The safety of cardiopulmonary exercise testing in a population with high-risk cardiovascular diseases

BACKGROUND: Cardiopulmonary exercise testing (CPX) with measurement of peak oxygen uptake (VO2) is a powerful test for assessment and quantification of functional impairment resulting from cardiovascular disease. The safety of CPX has been established in patients with coronary artery disease and congestive heart failure, but clinical use of CPX in other cardiac diseases has been limited, in part because of a paucity of safety data. This study investigates the safety of CPX in a heterogeneous cohort of patients with a wide variety of underlying high-risk cardiac diagnoses. METHODS AND RESULTS: This single-center retrospective review examined 5060 CPX studies performed in 4250 unique patients, including 1748 (35%) female subjects and 686 (14%) subjects aged 75 years. The primary end point was major adverse event during stress testing. The study population included patients with a variety of high-risk cardiac diseases, including congestive heart failure (n=1289, 25.5%), hypertrophic cardiomyopathy (n=598, 11.8%), pulmonary hypertension (n=194, 3.8%), and aortic stenosis (n=212, 4.2%). This patient population generally had severe functional impairment, including 1192 (24%) patients with peak VO2<14 mL/kg/min. Eight adverse events occurred during CPX, for an adverse event rate of 0.16%. The most common adverse event (n=6) was sustained ventricular tachycardia. There were no fatal events. CONCLUSIONS: CPX is generally a safe procedure, even in a population with underlying high-risk cardiovascular diagnoses.