Background: Increasing evidence exists that an optimal residual mitral regurgitation (MR) result is crucial for the persistent improvement regarding not only symptoms but also clinical outcome of patients treated by an edge-to-edge device for severe MR. 

Objective: We aimed to identify predictors of an optimal postprocedural MR result (MR ≤1+) after edge-to-edge repair for severe MR and developed a basic echocardiographic scoring system to preprocedurally evaluate the probability of an optimal MR result after edge-to-edge repair.  

Methods: 365 consecutive patients treated with MitraClip for severe MR were evaluated by an independent echocardiography specialist for their post-procedural MR result and specific echocardiographic parameters. Subsequently, by stepwise univariate and multivariate regression analysis echocardiographic predictors of optimal MR result after MitraClip were identified and a solely echocardiographic scoring system was developed to preprocedurally calculate the probability of an optimal MR result after edge-to-edge repair. 

In a second step, the scoring system was validated in an external cohort of 50 independent patients, that were classified by a second independent echocardiography specialist.  

Results:

In 184 (50.4%) we found an optimal MR result, defined as no or trace residual MR (MR ≤1+) after edge-to-edge repair, in 181 (49.6%) we found acceptable result of residual MR ≥2+. 

We found 9 basic preprocedural echocardiographic parameters of the mitral valve associated with an acceptable, but not optimal MR result after MitraClip: functional etiology of MR, eccentricity of the MR jet, presence of several jets, central jet localization, commissure-to-commissure jet, PISA > 7 mm, prolapse, leaflet calcification and restriction of mitral leaflets.

By stepwise univariate and multivariate regression analysis we identified 5 basic echocardiographic items to impact on optimal MR result relevantly and developed the scoring system:

In the external cohort (n=50) for validation a cut-off-value of 14 points predicted an optimal MR result with a sensitivity of 85% and a specificity of 83%. By this approach, 42 patients (84%) were classified correctly before the MitraClip procedure either as optimal or acceptable. Only 4 patients were incorrectly classified as “optimal” but an acceptable result was achieved. 

Conclusion: Based on a cohort of 365 consecutive patients and an external validation cohort with 50 patients we were able to develop a 5-item-score based solely on preprocedural echocardiographic parameters to predict optimal residual MR results (MR ≤1+) after MitraClip intervention for severe MR.  With a cut-off-value of 14 points our score was able to predicte optimal MR results with a sensitivity of 85% and a specificity of 83%.