Objective: Multiple-valve (MUV) procedures currently exhibit higher operative mortality than do single-valve procedures, but a paucity of scientific information exists to explain the observation. This topic was examined using The Society of Thoracic Surgeons Database.
Methods: All patients in the The Society of Thoracic Surgeons data set undergoing valve surgery (except pulmonary valve and aortic root operations) from 1993 through 2007 were identified (N = 623,039). Baseline characteristics and postoperative outcomes were contrasted between all seven combinations of single-valve and MUV procedures involving aortic, mitral, and tricuspid valves. Seven independent logistic regression analyses were performed, based on the seven procedures, and multivariable risk factors for mortality were compared, with emphasis on single-valve versus MUV procedures.
Results: Baseline characteristics for MUV procedures (n = 67,926) shared many similarities to those for single-valve procedures (n = 555,113), including age, ejection fraction, and comorbidities. Preoperative renal failure, New York Heart Association class III to IV, nonelective presentation, and reoperation were slightly more common in MUV subsets, and coronary bypass was less frequent. Operative mortality was almost double for MUV as compared with single-valve procedures (10.7% vs 5.7%, P = 0.0001). Categorical predictors with the largest odds ratios for mortality were emergency status, renal failure, and second reoperation. However, predictors for mortality were generally consistent in order and magnitude between the single-valve and MUV subgroups.
Conclusions: Despite similarities in preoperative profiles of the patients undergoing single-valve and MUV procedures, mortality for MUV surgery remains considerably higher. Determinants of operative mortality and morbidity differ little across the procedural groups, and these findings serve as a benchmark for future studies, as well as suggest a continued search for explanations of poorer MUV outcomes.