Influence of clinical and angiographic factors on development of collateral channels

Background The degree of coronary collateralization is believed to be relat ed to several clinical and angiographic factors. The duration and frequency of angina may be important factors in determining development of collatera l channels. Objective To assess these factors for a consecutive series of patients susp ected to have coronary artery disease. Methods Patients without at least one stenosis of < 50% and patients who ha d previously undergone bypass surgery were excluded from our study. Severit y of stenosis was quantified by digital analysis, antegrade flow in terms o f TIMI grade, and collaterals using the Rentrop classification. Results We reviewed 106 patients [mean age 61 years (range 35-84), 77.6% me n], Of these, 22 (21%) had presented with an acute coronary syndrome on thi s admission, whilst 46 patients (43%) had previously had an acute coronary syndrome, Collaterals were more likely in patients with stenoses of > 90% ( Spearman correlation 0.65, P < 0.001) in patients with lower than normal TI MI flow grade (Spearman correlation 0.86, P< 0.01) and were related to regi ons of hypokinesis (Spearman correlation 0.35, P< 0.01), Significant collat erals were present in 14 patients (13%) despite their having TIMI grade II/ III flow, Two of these patients had grade 2/3 collaterals with TIMI grade I I/III antegrade flow, Degree of collateralization was not related to chroni city and frequency of symptoms, age, risk factors for atherosclerosis and n ature of presentation (i.e. acute or stable symptoms). Conclusion The likelihood of coronary collateralization cannot be prospecti vely predicted from clinical history alone, but appears to be largely a fun ction of severity of stenosis and level of antegrade flow. A few patients d evelop high-grade collateral channels despite the presence of good antegrad e flow, Coronary Artery Dis 11:573-578 (C) 2000 Lippincott Williams & Wilki ns.