Acute and Delayed Mitral Annular Remodeling Following Transcatheter Edge‐to‐Edge Repair: An Echocardiographic Observational Study

BACKGROUND: Mitral transcatheter edge-to-edge repair (M-TEER) may modify mitral annular geometry beyond leaflet approximation, but the magnitude and temporal pattern of this effect remain incompletely characterized. AIMS: To assess acute and delayed changes in anteroposterior (AP) and intercommissural (IC) mitral annular diameters after M-TEER with MitraClip and to explore their association with clinical outcomes. METHODS: This retrospective single-center study included 151 patients undergoing M-TEER between February 2019 and June 2023. Annular diameters were measured by transoesophageal echocardiography before intervention and by transthoracic echocardiography before discharge and at the latest available echocardiographic follow-up. The primary analysis assessed continuous absolute changes in AP and IC diameters; an acute decrease of ≥ 1 mm in either diameter was retained only as an exploratory categorization. The exploratory clinical endpoint was the composite of all-cause death or heart-failure hospitalization. RESULTS: Median age was 78 (72-83) years, and 61% were male. From pre-intervention to discharge, AP and IC diameters decreased by 2.2 ± 3.8 and 2.3 ± 3.7 mm, respectively (both p < 0.001). Using the exploratory acute threshold, 129 patients (85.4%) had a ≥ 1 mm reduction; when categorized by the greatest reduction observed in either diameter, 16 (10.6%) had a 1 mm reduction, 16 (10.6%) a 2 mm reduction, 16 (10.6%) a 3 mm reduction, and 81 (53.6%) a > 3 mm reduction. Echocardiographic follow-up was available in 75 patients at a median of 4.7 months; the AP diameter remained stable, whereas the IC diameter showed a further reduction. During clinical follow-up, 22 patients reached the composite endpoint; acute annular reduction was not associated with a significant difference in event-free survival in exploratory analysis. CONCLUSIONS: M-TEER is associated with measurable acute changes in mitral annular dimensions, with additional delayed IC remodeling observed in a subset with follow-up imaging. Because baseline and post-procedural measurements were obtained with different echocardiographic modalities, the magnitude of the acute change should be interpreted cautiously. The prognostic relevance of annular remodeling remains hypothesis-generating.