Individuals with moderate to severe chest pains (angina) who have not found relief from medication may benefit from a new gene therapy approach being used by cardiologists at Rush University Medical Center to grow new blood vessels in the heart.
The phase II clinical research study uses vascular endothelial growth factor-2 (VEGF-2) in the form of a solution containing a DNA plasmid that is delivered using catheterization to heart tissue that has been damaged from insufficient blood flow.
Once the catheter reaches the targeted site inside of the heart, the VEGF-2 is injected into the heart muscle region with inadequate blood supply. The DNA plasmid is then taken up by the middle muscular layer of the heart wall near the injection site. Inside the cell, the DNA encoded VEGF-2 expresses itself which in turn stimulates the growth of new blood vessels by promoting the proliferation of endothelial cells in the heart.
New blood vessels are required to provide oxygen-carrying blood to heart muscles to compensate for the blocked heart arteries. The subsequent, improved blood flow relieves the painful symptoms of angina.
"The process of growing new blood vessels, or angiogenesis, should occur over the course of four to eight weeks following the procedure which is done in the cardiac catheterization lab at Rush," said Dr. Gary L. Schaer, the principal investigator of the trial at Rush and director of the Rush Cardiac Catheterization Labs. "The patient goes home the next day." Several patients have received the gene therapy and all are doing well.
Individuals who may be candidates for this gene therapy study trial must have moderate to severe angina, but cannot also be candidates for treatment using angioplasty or bypass surgery. Angioplasty involves a catheterization with a balloon-like device that opens blocked arteries, while bypass surgery requires open-heart surgery to place veins removed from the patient's leg or arteries taken from the patient's chest wall or arm to "bypass" the blocked blood vessels.