# Circulatory arrest time above 30 min have significantly detrimental effects on the outcomes of type a aortic dissection repair

## TL;DR

This study finds that keeping blood circulation stopped for more than 30 minutes during aortic dissection surgery increases the risk of death and stroke.

## Contribution

The study identifies 30 minutes as a critical threshold for circulatory arrest time in type A aortic dissection repair.

## Key findings

- Circulatory arrest above 30 minutes is linked to higher 30-day and 12-month mortality rates.
- Longer arrest times also increase the risk of postoperative cerebrovascular accidents.
- Cerebral perfusion strategy during arrest does not affect stroke rates.

## Abstract

Acute aortic dissection of the ascending aorta is a life-threatening disease that poses a significant challenge for cardiovascular surgeons. Dissection of the aorta typically occurs when the aortic media separates from the intima. Surgical repair is performed emergently and classically involves the use of hypothermic circulatory arrest for distal aortic repair. The impact of circulatory arrest duration on postoperative outcomes is unclear with the critical time leading to increased risk being controversial. The purpose of this study is to elucidate the pivotal circulatory arrest time that increases surgical complications in patients undergoing type A aortic dissection repair.

This retrospective review of prospectively collected data included patients who underwent Aortic Dissection Repair from 2016 to 2022 at a New Jersey institution. Circulatory arrest time groups were stratified by above and below 30 min. Primary outcomes included 30-day mortality, postoperative length of stay (LOS), 30-day readmission and 12-month mortality. Secondary outcomes included postoperative complications of acute kidney injury (AKI), pericardial or pleural effusion, postoperative cerebrovascular accident (CVA) and postoperative atrial fibrillation. Outcomes were analyzed using Pearson’s Chi-squared, Fisher’s Exact, Regression Analysis and Pooled T-Tests, with significance set at p < 0.05.

A total of 109 patients were included, 87 of whom (80%) had arrest times below 30 min and 22 (20%) had arrest times above 30 min. There were no differences in preoperative baseline characteristics besides in patients with a history of congestive heart failure (p = 0.015). There were differences in cardiopulmonary bypass time (p < 0.001) and cross clamp time (p < 0.001). Patients with circulatory arrest times less than 30 min had a lower rate of 30-day mortality (p < 0.01), 12-month mortality (p < 0.019) and CVA (p = 0.003). There was no effect of cerebral perfusion strategy, retrograde vs. anterograde vs. lack thereof, during circulatory arrest on rate of CVA (p = 0.982).

Circulatory arrest time above 30 min increases the risk of postoperative mortality and CVA. Further investigation into evaluating these patients long-term should be pursued in addition to developing strategies to minimize circulatory arrest times to under 30 min.