Modified hypothermic circulatory arrest for emergent repair of acute aortic dissection type a: a single-center experience

BACKGROUND: Deep hypothermic circulatory arrest (DHCA) with antegrade cerebral perfusion has been historically preferred for organ protection during surgical repair of the acute aortic dissection type A. However, in the past decades, different perfusion-specific strategies with a growing trend to increase the body temperature at circulatory arrest emerged. In this study, we retrospectively analyzed the clinical results of our modified protocol for cardiopulmonary bypass and hypothermia management. METHODS: Between February 2007 and September 2012, 54 consecutive patients suffering from acute aortic dissection type A underwent emergent surgery. All patients received hypothermic circulatory arrest in combination with antegrade cerebral perfusion. The patients were divided into two subsets according to the degree of hypothermia and perfusion strategies: namely the DHCA group and the group of modified hypothermic circulatory arrest (MHCA). RESULTS: The overall 30-day mortality was 27.8% and was not significantly different between groups (DHCA, 33.3%, MHCA, 19%; p=0.253). The requirement for blood product transfusion in MHCA patients was significantly less as as compared with the patients in the DHCA group. No difference occurred in the incidence of temporary neurologic dysfunction, dialysis-dependent renal failure, or reexploration for bleeding between two groups of patients. The use of MHCA was identified as a protective factor against the postoperative composite complications (OR, 0.78; CI, 0.52 to 0.98; p=0.04) and the prolonged intensive care unit stay (OR, 0.8; 95% CI, 0.56 to 0.98; p=0.04). CONCLUSIONS: Moderate hypothermia in combination with selective brain perfusion and systemic retrograde perfusion is associated with adequate cerebral and visceral protection, reduced postoperative complications and shortened intensive care unit stay in our series. This modified perfusion strategy may help in improving perioperative outcomes in this particular group of patients.