Three-Vessel Versus Unilateral Antegrade Cerebral Perfusion in Emergency Total Arch Replacement for Acute Type A Aortic Dissection

Overview

This single-centre retrospective observational cohort study describes the technical feasibility of direct three-vessel antegrade cerebral perfusion, designated modified antegrade cerebral perfusion (MACP), during emergency total arch replacement for acute type A aortic dissection. MACP delivers antegrade cerebral perfusion directly to the brachiocephalic, left common carotid, and left subclavian arteries. Outcomes are summarised descriptively and compared exploratorily with unilateral right axillary antegrade cerebral perfusion (uACP). Because perfusion strategy and treating surgeon were completely confounded, the comparative analyses are intended only to contextualise the technical experience and generate hypotheses.

Background and Rationale Acute type A aortic dissection requires emergency surgical repair. When total arch replacement is performed, cerebral protection during circulatory arrest is usually provided with hypothermia and antegrade cerebral perfusion. The optimal branch-level configuration of antegrade cerebral perfusion in emergency arch repair remains uncertain. This study evaluates a direct three-vessel antegrade cerebral perfusion strategy, designated modified antegrade cerebral perfusion (MACP). MACP was delivered using balloon-tipped catheters inserted into the brachiocephalic, left common carotid, and left subclavian arteries and connected to a three-line manifold from the cardiopulmonary bypass pump. The comparator was unilateral antegrade cerebral perfusion delivered through right axillary artery cannulation (uACP). Study Design and Population This is a single-centre retrospective observational cohort study conducted at China Medical University Hospital, Taichung, Taiwan. Consecutive adults aged 18 years or older who underwent emergency surgical repair for acute type A aortic dissection between 1 January 2021 and 30 April 2025 were identified from electronic health records and intraoperative perfusion records. The manuscript analytic cohort was restricted to patients undergoing emergency total arch replacement with either MACP or uACP. Objectives The primary objective is to describe the technical feasibility of MACP during emergency total arch replacement for acute type A aortic dissection. A secondary objective is to provide exploratory contextual outcome comparisons between MACP and uACP. The study is retrospective and observational; the comparative analyses are intended to generate hypotheses rather than to establish treatment effects. Outcome Measures The index outcome for the exploratory comparison is postoperative stroke during the index admission, defined as an abrupt focal neurological deficit due to cerebral infarction or intracranial haemorrhage confirmed on postoperative computed tomography or magnetic resonance imaging and adjudicated by a consultant neurologist. Secondary outcomes include in-hospital mortality, acute kidney injury, new dialysis, reoperation for bleeding, sepsis, postoperative atrial fibrillation, tracheostomy, mechanical ventilation duration, intensive care unit stay, and hospital stay. Statistical Analysis Continuous data are summarised as median and interquartile range, and binary data as n/N and percentage. Propensity scores for MACP were estimated using baseline covariates selected a priori and constrained by the small number of MACP patients. The primary exploratory comparison used 1:2 nearest-neighbour propensity score matching without replacement. Binary outcomes were analysed using Firth-penalised logistic regression, and continuous outcomes were compared using non-parametric methods with bootstrap confidence intervals. Sensitivity analyses examined alternative matching specifications, an unmatched propensity-score-adjusted model, and overlap-weighted covariate-balance diagnostics. All analyses are exploratory; p values are descriptive and no adjustment for multiplicity was performed. Ethics and Oversight The protocol was approved by the China Medical University Hospital Research Ethics Committee. All data were retrospectively collected and anonymised; informed consent was waived. No U.S. FDA-regulated drug, device, IND, or IDE is involved. Because this is a retrospective chart-review study, a formal data-monitoring committee was not required.