Primarily used in cardiovascular medicine, therapeutic angiogenesis refers to clinical experimentation processes using human growth factors as a treatment for inadequate blood and tissue perfusion. Doctors may opt to work with therapeutic angiogenesis following failure of traditional treatments for ischemic heart disease, peripheral arterial disease, and macular degeneration, as well as other disorders in which blood flow and tissue have deteriorated. The process may also help to repair chronically damaged tissue associated with cancer and arterial ulcerations, such as diabetes-related lower extremity ulcers or venous ulcerations of the leg. Although classified as experimental, this form of angiogenesis began to gain the respect of medical professionals near the end of the 20th century.
Angiogenesis alone is a naturally occurring process by which the body regenerates damaged blood vessels or tissue in response to trauma and disease. A desire to replicate this process led to the scientific identification of the cytokine protein vascular endothelial growth factor (VEGF), which is one of the main molecules responsible for signaling the human body when it's time to initiate tissue regeneration. This discovery gave the medical community the information necessary to begin developing therapeutic angiogenesis in a clinical setting. First used by Dr. Napoleone Ferrara in 1989 to treat age-related macular degeneration, use of the process quickly spread to additional disorders.
Since the discovery of therapeutic angiogenesis, scientists have identified several additional cytokine substances, including fibroblast growth factors (FGF), granulocyte colony stimulating factor, and placental growth factor, as well as many others. While some of these have a reputation for causing an undesirable increase in diseased cellular activity, others have the potential to stimulate the growth of damaged blood vessels in patients who suffer from cancer and numerous vascular diseases. In support of these potential benefits, several well-known organizations have conducted scientific trials focused on clinical uses for therapeutic treatments involving human growth factors. The VIVA trials by the Minneapolis Heart Institute Foundation showed a significant improvement in angina patients treated with high doses of VEGF, while trials conducted by St. Elizabeth's Medical Center revealed the capacity of VEGF in improving angiogenesis in patients who suffer from critical limb ischemia.
Therapeutic angiogenesis may remain in the experimental category for some time, as further tests are necessary to identify its long-term risks and benefits. The most pressing issues associated with the treatment involve determining the best manner of delivery, defining the proper dosage, and discovering which angiogenic growth factors work best for specific conditions. If these questions are answered satisfactorily, the therapy could become an important element of treatment plans for people with vascular diseases and other types of conditions that cause tissue damage.