Midterm Outcomes of Open Descending Thoracic Aortic Repair in More Than 5,000 Medicare Patients

Background. Diseases involving the descending thoracic aorta (DTA) represent a heterogeneous substrate with a variety of therapeutic options. Although thoracic endovascular aortic repair has been increasingly applied to DTA disease, open surgical repair is ostensibly more durable. Methods. A total of 5,578 patients who underwent open DTA repair (Current Procedural Terminology code 33875) from 1999 to 2010 were identified from the Medicare database; 5,489 patients had complete data. Survival was assessed with Kaplan-Meier analysis. Cox regression determined predictors of death. Hospital and surgeon volume and variability were modeled, and their association with survival assessed. Results. Median survival after open DTA repair was only 4.3 years (95% confidence interval: 4.0 to 4.6). The likelihood of death varied significantly by certain aortic diseases: aortic rupture and acute aortic dissection patients had the highest early mortality. Survival beyond 180 days was best for patients with acute aortic dissection and isolated thoracic aortic aneurysm, and lowest for patients with thoracoabdominal aneurysm and aortic rupture. Hospital and surgeon volume, as well as inter-hospital and intersurgeon variability, had associations with overall survival. Conclusions. Open DTA repair has treated a spectrum of aortic diseases in Medicare beneficiaries. Overall mortality was high, predominately confined to the initial postoperative hazard phase. Independent hospital and surgeon effects, hospital and surgeon volume, and a more recent date of surgery correlated with improved survival, while increased operative urgency and complexity correlated with worse outcomes. These observations argue for regionalization of DTA treatment for Medicare patients in specialized centers to concentrate expertise, which should translate into better outcomes. (C) 2015 by The Society of Thoracic Surgeons