914 Atrial and Ventricular Functional Mitral Regurgitation: Clinical Characteristics and Outcomes in Mitraclip Treated Patients

Abstract

Background mitral regurgitation (MR) is the second most common valvular heart disease in Europe. In the contest of functional (or secondary) MR recently has emerged a new entity, the atrial functional MR. This form is due to left atrial dilatation, it has no significant degenerative change in mitral valve complex or significant LV systolic disfunction. Conversely the ventricular functional mitral regurgitation (V-FMR) is due to systolic disfunction and left ventricular dilatation. Aim the aim of this study was to evaluate the differences in clinical characteristics and outcomes of patients with AFMR and VFMR treated with Mitraclip. Methods a retrospective analysis collected consecutive patients with functional MR who underwent transcatheter mitral valve repair using Mitraclip system in our division. A total of 161 patients were divided into the following two categories: VFMR (127 patients), defined as EF<40% or EF ≥40% with history of myocardial infarction, and AFMR (34 patients) identified as EF≥50% and LAVi >48 mL/m2. Baseline and clinical characteristics, echocardiographic parameters and 12 months clinical outcomes (overall mortality at 12 months, MACE at 12 months, re-hospitalization for heart failure (HF), re-hospitalization from other causes at 12 months and number of re-hospitalization at 12 months) were analyzed. Results compared to AFMR, patients with VFMR were younger (73 vs 78 years) had a higher man prevalence (72,4% vs 50%), higher rate of: hypercholesterolemia (79,5% vs 67,6%), smokers (14,2% vs 5,9%), diabetes (39,4% vs 20,6%), chronic kidney disease (55,9% vs 47,1%), NT-proBNP mean value (4403,437 pg/ml vs 2063,409 pg/ml), NYHA class ≥III (84.3 vs 52.9%) and lower rate of hypertension (85% vs 97.1%). In AFMR population there was higher prevalence of atrial fibrillation (70.6% vs 45.7%) and tricuspid valve regurgitation ≥2+ (82.3% vs 68,5%). Moreover, in this group, was lower the all-cause mortality rate at 12 months (9.4 vs 22%), MACE at 12 months (4.5 vs 24.5%), re-hospitalization for HF (15.6% vs 33.1%), re-hospitalization from other causes at 12 months (18.8% vs 31.6%) and number of re-hospitalization at 12 months ≥1 (31,3% vs 59.9%). Conclusion our analysis demonstrated that clinical outcomes at 12 months were lower for the AFMR group. These data are consistent with the literature, where AFMR is considered to have a better prognosis than VFMR, and underline the importance of differentiating these two types of population.