Atrial and ventricular bivalvular functional regurgitation: epidemiology and prognosis

Abstract Introduction Atrial and ventricular phenotypes of functional mitral regurgitation (fMR) and functional tricuspid regurgitation (fTR) have gained importance due to their differential impact on outcome and treatment approaches. Bivalvular functional regurgitation (BVFR), defined as concomitant fMR and fTR, is common, however, little is known about the subtype distribution and associated prognostic implications. The aim of this study was to investigate the incidence and impact of the subtypes of BVFR, and to provide the basis for risk assessment within this heterogenous disease. Methods 1766 patients with ≥ moderate BVFR were included in this study and assigned to three groups: both atrial fMR/ fTR (MA-TA, n=553), both ventricular fMR/ fTR (MV-TV, n =366) and Combined fMR/ fTR (n=847), where one valve had atrial functional regurgitation and the other ventricular functional regurgitation. Results Patients in the MA-TA group were older (median age 76 years) and more often female (53%) than the Combined (median age 74 years, 34% female) and MV-TV groups (median age 70 years, 14% female). Per definition, all patients with MA-TA had preserved left ventricular (LV) function and right ventricular (RV) function. In the Combined group, most patients had reduced LV function (73%) and only a small portion exhibited ≥ moderate RV dysfunction (12%). In the MV-TV group, 72% of patients had LV- and 98% RV dysfunction. A marked dilatation of the LA and RA was observed across all three subtypes, however, the MV-TV cohort had the most pronounced enlargement of the atria. After eight years, 35% in the MA-TA group, 44% in the Combined group, and 49% in the MV-TV group had died. In comparison to MA-TA, the Combined group had a hazard ratio [HR] of 1.35 (95% confidence interval [CI]: 1.14–1.61, p < 0.001) and MV-TV had a HR of 1.85 (95% CI: 1.51–2.27, p < 0.001), as depicted in Figure 1. These findings remained virtually unchanged after multivariable adjustment for traditional clinical risk factors (Table 1). Conclusions BVFR most commonly appears as the Combined subtype, followed by MA-TA with MV-TV being the smallest BVFR subtype. Patients with MV-TV have significantly worse outcomes when compared to the Combined and MA-TA subtypes- a phenomenon persisting throughout long-term survival analysis and uni- and multivariable analysis. Further research is necessary to determine whether this BVFR subtype might benefit particularly from interventional treatment.Kaplan-Meier survival analysis Cox regression models