Subclavian-to-Carotid Transposition for Coronary-Subclavian Steal Syndrome

Abstract

The recurrence of myocardial ischemia has been well described to occur when a proximal subclavian artery stenosis develops in patients who have had coronary revascularization based on an internal mammary artery. Carotid-to-subclavian bypass distal to the mammary artery has been the traditional vascular reconstruction for these patients. Other interventions in the literature have included aorta-subclavian bypass, axilloaxillary bypass, and subclavian angioplasty or stent placement. This case report describes the use of a subclavian-to-carotid transposition for the treatment of a patient with symptomatic coronary-subclavian steal syndrome. A 56-year-old man was admitted with unstable angina. Eleven years previously he had undergone coronary revascularization with a left internal mammary artery (LIMA) to the left anterior descending artery and a vein graft to the right coronary artery. Cardiac catheterization at this time revealed a 90% stenosis in the midbody of the vein graft and a 90% stenosis of the proximal left subclavian artery with a 40 mm Hg gradient. The LIMA graft had no intrinsic abnormality. Atherectomy of the vein graft stenosis was performed with a 30% residual stenosis. The patient then underwent a subclavian-tocarotid transposition with a temporary shunt. The shunt was placed from the proximal common carotid to the distal subclavian to allow retrograde perfusion of the LIMA during occlusion of the subclavian artery. Transposition was performed with carotid occlusion in standard fashion. Follow-up angiography and duplex ultrasound confirmed a widely patent transposition. The patient remains asymptomatic 5 years later. The use of a subclavian-to-carotid transposition for treatment of the coronary-subclavian steal syndrome successfully corrected this patient's cardiac symptoms. Advantages of transposition over other forms of subclavian revascularization include (1) an all-autogenous reconstruction, (2) a single anastomosis, (3) proven long-term durability, and (4) subcutaneous surgical exposure. The main disadvantage of this technique is the potential need for a temporary shunt during occlusion of the proximal subclavian artery. Patients with retrograde flow in the LIMA could have the procedure performed without a shunt. The widespread use of subclavian angioplasty does not appear to be justified in these patients owing to recurrent stenoses after angioplasty as compared to the excellent long-term patency rates for subclavian-to-carotid transpositions.