Prognostic value of stress myocardial perfusion positron emission tomography: results from a multicenter observational registry

Abstract

Objectives: The primary objective of this multicenter registry was to study the prognostic value of positron emission tomography (PET) myocardial perfusion imaging (MPI) and the improved classification of risk in a large cohort of patients with suspected or known coronary artery disease (CAD).

Background: Limited prognostic data are available for MPI with PET.

Methods: A total of 7,061 patients from 4 centers underwent a clinically indicated rest/stress rubidium-82 PET MPI, with a median follow-up of 2.2 years. The primary outcome of this study was cardiac death (n = 169), and the secondary outcome was all-cause death (n = 570). Net reclassification improvement (NRI) and integrated discrimination analyses were performed.

Results: Risk-adjusted hazard of cardiac death increased with each 10% myocardium abnormal with mildly, moderately, or severely abnormal stress PET (hazard ratio [HR]: 2.3 [95% CI: 1.4 to 3.8; p = 0.001], HR: 4.2 [95% CI: 2.3 to 7.5; p < 0.001], and HR: 4.9 [95% CI: 2.5 to 9.6; p < 0.0001], respectively [normal MPI: referent]). Addition of percent myocardium ischemic and percent myocardium scarred to clinical information (age, female sex, body mass index, history of hypertension, diabetes, dyslipidemia, smoking, angina, beta-blocker use, prior revascularization, and resting heart rate) improved the model performance (C-statistic 0.805 [95% CI: 0.772 to 0.838] to 0.839 [95% CI: 0.809 to 0.869]) and risk reclassification for cardiac death (NRI 0.116 [95% CI: 0.021 to 0.210]), with smaller improvements in risk assessment for all-cause death.

Conclusions: In patients with known or suspected CAD, the extent and severity of ischemia and scar on PET MPI provided powerful and incremental risk estimates of cardiac death and all-cause death compared with traditional coronary risk factors.

Copyright © 2013 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.

Figures

Figure 1. Unadjusted Hazard of Events by % Abnormal Myocardium on Vasodilator Stress Rb-82 PET

Hazard of cardiac-death (A, 6, 037 patients, N= 169 cardiac-deaths) and all-cause death (B, 7,061 patients, N=570 all-cause deaths) was lowest in patients with normal PET MPI and increased gradually in patients with minimal, mild, moderate or severe degrees of scan abnormality.

Figure 1. Unadjusted Hazard of Events by % Abnormal Myocardium on Vasodilator Stress Rb-82 PET

Hazard of cardiac-death (A, 6, 037 patients, N= 169 cardiac-deaths) and all-cause death (B, 7,061 patients, N=570 all-cause deaths) was lowest in patients with normal PET MPI and increased gradually in patients with minimal, mild, moderate or severe degrees of scan abnormality.

Figure 2. Risk-Adjusted Hazard of Events by % Abnormal Myocardium on Vasodilator Stress Rb-82 PET

Hazard of cardiac-death (A, 6, 037 patients, N= 169 cardiac-deaths)and all-cause death (B, 7,061 patients, N=570 all-cause deaths) was lowest in patients with normal PET MPI and increased gradually in patients with minimal, mild, moderate or severe degrees of scan abnormality.

Figure 2. Risk-Adjusted Hazard of Events by % Abnormal Myocardium on Vasodilator Stress Rb-82 PET

Hazard of cardiac-death (A, 6, 037 patients, N= 169 cardiac-deaths)and all-cause death (B, 7,061 patients, N=570 all-cause deaths) was lowest in patients with normal PET MPI and increased gradually in patients with minimal, mild, moderate or severe degrees of scan abnormality.