FGF-I, a human growth factor obtained through genetic engineering, was used in 20 patients with some form of ischemic or coronary heart disease, which results from blockages in the vessels leading to and from the heart. By injecting the growth factor near the blocked vessels, the scientists were able to induce neoangiogenesis -- the process by which the body can grow its own new capillary network to bypass occluded vessels.
"This capillary network is a true de novo vascular system," says Thomas-Joseph Stegmann, M.D., head of the department of thoracic and cardiovascular surgery at the Fulda Medical Center, Fulda, Germany. "We were able to use the recognized physiological effects of FGF-I to induce neoangiogenesis in the human ischemic heart."
As early as four days after application of FGF-I, the vascular structure around the diseased vessels was completely altered in all 20 of the patients. Like the spokes of a bicycle wheel, the new capillary vessels radiated outward from the point of injection, resulting in a twofold to threefold increase in blood flow to the heart, says the study's lead author.
Researchers found, on average, the ejection fraction of the 20 patients improved from 50.3 percent to 63.8 percent in the three years following the procedure. Ejection fraction measures how much blood leaves the heart with each beat and indicates how well the left ventricle -- the heart's main pumping chamber -- is functioning.