[The necessary conditions of chronic total occlusion of all three coronary vessels--the relationship between portions of coronary occlusion and collateral vessels].

This study was performed to define the conditions present in chronic total occlusion of all three coronary vessels. Each left descending coronary artery (LAD), left circumflex branch (LCX) and right coronary artery (RCA) was totally occluded angiographically in 5 patients (mean age 64, male 3, female 2). Four of them had history of myocardial infarction. Anginal type was effort angina in all patients, and two cases showed unstable angina. Good collateral supply was found in the distal portions of occluded vessels from proximally located branches, such as Conus branch, Right ventricular branch, Septal branch and Left atrial circumflex branch. Almost all of the occlusions were located at mid portions (13/15: mid, 2/15: proximal). Ejection fractions (EF%) of the 5 patients were 70%, 69%, 60%, 28% and 22% respectively. EF was correlated with the degree of collateral supply and one of them (22%) ended in sudden death. These findings suggest that the mid portion occlusion, good collateral supply and a long history of angina pectoris are important factors involved in chronic total occlusion of the three coronary vessels.