Left subclavian artery revascularization in zone 2 thoracic endovascular aortic repair is associated with lower stroke risk across all aortic diseases

Background

The best management strategy for the left subclavian artery (LSA) in pathologic processes of the aorta requiring zone 2 thoracic endovascular aortic repair (TEVAR) remains controversial. We compared LSA coverage with or without revascularization as well as the different means of LSA revascularization.

Methods

A retrospective chart review was conducted of patients with any aortic diseases who underwent zone 2 TEVAR deployment from 2007 to 2014. Primary end points included 30-day stroke and 30-day spinal cord injury (SCI). Secondary end points were 30-day procedure-related reintervention, freedom from aorta-related reintervention, aorta-related mortality, and all-cause mortality.

Results

We identified 96 patients with zone 2 TEVAR who met our inclusion criteria. The mean age of the patients was 62 years, with 61.5% male. Diseases included acute aortic dissections (n = 25), chronic aortic dissection with aneurysmal degeneration (n = 22), primary aortic aneurysms (n = 21), penetrating aortic ulcers/intramural hematomas (n = 17), and traumatic aortic injuries (n = 11). Strategies for the LSA included coverage with revascularization (n = 54) or without revascularization (n = 42). Methods of LSA revascularization included laser fenestration with stenting (n = 33) and surgical revascularization: transposition (n = 10) or bypass (n = 11). Of the 54 patients with LSA revascularization, 44 (81.5%) underwent LSA intervention at the time of TEVAR and 10 (18.5%) at a mean time of 33 days before TEVAR (range, 4-63 days). For the entire cohort, the overall incidence of 30-day stroke was 7.3%; of 30-day SCI, 2.1%; and of procedure-related reintervention, 5.2%. At a mean follow-up of 24 months (range, 1-79 months), aorta-related reintervention was 15.6%, aorta-related mortality was 12.5%, and all-cause mortality was 29.2%. The 30-day stroke rate was highest for LSA coverage without revascularization (6/42 [14.3%]) compared with any form of LSA revascularization (1/54 [1.9%]; P = .020), with no difference between LSA interventions done synchronously with TEVAR (1/44 [2.3%]) vs metachronously with TEVAR (0/10 [0%]; P = .63). There was no significant difference in 30-day SCI in LSA coverage without revascularization (2/42 [4.8%]) vs with revascularization (0/54 [0%]; P = .11). There was no difference in aorta-related reintervention, aorta-related mortality, or all-cause mortality in coverage without revascularization (5/42 [11.9%], 6/42 [14.3%], and 14/42 [33.3%]) vs with revascularization (10/54 [18.5%; P = .376], 6/54 [11.1%; P = .641], and 14/54 [25.9%; P = .43], respectively). After univariate and multivariable analysis, we identified LSA coverage without revascularization as associated with a higher rate of 30-day stroke (hazard ratio, 17.2; 95% confidence interval, 1.3-220.4; P = .029).

Conclusions

Our study suggests that coverage of the LSA without revascularization increases the risk of stroke and possibly SCI.