Impact of eccentric jet on outcomes in patients with atrial functional mitral regurgitation: An echocardiographic...

Previous studies have reported the mechanisms underlying atrial functional mitral regurgitation (A-FMR). Recently, A-FMR subtypes based on mitral regurgitation (MR) mechanisms were proposed: "central jet" due to insufficient leaflet remodeling and "eccentric jet" due to atriogenic tethering. However, their prognostic value remains unclear. Therefore, this study investigated the impact of A-FMR subtypes on clinical outcomes.

Outpatients with significant A-FMR between January 2013 and December 2016 were retrospectively reviewed. They were classified into two subtypes according to the MR jet's direction. All-cause mortality, heart failure hospitalization, and any mitral valve interventions were the primary composite endpoint.

Among 101 patients with significant A-FMR, 32% had eccentric jet. The primary endpoint was observed in 56 patients during the follow-up period (median 0.7 years, range 0.1-4.2 years). Kaplan-Meier curves demonstrated that the composite endpoint was higher among patients with eccentric jet than those with central jet (log-rank p < 0.001). Eccentric jet (hazard ratio [HR] 2.46, 95% confidence interval [CI] 1.28-4.73; p = 0.007), age (HR 1.06, 95% CI 1.02-1.11; p = 0.002), symptoms (HR 6.22, 95% CI 2.18-17.8; p < 0.001), severe MR (HR 3.97, 95% CI 1.92-8.18; p < 0.001), and significant tricuspid regurgitation (TR; HR 2.00, 95% CI 1.01-3.97; p = 0.047) were independent predictors of the composite endpoint.

Patients with eccentric jet had poorer outcomes than those with central jet. Eccentric jet, age, symptoms, severe MR, and significant TR were independently associated with poor outcomes.