New Blood Vessels Grown
In Humans Hearts
By June Preston

ATLANTA (Reuters) - Researchers using a naturally occurring growth hormone have successfully grown new blood vessels in heart patients who could not withstand bypass surgery or balloon angioplasty, a scientist said Monday. The new blood vessels were healthy and took over the function of diseased vessels in seven of 15 study participants, said Dr. Timothy Henry, of the Hennepin County Medical Center in Minneapolis, Minnesota, at a meeting of the American College of Cardiology.
The achievement could spell relief for as many as 600,000 people a year who suffer angina or leg clots due to blocked vessels, another researcher said. Henry said it was too early to tell whether the technique would benefit many people. ``I look at this as sort of a new frontier,'' he said. ''It's like when we first started doing bypass, when we first started doing angioplasty. We have a new treatment, and now we're trying to figure out how it works, how much to give.''
Henry said the goal in using the vascular endothelial growth factor protein was to enhance the body's natural mechanism of new blood vessel growth. The 15 patients in the trial had significant chest pain and were not candidates for coronary bypass surgery or angioplasty.
The researchers wanted to know how much of the protein patients could tolerate, because at high doses it was known to cause a drop in blood pressure. Henry said, however, lower doses were ``very well tolerated'' with no significant side effects. He said in seven of the 15 study participants a nuclear stress test showed clear improvement in blood flow soon after the protein was administered. Sixty days later, five of the seven had new blood vessels that took over the function of diseased vessels.
Dr. Michael Mann, a vascular specialist from Harvard University, said the work of the Minnesota scientists marked the first attempt to apply what is known about the molecular biology of coronary artery disease to human patients.
``Laboratory and animal studies have suggested this molecule may help patients with inadequate blood supply to the heart, especially patients for whom established therapy, such as surgery or angioplasty, cannot be performed,'' Mann said.
He said up to 600,000 people a year could benefit from the technique but the research involved too few patients over too brief a time to draw any conclusions about the therapy. Both scientists said the therapy would likely prove a useful adjunct to traditional treatments.

Email Homepage