Coronary Collateral Flow Index Is Correlated With the Palmar Collateral Flow Index

Objective: The extent of the collateral circulation varies between individuals which affects morbidity and mortality. Experimental data show that collateral coherence between different organs is strain-dependent. Whether this interrelation is also present in humans is unknown. This study investigates the relation between the palmar and the coronary circulation in patients with coronary artery disease and which factors possibly influence collateral development. Approach and Results: In 50 patients with a chronic total occlusion, both the coronary collateral flow index (CFI) and the palmar CFI was measured. The correlation between both indices was determined, together with the relation to clinical variables. Mean coronary CFI was 0.51±0.16, and mean palmar CFI was 0.82±0.13. The coronary and palmar CFI were significantly correlated (ρ=0.48, P =0.001). Coronary CFI was 22% lower in low palmar CFI patients (<0.82) as compared with high palmar CFI patients (0.43±0.12 versus 0.57±0.18, P =0.03). In multivariable analysis, coronary CFI was significantly correlated with the palmar CFI and the duration of angina pectoris. Coronary CFI was inversely correlated with peripheral artery disease and systolic blood pressure. Conclusions: The coronary CFI and palmar CFI are significantly correlated, implicating collateral coherence between vascular beds in humans.