ST-Segment elevation acute myocardial infarction due to severe hypotension and proximal left subclavian artery stenosis in a prior coronary artery bypass graft patient

Coronary steal: how many thieves are out there?

The colorful term "coronary steal" arose in 1967 to parallel "subclavian steal" coined in an anonymous 1961 editorial. In both instances, the word "steal" described flow reversal in the setting of an interconnected but abnormal vascular network-in one case a left subclavian stenosis proximal to the origin of the vertebral artery and in the other case a coronary fistula. Over time, the term has morphed to include a larger set of pathophysiology without explicit flow reversal but rather with a decrease in stress flow due to other mechanisms. This review aims to shed light on this phenomenon from a clinical and a pathophysiological perspective, detailing the anatomical and physiological conditions that allow so-called steal to appear and offering treatment options for six distinct scenarios.

A Unique Case of STEMI STEALing the Flow

We report a case of a 55-year-old woman with previous coronary artery bypass grafting. She presented with acute ST-segment elevation myocardial infarction secondary to occlusion of the proximal left subclavian artery causing reduced flow in the left internal mammary artery to left anterior descending artery graft. (Level of Difficulty: Intermediate.)

Review of coronary subclavian steal syndrome

The clinical benefits of using the left internal mammary artery (LIMA) to bypass the left anterior descending artery are well established making it the most frequently used conduit for coronary artery bypass surgery (CABG). Coronary subclavian steal syndrome (CSSS) occurs during left arm exertion when (1) the LIMA is used during bypass surgery and (2) there is a high grade (≥75%) left subclavian artery stenosis or occlusion proximal to the ostia of the LIMA resulting in "stealing" of the myocardial blood supply via retrograde flow up the LIMA graft to maintain left upper extremity perfusion. Although CSSS was once thought to be a rare phenomenon, its prevalence has been underestimated and is becoming increasingly recognized as a serious threat to the success of CABG. Current guidelines are lacking on recommendations for screening of subclavian artery stenosis (SAS) pre- and post-CABG. We hope to provide an algorithm for SAS screening to prevent CSSS in internal mammary artery bypass recipients and review treatment options in the percutaneous era.

Coronary subclavian steal syndrome

PURPOSE OF REVIEW

Coronary subclavian steal syndrome (CSSS) is the reversal of blood flow in an internal mammary artery bypass graft that results in coronary ischemia. CSSS is an uncommon but treatable cause of coronary ischemia. In this review, we highlight the historical background and epidemiology of CSSS, common clinical presentations, diagnosis of CSSS and management strategies for relieving ischemia. We also present a case report to illustrate the complexity of CSSS and percutaneous management using current technology.

RECENT FINDINGS

Most commonly, CSSS results from atherosclerotic stenosis of the subclavian artery and occurs in 2.5-4.5% of patients referred for coronary artery bypass grafting (CABG). All patients referred for CABG should have bilateral noninvasive brachial blood pressures checked to screen for the underlying subclavian stenosis. A review of 98 case reports with 128 patients demonstrated a diverse clinical presentation of CSSS, including acute myocardial infarction, unstable angina and acute systolic heart failure. Resolution of CSSS symptoms has been reported with both surgical and percutaneous revascularization. Long-term patency with either revascularization strategy is excellent. Percutaneous revascularization is largely considered the first-line therapy for CSSS and can be safely performed prior to CABG to prevent CSSS.

SUMMARY

CSSS should be suspected in patients presenting with angina, heart failure or myocardial infarction after CABG. Successful amelioration of CSSS symptoms can be safely and effectively performed via percutaneous revascularization.

Unusual suspect-coronary subclavian steal syndrome caused severe myocardial ischemia

Coronary-subclavian steal syndrome represents a reversal of blood flow in left internal mammary artery. The most common cause of the syndrome is atherosclerotic disease in the ipsilateral, proximal subclavian artery. We present a case of 72 years old male, who developed severe anginal and neurological complaints three years after coronary artery bypass graft surgery(CABG).

Effective emergent endovascular recanalization for acute coronary syndrome with left subclavian artery occlusion in a prior coronary artery bypass graft patient

A 78-year-old female was hospitalized because of multiple bone fracture caused by falling down. She undertook coronary artery bypass graft (CABG) using left internal mammary artery (LIMA) about 10 years ago. She complained chest pain on the day of admission with hypotension. Emergent angiogram revealed total occlusion of left subclavian artery (SCA). We re-canalized left SCA with stent. Hemodynamics and symptom dramatically improved after the procedure. Acute coronary syndrome due to SCA occlusion after CABG using LIMA was rare, but we have to consider the possibility. Endovascular therapy to SCA lesion might be a proper strategy for these cases.

Subclavian steal syndrome presenting as recurrent pulmonary oedema associated with acute left ventricular diastolic dysfunction

Subclavian steal syndrome typically presents as angina in patients with internal mammary artery grafts. Atypical clinical presentations have been rarely described. We report an unusual case of subclavian steal syndrome presenting as pulmonary oedema with acute left ventricular diastolic dysfunction and preserved ejection fraction in a patient with internal mammary artery graft and severe stenosis of the proximal left subclavian artery. After successful angioplasty and stenting of subclavian artery, the patient remained asymptomatic for six months, but then experienced acute diastolic dysfunction and recurrent pulmonary oedema associated with critical subclavian in-stent restenosis with stent deformation. This report points out that, in patients with internal mammary-to-LAD grafts, subclavian steal syndrome may present as acute left ventricular diastolic dysfunction and pulmonary oedema even in the presence of normal ejection fraction.

Coronary subclavian steal syndrome causing acute myocardial infarction in a patient undergoing coronary-artery bypass grafting

Coronary subclavian steal syndrome with retrograde blood flow in the left internal mammary-coronary bypass graft is a rare but severe complication of cardiac surgery. The authors present a case of a 68-year-old man after coronary-artery bypass grafting using an internal mammary artery. He had been suffering from angina pectoris for the last several years before surgery. The patient was resuscitated at home by emergency medical service because of primary ventricular fibrillation due to an acute myocardial infarction 5 years after surgery. An occlusion of the left subclavian artery with the retrograde blood flow in the left internal mammary coronary bypass was found. This could have been the cause of insufficiency in coronary blood flow and ischemia of the myocardial muscle. The subclavian artery occlusion was successfully treated with percutaneous transluminal angioplasty and implantation of 2 stents. The patient remained free of any symptoms 2 years after this procedure.