A 58-year-old veteran from San Antonio with severe coronary artery disease — no longer treatable by conventional procedures — today underwent a new procedure called angiogenesis that makes tiny vessels grow inside the heart muscle, increasing blood flow to the heart. The patient, who requested that his name not be used, is the first to receive this novel form of treatment by faculty physicians of The University of Texas Health Science Center at San Antonio (UTHSCSA) who also are on the medical staff of the South Texas Veterans Health Care System, Audie Murphy Division.
"He is receiving injections of Fibroblast Growth Factor, or FGF, in five different regions of coronary blockages," said Miguel Zabalgoitia, M.D., professor of medicine. "We are doing this procedure during a standard cardiac catheterization. The catheter is introduced through the femoral artery and advanced to the origin of the coronary arteries that have disease. The drug is the unique part. FGF promotes the proliferation of new cells that grow new vessels called collaterals, which will supply blood to blocked areas."
The UTHSCSA-VA team is one of 30 testing the drug nationwide. The San Antonio study is conducted by Dr. Zabalgoitia, Dr. Robert Chilton, associate professor of medicine at UTHSCSA, and Dr. Nilesh Goswami, interventional cardiology fellow. Heather Moore, R.N., and Michael Lujan are the study coordinators. All also serve on staff at the VA hospital.
Before the catheterization, the patient's cardiovascular fitness was measured in a series of stress tests on a treadmill. The same tests will be repeated at six and 12 weeks after FGF therapy to determine the drug's efficacy. "We want to see if the patient can walk for a longer period on the treadmill without suffering electrocardiographic changes," Dr. Zabalgoitia said. "The effectiveness of this drug will be based on the comparison between the baseline and post-procedure treadmill tests."
Berlex Laboratories of New Jersey makes FGF and is funding the study. The drug is a combination of a modified adenovirus and the growth factor. The adenovirus that produces the common cold is the vehicle that transports the FGF into the cells. "The common cold virus has the capacity to enter cells," Dr. Zabalgoitia said. "We are taking advantage of that property to get FGF inside the cells of the heart muscle. Once it is inside, the FGF communicates with the cell nucleus to produce proteins that promote the growth of new endothelial cells."
The study is randomized and double-blind, which means patients and investigators will not know whether the patients received a placebo (inactive agent), high-dose FGF or low-dose FGF. The drug has been tested in two previous human trials enrolling a total of 170-200 patients. Patients undergo extensive medical and laboratory testing before entering the study.
Side effects in the first trials have been occurrences, such as development of heart rhythm irregularities or bleeding, that are standard with heart catheterizations.
"FGF is expected to help patients who have significant coronary artery disease that can no longer be managed through surgical bypasses or angioplasties with or without stents," Dr. Zabalgoitia said. "Many times these patients are left with multiple drug therapy and they continue to have chest pain and shortness of breath with normal activities and sometimes even at rest."