Prognostic Value of Left Ventricular Global Longitudinal Strain in Transcatheter Edge-to-Edge Repair for Chronic Primary Mitral Regurgitation

Eur Heart J Cardiovasc Imaging. 2024 Mar 26:jeae083. doi: 10.1093/ehjci/jeae083. Online ahead of print.

Abstract

Aims: Left ventricular global longitudinal strain (LVGLS) is a known outcome predictor in transcatheter edge-to-edge repair (TEER) for functional mitral regurgitation (MR). We aimed to assess its prognostic yield in the setting of TEER for chronic primary MR.

Methods and results: We conducted a single-center, retrospective analysis of 323 consecutive patients undergoing isolated, first-time procedures. Stratified by baseline LVGLS quartiles (≤-19%, -18.9-(-16)%, -15.9-(-12)%, > -12%), the cohort was evaluated for the primary composite outcome of all-cause mortality or heart failure hospitalizations, as well as secondary endpoints consisting of mitral reinterventions and the persistence of significant residual MR and/or functional disability - all along the first year after intervention. Subjects with worse (i.e., less negative) LVGLS exhibited higher comorbidity, more advanced HF, and elevated procedural risk. Post-TEER, those belonging to the worst LVGLS quartile group sustained increased mortality (16.9 vs 6.3%, Log-Rank p = 0.005, HR 1.75, 95% CI 1.08-4.74, p = 0.041) and, when affected by LV dysfunction/dilatation, more primary outcome events (21.1 vs 11.5%, Log-Rank p = 0.037, HR 1.68, 95% CI 1.02-5.46, p = 0.047). No association was demonstrated with other endpoints. Upon exploratory analysis, 1-month postprocedural LVGLS directly correlated with and was worse than its baseline counterpart by 1.6%, and a more impaired 1-month value - but not the presence/extent of deterioration - conferred heightened risk for the primary outcome.

Conclusion: TEER for chronic primary MR is feasible, safe, and efficacious irrespective of baseline LVGLS. Yet, worse baseline LVGLS forecasts a less favorable postprocedural course, presumably reflecting a higher-risk patient profile.

Keywords: Global longitudinal strain; MitraClip; Mitral regurgitation; Mitral transcatheter edge-to-edge repair; Transcatheter mitral valve repair.