Angioplasty involves the use of a small balloon catheter, which is inflated to widen narrowed blood vessels in the heart. Between 40 and 50 percent of patients will require a repeat procedure because of re-narrowing (restenosis) of the artery.
Although the use of stents (metal scaffolds inserted in the artery) has reduced the frequency of restenosis to 25-35 percent, this procedure has similar limitations. Both these procedures can be thought of as causing a scar in the vessel which radiation may prevent.
Dr. Ian Crocker, Emory University School of Medicine in Atlanta, GA. reported on the six- month results of using beta radiation following balloon angioplasty to prevent restensosis study results at the 39th Annual Meeting of the American Society for Therapeutic Radiology and Oncology (ASTRO) October 20 in Orlando, FL.
"The chances of restenosis of the blood vessel in this pilot study was 15 percent, or about 1/3 the expected rate for this group of patients," according to Dr. Crocker. "Even more impressive was the fact that the late loss and late loss index were reduced by 85-90 percent by the addition of radiation." The "late loss" is the difference in the diameter of the vessel right after angioplasty compared to the diameter six months later.
Low dose beta radiation, as was used in this study, Dr. Crocker explained, led to no significant exposure to the patient or personnel. The procedure added only 5-10 minutes to the normal angioplasty, which general takes from one to two hours.
"Based on our findings," Dr. Crocker said, "the use of radiation therapy after angioplasty may reduce health care costs by reducing the number of repeat procedures."
Based on this study a multi-center clinical trial has been started which will include 1,100 patients in 26 different centers in the United States, Canada and Europe."
The American Society for Therapeutic Radiology and Oncology (ASTRO) is the largest radiation oncology society in the world, with some 4,000 members. As a leading organization in radiation oncology, biology and physics, the society's goals are to advance the scientific basis of radiation therapy and to extend the benefits of radiation therapy to those with cancer.