Intra-operative Coronary Subclavian Steal Syndrome

Abstract

Coronary-subclavian steal syndrome (CSSS) describes the condition whereby haemodynamically significant proximal subclavian artery stenosis results in flow limitation or reversal within the left internal mammary artery (LIMA) graft, classically precipitated by upper limb exertion. We report an unusual presentation, where a patient developed pronounced ST-depression and haemodynamic instability immediately following weaning from bypass. The patient was subsequently found to have occlusion of their left subclavian artery. Despite its incidence, there are currently no recommendations for screening for subclavian artery stenosis. We propose a preoperative screening algorithm that may allow for intervention prior to CABG, enabling risk-free use of the LIMA.