Open and endovascular repair of type B aortic dissection in the Nationwide Inpatient Sample.

BACKGROUND: The use of stent grafts and mortality of stent graft repair of type B thoracic aortic dissection (T(B)AD) is not well defined. We sought to determine national estimates for the use and mortality of thoracic endovascular aortic repair (TEVAR) for T(B)AD in the United States.
METHODS: Records of the Nationwide Inpatient Sample (NIS) database between 2005 and 2007 were examined. International Classification of Diseases, 9th edition (ICD-9) diagnosis codes were used to select patients who underwent open or TEVAR with a stent graft for a diagnosis of thoracic aortic dissection or thoracoabdominal aortic dissection. We excluded patients with a diagnosis code for aortic aneurysm and those with procedure codes for cardioplegia or for operations on heart vessels or valves, which were considered type A dissections (T(A)AD). The remaining patients were considered as T(B)AD. We compared demographics and comorbidities, as well as adjusted complications and mortality rates, between patients undergoing TEVAR vs open repair.
RESULTS: We identified an estimated 10,466 repairs for dissection of the thoracic or thoracoabdominal aorta (open, 8659; TEVAR, 1818). Of these, 464 had a diagnosis of aortic aneurysm, and 5002 patients were considered T(A)AD. Of nonaneurysmal dissections, 5000 repairs were considered T(B)AD (open, 3619; TEVAR, 1381). The endovascular patients were older and had greater comorbidities, although only cardiac disease, renal failure, hypertension, and peripheral vascular disease were statistically significant. In-hospital mortality was 19% for open repair vs 10.6% for TEVAR (odds ratio [OR], 2.24; 95% confidence interval [CI], 1.36-3.67; P < .01). In-hospital mortality was significantly higher with open repairs coded as emergent admissions (20.1% vs 13.1%; P = .03), but did not reach statistical significance for elective admissions (12.3% vs 4.8%; P = .09). Cardiac complications (12.4% vs 4.9%, P < .01), respiratory complications (7.7% vs 4.3%, P = .02), genitourinary complications (9.0% vs 2.5%, P < .01), hemorrhage (14.0% vs 2.8%, P < .01), and acute renal failure (32.1% vs 17.2%, P < .01) were more frequent in the open repair group. Median length of stay was greater in the open repair group (10.7 vs 8.3 days, P < .01).
CONCLUSION: For patients with a diagnosis of T(B)AD who undergo repair, the endovascular approach is being used for older patients with greater comorbidities, yet has reduced morbidity and in-hospital mortality. The use of endovascular stent graft repair for type B thoracic aortic dissection merits further longitudinal analysis.