Recently, a number of growth factors including basic fibroblast growth factor (bFGF) have been shown to promote angiogenesis in vivo. In this study, we evaluated dose-dependent effect of bFGF administration in the setting of chronic myocardial ischemia. A total of 18 Yorkshire pigs subjected to ameroid occluder placement on the left circumflex artery were randomized to treatment with 10 (n = 6) or 100 μg (n = 5) of bFGF incorporated into heparin-alginate microspheres or inactive control pellets (n = 7). Eight weeks later, all animals underwent angiographic evaluation of collateral development as well as studies of coronary flow and global and regional left ventricular function. Both bFGF groups had significantly higher angiographic collateral index, TIMI flow scores and coronary flow in the ameroid-compromised territory compared with controls. Left ventricular function studies demonstrated improved global and regional function in both fibroblast growth factor groups with significantly better preservation of regional wall motion in high dose (100 μg) bFGF animals. We conclude that local perivascular delivery of bFGF results in significant improvement in myocardial function in the setting of chronic myocardial ischemia.