New Technique Helps Heart Patients Grow Blood Vessels

	November 2, 1999 - Scientists have developed a capsule that delivers
growth factor to the heart to help restore blood flow. The time-release
capsule contains basic fibroblast growth factor. It is implanted near the
heart to stimulate the growth of new blood vessels. This was reported in the
November 2 edition of the journal Circulation.
	Bypass patients receive new blood vessels grafted from vessels in
their own legs. This will likely remain the preferred treatment for patients
needing coronary bypass surgery but some patients are not good candidates for
such grafts. They may suffer from severe blood-vessel damage or deposits in
blood vessels; or the blood vessel that is blocked in the patient may be too
small for a bypass operation to work.
	Each of the 24 patients in the study had blocked arteries near the
heart, which could not be repaired with bypass surgery. Eight received 100
micrograms of growth factor; eight received 10 micrograms; and the rest
received "dummy" capsules, which contained no active treatment. All patients
had 10 capsules implanted directly next to the blocked artery.
	The researchers used a stress test to analyze the amount of blood
flow the heart was receiving in each patient, 3 months after the procedure.
The blood flow in patients who got the placebo capsules worsened after the
procedure. Blood flow in patients in the 10 microgram group stayed the same.
However, those in the high-dose group showed blood-flow improvement.
	Sixteen months after surgery, the amount of chest pain each patient
had was assessed. Chest pain following surgery is an indication that blood
flow has not been restored to the heart. Four patients had chest pain but none
in the highest dose group experienced chest pain.
	"Patients getting the highest dose of growth factor showed
improvement in blood supply and heart function," said Dr. Michael Simons, the
study author. "While the number of patients is small, we clearly saw an effect
with the 100 microgram treatment group," Simons said.
	"The results appear favorable, but the number of patients is quite
small," said Dr. Valentin Fuster. "We need a large trial and long follow-up"
to see how effective this is in the long run," Fuster said. "This is an
advance, but there is still a long road in front of us."
	The time-release capsules are a new approach to introducing the
protein. Other methods, such as injections, have been tried with less success.
Widespread use of angiogenesis proteins (growth factor) to combat heart
disease is still years away.

Circulation (1999;100:1865-1871)