Abstract
Background: Chronic mitral regurgitation (MR) is categorized into primary and secondary MR (SMR). While primary MR arises from structural abnormalities of the mitral valve apparatus, SMR is a consequence of cardiac remodeling, typically due to heart failure or atrial fibrillation. Management strategies differ significantly, with primary MR requiring direct valvular intervention and SMR necessitating a comprehensive approach incorporating guideline-directed medical therapy (GDMT), revascularization, and resynchronization strategies. The MitraClip, a transcatheter edge-to-edge repair (TEER) device, has emerged as a recommended intervention for symptomatic severe SMR despite optimal GDMT. Objectives: This study aims to evaluate national trends in MitraClip placements in the U.S. from 2016 to 2021 and to assess 90-day readmission events following the procedure. Additionally, we analyze patient and socioeconomic factors associated with heart failure readmissions post-MitraClip placement to optimize patient selection criteria. Methods: The study utilized data from the National Inpatient Sample (NIS) for the years 2016-2021 and the National Readmissions Database (NRD) for 2021. Patients who underwent MitraClip placement were identified using ICD-10 code 02UG3JZ. We stratified the population based on demographics, hospital resource utilization, and comorbidities. Index admissions were classified based on the presence or absence of heart failure remissions within 90 days post-procedure. Statistical analyses, including ANOVA and logistic regression, were conducted to identify factors associated with readmissions. Results: MitraClip utilization demonstrated a rising trend from 2016 to 2021, with total annual procedures increasing from 869 to 2488. Mean patient age remained stable at 76-79 years, with a nearly equal sex distribution. In-hospital mortality remained low (1-3%) throughout the study period. A steady increase in hospital charges was observed, alongside a decline in the mean length of stay. Analysis of 4918 index admissions for MitraClip placement in 2021 identified 780 total readmissions within 90 days, with 206 (26.4%) attributed to heart failure. Factors significantly associated with increased risk of heart failure readmissions included atrial fibrillation (OR 3.77, CI 1.82-4.23), pulmonary hypertension (OR 3.96, CI 1.49-5.55), and chronic lung disease (OR 1.91, CI 1.32-2.77). Conclusions: The increasing adoption of MitraClip underscores its growing role in managing SMR. However, heart failure readmissions remain a significant concern. Identifying high-risk patient profiles can refine selection criteria and enhance post-procedural management strategies to improve clinical outcomes. Further research is needed to optimize patient selection and refine risk stratification for MitraClip interventions.