Preprocedural transthoracic echocardiography for predicting outcomes of transcatheter edge-to-edge repair for chronic primary mitral regurgitation.

Introduction And Objectives: Limited data exist on the prognostic usefulness of transthoracic echocardiography preceding MitraClip for chronic primary mitral regurgitation (MR). We evaluated the predictive ability of transthoracic echocardiography in this setting.

Methods: A total of 410 patients (median age, 83 years, 60.7% males) were included in the study. The primary outcome was the 1-year composite of all-cause mortality or heart failure hospitalization. Secondary endpoints encompassed individual elements of the primary outcome, the persistence of significant functional impairment or above-moderate MR at 1 year, and above-mild MR at 1-month.

Results: The only parameter associated with the risk of the primary outcome was a ventricular end systolic diameter index of ≥2.1 cm/m, corresponding to the cohort's 4th quartile (HR, 2.44; 95%CI, 1.09-4.68; P=.022). Concurrently, higher left atrial volume index (LAVi) and a mid-diastolic medial-lateral mitral annular diameter (MAD) equal to or above the cohort's median of 32.2mm were linked to a higher probability of death and heart failure hospitalization, respectively. LAVi of ≥ 60mL/m, above-mild mitral annular calcification, and above-moderate tricuspid regurgitation conferred higher odds of functional class III-IV or above-moderate MR persistence. All variables except LAVi and MAD, as well as indexed mid-diastolic medial-lateral MAD of ≥ 20.2mm/m and mitral effective regurgitant orifice area of ≥ 0.40 cm, were associated with greater-than-mild MR at 1 month.

Conclusions: Preprocedural increased indexed left heart dimensions, mainly left ventricular end-systolic diameter index, MAD, mitral annular calcification, mitral effective regurgitant orifice area, and tricuspid regurgitation mark a less favorable course post-MitraClip for chronic primary MR.