Obesity Modifies Clinical Outcomes of Right Ventricular Dysfunction

Abstract

BACKGROUND: Right ventricular (RV) dysfunction is associated with increased mortality across a spectrum of cardiovascular diseases. The role of obesity in RV dysfunction and adverse outcomes is unclear. METHODS: We examined patients undergoing right heart catheterization between 2005 and 2016 in a hospital-based cohort. Linear regression was used to examine the association of obesity with hemodynamic indices of RV dysfunction (pulmonary artery pulsatility index, right atrial pressure:pulmonary capillary wedge pressure ratio, RV stroke work index). Cox models were used to examine the association of RV function measures with clinical outcomes. RESULTS: Among 8285 patients (mean age, 63 years; 40% women), higher body mass index was associated with worse indices of RV dysfunction, including lower pulmonary artery pulsatility index (β, −0.23; SE, 0.01; P <0.001), higher right atrium:pulmonary capillary wedge pressure ratio (β, 0.25; SE, 0.01; P <0.001), and lower RV stroke work index (β, −0.05; SE, 0.01; P <0.001). Over median of 7.3 years of follow-up, we observed 3006 mortality and 2004 heart failure hospitalization events. RV dysfunction was associated with a greater risk of mortality (eg, pulmonary artery pulsatility index:hazard ratio, 1.11 per 1-SD increase [95% CI, 1.04–1.18]), with similar associations with risk of heart failure hospitalization. Body mass index modified the effect of RV dysfunction on all-cause mortality ( P interaction ≤0.005 for PAPi and RA:PCWP ratio), such that the effect of RV dysfunction was more pronounced at higher body mass index. CONCLUSIONS: Patients with obesity had worse hemodynamic measured indices of RV function across a broad hospital-based sample. While RV dysfunction was associated with worse clinical outcomes including mortality and heart failure hospitalization, this association was especially pronounced among individuals with higher body mass index.