Left subclavian artery occlusion by thoracic aortic stent graft: long-term clinical and duplex follow-up.

BACKGROUND In recent years there has been an increase in endovascular repair of thoracic aortic aneurysms. In cases of insufficient neck length, occlusion of left subclavian artery achieves proper sealing and is usually well tolerated. Selected cases require revascularization of the left subclavian artery, including patients after coronary bypass surgery (left internal mammary to left anterior descending) and those with arm claudication or subclavian steal syndrome. OBJECTIVES To evaluate the tolerability of left subclavian artery occlusion by stent graft without revascularization. METHODS Thirty patients with thoracic aortic aneurysms underwent endovascular repair between July 2000 and November 2004. Eleven of them had occlusion of the left subclavian artery that required revascularization in two. Follow-up (average 3 years) included: a) blood pressure measurements of both arms at rest, after effort and pulse palpation, and b) vertebral blood flow by duplex scan. RESULTS Of nine patients with no revascularization, 8 (89%) tolerated left subclavian artery occlusion with no claudication or steal syndrome; one (11%) suffered mild claudication only after effort and required no intervention. No left radial pulses were palpated in the nine patients. Blood pressure measurements in the left arm showed an average decrease of 40%, which remained constant after induced effort in all patients and was clinically insignificant. Duplex scan demonstrated reverse flow in the left vertebral artery in 8 of 9 patients (89%) and occlusion in 1 (originating in the arch and covered by the stent graft) with no clinical symptoms. CONCLUSIONS Left subclavian artery occlusion by stent graft is a tolerable procedure in the long term. In most cases, the constant decrease in blood pressure remained unchanged during follow-up and had no significant adverse affects. Most patients do not require revascularization prior to the endovascular procedure.