Frequency distribution of collateral flow and factors influencing collateral channel development - Functional collateral channel measurement in 450 patients with coronary artery disease

Objectives We sought to determine the pathogenetic predictors of collateral channels in a large cohort of patients with coronary artery disease (CAD). Background The frequency distribution of collateral flow in patients with CAD is unknown. Only small qualitative studies have investigated which factors influence the development of collateral channels. Methods In 450 patients with one- to three-vessel CAD undergoing percutaneous transluminal coronary angioplasty (PTCA), collateral flow was measured. A collateral flow index (CFI; no unit) expressing collateral flow relative to normal anterograde flow was determined using coronary wedge pressure or Doppler measurements through sensor-tipped PTCA guide wires. frequency distribution analysis of CFI and univariate and multivariate analyses of 32 factors, including gender, age, patient history, cardiovascular risk factors, medication and coronary angiographic data, were performed. Results Two-thirds of the patients had a CFI <0.25 and 40% of patients had a CFI <0.15, but only 10% of the patients had a recruitable CFI greater than or equal to0.4. By univariate analysis, the following were predictors of CFI greater than or equal to0.25: high levels of high-density lipoprotein cholesterol, the absence of previous non-Q-wave myocardial infarction, angina pectoris during an exercise test, angiographic indicators of severe CAD and the left circumflex or right coronary artery, as the collateral-receiving vessel. Percent diameter stenosis of the lesion undergoing PTCA was the only independent predictor of a high CFI. Conclusions This large clinical study of patients with CAD in whom collateral flow was quantitatively assessed reveals that two-thirds of the patients do not have enough collateral flow to prevent myocardial ischemia during coronary occlusion, and that coronary lesion severity is the only independent pathogenetic variable related to collateral flow. (J Am Coll Cardiol 2001;38: 1872-8) (C) 2001 by the American College of Cardiology.