Morphologic Characteristics and Endovascular Management of Acute Type B Dissection Patients with Superior Mesenteric Artery Involvement.

Abstract Objective Despite being associated with static mesenteric malperfusion, the morphologic characteristics and optimal management of acute type B aortic dissection (ABAD) patients with superior mesenteric artery (SMA) involvement are poorly understood. We studied risk factors associated with such cases and reported outcomes of endovascular treatment. Methods From May 2016-May 2018, we examined 212 consecutive ABAD patients in our center. Those with SMA involvement (SMAI) were included and divided into a mesenteric malperfusion (MMP) group and a non-MMP group based on the clinical findings. Following thoracic endovascular aortic repair (TEVAR) with or without SMA revascularization, we compared clinical data, imaging results, and outcomes of management for those with MMP to those without. Results Computerized tomographic angiography confirmed 44 cases of SMAI: 12 (27.3%) were MMP and 32 (72.7%) were non-MMP. MMP patients presented more frequently with lower extremity malperfusion (33.3% vs. 3.1%, P=0.023) than non-MMP patients, with the odds ratio (OR) of 14.15 (P=0.047). Multivariate analysis showed that patients with a low value of true lumen (TL) to false lumen (FL) diameter ratio of SMA (TL/FL-SMA 1) [odds ratio (OR) 8.49, 95% confidence limit (CI): 1.24-58.26, P=0.029]. SMA TL thrombosis was a significant predictor of requiring an additional SMA revascularization after TEVAR among patients with MMP (P=0.045). During a mean 10-month follow up, complete false lumen thrombosis in the SMA was seen in eleven (25%) patients (33.3% vs. 21.9%, MMP vs. non-MMP, P=0.43). The overall mortality rate was 6.82% (16.7% in the MMP group and 3.1% in the non-MMP group, P=0.09). Conclusions Limb ischemia and TL/FL-SMA ratios are two independent predictors for developing MMP in ABAD with SMAI. TEVAR can be safely approached in these patients, while SMA TL thrombosis predicts the need for SMA revascularization.