Comparison of Outcomes of Operative Therapy for Acute Type A Aortic Dissections Provided at High-Volume Versus Low-Volume Medical Centers in North Texas

Abstract

Immediate surgery is standard therapy for acute type A aortic dissections (TAAD). Because of its low incidence, many smaller cardiac surgery programs do not routinely perform this procedure because it may negatively affect outcomes. Many high-risk, low-volume (LV) surgical procedures are now preferentially performed in reference centers. We compared the outcomes of surgery for TAAD in high-volume (HV) and LV centers in a single metropolitan area to determine the optimal setting for treatment. Thirty-five of the 37 cardiac surgery programs in the Dallas Ft. Worth metropolitan area participate in a regional consortium to measure outcomes collected in the Society of Thoracic Surgeons Adult Cardiac Database. From January 01, 2008, to December 31, 2014, 29 programs had treated TAAD. Those programs performing at least 100 operations for TAAD were considered HV centers and the others LV. Surgery for TAAD was performed in 672 patients over the 7-year study period with HV centers performing 469 of 672 (70%) of the operations. Despite similar preoperative characteristics, operative mortality was significantly lower in HV versus LV centers (14.1% vs 24.1%; p = 0.001). There was no significant difference in postoperative paralysis rates (2.6% vs 4.5%; p = 0.196), stroke rates (10.7% vs 9.4%; p = 0.623), or 30-day readmission rates (12.1% vs 15.5%; p = 0.292). An improved survival rate in HV centers was maintained over a 5-year follow-up period. Surgery for TAAD in a single large metropolitan area was most commonly performed in HV centers. In conclusion, the treatment of acute thoracic aortic dissection is recommended to be performed in reference centers because of lower early and midterm mortality.