Origin and length of left main coronary artery: its relation to height, weight, sex, age, pattern of coronary distribution, and presence or absence of coronary artery disease.

The distance from the base of the left coronary sinus to the origin of the left main coronary artery was measured in 54 patients. The length of the left main coronary artery and the pattern of arterial dominance were determined in the last 37 patients. These variables were correlated with height, weight, age, sex, and presence or absence of coronary artery disease. Average distance from the basis of the left coronary sinus to the origin of the left main coronary artery was 19.4 +/- 2.7 mm. Average length of the left main coronary artery was 9.7 +/- 4.3 mm. There was a large inherent variability between distance from the base of left coronary sinus to the origin of the left main coronary artery and height of the subjects. Other variables did not show positive correlation. Similar large variability was noticed between of the left main coronary artery and height of the subjects. Thus, from these observations it was not possible to predict the distance from the base of the left coronary sinus to the origin of the left main coronary artery or the length of the left main coronary artery using height or any other variable. The importance of these findings in relation to coronary angiography is discussed.