Outcomes after normal dobutamine stress echocardiography and predictors of adverse events: Long-term follow-up of 3014 patients

Aims: Normal exercise echocardiography predicts a good prognosis. Dobutamine stress echocardiography (DSE) is generally reserved for patients with comorbidities which preclude exercise testing. We evaluated predictors of adverse events after normal DSE. Methods and results: We studied 3014 patients (1200 males, 68±12 years) with normal DSE, defined as the absence of wall motion abnormality at rest or with stress. During median follow-up of 6.3 years, all-cause mortality and cardiac events, defined as myocardial infarction and coronary revascularization, occurred in 920 (31%) and 231 (7.7%) patients, respectively. Survival and cardiac event-free probabilities were 95 and 98% at 1 year, 78 and 93% at 5 years, and 56 and 89% at 10 years, respectively. Age, diabetes mellitus, and failure to achieve 85% age-predicted maximal heart rate were independent predictors of mortality and cardiac events. Patients with all three of these characteristics had a 13% probability of cardiac events within the first year and higher risk throughout follow-up. Conclusion: Prognosis after normal DSE is not necessarily benign, but depends on patient and stress test characteristics. Careful evaluation, using clinical and stress data, is required to identify patients with normal DSE who are at increased risk of adverse outcomes during long-term follow-up.