Outcomes of patients with acute type A aortic dissection and concomitant lower extremity malperfusion

Abstract

Objective: The occurrence of acute lower limb ischemia (ALLI) is a serious risk within the context of aortic dissection repair. The aim of the present study was to examine the outcomes of patients with acute type A aortic dissection (ATAD) and concomitant lower extremity malperfusion.

Methods: We performed a retrospective medical record review at our tertiary referral center of patients who underwent ATAD repair from January 2002 to June 2018. We used univariate and multivariate analyses to compare the outcomes of patients with and without lower extremity malperfusion. The primary outcomes were 30-day and 1-year mortality.

Results: A total of 378 patients underwent ATAD repair during the study period. Their mean age was 57 years, 68% were men, and 51% were White. A total of 62 patients (16%) presented with concomitant ALLI, including 35 (9%) who presented with isolated ALLI and 27 (7%) who presented with ALLI and concomitant malperfusion of at least one other organ. Of the 62 patients with ALLI, 46 underwent only proximal aortic repair. Of the 378 patients, 6 died within the first 24 hours, and their limb perfusion was not assessed. Among the 40 patients who underwent isolated proximal repair and survived >24 hours, 34 (85%) had resolution of their ALLI. Of the 16 patients who underwent concomitant lower extremity peripheral vascular procedures, 10 had bypass procedures and 1 died within 24 hours due to refractory coagulopathy and hypotension. All six patients with adequate follow-up imaging studies had asymptomatic occlusion of the bypass graft with recanalization of the occluded native arteries. Patients who presented with any organ malperfusion had increased 30-day (odds ratio, 1.8; P = .04) and 1-year (odds ratio, 1.8; P = .04) mortality and decreased overall survival (P < .01). For the patients with isolated ALLI, no significant differences were found in 30-day or 1-year mortality or overall survival (P = .57).

Conclusions: Proximal repair of ATAD resolves most cases of associated ALLI, and isolated ALLI does not affect short- or long-term survival. All patients with follow-up in our study who underwent extra-anatomic bypass developed asymptomatic graft occlusion, which could be attributed to competitive flow from the remodeled native arterial system. We believe that rapid and aggressive restoration of flow to the lower extremity is the best method to treat ALLI malperfusion syndrome. Close monitoring for the development of compartment syndrome is recommended.

Keywords: ATAD; Acute limb ischemia; Acute type A aortic dissection; Malperfusion syndromes.