Left ventricular hypertrophy in severe primary mitral regurgitation increases risk of cardiovascular death and heart failure hospitalization (HR 2.52) over 4.5 years.
Does the presence of left ventricular hypertrophy increase the risk of cardiovascular mortality and heart failure hospitalization in patients with severe primary mitral regurgitation?
In patients with severe primary mitral regurgitation, the presence of left ventricular hypertrophy is associated with a 2.5-fold increased risk of cardiovascular mortality or heart failure hospitalization.
Absolute Event Rate: 0% vs 0%
Abstract Background Left ventricular hypertrophy (LVH) is a compensatory response to volume overload in mitral regurgitation to maintain ejection fraction (LVEF). However, over time, this adaptive response is likely to decompensate, ultimately leading to a decline in systolic function. Purpose As the impact of left ventricular mass index (LVMi) in severe primary mitral regurgitation remains poorly defined, we aimed to clarify how increasing LVMi influences systolic function and outcomes. Methods Patients from a tertiary cardiovascular referral centre with consecutive index echocardiographic diagnoses (2010-2020) of severe primary MR were included. Exclusion criteria were previous myocardial infarction, prior percutaneous coronary intervention/coronary artery bypass graft, or missing data on LVMi, relative wall thickness (RWT) and LVEF. Patients were stratified based on the presence of LVH (115 g/m2 for males and 95 g/m2 for females). To assess the relationship between LVEF and LVMi whilst allowing for potential non-linearity, we fitted an adjusted ordinary least squares regression model using a restricted cubic spline with four knots, adjusting for age, sex, RWT, indexed left atrial diameter and hypertension. Predictors of LVH were identified via logistic regression. The primary composite outcome of cardiovascular mortality and first heart failure hospitalization was assessed using Cox regression and restricted mean survival ratios (RMSR). Sensitivity analysis was performed via eccentric and concentric LVH subgroups (RWT ≤0.42 and 0.42 respectively). Results A total of 404 patients were included. Patients with LVH had higher BMI, presented with higher NYHA functional class III/IV, had lower LVEF and larger indexed left atrial diameters. There was no difference in RWT between patients with or without LVH. We observed a significant negative non-linear association between LVEF and LVMi (β = -0.40, P = 0.015), although the spline curve initially showed an increase in LVEF at lower LVMi values. Of note, the second derivative of the spline term suggests that the rate of decline in LVEF may decrease at higher LVMi levels (β = 1.02, P = 0.035). Independent predictors of LVH included hypertension, larger indexed LV end diastolic diameter, and LVEF 60%. Over a median follow-up of 4.52 years (interquartile range 2.72 to 6.64), the presence of LVH was associated with a greater risk of the primary composite outcome (HR 2.52, 95% CI 1.04 to 6.09) and poorer event-free survival at 5 years (RMSR 0.92, 95% CI 0.87 to 0.98) after adjusting for baseline and clinical characteristics. The direction and significance of results were consistent for both eccentric and concentric LVH, though no difference in mortality risk/event-free survival was observed for concentric LVH (n=88). Conclusion(s) A higher LVMi may be associated with systolic dysfunction, an increased risk for cardiovascular mortality and first heart failure hospitalization in patients with severe primary MR.Spline of LVEF against LVMi KM curve for composite outcome
Wong et al. (Sat,) reported a other. Left ventricular hypertrophy in severe primary mitral regurgitation increases risk of cardiovascular death and heart failure hospitalization (HR 2.52) over 4.5 years.