Endovascular treatment of coronary subclavian steal syndrome: a case series highlighting the diagnostic usefulness of a multimodality imaging approach.

Background: Coronary subclavian steal syndrome (CSSS) is an uncommon complication observed in patients after coronary artery bypass surgery with left internal mammary artery (LIMA) grafts. It is defined as coronary ischaemia due to reversal flow from the LIMA to the left subclavian artery (SA) when a proximal left SA stenosis is present. In practice, the entire clinical spectrum of ischaemic heart disease, ranging from asymptomatic patients to acute myocardial infarction, may be encountered.

Case summary: Three cases of CSSS recently detected at our hospital are being described. Two patients presented with an acute coronary syndrome, so diagnosis was suspected based on coronary angiography findings, as retrograde blood flow from LIMA to the distal SA was present. Myocardial ischaemia was documented by myocardial perfusion scintigraphy in one case. The third patient was asymptomatic and CSSS was suspected during physical examination and confirmed by computed tomography (CT). Endovascular intervention with balloon-expandable stent implantation of the stenotic SA was performed by vascular surgeons in all patients. No periprocedural complications occurred, and complete resolution of symptoms was achieved.

Discussion: In CSSS, subclavian angiography is the standard diagnostic test. However, other diagnostic techniques may be valuable to better clarify this challenging diagnosis. In the herein small series, the usefulness of a multimodality imaging approach including Doppler ultrasound, myocardial perfusion scintigraphy, and CT is well demonstrated. Furthermore, this study endorses the safety and utility of endovascular treatment in different clinical scenarios, including asymptomatic patients.