CT Angiography Features of Organ Malperfusion and Imaging Biomarker for Postoperative Adverse Complications in Acute Type A Aortic Dissection

Acute type A aortic dissection (ATAAD) is a high-risk disease complicated by organ malperfusion (OMP), which impairs surgical outcomes. This study explored computed tomography angiography (CTA) characteristics of OMP in ATAAD patients and identified imaging biomarkers for postoperative adverse complications (AC). A retrospective analysis included 432 ATAAD patients who underwent total arch replacement with frozen elephant trunk procedure (2016–2020), excluding those without preoperative aortic CTA. CTA assessed dissection features, branch vessel involvement, and tear severity. Analyses used Kaplan–Meier (KM) curves, Cox regression, logistic regression, and restricted cubic spline (RCS). Preoperative OMP was present in 155 (35.9%) patients. The Pre-OMP group had higher false lumen arc length (FLAL) ratios at multiple aortic levels, higher postoperative AC (38.7% vs. 24.5%, p=0.002) and 30-day mortality (17.4% vs. 6.5%, p<0.001) than the non-Pre-OMP group. KM analysis showed postoperative AC, rather than preoperative OMP, was the critical determinant of survival at follow-up (p<0.001 vs. p=0.069), but this effect does not persist in patients surviving beyond 1 year. Multivariable logistic regression identified ascending aorta level (AAL) FLAL ratio as an independent predictor of postoperative AC (OR: 1.335, 95%CI: 1.079–1.651, p=0.008); RCS confirmed nonlinearity, with AC risk rising significantly when AAL FLAL ratio >0.849. CTA of ATAAD patients with OMP mainly shows more severe central aortic tear characteristics. Postoperative AC is a critical determinant of survival at follow-up. The AAL FLAL ratio (>0.849) can serve as a reliable predictive biomarker for postoperative AC, aiding preoperative risk stratification and individualized surgical management in ATAAD.