Extracorporeal Off-Pump Antegrade Cerebral Perfusion in Reconstructive Surgery for Type A Aortic Dissection with Cerebral Malperfusion

Introduction: Type A aortic dissection (TAAD) is a life-threatening condition that often leads to cerebral malperfusion (CM), a severe complication that can result in permanent neurological damage. Traditionally, a cardiopulmonary bypass (CPB) with selective antegrade cerebral perfusion (ACP) is employed during aortic arch reconstruction to protect cerebral circulation. However, the use of CPB carries inherent higher risks, including embolic events, hypothermia, and interrupted cerebral perfusion, especially in patients with CM. This study evaluates an innovative off-pump extra-corporeal ACP technique using an axillo-axillary shunt to provide uninterrupted bihemispheric cerebral perfusion during branch-first stage total aortic arch replacement (BF-TAR) for TAAD with CM; the shunt depends on cardiac contradiction to transfuse blood from the donor axillary artery to the recipient axillary artery, which then flows to through the carotid and vertebral arteries to the brain.

Methods: Between 2021 and 2023, 18 patients with TAAD complicated by CM underwent BF-TAR; the novel axillo-axillary shunt technique was employed for ACP because of the risks of ischemic neurologic injury. Outcomes measured included operative mortality, neurological complications, cardiopulmonary bypass times (measured after completion of the branch-first stage), and overall morbidity.

Results: The axillo-axillary shunt provided stable, continuous ACP in all patients. No new permanent neurological deficits were observed. Five (27.8%) patients experienced transient neurological symptoms such as blurred vision, dizziness, and confusion, which resolved within 48 hours. Operative mortality was 5.6% (1 patient), and minor complications included transitory lower limbs ischemia in 3 patients (16.7%) and deep sternal wound infection in 1 patient (5.6%). All transitory complications were managed by “watchful waiting”. The mean CPB time was 145.3 ± 48.6 minutes, while the mean cross-clamp time was 100.6 ± 17.4 minutes, which was better than the average of 227 ± 32 minutes and 147 ± 23 minutes reported in other studies. Postoperative imaging confirmed well-reconstructed aortic arches with no residual malperfusion or graft-related complications.

Conclusion: The off-pump axillo-axillary shunt technique provides a safe and effective method for maintaining continuous bihemispheric cerebral perfusion during total aortic arch replacement in patients with TAAD complicated by CM. This approach minimizes the risks associated with CPB, including embolic events and interrupted cerebral perfusion while achieving favorable neurological and surgical outcomes. Further studies with larger cohorts and longer follow-ups are warranted to validate the long-term benefits of this innovative technique.