Abstract
The ideal phenotype of patients with functional mitral regurgitation (FMR) who benefit most of transcatheter edge-to-edge repair (TEER) is still unclear. Some studies have suggested that patients with disproportionate FMR may have a better outcome. The purpose of this study is to evaluate the prognostic value of proportionate versus disproportionate FMR, in patients undergoing TEER with MitraClip system.
The multicenter observational MITRA-CTV registry includes 200 patients with moderate-severe (3+) to severe (4+) FMR undergoing MitraClip, between March 2013 and June 2021, at three European institutions such as Magna Graecia University of Catanzaro, University of Turin (Italy) and University of Vigo (Spain). Patients were defined as having proportionate or disproportionate FMR if their EROA/LVEDV (left ventricular end diastolic volume) ratio was ≤ or > from the median value (0.15), respectively. The primary endpoint was the composite of death from all causes and rehospitalizations for HF, at 1-year follow-up. The secondary endpoint was composed of the individual components of the primary endpoint and cardiovascular death. Patients with disproportionate FMR had higher EROA (0.47±0.2 cm2 vs 0.27±0.1 cm2) and smaller ventricles (LVEDV: 207 ± ml vs 239 ± 83 ml) than those with proportionate FMR. Procedural success was achieved in 95% of patients. Notably, 30-day residual MR was comparable in patients with disproportionate versus proportionate FMR. There were 4 (2%) deaths during hospitalization, and the median hospital stay after the procedure was 9 days (IQR 7- 9 days). At Kaplan-Meier analysis, an EROA/LVEDV ratio both higher and lower than the median value (0.15) was not associated with an increased incidence of the primary endpoint of death and rehospitalization for HF (HR 1.17 CI 95%[0.72;1.90],p=0.50). The only independent predictors of clinical outcomes at 1 year were: the presence of CKD (HR 4.11 95% CI[1.73;9.75], p=0.0014) and a post TMVR hospital stay >10 days (HR 2.53 95% CI[1.24;5.18],p=0.0111).
In our study, there were no significant differences in outcome in patients with proportionate versus proportionate FMR undergoing TEER with Mitraclip system.
