Renal artery involvement as a predictor of severe malperfusion in acute type A aortic dissection: a retrospective cohort study.

BACKGROUND: Reliable radiographic indicators to assess the severity and prognosis of acute type A aortic dissection (ATAAD) are lacking. This study investigates whether renal artery involvement (RAI) on preoperative imaging serves as a marker of extensive branch vessel compromise and malperfusion. METHODS: This retrospective study analyzed 471 consecutive patients who underwent open surgical repair for ATAAD between January 2020 and June 2022. RAI was defined on computed tomography angiography (CTA) as dissection membrane extension to the renal artery ostium. Patients were divided into RAI (n=289) and non-RAI (n=182) groups. Propensity score matching (PSM) minimized baseline differences. Multivariable ordered logistic regression assessed the association between RAI and the number of malperfused organ systems. Cox regression identified risk factors for mortality. RESULTS: The RAI group exhibited more extensive aortic branch involvement (P<0.05), required more concomitant branch procedures, and had a higher incidence of end-organ malperfusion (P=0.006) and serious adverse events (SAEs) (P=0.009), consistent after PSM. Ordered logistic regression showed that RAI was associated with malperfusion [odds ratio (OR) =2.00, 95% confidence interval (CI): 1.25-3.27, P=0.005]. Cox regression identified RAI as an independent risk factor for overall mortality [hazard ratio (HR) =3.48, 95% CI: 1.15-10.47, P=0.03] and mid-term mortality (HR =3.42, 95% CI: 1.14-10.31, P=0.03). Long-term follow-up recorded 11 deaths among hospital survivors; no significant association was observed between RAI and permanent dialysis dependence (log-rank P=0.18). CONCLUSIONS: RAI on preoperative CTA is a simple, objective indicator of extensive aortic branch compromise and higher malperfusion burden in ATAAD, identifying a high-risk cohort with worse perioperative outcomes and reduced mid-term survival.