Heart failure progression in hypertrophic cardiomyopathy - Possible insights from cardiopulmonary exercise testing

Background: Heart failure (HF) progression and its complications represent major emergent concerns in hypertrophic cardiomyopathy (HCM). We investigated the possible adjunctive role of cardiopulmonary exercise testing (CPET) in predicting HF-related events. An exercise-derived risk model, the HYPertrophic Exercise-derived Risk HF (HYPER_HF), has been developed. Methods and Results: A multicenter cohort of 620 consecutive HCM outpatients was recruited and followed (2007 to 2015). The endpoint was death from HF, cardiac transplantation, NYHA III–IV class progression, severe functional deterioration leading to hospitalization for septal reduction, and hospitalization for HF worsening. During a median follow-up of 3.8 years (25–75th centile: 2.3–5.3 years), 84 patients reached the endpoint. Peak circulatory power (peak oxygen consumption * peak systolic blood pressure), ventilatory efficiency and left atrial diameter were independently associated with the endpoint and, accordingly, integrated into the HYPER_HF model (C index: 0.849; best cutoff value equal to 15%). Conclusions: CPET is useful in the evaluation of HCM patients. In this context, the HYPER_HF score might allow early identification of those patients at high risk of HF progression and its complications.