One-Year Outcomes of M-TEER With the PASCAL System in Atrial and Ventricular FMR: Insights From the MiCLASP Postmarket Clinical Follow-Up Study.

Background

Studies on mitral transcatheter edge-to-edge repair for atrial functional mitral regurgitation (AFMR) and ventricular functional mitral regurgitation (VFMR) are limited.

Methods

We report 1-year outcomes of mitral transcatheter edge-to-edge repair for AFMR and VFMR using the PASCAL transcatheter valve repair system in the MiCLASP multicenter European postmarket clinical follow-up study (REGISTRATION: URL: https://www.clinicaltrials.gov; Unique identifier: NCT04430075).

Results

Analysis included 295 patients with functional mitral regurgitation (75.5±9.93 years old, 59.3% male) from the first 600 enrolled in the MiCLASP study, with AFMR in 17.6% (52) and VFMR in 82.4% (243). Patients with AFMR were older (79.7±6.67 versus 74.6±10.30 years), majority female (75.0% versus 33.3%), and had higher rates of hypertension (98.1% versus 82.3%) and atrial fibrillation (82.7% versus 60.1%) than patients with VFMR (all P<0.05). Patients with VFMR had higher NT-proBNP (N-terminal pro-B-type natriuretic peptide) levels (3350.0 [1720.0-6564.0] versus 1562.0 [790.0-2286.0]; P<0.001) and more severe mitral regurgitation (≥3+) at baseline (71.9% versus 46.2%; P<0.001). Procedural success was high (AFMR, 96.2%; VFMR, 97.1%; P=0.661), and patients with AFMR had shorter procedure duration (73.5 versus 85.5 minutes; P=0.044). One-year Kaplan-Meier estimate of freedom from all-cause mortality or heart failure hospitalizations was 79.3% in AFMR and 70.9% in VFMR (P=0.267). Both AFMR and VFMR groups demonstrated significant mitral regurgitation reduction (mitral regurgitation ≤1+, 93.1% and 81.3%), low mean transmitral gradients (3.5 and 3.1 mm Hg), significant proportional reductions in left ventricular end-diastolic volume (-12.9% and -16.4%) and left atrial volume (-9.6% and -10.9%), high proportions at New York Heart Association class I/II (76.5% and 64.6%), and significant increases in Kansas City Cardiomyopathy Questionnaire Overall Summary score (+18.0 and +11.6 points), respectively (all P<0.05 from baseline).

Conclusions

One-year MiCLASP results support the safety of mitral transcatheter edge-to-edge repair with the PASCAL system in both AFMR and VFMR, with comparable echocardiographic, functional, and quality-of-life changes, despite baseline differences in clinical presentation.