Does profound hypothermic circulatory arrest improve survival in patients with acute type a aortic dissection?

No evidence exists that profound hypothermic circulatory arrest (PHCA) improves survival or reduces the likelihood of distal aortic reoperation in patients with acute type A aortic dissection.

Records of 307 patients with acute type A aortic dissection from 1967 to 1999 were retrospectively reviewed. The influence of repair using PHCA (n=121) versus without PHCA (n=186) on death and freedom from distal aortic reoperation was analyzed using multivariable Cox regression models. Propensity score analysis identified a subset of 152 comparable patients in 3 quintiles (QIII-V) in which the effects of PHCA (n=113) versus no PHCA (n=39) were further compared.

For all patients, 30-day, 1-year, and 5-year survival estimates were 81+/-2%, 74+/-3%, and 63+/-3% (+/-1 SE). Survival rates and actual freedom from distal aortic reoperation was not significantly different between treatment methods in the entire patient cohort nor in the matched patients in quintiles III-V. Treatment method was not associated with differences in early major complications, late survival, or distal aortic reoperation rates in the entire patient sample or in quintiles III-V.

Aortic repair with or without circulatory arrest was associated with comparable early complications, survival, and distal aortic reoperation rates in patients with acute type A aortic dissection. Despite the lack of concrete evidence favoring the use of PHCA, it does no harm, and most of our group uses PHCA regularly because of its practical technical advantages and theoretical potential merit.