Acute and Delayed Mitral Annular Remodeling Following Transcatheter Edge-to-Edge Repair: An Echocardiographic...

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.

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.

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.

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.

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.