Patterns of visceral artery involvement and radiological malperfusion in aortic dissections.

Background: The aim of the present study was to analyze visceral arteries involvement in both acute type A (ATAAD) and type B (ATBAD) aortic dissection comparing the different types of radiological malperfusion.

Methods: Forty consecutive patients with ATAAD and 40 consecutive patients with ATBAD were included. Multiplanar reconstruction was used to analyze the luminal origin and the corresponding malperfusion of the coeliac trunk, the superior mesenteric artery, the left and the right renal arteries. Branch perfusion patterns were categorized into a simplified classification (true lumen, false lumen, dual lumen) and into a more detailed one: Class I, dissection involving but not extending into the branch; Class II, dissection extending into the branch and Class III, dissection causing ostial avulsion. The primary endpoints of the study were to assess patterns of visceral artery involvement and to evaluate mechanisms of radiological malperfusion in ATAAD and ATBAD.

Results: A total of 320 arterial branches were analyzed. Significant differences were found between ATAAD and ATBAD regarding the origin of the superior mesenteric artery (more Class I in ATBAD 87.5% vs. 67.5% in ATAAD, P=0.03) and left renal artery (more Class I in ATBAD 70% vs. 42.5% in ATAAD, P=0.04). Radiological malperfusion patterns were also different in ATAAD and ATBAD (more malperfusion from arteries originating from true lumen in ATBAD compared to ATAAD, P=0.05). There were no anatomical predictive factors for branch artery involvement.

Conclusions: Visceral branch artery involvement and mechanisms of radiological malperfusion were significantly different between ATAAD and ATBAD. These findings should be considered when guiding the optimal treatment strategy in acute aortic dissection.