Keywords: subclavian artery stenosis – coronary artery bypass grafting Introduction The current practice of total arterial revascularization, sometimes using `T' or `Y' grafts off the internal thoracic artery, is based on normal in¯ow into the subclavian and internal thoracic arteries. Undiagnosed signi®cant nar- rowing of the left subclavian artery (LSCA) may result in coronary hypoperfusion following myocardial revascu- larization, 1–3 the consequences of which may be cata- strophic. 4 In the past two years the authors have experienced two cases of persistent ischemia immediately after coronary artery bypass grafting (CABG) using the left internal thoracic artery. Postoperative catheterization revealed >70% stenosis in the proximal LSCA in both patients. They underwent successful balloon angioplasty of the narrowed segments followed by stent implantation. However, both patients died, one due to intractable cardiogenic shock and the other due to aspiration pneumonia. Routine injection into the osteum of the LSCA as part of the initial diagnostic angiography can detect a potentially lethal condition in the subclavian– mammary artery distribution. The following case is an example of the importance of such injection. Case report A 66-year-old male patient was referred for CABG after recent non-Q-wave myocardial infarction (MI). His medical history was signi®cant for non-Q-wave MI in 1997 and worsening angina pectoris before the more recent MI. He also had peripheral vascular disease and hypertension. Coronary angiography disclosed severe triple-vessel disease, and left ventriculography showed moderately reduced systolic function with anterior hypokinesia. No attempt to demonstrate the origin of the LSCA was made. On admission, blood pressure in the right arm was 15 mmHg higher than in the left arm and auscultation revealed a harsh murmur over the base of the neck, maximal at the area posterior to the left clavicle. These physical ®ndings were overlooked prior to the diagnostic cardiac catheterization. Doppler ¯ow examination con®rmed the presence of signi®cant pressure gradient across the origin of the LSCA, with no-¯ow in the left vertebral artery. Another catheteriza- tion was therefore required. Injection into the LSCA (Figure 1(A)), which could easily be added to the ®rst catheterization, demonstrated signi®cant stenosis in the LSCA proximal to the origin of the left vertebral artery, with a peak-to-peak gradient of 30 mmHg. Balloon angioplasty with stent implantation was performed (Figure 1(B)) to allow utilization of the left internal thoracic artery during the planned operation. The patient underwent an uneventful CABG using his left internal thoracic artery. Discussion The prevalence of LSCA stenosis is relatively low. 5 However, among patients with peripheral vascular The signi®cance of subclavian artery injection prior to surgical myocardial revascularization Amir Elami, Niv Ad and Gideon Merin Department of Cardiothoracic Surgery, Hadassah University Hospital, Jerusalem, Israel Correspondence: Amir Elami MD Department of Cardiothoracic Surgery POB 12000 Jerusalem, IL-91120, Israel Tel: () 972 2 677 6960 Fax: () 972 2 643 8005 E-mail: eamir@md2.huji.ac.il Received 22 August 2002 Accepted 5 September 2002 Successful arterial revascularization using the internal thoracic artery is dependent on unobstructed in¯ow through the subclavian artery. Systematic physical examination should discover subclavian stenosis; however, simple routine injec- tion into the ori®ce of the subclavian artery during the diagnostic catheteriza- tion may avoid a catastrophic outcome. (Int J Cardiovasc Intervent 2003; 5: 81–83) International Journal of Cardiovascular Interventions 2003 1, 8183  2003 International Journal of Cardiovascular Interventions. All rights reserved. ISSN 1462-8848 81 DOI 10.108014628840310003271 Case report