Prognostic Implications of Left Ventricular Dilation in Patients With Nonischemic Heart Failure: Interactions With Restrictive Filling Pattern and Mitral Regurgitation

The aim of this study was to evaluate whether small left ventricular (LV) volumes increase the negative prognostic impact of a restrictive filling pattern (RFP) and that of mitral regurgitation (MR) in patients with nonischemic heart failure (HF). The Meta-analysis Research Group in Echocardiography (MeRGE) is a meta-analysis that collated individual patient data from several prospective echocardiography outcome studies. This analysis was restricted to 10 studies and 601 patients with nonischemic HF. The role of MR was tested in a subgroup of 252 patients. A total of 106 deaths occurred during a median follow-up of 32 months. At multivariate analysis, RFP (hazard ratio [HR], 4.16; 95% confidence interval [CI], 1.54-11.23; P=.005) and New York Heart Association class III or IV (HR, 2.15; 95% CI, 1.33-3.47; P=.001) were the independent predictors of poor prognosis, and there was no statistically significant interaction between LV dilation and RFP. Moderate/severe MR was associated with poorer outcome in the group of patients with normal volumes, whereas it was not a significant predictor of mortality in patients with any degree of LV dilation. In patients with nonischemic HF, RFP is the most important indicator of poor prognosis, irrespective of the degree of LV dilation. Normal LV volumes increase the negative prognostic impact of moderate to severe MR.