Impact of extra-mitral valve cardiac involvement in patients with primary mitral regurgitation undergoing transcatheter edge-to-edge repair.

BACKGROUND: In the context of primary mitral regurgitation (PMR), the selection of patients for transcatheter edge-to-edge repair (TEER) does not include a systematic assessment of PMR-associated cardiac remodelling. AIMS: We aimed to investigate the epidemiology and prognostic significance of different phenotypes of extra-mitral valve (MV) cardiac involvement in a large series of patients with PMR referred for TEER. METHODS: The study included 654 patients from the multicentre Italian GIOTTO registry, stratified into groups according to extra-mitral valve (MV) cardiac involvement. The primary endpoint was all-cause death at 2-year follow-up. RESULTS: Patients with no cardiac involvement (NI; n=58), left heart involvement (LHI; n=343) and right heart involvement (RHI; n=253) were analysed. Acute technical success was achieved in 98% of patients. Kaplan-Meier curve analysis revealed significantly worse survival in patients with LHI and RHI (p=0.041). On multivariate Cox regression analysis, extra-MV cardiac involvement, haemoglobin level and technical success were independent predictors of the primary endpoint occurrence. CONCLUSIONS: Grading cardiac involvement may help refine risk stratification, since at least 1 group of extra-MV cardiac involvement represents in itself a negative predictor of midterm outcome.

Prediction of mortality and heart failure hospitalisations in patients undergoing M-TEER: external validation of the COAPT risk score.

BACKGROUND: A risk score was recently derived from the Cardiovascular Outcomes Assessment of the MitraClip Percutaneous Therapy for Heart Failure Patients with Functional Mitral Regurgitation (COAPT) Trial. However, external validation of this score is still lacking. AIMS: We aimed to validate the COAPT risk score in a large multicentre population undergoing mitral transcatheter edge-to-edge repair (M-TEER) for secondary mitral regurgitation (SMR). METHODS: The Italian Society of Interventional Cardiology (GIse) Registry of Transcatheter Treatment of Mitral Valve RegurgitaTiOn (GIOTTO) population was stratified according to COAPT score quartiles. The performance of the COAPT score for 2-year all-cause death or heart failure (HF) hospitalisation was evaluated in the overall population and in patients with or without a COAPT-like profile. RESULTS: Among the 1,659 patients included in the GIOTTO registry, 934 had SMR and complete data for a COAPT risk score calculation. The incidence of 2-year all-cause death or HF hospitalisation progressively increased through the COAPT score quartiles in the overall population (26.4% vs 44.5% vs 49.4% vs 59.7%; log-rank p<0.001) and COAPT-like patients (24.7% vs 32.4% vs 52.3% vs. 53.4%; log-rank p=0.004), but not in those with a non-COAPT-like profile. The COAPT risk score had poor discrimination and good calibration in the overall population, moderate discrimination and good calibration in COAPT-like patients and very poor discrimination and poor calibration in non-COAPT-like patients. CONCLUSIONS: The COAPT risk score has a poor performance in the prognostic stratification of real-world patients undergoing M-TEER. However, after application to patients with a COAPT-like profile, moderate discrimination and good calibration were observed.

Acute changes in mitral valve geometry after percutaneous valve repair with MitraClip XTR by three-dimensional echocardiography.

BACKGROUND: Mitral valve (MV) repair with MitraClip system is a safe treatment option for high-risk patients with significant mitral regurgitation (MR). We aimed to characterize, by three-dimensional echocardiography (3D-E), changes occurring in MV after implantation of third generation MitraClip XTR device, with specific reference to the underlying MR mechanism (functional vs degenerative, FMR vs DMR). METHODS: We prospectively enrolled 59 patients, who underwent intra-procedural 3D-E before and after device deployment. Three-D datasets were analyzed off-line, using a dedicated semiautomatic software, to obtain parametric quantification of mitral anatomy. RESULTS: Post-procedural MR of mild or lesser degree was achieved in 40 patients (68%), with no differences between FMR and DMR (p 0.9). After MitraClip XTR implantation, the FMR group experienced an immediate annular resizing, with reduction of antero-posterior diameter (p 0.024) and sphericity index (p 0.017), next to a recovery of physiological saddle-shape, defined by lower non-planar angle (p ≤0.001) and higher annulus height to commissural width ratio (p ≤0.001). On the opposite, the DMR group revealed a significant decrease of maximum annular velocity (p 0.027), addressing a mechanic effect of the device deployment. Finally, baseline anterior mitral leaflet angle was found as an independent predictor of acute procedural result (OR 6.7, [CI 1.01-44.33], p 0.049). CONCLUSIONS: MitraClip XTR implantation acts in restoring the original mitral geometry, with distinctive effects according to MR mechanism. Three-D parametric quantification of MV sheds new light on changes occurring in the valvular apparatus, and helps identifying possible new predictors of acute procedural success.