Usefulness of computed tomography to predict residual mitral regurgitation after transcatheter mitral valve edge-to-edge repair

Background: Multidetector computed tomography (MDCT) can provide valuable information for preprocedural planning of transcatheter mitral valve interventions. However, no data exist on MDCT parameters predicting residual mitral regurgitation (MR) post-MitraClip (Abbott Laboratories, Abbott Park, IL, USA).

Methods: We analyzed preprocedural MDCTs of 78 consecutive patients with secondary MR undergoing MitraClip implantation at our institution. Moderate-or-severe mitral leaflet calcification (MLC) was defined as calcification, with-or-without mitral annular calcification, extending beyond the mitral leaflet base. Residual MR was assessed by postprocedural transesophageal echocardiography, and clinical outcomes were assessed at 1-year.

Results: Fifteen patients (19 %) had residual MR ≥2+. Compared to patients with none-or-mild residual MR, MDCT-derived mitral valve orifice area (MVOA) to mitral annulus area (MAA) ratio was significantly lower (0.32 ± 0.06 vs. 0.39 ± 0.09; p = 0.003), and the prevalence of MLC was higher (40 % vs. 18 %; p = 0.057) in those with residual MR ≥2+. Furthermore, the MVOA/MAA ratio and MLC were independent predictors of residual MR ≥2+ post-MitraClip [adjusted odds ratio (OR_adj): 0.88 (0.80-0.97) and 5.50 (1.16-26.23), respectively]. On receiver-operating-characteristic-curve analysis, MVOA/MAA ratio <0.31 had a sensitivity of 87 % and a specificity of 60 % for residual MR ≥2+. When patients were classified according to the presence of MLC and an MVOA/MAA ratio <0.31, those with both parameters had significantly higher rates of postprocedural residual MR ≥2+ and mitral reintervention at 1-year than those with only one, and those without both parameters.

Conclusions: In patients with secondary MR undergoing the MitraClip procedure, preprocedural MDCT parameters, specifically MVOA/MAA ratio and MLC, are useful to predict postprocedural residual MR.