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Electrocardiogram in a Man with Chest Pain and Widespread Atherosclerotic Disease

A 54-year-old man with dyslipidemia had smoked 1 pack of cigarettes per day for many years and recently had been experiencing chest pain on exertion and at rest. He came to the hospital because of a more severe episode of chest pain, and an electrocardiogram was recorded (Figure). He was on no medication. 
 
 
 
Figure 
 
Electrocardiogram recorded on admission. The rhythm is sinus arrhythmia at a rate of 99 beats/min. Striking ST-segment depression is present in all leads except aVR, aVL, and V1, and in each of those three leads there is ST-segment elevation, most marked ... 
 
 
 
Patients with ischemic symptoms at rest and ST-segment depression in 8 or more leads with reciprocal ST-segment elevation in leads aVR and V1 have a 70% likelihood of having severe left main or three-vessel coronary arterial narrowing (1, 2). Because the injury current caused by diffuse subendocardial ischemia engendered by severe left main coronary arterial narrowing is directed away from the left ventricular cavity and directly toward lead aVR, when ST elevation in aVR exceeds ST elevation in V1, the left main is likely the culprit artery (3). Furthermore, the magnitude of ST-segment elevation in lead aVR correlates directly with mortality in patients with their first acute non–ST-segment-elevation myocardial infarct (4). In patients with occlusion of the left main coronary artery, ST-segment elevation in both aVR and aVL (Figure) predicts increased mortality (5). 
 
Thus, our patient had electrocardiographic features suggesting left main coronary arterial disease and a poor prognosis. An increased serum troponin concentration (peak 0.58 ng/mL; reference, <0.05) and recurrent chest pain after coming to the hospital also indicated a high risk for an adverse outcome (6), and because high-risk patients benefit from an early invasive strategy (7, 8), he underwent cardiac catheterization and angiography. 
 
His left ventricular pressure was 140/12 mm Hg, and left ventriculography showed a normal-sized ventricle with anteroapical hypokinesis, an ejection fraction of 50%, and no mitral regurgitation. Coronary arteriography revealed a 95% narrowing of the distal left main coronary artery, luminal irregularities in the left anterior descending coronary artery, a 50% stenosis in the left circumflex coronary artery, and a 60% to 70% narrowing in the mid portion of the right coronary artery, which gave collaterals to the left anterior descending artery. An abdominal aortogram showed a 50% narrowing of the ostium of the right renal artery, complete occlusion of the proximal portion of the left common iliac artery with bridging collaterals, 75% narrowing of the proximal right common iliac artery by a complex plaque, and 70% narrowing at the ostium of the right internal iliac artery. The left subclavian artery had luminal irregularities, and the left internal mammary artery was free of disease. Balloon dilation and placement of a 10 mm × 4 cm stent completely eliminated the stenosis in the right common iliac artery, and through it a 40 cc intraaortic balloon was placed and pumping was begun. 
 
The following day the patient underwent three-vessel coronary arterial bypass grafting using the left internal mammary artery to the left anterior descending coronary artery and saphenous vein grafts to the first obtuse marginal branch of the left circumflex coronary artery and the posterior descending branch of the right coronary artery. The patient had an uneventful postoperative course and was discharged on the fourth postoperative day on metoprolol, simvastatin, and aspirin.