Functional capacity by cardiopulmonary exercise testing is not related to health status in obstructive hypertrophic cardiomyopathy

Abstract Background In obstructive hypertrophic cardiomyopathy (HCM), the primary goal of therapy is to improve patient quality of life by decreasing symptom burden. Increasingly, cardiopulmonary exercise testing (CPET), with peak oxygen consumption (pVO2) and ventilator efficacy (VE/VCO2), is used to assess efficacy of novel therapies in clinical studies and selectively in clinical practice to determine treatments. However, the relationship of CPET variables to symptom burden in HCM is not well established. Therefore, we examined the relationship between CPET variables and health status measured by Kansas City Cardiomyopathy Questionnaire (KCCQ) and NYHA functional classification in a cohort of obstructive HCM patients. Methods Consecutive patients with HCM and resting left ventricular outflow tract (LVOT) obstruction (≥50 mmHg) underwent CPET between October 2022 to January 2024. Patients with a peak RER