in 20%. By comparison, the exercise MPI results were normal in 91%, mildly abnormal in 3%, and moderate to severely abnormal in 6%. At 2 years, there was no difference in major adverse cardiac events (98.0% for ETT and 97.7% for MPI; P=0.59). Compared with ETT, index testing costs were higher for exercise MPI (P<0.001), whereas downstream procedural costs were slightly lower (P=0.0008). Overall, the cumulative diagnostic cost savings was 48% for ETT compared with exercise MPI (P<0.001). In conclusions, in low-risk, exercising women, a diagnostic strategy that uses ETT versus exercise MPI yields similar 2-year posttest outcomes while providing significant diagnostic cost savings. The ETT with selective follow-up testing should be considered as the initial diagnostic strategy in symptomatic women with suspected CAD.

Up to now, it remains unclear whether the addition of myocardial perfusion imaging (MPI) to the standard ECG exercise treadmill test (ETT) provides incremental information to improve clinical decision making in women with suspected CAD. To this aim, the Authors randomized symptomatic women with suspected CAD, an interpretable ECG, and ≥5 metabolic equivalents on the Duke Activity Status Index to 1 of 2 diagnostic strategies: ETT or exercise MPI. The primary end point was 2-year incidence of major adverse cardiac events, defined as CAD death or hospitalization for an acute coronary syndrome or heart failure. A total of 824 women were randomized to ETT or exercise MPI. For women randomized to ETT, ECG results were normal in 64%, indeterminate in 16%, and abnormal in 20%. By comparison, the exercise MPI results were normal in 91%, mildly abnormal in 3%, and moderate to severely abnormal in 6%. At 2 years, there was no difference in major adverse cardiac events (98.0% for ETT and 97.7% for MPI; P=0.59). Compared with ETT, index testing costs were higher for exercise MPI (P<0.001), whereas downstream procedural costs were slightly lower (P=0.0008). Overall, the cumulative diagnostic cost savings was 48% for ETT compared with exercise MPI (P<0.001). In conclusions, in low-risk, exercising women, a diagnostic strategy that uses ETT versus exercise MPI yields similar 2-year posttest outcomes while providing significant diagnostic cost savings. The ETT with selective follow-up testing should be considered as the initial diagnostic strategy in symptomatic women with suspected CAD.Up to now, it remains unclear whether the addition of myocardial perfusion imaging (MPI) to the standard ECG exercise treadmill test (ETT) provides incremental information to improve clinical decision making in women with suspected CAD. To this aim, the Authors randomized symptomatic women with suspected CAD, an interpretable ECG, and ≥5 metabolic equivalents on the Duke Activity Status Index to 1 of 2 diagnostic strategies: ETT or exercise MPI. The primary end point was 2-year incidence of major adverse cardiac events, defined as CAD death or hospitalization for an acute coronary syndrome or heart failure. A total of 824 women were randomized to ETT or exercise MPI. For women randomized to ETT, ECG results were normal in 64%, indeterminate in 16%, and abnormal in 20%. By comparison, the exercise MPI results were normal in 91%, mildly abnormal in 3%, and moderate to severely abnormal in 6%. At 2 years, there was no difference in major adverse cardiac events (98.0% for ETT and 97.7% for MPI; P=0.59). Compared with ETT, index testing costs were higher for exercise MPI (P<0.001), whereas downstream procedural costs were slightly lower (P=0.0008). Overall, the cumulative diagnostic cost savings was 48% for ETT compared with exercise MPI (P<0.001). In conclusions, in low-risk, exercising women, a diagnostic strategy that uses ETT versus exercise MPI yields similar 2-year posttest outcomes while providing significant diagnostic cost savings. The ETT with selective follow-up testing should be considered as the initial diagnostic strategy in symptomatic women with suspected CAD.
The content of this article reflects the personal opinion of the author/s and is not necessarily the official position of the European Society of Cardiology.

Contact us