Incidence and angiographic predictors of collateral function in patients with stable coronary artery disease scheduled for percutaneous coronary intervention.

OBJECTIVES: To investigate the incidence and angiographic predictors of functional collateral perfusion in patients with stable coronary artery disease, scheduled for elective PCI. BACKGROUND: Functional collateral perfusion is defined as a Pw/Pa ratio>or=0.24. Since this can only be measured intracoronary, it is important to investigate baseline clinical and angiographic predictors for functional collateral perfusion. METHODS: Collateral perfusion was measured during balloon inflation, with the use of a pressure-monitoring guide wire. Baseline clinical and angiographic characteristics were analyzed and collateral grading was done according to Rentrop's classification for coronary angiograms. RESULTS: Functional collateral perfusion was found in 40 of the 89 patients (45%). Angiographic signs of collaterals (Rentrop>or=1) were present in 15 of the 89 patients. Of the 40 patients with the functional collateral perfusion 11 patients (28%) had Rentrop>or=1; of the 49 patients without functional collaterals there were 4 patients with Rentrop>or=1 (8%) (P=0.02). There were no significant differences in baseline clinical characteristics or in other angiographic characteristics. CONCLUSIONS: In patients with stable coronary artery disease scheduled for elective PCI, 45% have functional collaterals. Rentrop's angiographic classification can be used to predict the presence or absence of functional collaterals, however with a rather modest positive and negative predictive value.