Short and midterm results after left subclavian artery coverage during endovascular repair of the thoracic aorta

Background

To analyze the sequelae of the intentional left subclavian artery (LSA) coverage during thoracic endovascular aortic repair (TEVAR).

Methods

Retrospective analysis of prospectively collected data in a single center. Between March 1997 and October 2008, 88 of 220 patients (40%) had thoracic aortic lesions that required LSA coverage during TEVAR. Thirty-four of our patients (39%) were treated under urgent or emergent conditions for acute pathologies. The proximal landing zone was zone 0 in 10 patients (11%), zone 1 in 24 patients (27%), and zone 2 in 54 patients (61%). Debranching procedures of the supra-aortic vessels were performed in patients who were to undergo zone 0 or zone 1 deployment. Primary LSA revascularization was performed in 22 of the 88 patients (25%) at a median of 6 days before TEVAR. Median follow-up was 26.4 months (1-98 months).

Results

Technical success was achieved in 97%. Five primary (9%) and two secondary (4%) type Ia endoleaks in patients who underwent zone 2 deployment were observed and required further interventions. Fourteen (16%) primary type II endoleaks were observed; 10 of them fed by the LSA. Paraplegia rate was lower in patients with LSA coverage without revascularization than in other patients (1.5% vs 1.9%; odds ratio [OR], 0.774; 95% confidence interval [CI], 0.038-6.173; P = 1.000). Prior or concomitant infrarenal aortic replacement (P = .0019), renal insufficiency (glomerular filtration rate < 90 mL/min/1.73 m²) (P = .0024) and long segment aortic coverage (>200 mm) (P = .0157) were associated with significant higher risk of postoperative paraplegia. Stroke rate was lower in patients with LSA coverage without revascularization than in other patients (3% vs 3.9%; OR, 0.570; 95% CI, 0.118-2.761; P = .7269). Two patients (3%) developed left upper extremity symptoms and another two patients (3%) subclavian steal syndrome and required secondary LSA revascularization. The technical success rate for LSA revascularization was 94%.

Conclusion

By using a selective approach to the LSA revascularization, coverage of the LSA can be used to extend the proximal seal zone for TEVAR without increasing the risk of spinal cord ischemia or stroke. Indications for revascularization include long segment aortic coverage, prior or concomitant infrarenal aortic replacement, and renal insufficiency. In addition, a hypoplastic right vertebral artery, a patent left internal mammary artery graft, and a functioning dialysis fistula in the left arm would also be indications to perform revascularization.