Acute type A dissecting aortic aneurysm requiring emergency arch replacement

The intimal disruption is located or extends to the aortic arch in 10-20% of acute type A aortic dissections. Multiple tears are extremely rare. The reported mortality rate of emergency arch replacement varies from 25% to 40%, and therefore many surgeons elect to perform ascending aortic replacement only in these cases. However, with such an approach, the operative mortality rate of 10% is followed by a late mortality rate of up to 30% from residual aneurysm formation. Emergency arch replacement was carried out in five of 14 patients with an acute type A aortic dissection in whom the intimal tear either originated or extended into the arch, or in whom multiple tears existed. The ascending dissections were resected under moderate hypothermia, whereas the arch was explored under profound hypothermia, surface cooling and circulatory arrest. None of these five patients died; one developed slight hemiparesis, but no patient developed recurrent aneurysm in the follow-up period. These results appear to justify this aggressive approach, if it can be performed with an acceptable mortality rate < 25%, by avoiding the late deaths associated with more conservative surgical treatment.