Determinants of regional myocardial function in patients with chronic significant coronary stenosis or occlusion

Background: Our aim was to study the effect of collateral flow, stenosis severity, antegrade flow, and location of the lesion on regional myocardial function in patients with chronic left anterior descending (LAD) coronary artery disease. Methods and Results: Seventy-four patients who underwent coronary angiography and ventriculography were divided into three groups: group A (n = 9), patients with normal coronary angiogram and ventriculogram; group B (n = 32), patients with LAD stenosis >75%; and group C, 33 patients with LAD occlusion. The effect of collateral flow, stenosis severity, location, and antegrade flow on regional myocardial function in the LAD territory was studied. Regional function was impaired in both groups B and C. In group B, univariate analysis confirmed that antegrade flow had a significant effect on regional function (p <0.02). With the use of multiple regression, none of the other variables had an additional independent effect. In group C, no significant correlation was found between regional function and the study variables by univariate analysis; however, multiple regression revealed a significant correlation between anterobasal function, the lesion site (p = 0.01), and collateral flow (p = 0.02). Conclusions: In patients with LAD stenosis, antegrade flow has the strongest effect on regional myocardial function, with no additional effect of visible collaterals. In patients with LAD occlusion, both angiographic collateral flow and the site of the lesion have a significant effect on the function of the anterobasal area.