Hypercontractile phenotype in hypertrophic cardiomyopathy indicates unfavorable hemodynamics, coronary flow and prognosis

Abstract

AIMS: Our aim was to assess the clinical and prognostic significance of the left ventricular (LV) hypercontractile phenotype (HP) in hypertrophic cardiomyopathy (HCM), which until now remains unclear. METHODS AND RESULTS: We enrolled 1533 HCM patients (age 51 ± 15 years, 965 males, 63%) with ejection fraction (EF) ≥ 50%, referred for rest transthoracic echocardiography (TTE) in 27 laboratories from 13 countries. Two-dimensional volumetric TTE assessment included LV outflow tract gradient (LVOTG), LV EF, and LV force (systolic blood pressure + LVOTG/ESV, mmHg/mL). HP was defined as the highest quartile of the force (> 7.32 mmHg/mL). Survival analysis was performed in a subset of 1200 patients with follow-up information. Compared with non-HP patients, HP showed higher heart rate (72 ± 14 vs. 67 ± 14 beats per minute, P 7.32 mmHg (the fourth quartile for analyzed patients) was associated with a hazard ratio of 1.44 (95% Confidence intervals 1.00-2.07) for all-cause death, independently of LVOTG and LV EF. CONCLUSION: HP in HCM is associated with a disadvantageous systemic, cardiac and coronary hemodynamic profile as well as lower survival in the long-term.