Correlation of intraprocedural and follow up parameters for mitral regurgitation grading after percutaneous edge-to-edge repair

Abstract

Abstract Background Percutaneous edge-to-edge mitral repair has merged as an effective therapy for moderate-to-severe mitral regurgitation (MR) in high surgical risk patients. Transesophageal echocardiogram (TEE) is crucial for procedure guiding and immediate result evaluation, whereas transthoracic echocardiogram (TTE) is largely used in follow up. However, there is no consensus on the best intraprocedural parameter to evaluate residual MR. Purpose To evaluate the predictive value of different MR parameters from intraprocedural TEE with grading in consecutive TTE during the follow up. Methods All the consecutive patients who underwent percutaneous mitral repair with the MitraClip system between 2010 and 2020 in our tertiary university hospital were considered for this study. Immediate posprocedural MR parameters (number of jets, summatory and maximum vena contracta (VC), summatory and maximum 3D effective regurgitation orifice (ERO) and pulmonary vein (PV) flow parameters) were reassessed when possible blindly to the follow up MR grading in sequential TTE. Results We included 88 patients (64.8% males) with a mean age of 76±10 years. Baseline MR was graded as moderate-to-severe in 13 (14.8%) and severe in 75 (85.2%). The most frequent MR etiology was secondary (44.3%) followed by primary (35.2%) and mixed (20.5%). Patients presented with mild left ventricular systolic dysfunction (LVEF 44.5±15.3%) and dilatation (LVEDVi 71.8 [51.5–102.8] mL/m2). MR grading distribution remained stable at 1 and 6 months follow up TTE. Among all the aforementioned criteria only summatory and maximum VC remained significant for different MR grade prediction. Thus, these values were able to identify MR ≥3 at 1 and 6 months (Table). Moreover, on ROC analysis maximum VC demonstrated an excellent discriminatory power to identify significant MR at 6 months (Figure). Thereby, a cut-off point of 0.45 cm was able to predict MR ≥3 with 88% sensitivity and 89% specificity. Conclusion Among intraprocedural TEE parameters to evaluate residual MR in percutaneous edge-to-edge mitral repair, maximum and summatory VC appeared to be the more reliable to predict significant insufficiency in the follow up. Funding Acknowledgement Type of funding sources: None. Table 1. Differences in intraprocedural TEE VC in relation with significant MR in follow-up TTEFigure 1. ROC curve of maximum VC for prediction of significant MR at 6 months