Myocardial ischaemia due to stenosis of the subclavian artery

The internal thoracic artery is often used for reconstruction of coronary arteries. In a proportion of cases the reasonfor bypass failure (internal thoracic artery – coronary artery) is abnormal blood flow in the subclavian artery resultingfrom its stenosis. The stricture can result from post-surgery progression of atherosclerosis or could have been presentand undiagnosed already when cardiac surgery was performed. This may result in exercise angina or even acute coronarysyndrome. Interventional intervention is inevitable in these cases. An 84-year-old man was admitted for unstableangina 7 years after coronary artery bypass grafting (CABG) from the internal thoracic artery to the left anteriordescending branch of the left coronary artery. In spite of medical treatment the symptoms did not recede and coronaryand bypass angiography was performed on the 4th day of hospitalization, revealing multiple stenoses of thecoronary arteries and severe stenosis of the left subclavian artery. Moreover, the symptoms subsided only slightlyafter angioplasty of the circumflex branch of the left coronary artery. For this reason, angioplasty of the left subclavianartery with stent implantation, widening of the right coronary artery aortic opening, and angioplasty of the leftcoronary artery trunk and of the circumflex branch at its origin were performed. These procedures resulted in completecessation of angina, while the patient also observed significant improvement of his left upper limb performance.The coronary-subclavian steal syndrome is defined as reduced flow through the bypass (internal thoracic artery –coronary artery) or reversed flow through the bypass, as a result of the narrowing of the proximal part of the left subclavianartery. In most cases the symptoms are stable and chronic, but in some patients an acute coronary syndromecan develop. Additionally, there are usually disturbances of the left upper limb perfusion. Routine blood pressuremeasurement on both arms is believed to identify a group of patients with high probability of subclavian artery stenosis,who may benefit from supplementation of coronary angiography with aortic arch imaging. Traditional surgicalmethods of treatment for subclavian-coronary steal syndrome include bypass between the left common carotid andleft subclavian artery. However, intravascular angioplasty with stent implantation is a contemporary method of choice.Intravascular methods allow simultaneous correction of coronary vessels when there is a recurrent stenosis.