Abstract:

Objective To analyse the differences of collateral vessel, ventricular segmental wall motion and ejection fraction between patients with chronic total coronary occlusion (CTO) and myocardial infarction and CTO with nonmyocardial infarction. Methods Two hundred and fifty-six patients diagnosed as CTO (occlusion duration ≥ 3 months) were retrospectively analysed of medical history, myocardial enzyme pedigree, electrocardiogram, coronary artery CT and coronary arteriography, and were divided into myocardial infarction group（n=138） and non-myocardial infarction group(n=118). The differences in general conditions, location distribution and extent of CTO, lesion distribution and degree of non-occlusion coronary artery, collateral vessel Rentrop grade, segmental ventricular wall motion and ejection fraction on echocardiography were compared between these two groups. Results There was no significant difference in general conditions, location distribution and extent of CTO, lesion distribution and degree of non-occlusion coronary artery and collateral vessel Rentrop grade between these two groups（P>0.05）. Compared with non-myocardial infarction group, the prevalence of normal segmental ventricular wall motion and ejection fraction in myocardial infarction group was significantly lower, while those of akinesia and paradoxical motion were significantly higher (P<0.05). Conclusion There is no significant difference in collateral vessel grade of Rentrop classification between myocardial infarction and non-myocardial infarction in myocardium supplied by occluded artery with CTO duration beyond 3 months. Although collateral vessel can prevent myocardium from myocardial infarction, its protective effects on segmental wall motion and ejection fraction are limited.

Key words: chronic total coronary occlusion, myocardial infarction, collateral vessel, segmental ventricular wall motion, ejection fraction