Total occlusion of the left main coronary artery: A clinical, hemodynamic and angiographic profile

Abstract

Although left main coronary artery stenosis has been extensively revicwed, total occlusion of the left main coronary artery has received scant attention. Six patients were diagnosed at cardiac catheterization as having total occlusion of the left main coronary artery over a period of seven years at two institutions. They ranged in age from 32 to 72 years, and all had symptoms ranging from NYHA Class 1-IV at initial presentation. One patient died three days after coronary artery bypass graft surgery. Of the remaining five, two treated medically are alive four and 40 months after catheterization, and three treated with coronary artery bypass graft surgery are alive three, 66 and 68 months after catheterization. Electrocardiogram showed prior myocardial infarction in three patients, stress tests were positive in three of four patients, and hyperlipidemia was present in the five tested. In the three patients without prior myocardial infarction, left ventricular function was preserved (ejection fractions = 0.52, 0.55 and 0.64; left ventricular end-diastolic pressures = 6, 9 and 14 mm Hg). Injection of the right coronary artery in this group revealed extensive collaterals filling the left coronary artery. The three patients with prior myocardial infarction had impaired left ventricular function (ejection fractions = 0.18, 0.30 and 0.33; left ventricular end diastolic pressures = 26, 35 and 35 mm Hg) and sparse intercoronary collaterals. Patients with total occlusion of the left main coronary artery have a varying clinical presentation and may have prolonged survival. In patients with good collaterals, left ventricular function may be preserved.