15-Year outcome after normal exercise Tc-99m-sestamibi myocardial perfusion imaging: What is the duration of low risk after a normal scan?

The goal of this study was to evaluate the very long-term outcome after normal exercise Tc-99m-sestamibi myocardial perfusion single-photon emission computed tomography (SPECT). Exercise Tc-99m-sestamibi SPECT is widely used for risk stratification, but data on very long-term outcome after a normal test are scarce. A consecutive group of 233 patients (122 men, mean age 54 +/- A 12 years) with known or suspected coronary artery disease (CAD) underwent exercise Tc-99m-sestamibi SPECT and had normal myocardial perfusion at exercise and at rest. Follow-up endpoints were all-cause mortality, cardiac mortality, nonfatal myocardial infarction, and coronary revascularization. Predictors of outcome were identified by Cox proportional hazard regression models using clinical and exercise testing variables. During a mean follow-up of 15.5 +/- A 4.9 years, 41 (18%) patients died, of which 13 were cardiac deaths. A total of 18 (8%) patients had a nonfatal myocardial infarction, and 47 (20%) had coronary revascularization. The annualized event rates for all-cause mortality, cardiac mortality, cardiac mortality/nonfatal infarction, and major adverse cardiac events were, respectively, 1.1%, 0.3%, 0.7%, and 1.8%. Multivariate analysis demonstrated that the variables age, male gender, diabetes, diastolic Patients with suspected or known CAD and normal exercise Tc-99m-sestamibi myocardial perfusion SPECT have a favorable 15-year prognosis. Follow-up should be closer in patients with known CAD, and/or having clinical and exercise parameters indicating higher risk status.