In a new study reported in the journal Circulation, scientists are describing the first objective evidence that gene therapy successfully helped patients grow new blood vessels and significantly increased blood flow to heart muscle. The study found that the treatment both improved tissue that had suffered from restricted blood supply and rescued areas of the heart that caused pain even when the patient was at rest.
The study, conducted by researchers at Tufts University School of Medicine and St. Elizabeth's Medical Center, was conducted with 13 patients, all of whom had chronic chest pain and had failed balloon angioplasty, coronary bypass surgery, or both. The patients underwent an imaging exam to determine which areas of the heart were deficient in blood supply and a new cardiac mapping test that can distinguish between normal and blood-starved heart tissue. They were then given injections of DNA for a substance called vascular endothelial growth factor, or VEGF, directly into four sites in the heart muscle where blood supply was blocked or compromised.
Imaging and mapping studies were repeated after sixty days. Each test revealed that, on average, the amount of compromised heart tissue was substantially reduced. Post-treatment tests showed that in five patients, an area of heart muscle that was particularly damaged from lack of blood was completely revived. While these test results are promising, it is likely to be years before researchers know whether gene therapy, or angiogenisism, can predictably promote blood-vessel growth and provide a new tool in treating heart disease. For more information visit wvweb.com/news/JournalCirculation.