Background: Octogenarian patients referred for stress myocardial perfusion imaging (MPI) differ from younger (non-octogenarian) patients in that they have lower prevalence of risk factors for CAD, but more frequent ischemic events and higher cardiac mortality.
Hypothesis: The purpose of this study was to investigate the efficacy of MPI in octogenarian men and women compared with that in the younger population, and to compare the prognostic value of stress MPI in both populations.
Methods: We studied 162 consecutive patients aged > or = 80 years who were referred for stress MPI, and compared them with 253 consecutive patients aged < 80 years. Patients completed a questionnaire encompassing information about the existence of coronary risk factors, cardiac symptoms, coronary artery disease (CAD), myocardial infarction, coronary artery bypass graft, percutaneous transluminal coronary angioplasty, and results of stress MPI. The patients were followed up for cardiac mortality for a mean of 45 +/- 12 months.
Results: There were 61 women and 101 men (17% of all referrals) with a mean age of 83 +/- 3 (range 80-90). Parameters of octogenarian patients demonstrated a significantly lower prevalence of non-insulin-dependent diabetes mellitus (p < 0.02), hypercholestrolemia (p < 0.001), and smoking (p = 0.001) compared with non-octogenarian patients. The prevalence of known CAD was similar, but the prevalence of abnormal resting electrocardiogram, left ventricular (LV) dilatation, and stress-induced ischemia was significantly higher in octogenarians (p < 0.002). Cardiac mortality rate per year was 4.3% in octogenarians versus 1.3% in the younger population (p < 0.0001). The independent predictors according to MPI of cardiac death were LV dilatation and presence of ischemia in octogenarians, and severity of ischemia in non-octogenarians.
Conclusions: The octogenarian population referred for stress single-photon emission computed tomography differed from the non-octogenarian group in that it had a lower prevalence of risk factors for CAD, but more frequent ischemic events and higher cardiac mortality; however, MPI variables predict adverse outcome in both populations.