As the age of the population is increasing worldwide, it is important to have data on stress echocardiography in very old patients. When these patients have suspected or known coronary artery disease are often referred for pharmacological stress testing. Data on the value of exercise echocardiography (ExE) for predicting outcome in these patients are scarce.
Methods: From our stress echocardiography databank, we selected patients aged ≥80 years of age with known or suspected coronary artery disease. Among 538 patients with these characteristics, we excluded 41 (7.6%) who were submitted to pharmacological stress, and consider 497 patients (92.4%) in whom a treadmill ExE was performed. A maximal test was considered when ≥85% of the maximal age-predicted heart rate was achieved. Left ventricular (LV) function was evaluated at baseline and with exercise, and the increases in wall motion score index (ΔWMSI) and in LV ejection fraction (ΔLVEF) from rest to peak exercise were calculated. Ischaemia was diagnosed when new or worsening wall motion abnormalities developed with exercise. The end points were major cardiac events (cardiac death or myocardial infarction before any revascularization procedure) and all-cause mortality.
Results: Protocols employed were the Bruce in 70.6% of the patients and modified protocols in the rest (29.4%). Achieved workload in metabolic equivalents was 6.2±2.3 and a maximal test was obtained in 73% of the patients. Ischaemia developed in 184 patients (37%) during exercise. Over a mean follow-up of 2.9±3.2 years, 78 major cardiac events and 184 deaths occurred. Annualized major cardiac event rates were 5.7% in patients without ischaemia versus 9.2% in those with ischaemia (P=0.02). After covariate adjustment, either ΔLVEF or ΔWMSI remained independent predictors of major cardiac events (ΔLVEF: hazard ratio [HR] 0.96, 95% confidence interval [CI] 0.93–0.99, P=0.005; ΔWMSI: HR 2.56, 95% CI 1.20–5.48, P=0.015). When added to a model with clinical, resting echocardiographic and exercise electrocardiogram variables, ExEcho results provided incremental value for the prediction of major cardiac events (P=0.009). Although the ExE parameters were not predictive of mortality after adjustment, exercise testing parameters were: metabolic equivalents (HR 0.89, 95% CI 0.84–0.85, p<0.001).
Conclusions: Treadmill ExE is feasible in most octogenarians with suspected or known coronary artery disease and provides useful information for risk stratification.