Development and Validation of a Machine Learning Risk-Prediction Model for 30-Day Readmission for Heart Failure Following Transcatheter Aortic Valve Replacement (TAVR-HF Score)

Transcatheter aortic valve replacement (TAVR) is the treatment of choice for patients with severe aortic stenosis across the spectrum of surgical risk. About one-third of 30-day readmissions following TAVR are related to heart failure (HF). Hence, we aim to develop an easy-to-use clinical predictive model to identify patients at risk for HF readmission. We used data from the National Readmission Database (2015-2018) utilizing ICD-10 codes to identify TAVR procedures. Readmission was defined as the first unplanned HF readmission within 30-day of discharge. A machine learning framework was used to develop a 30-day TAVR-HF readmission score. The receiver operator characteristic curve was used to evaluate the predictive power of the model. A total of 92,363 cases of TAVR were included in the analysis. Of the included patients, 3299 (3.6%) were readmitted within 30 days of discharge with HF. Individuals who got readmitted, vs those without readmission, had more emergent admissions during index procedure (33.4% vs 19.8%), electrolyte abnormalities (38% vs 16.7%), chronic kidney disease (34.8% vs 21.2%), and atrial fibrillation (60.1% vs 40.7%). Candidate variables were ranked by importance using a parsimony plot. A total of 7 variables were selected based on predictive ability as well as clinical relevance: HF with reduced ejection fraction (25 points), HF preserved EF (20 points), electrolyte abnormalities (17 points), atrial fibrillation (12 points), Charlson comorbidity index (<6 = 0, 6-8 = 9, 9-10 = 13, >10 = 14 points), chronic kidney disease (7 points), and emergent index admission (5 points). On performance evaluation using the testing dataset, an area under the curve of 0.761 (95% CI 0.744-0.778) was achieved. Thirty-day TAVR-HF readmission score is an easy-to-use risk prediction tool. The score can be incorporated into electronic health record systems to identify at-risk individuals for readmissions with HF following TAVR. However, further external validation studies are needed.