Risk of late reoperations in patients with acute type A aortic dissection: impact of a more radical surgical approach.

OBJECTIVE To evaluate the incidence and risk factors for reoperations on the pre-isthmic aorta after repair of type A acute aortic dissection. METHODS From January 1979 to December 1996, 178 patients (125 males and 53 females with a mean age of 57 +/- 9 years) underwent emergency surgery for acute type A aortic dissection with an overall operative mortality rate of 21%. One hundred and forty-one patients (100 males and 41 females, aged 58 +/- 12 years), were discharged after successful replacement of the ascending aorta in 136 cases (96%) with extension to the transverse arch in 22 (16.2%) and associated total root or aortic valve replacement in 31 (22.8%) and 6 (4.4%) cases, respectively. Intimal tear resection and direct primary anastomosis of the aorta were performed in 5 patients (4%). Total follow-up was 690 patient-years, mean 5.1 +/- 4.1 years, with an actuarial survival rate at 5,10 and 15 years of 88%, 73% and 42%, respectively. RESULTS Nineteen patients (13%), 13 males and 6 females, aged 50 +/- 10 years, required a total of 22 reoperations with an actuarial freedom from reoperation at 5, 10 and 15 years of 94%, 64% and 35%, respectively. Initial repair consisted of replacement of the ascending aorta in 16 (84%) cases, with total root replacement in 2 (12%) and isolated aortic valve replacement in 1 (6%). Three patients (16%) were treated by intimal tear resection and direct primary anastomosis of the aorta. Mean interval between initial repair and reoperation was 5.2 +/- 3.1 years and indication to re-do surgery were severe aortic regurgitation in 2 (11%), aneurysmal evolution of the false lumen in 4 (21%) or both in 13 (68%). Extensive aortic reconstruction comprising simultaneous graft replacement of the aortic root, ascending aorta and aortic arch was necessary in 13 cases (68%), isolated replacement of the ascending aorta in 3 (16%), aortic valve in 2 (11%) and aortic arch in 1 (5%). There were 1 hospital (5%) and 2 late (11%) deaths at a mean follow-up of 2.5 +/- 2.4 years, with an actuarial survival at 5 years of 88%. Retrospective analysis of our total experience revealed that the introduction of the open distal anastomosis technique since 1990, reduced the incidence of reoperation from 11/46 (24%) to 8/95 (8.4%) (P < 0.05). However, also with this strategy 8/73 (11%) patients surviving replacement limited to the ascending aorta required reoperation versus none of the 22 patients surviving repair extended to the aortic arch. Three out of 5 (60%) patients undergoing intimal tear resection and primary anastomosis of the aorta early in our experience, required reoperation. CONCLUSIONS Management of patients with acute type A aortic dissection may include one or more surgical procedures after the initial emergency repair. Reoperations carry a low operative risk with good long-term survival and their incidence is reduced by routine open distal anastomosis and aggressive replacement of the aortic arch. Intimal tear resection and primary anastomosis of the aorta appear to be associated with increased risk of reoperation.