Understanding the Impact of Comorbidity-Interaction in Patients Undergoing Transcatheter Edge-to-Edge Mitral Valve Repair on Outcomes

BACKGROUNDTranscatheter Edge-to-Edge Mitral Valve Repair (M-TEER) is an accepted procedure for high-risk surgical patients with degenerative and functional mitral regurgitation. Non-cardiovascular comorbidities (NCCs) are highly prevalent in patients undergoing M-TEER. Although the impact of mitral valve anatomy and cardiac comorbidities in determination of M-TEER outcomes has been studied, precise understanding of the effect of the burden of NCCs on patients undergoing M-TEER remains unclear for acute outcomes. Our objective was to identify the association of NCC comorbidity-interaction patterns in patients undergoing M-TEER on length of stay (LOS), cost of care, and in-hospital major adverse cardiovascular events (MACE). METHODS9 245 admissions from the Nationwide Readmission Database that underwent M-TEER between 2015 and 2018 were included in the study. Patients were categorized by the overall burden of non-cardiovascular comorbidities (0, 1, 2, and [≥] 3). NCC included chronic liver disease, chronic lung disease, obesity, diabetes mellitus, dementia, major depressive disorder, chronic anemia, chronic kidney disease including end-stage renal disease (ESRD) on dialysis, and malignancy. Logistic Regression and Machine Learning (ML) algorithms were used to assess associations between comorbidity burden and in-hospital MACE. RESULTSOut of 9 245 index admissions, in-hospital MACE was recorded in a total of 504 (5.3 %). Of these, the majority (30.4%) had one NCC (n = 2 861). Patients with at least three NCCs had the longest median LOS [3.0, IQR (1.0 - 11.0)] and highest median cost of hospital care [$47 275, IQR (34 175.8 - 71 149.4)]. The Gradient Boosting (GB) classifier performed the best in predicting MACE with an AUROC of 96 % (95% CI: 0.95 - 0.97). The top features of importance that predicted in-hospital MACE were admission type, number of NCCs, and age in descending order. CONCLUSIONSCalibrated GB classifier identified patients with three NCCs as the subset of admission having the highest probability of a positive MACE outcome.