Comparison of Open Thoracoabdominal Repair for Chronic Aortic Dissections and Aneurysms.

OBJECTIVE: Aortic dissection is common in patients undergoing open surgical repair of thoracoabdominal aortic aneurysm (TAAA). Most often, dissection is chronic and is associated with progressive aortic dilatation. Because contemporary outcomes in chronic dissection are not clearly understood, we compared patient characteristics and outcomes after open TAAA repair between patients with chronic dissection and those with non-dissection aneurysm.

METHODS: We retrospectively analyzed data from 3470 open TAAA repairs performed in a single practice. Operations were for non-dissection aneurysm in 2351 (67.8%) and chronic dissection in 1119 (32.2%). Outcomes included operative mortality and adverse event, a composite variable comprising operative death and persistent (present at discharge) stroke, paraplegia, paraparesis, and renal failure necessitating dialysis. Logistic regression identified predictors of operative mortality and adverse events. Time-to-event analyses examined survival, death, repair failure, subsequent progressive repair, and survival free of failure or subsequent repair.

RESULTS: Compared with patients with non-dissection aneurysm, those with chronic dissection were younger, had fewer atherosclerotic risk factors, and were more likely to have heritable thoracic aortic disease and undergo extent II repair. The operative mortality rate was 8.5% (n=296) overall and was higher in non-dissection aneurysm patients (n=217; 9.2%) than in chronic dissection patients (n=79; 7.1%; P=.03). Adverse events were less frequent (P=.01) in patients with chronic dissection (n=145, 13.0%), 22 (2.0%) of whom had persistent paraplegia. Chronic dissection was not predictive of operative mortality (P=.5) or adverse events (P=.6). Operative mortality and adverse events, respectively, were independently predicted by emergency repair (OR=3.46 and 2.87), chronic kidney disease (OR=1.74 and 1.81), extent II TAAA repair (OR=1.44 and 1.73), increasing age (OR=1.04/yr and 1.04/yr), and increasing aortic cross-clamp time (OR=1.02/min and 1.02/min). Patients with chronic dissection had lower 10-year unadjusted mortality (42% vs 69%) but more frequent repair failure (5% vs 3%) and subsequent repair for progressive aortic disease (11% vs 5%) than patients with non-dissection aneurysm (P<.001); these differences were no longer statistically significant after adjustment.

CONCLUSIONS: Outcomes of open TAAA repair vary by aortic disease type. Emergency repairs and atherosclerotic diseases most commonly occur in patients with non-dissection aneurysm and independently predict operative mortality. Repair of chronic dissection is associated with low rates of adverse events, including operative mortality and persistent paraplegia, along with reasonable late survival and good durability. However, patients with chronic dissection tend to more commonly undergo subsequent repair to treat progressive aortic disease, which emphasizes the need for robust long-term imaging surveillance protocols.