Relation of left ventricular diastolic function to LV structure and outcomes in patients with aortic regurgitation

Aims This study aimed to investigate the relationship between diastolic dysfunction (DD) and extracellular volume (ECV), scar burden, and myocyte volume in patients with at least moderate aortic regurgitation (AR) by cardiac magnetic resonance (CMR). We also sought to determine the association of DD with mortality in AR patients. Methods and results Patients with at least moderate AR and who underwent echocardiographic and CMR imaging with a median time of 4 days between the two studies (interquartile range 1-43 days) were included. CMR was used to obtain left ventricular (LV) volumes, ejection fraction and mass, AR severity, scar extent, and ECV. DD was assessed by comprehensive echocardiography. The study included 323 patients. The mean age was 61.9 ± 16.0 and the median follow-up was 3.8 years, during which 86 patients died and 69 were hospitalized for heart failure. LV end-systolic volume, LV mass index, ECV, indexed cellular volume, and scar burden increased with advanced DD (P < 0.01). In multivariable Cox proportional hazard models, Grades II and III DD were independently associated with increased mortality (HR = 1.49, 95% CI = 1.1-1.98, P = 0.009). Conclusion ECV, scar, and myocyte volume by CMR progressively increase with higher grades of DD by echocardiography, and DD is independently associated with mortality in patients with at least moderate AR.