EFFECT OF BASIC FIBROBLAST GROWTH-FACTOR ON MYOCARDIAL ANGIOGENESIS INS DOGS WITH MATURE COLLATERAL VESSELS

Objectives. We sought to evaluate the potential of basic fibroblast gr owth factor (bFGF) to enhance coronary collateral perfusion in dogs wi th chronic single-vessel coronary occlusion. A secondary goal was to e xamine whether the salutary effects of bFGF treatment, previously prov ed effective in the short term, would be maintained in the long term ( 6 months). Background. bFGF, an angiogenic growth factor, is currently the subject of a Phase I trial in patients with ischemic heart diseas e. It has been shown to promote collateral development in dogs with pr ogressive coronary occlusion when given during the period of natural c ollateralization. The effect of bFGF on quiescent collateral vessels, a subject of significant clinical importance, is uncertain. Methods. D ogs were subjected to ameroid-induced occlusion of the left circumflex coronary artery and randomized to bFGF (1.74 mg/day for 7 days), a re gimen previously proved effective, or to saline solution. Maximal coll ateral perfusion was assessed 6 months later, and the dogs were reassi gned to a course of bFGF or saline solution. Collateral perfusion was reevaluated after the second treatment course. Results. At 6 months, c ollateral function was identical in the groups treated initially with bFGF and saline solution. The subsequent course of bFGF did not induce further collateralization. Conclusions. Although we previously demons trated the salutary effects of this bFGF regimen in the short-term (5 weeks), collateral how in control dogs reached parity with that of bFG F-treated dogs after 6 months. bFGF; did not induce further collateral ization in dogs,vith mature collateral vessels, underscoring the primi ng role of ischemia for bFGF-induced collateral development. (C)1997 b y the American College of Cardiology.