Results
A total of 533 patients were included in this study. Baseline characteristics and preoperative comorbidities are presented inTable 1 . The majority of patients in this cohort were male (333 [63.4%]) and of white race (487 [91.4%]). A total of 310 (58.2%) cases were performed as an urgent procedure, and 62 (11.6%) were categorized as emergent or salvage procedures. Median Society of Thoracic Surgeons predicted risk of mortality was 3.8% (IQR 1.9% to 7.9%).
The most common procedure performed was isolated coronary arterial bypass grafting (CABG), performed in 159 (29.8%) cases. Other commonly performed procedures were double valve interventions (84 [15.8%]) and combined CABG and aortic valve replacement (60 [11.3%]). Operative characteristics are displayed in Table 2 . Cardiopulmonary bypass was utilized in 91.6% of cases with a median perfusion time and cross clamp time of 185 minutes (IQR 123 to 260) and 122 minutes (IQR 81 to 179), respectively.
Intraoperatively, or within the postoperative period, a total of 442 (82.9%) of patients had an IABP placed (Table 3 ). A total of 23 (4.3%) had an Impella device placed, and 115 (21.6%) were placed on extracorporeal membrane oxygenation support. Three (0.6%) patients had an unplanned ventricular assist device placed. Most (487 [91.37%]) patients were supported with one circulatory support device, while 4 (0.75%) patients were exposed to three different forms of MCS during the intraoperative and postoperative period.
Postoperative outcomes are presented in Table 4 . In this cohort, operative mortality was 29.8%. Blood products were administered in 80.9% of patients, and the rate of reoperation was 46.5%. Other complications included prolonged mechanical ventilation (334 [62.7%]), renal failure (170 [31.9%]), pneumonia (116 [21.8%]), and stroke (31 [17.1%]). Patients spent a median time of 124 hours in an intensive care unit setting.