Formation and function of coronary collateral circulation and their influencing factors

Objective To clarify the formation and function of coronary collateral circulation (CCC) in coronary artery disease(CAD) patients with severe coronary artery stenosis and their influencing factors.Methods Coronary angiography was performed on 266 CAD patients with severe coronary stenosis. CCC formation was evaluated by Rentrop rating on those 266 patients and 401 severe stenosis arteries; while in CCC formed patients, CCC function was evaluated by Werner collateral collection (CC) rating. The formation, function of CCC and their influencing factors were analyzed and compared. Results CCC formation in those severe stenosis coronary arteries was related to the severity of coronary stenosis: the forming rate of CCC was 42.6% in vessels with 90%～94% stenosis (Group A), 56.9% with 95%～99% stenosis (Group B) and 93.0% with 100% stenosis (Group C)(p0.01). Between CCC forming and non-forming groups, there was no significant difference in age, gender, incidence of MI, hypertension and diabetes, history of smoking and serum levels of HDL-C and LDL-C (P0.05). In the CCC formation group, serum HDL-C level was the highest in the CC Grade 2 group (according to Werner function rating) and the lowest in the CC Grade 0 group (P0.05). Whereas, LDL-C level was the lowest in the CC Grade 2 group and the highest in the CC Grade 0 group (P0.05).Conclusion Severity of coronary stenosis was the major influencing factor in CCC formation and function, and the rate of CCC formation increased with the exacerbation of coronary stenosis. Serum HDL-C and LDL-C level had no relationship with CCC formation,but related to CCC function. Better CCC function was found in patients with high level of HDL-C whereas the patients with high level of LDL-C had spoiled CCC function.