Development of a Risk Prediction Model and Clinical Risk Score for Isolated Tricuspid Valve Surgery

Background. Although tricuspid valve operations remain associated with high mortality (approximately 8% to 10%), no robust prediction models exist to support clinical decision making. We developed a preoperative clinical risk model with an easily calculable clinical risk score (CRS) to predict mortality and major morbidity after isolated tricuspid valve surgery. Methods. The Society of Thoracic Surgeons database records were evaluated for 2,050 isolated TV repair and replacement operations for any etiology performed at 50 hospitals (2002 to 2014) in a number of states. Parsimonious preoperative risk prediction models were developed using multiple-level mixed effects regression to estimate mortality and composite major morbidity risk. Model results were utilized to establish a novel CRS for patients undergoing tricuspid valve operations. Models were evaluated for discrimination and calibration. Results. Operative mortality and composite major morbidity rates were 9% and 42%, respectively. Final regression models performed well (both p < 0.001; areas under the receiver-operating characteristics curve 0.74 and 0.76) and included preoperative factors: age, sex, stroke, hemodialysis, ejection fraction, lung disease, New York Heart Association class, reoperation, and urgent or emergency status (all p < 0.05). A simple CRS from 0 to 10+ was highly associated (p < 0.001) with incremental increases in predicted mortality and major morbidity. Predicted mortality risk ranged from2% to 34% acrossCRS categories, and predicted major morbidity risk ranged from 13% to 71%. Conclusions. Mortality and major morbidity after isolated tricuspid valve surgery can be predicted using preoperative patient data from The Society of Thoracic Surgeons National Adult Cardiac Database. A simple clinical risk score predicts mortality and major morbidity after isolated tricuspid valve surgery. This score may facilitate perioperative counseling and identification of suitable patients for tricuspid valve surgery. (C) 2018 by The Society of Thoracic Surgeons