Among 21,545 adult patients who underwent consecutive coronary angiography, 16 (0.07%) were found during their coronary arteriography to have a significant isolated stenotic lesion (luminal diameter narrowing of 50% or more) located at the left main coronary artery. The remaining major epicardial coronary arteries and their branches were free of disease. A strong predilection for the isolated lesion to occur at the ostium of the left main artery was found (12 patients). The most common presenting symptom was angina of less than 4 weeks' duration, although one third of the group was asymptomatic. Resting electrocardiograms were normal in 12 patients, while three patients had T wave inversion and another had nonspecific ST-T changes. Eleven patients exhibited severe stenosis, with eight having 70% to 89% stenosis and three having 90% to 95% stenosis. Five patients had 50% to 69% stenosis. No significant differences were found between patients with angina and patients without angina with respect to age, left ventricular end-diastolic pressure, left ventricular ejection fraction, and mean percent stenosis of the obstructive lesion. Despite the severity and the crucial location of the obstructive lesion, most patients with an isolated, significant left main stenosis appear to have a preserved left ventricular ejection fraction, normal wall motion, and no significant alteration of the left ventricular end-diastolic pressure.

Adult↗

PubMed1991

Complete left main coronary artery occlusion: angiographic evaluation of collateral vessel patterns and assessment of hemodynamic correlates.

An angiographic study of eight patients with total occlusion of the left main coronary artery identified six patients with chronic occlusion and two with acute complete occlusion. In each of six patients, there were two to six different intercoronary collateral pathways. Altogether, a total of 13 specific collateral channels were recognized. One patient had evidence of unique homocollaterals represented by enlarged vasa vasorum, which created a vascular cuff that surrounded a totally obstructed left main artery. The ventricular function and hemodynamic parameters in these patients not only depend on the collateral vessels but may also be affected by the severity of coronary artery disease in the artery that supplies collaterals.

Aged↗

PubMed1991

Absent left main coronary artery: angiographic findings in 83 patients with separate ostia of the left anterior descending and circumflex arteries at the left aortic sinus.

Among 20,332 adult patients who underwent consecutive cardiac catheterization and coronary arteriography, 83 (0.4%) were angiographically identified as having an absent left main coronary artery. The angiographic characteristics of this coronary anomaly include: (1) the presence of two well-separated coronary ostia at the left aortic sinus resulting in separate origin of the left anterior descending and circumflex arteries; (2) an increased incidence of left coronary dominance; (3) a higher (6%) than usual (0.5% to 1.5%) incidence of myocardial bridging; (4) lack of a high incidence of congenital heart anomalies; and (5) an incidence of atherosclerotic coronary artery disease similar to that of patients whose left main artery is intact. In 39% of the patients difficulties in selectively cannulating the separate ostium of the circumflex artery and adequately opacifying this vessel resulted in a need to change the diagnostic catheter size. Recognition of this coronary anomaly is needed to ensure accurate angiographic interpretation and is important for patients undergoing cardiac surgery to selectively perfuse these separate vessels during cardiopulmonary bypass.

Cardiac Catheterization↗

PubMed1991