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 C AD is unknown. Only small qualitative studies have investigated which facto rs influence the development of collateral channels. Methods In 450 patients with one- to three-vessel CAD undergoing percutaneo us 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 dist ribution analysis of CFI and univariate and multivariate analyses of 32 fac tors, 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 <similar to>40% of p atients had a CFI <0.15, but only <similar to>10% of the patients had a rec ruitable CFI greater than or equal to0.4. By univariate analysis, the follo wing were predictors of CFI greater than or equal to0.25: high levels of hi gh-density lipoprotein cholesterol, the absence of previous non-Q-wave myoc ardial infarction, angina pectoris during an exercise test, angiographic in dicators of severe CAD and the left circumflex or right coronary artery, as the collateral-receiving vessel. Percent diameter stenosis of the lesion u ndergoing PTCA was the only independent predictor of a high CFI. Conclusions This large clinical study of patients with CAD in whom collater al flow was quantitatively assessed reveals that two-thirds of the patients do not have enough collateral flow to prevent myocardial ischemia during c oronary occlusion, and that coronary lesion severity is the only independen t pathogenetic variable related to collateral flow. (J Am Coll Cardiol 2001 ;38: 1872-8) (C) 2001 by the American College of Cardiology.