Surgical results of hemiarch replacement for acute type A dissection

The appropriate surgical strategy for patients with an arch tear in acute type A dissection remains controversial. We retrospectively compared surgical results after hemiarch as compared with transverse aortic arch replacement in patients with an arch tear in acute type A dissection.

The records of 88 patients who consecutively underwent graft replacement for acute type A dissection between 1989 and 2001 were reviewed. The patients were divided into three groups: patients with ascending aortic replacement (group AS, n = 41), those with hemiarch replacement (group HA, n = 23), and those with transverse arch replacement (group AR, n = 24). Operative mortality and morbidity and late outcome were compared among the three groups.

The overall early (30 day) mortality was 11.3% (10/88), and in-hospital mortality was 14.7% (13/88). In-hospital mortality in groups AS, HA, and AR were 7.3%, 8.6%, and 33.3%, respectively (p = 0.011). Cardiopulmonary bypass, circulatory arrest, and operation times were significantly shorter in group HA than in group AR (p < 0.001). A smaller amount of intraoperative transfusion of red blood cells (p = 0.0006) and fresh-frozen plasma (p = 0.0003) was needed in group HA than in group AR, and postoperative bleeding during the first 24 hours postoperatively was significantly less in group HA than in group AR (p = 0.0028). The incidence of postoperative coma did not differ among the three groups (p = 0.89), nor did the incidence of postoperative patent false channel in the descending thoracic aorta (p = 0.57). Actuarial survival rates after 5 years were significantly better in group HA (91.3% +/- 5.9%) than in group AR (44.4% +/- 14.3%, p = 0.018). Freedom from reoperation on the distal aorta within 5 years did not differ among the groups (p = 0.46).

Hemiarch replacement for acute type A dissection demonstrated favorable early and late outcome. The extent of graft replacement influenced surgical mortality and morbidity. Whenever the intimal tear is located in the lesser curvature of the transverse arch, hemiarch replacement is recommended to improve overall operative mortality and morbidity.