Moderate Hypothermic Circulatory Arrest with Antegrade Cerebral Perfusion for Rapid Total Arch Replacement in Acute Type A Aortic Dissection.

Background: The optimal hypothermic level during circulatory arrest is controversial. The aim of our study was to comprehensively assess the impact of moderate hypothermic circulatory arrest with antegrade cerebral perfusion (ACP) on total aortic arch replacement.

Methods: From 2010 to 2013, data were collected from 99 consecutive patients with acute type A aortic dissection. All patients underwent total arch replacement plus frozen elephant trunk procedure. There were 51 patients in the deep hypothermia circulatory arrest (DHCA) group and 47 in the moderate hypothermia circulatory arrest (MHCA) group. Either unilateral or bilateral ACP was applied for cerebral protection. Perioperative data and measured outcomes were compared.

Results: Overall mean circulatory arrest time was 29.9 ± 6.0 minutes. Temporary neurologic dysfunction incidence was lower in the MHCA group compared with the DHCA group (21.3 vs. 40.4%, p = 0.041). The total 30-day mortality was 17.2% (14.9 vs. 19.2%, p = 0.568) and permanent neurologic dysfunction morbidity was 3.0% overall. In MHCA, less blood products were used than in DHCA. Moderate hypothermia was a protective factor for the composite outcome of temporary and permanent neurologic dysfunctions (odds ratio = 0.385; 95% confidence interval = 0.162-0.919). Hypothermic level did not significantly affect the perioperative alanine aminotransferase and serum creatinine levels.

Conclusion: Within a short circulatory arrest time, MHCA combined with ACP seemed to be a safe and effective method to protect cerebral and visceral organs during total aortic arch replacement.