Total coronary occlusion in chronic coronary artery disease

Abstract The hemodynamic consequence of chronic total occlusion of a coronary artery and the association of collaterals has not been well established. To examine this, 75 patients with at least one total occlusion of a major coronary artery were identified from among 267 patients undergoing selective coronary angiography. There was evidence of previous myocardial infarction in 49 (65%) of these patients. There was no intergroup (myocardial infarction versus no infarct) difference in terms of age, chronicity of angina prior to or stability of angina at selective coronary angiography, the number and distribution of total occlusions, or the extent of coronary disease. Furthermore, there was a high prevalence of angiographically demonstrated collaterals in both myocardial infarction and noninfarct patients (96% versus 98%). However, significantly greater left ventricular dysfunction, as determined by larger end‐diastolic and end‐systolic volumes (p<0.001), higher left ventricular end‐diastolic pressure (p<0.05), and lower ejection fraction (p<0.001) was found in the myocardial infarct group. We conclude that total occlusion of the major coronary artery occurs commonly in patients with chronic coronary disease, but is associated with myocardial infarction in only 65%. The presence of collaterals, the distribution of occlusion, and the extent of associated coronary disease do not distinguish patients with and without myocardial infarction. This suggests that the temporal course of oclusion and collateral development is a more important factor in the pathogenesis of iinfarction and its hemodynamic consequences.