Safety of symptom-limited cardiopulmonary exercise testing in patients with chronic heart failure due to severe left ventricular systolic dysfunction

Background To assess the safety of symptom-limited exercise testing in patients with New York Heart Association class II-IV heart failure symptoms due to left ventricular systolic dysfunction, we investigated the frequency of all-cause fatal and nonfatal major cardiovascular (CV) events among subjects enrolled in a prospective clinical trial (HF-ACTION). We hypothesized that exercise testing would be safe, as defined by a rate for all-cause death of