Coronary subclavian steal syndrome: non-invasive imaging and percutaneous repair

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.

Aortic arch vessel disease and rationale for echocardiographic screening

Atherosclerosis of the proximal branches of the aortic arch has compelling clinical implications that warrant the application of direct noninvasive detection of the disease. The prevalence of aortic arch vessel disease in an aging and at-risk community and clinical population has been underreported and undertreated despite an associated increase of all-cause and cardiovascular mortality. Intrathoracic duplex imaging has been validated as an accurate noninvasive tool to detect, characterize, and follow native aortic arch vessel disease and its sequelae and correction. Such duplex techniques are easily integrated into routine echocardiography with focused training and minimal time investment in the examination. A paucity of available resources exists across disciplines regarding ultrasonographic investigation of these supra-aortic trunk vessels, including textbooks, journal articles, seminars, and manuals. This review has been compiled to familiarize physicians and sonographers with the relevant anatomy, pathophysiology, treatment, and diagnostic duplex surveillance of aortic arch vessel disease. Illustrative cases along with clinical rationale are discussed with the intent to facilitate the integration of arch vessel duplex imaging into the scope and practice of echocardiography.

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.

Doppler ultrasonography in suspected subclavian artery obstruction and in patient monitoring after subclavian stenting

PURPOSE

Subclavian or innominate artery (SIA) stenosis affects up to 5% of patients referred to coronary bypass grafting; it is symptomatic in less than half of these. This study aimed to assess the Doppler ultrasonography (DU) findings in SIA obstruction and patients' follow-up after percutaneous angioplasty (PTA).

METHODS

The study enrolled 118 patients (68 men, 50 women), aged 61.3 +/- 8.7 years, with suspected SIA obstruction, in whom peak systolic velocity (PSV) in the SIA and subclavian steal grade were assessed on DU and verified by quantitative angiography (QA). Serial follow-up DU was performed in patients treated with PTA.

RESULTS

Grade I-III of subclavian steal from the vertebral artery (VA) was found in 89.8% of patients. In the remaining 10.2% only a PSV increase in the SIA was observed. QA confirmed the presence of SIA obstruction in all patients (stenosis grade: 80.9 +/- 17.3%). In patients with one-sided SIA obstruction, the ultrasonographic steal grade correlated with the QA stenosis grade (p < 0.001, r = 0.648). Lack of subclavian steal was noted in the case of distal subclavian stenosis, VA obstruction, VA originating from the aortic arch, and bilateral SIA obstruction. Successful PTA was performed in 77 of 83 patients referred to that procedure. PSV was reduced from 4.4 +/- 1.2 (2.2-6.5) m/sec to 1.34 +/- 0.51 (0.5-2.5) m/sec and flow in the VA was normalized. During the mean follow-up time of 24.7 +/- 15.6 months, there was a gradual increase in the in-stent PSV as well as gradual VA flow alterations, resulting in symptom recurrence. More than a twofold PSV increase, compared with the post-PTA values, was an indicator of restenosis in 11 of 12 patients.

CONCLUSIONS

Careful DU evaluation enables the recognition of SIA obstruction in all patients. Ninety percent of them have subclavian steal correlating with the stenosis grade. Restenosis can be reliably detected with DU based on in-stent PSV and VA flow alterations.

The coronary-subclavian-vertebral steal syndrome (CSVSS)

OBJECTIVE

Reverse flow in the internal thoracic artery (ITA) after coronary bypass surgery due to an occlusion or severe stenosis of the subclavian artery is a rare situation. Symptoms can be recurrent and intermittent angina pectoris in the case of a coronary-subclavian steal (CSSS) or-in addition with cerebral symptoms-in the case of a coronary-subclavian-vertebral steal syndrome (CSVSS).

METHOD

We describe the cases of four patients with recurrent angina pectoris 5, 11, and 14 years as well as directly after coronary bypass surgery with LITA grafts to LAD. In two patients there was the additional aspect of vertebral steal symptoms with dizziness and intermittent drop attacks.

RESULTS

A PTA of the subclavian occlusions in three cases was not feasible, so that three patients were operated on by extrathoracal approach and carotido-subclavian bypass (CSB) in two cases, and local thrombendarteriectomy of the subclavian and vertebral artery (TEA)+ -patchplasty in one case. Patient 4 was treated by PTA and stent placement into the subclavian artery. Antegrade flow in all four LITAs could be achieved resulting in immediate relief from angina pectoris and cerebral symptoms. Patients 1 and 3 showed no further symptoms with equal BP of the upper extremities and anterograde flow in the LITA grafts and vertebral artery at 10-month follow-up. Patient 2 unfortunately died from an unrelated cause (asthmatic state) 4 months after the operation despite an uneventful recovery.

CONCLUSION

The occurrence of a CSSS or CSVSS after coronary bypass surgery with retrograde flow in the ITA graft (as described in our four patients) is a rare, but potentially hazardous, situation. If the subclavian occlusion is not amenable to endovascular strategies, the extrathoracal approach by CSB or local TEA and patchplasty provides an excellent means with good midterm and long-term results.