PROGNOSTIC VALUE OF EXERCISE RADIONUCLIDE ANGIOGRAPHY IN A POPULATION-BASED COHORT OF PATIENTS WITH KNOWN OR SUSPECTED CORONARY-ARTERY DISEASE

Five hundred thirty-six residents of Olmsted County, Minnesota, who un derwent supine vest and exercise radionuclide angiography because of k nown or suspected coronary artery disease, were followed for a median of 46 months to determine the prognostic value of exercise radionuclid e angiography in a community population who generally did not undergo coronary angiography. There were 71 persons who experienced a new card iac event (the initial events were cardiac death and nonfatal myocardi al infarction in 26 and 45 persons, respectively). A propartional haza rds model identified 4 independent predictors of cardiac events: exerc ise ejection fraction (p < 0.001), exercise heart rate (p < 0.001), hi story of myocardial infarction (p = 0.01), and age (p = 0.04). Four-ye ar infarct free survival was 98% for the 152 patients with a peak exer cise heart rate at or above the median (122 beats/min) and an exercise ejection fraction at or above the median (0.58). In the 150 patients with a peak exercise heart rate < 122 beats/min and an exercise ejecti on fraction < 0.58, 4-year infarct-free survival was 68%. when this po pulation-based cohort was compared with a referral case series previou sly reported from our institution, these population based patients wer e significantly more likely to be men, to have typical angina, to have higher exercise heart rates and exercise ejection fractions, and were less likely to be receiving beta-receptor antagonist therapy. At each level of exercise ejection fraction, the population based patients ha d a slightly but insignificantly greater risk than referral patients f or subsequent cardiac events. These population-based data provide stro ng evidence of the prognostic value of exercise radionuclide angiograp hy in community practice.