A Creighton University School of Medicine researcher has received a $3.3 million, five-year grant from the National Institutes of Health to study what role adult stem cells might play in repairing damaged coronary arteries, a complication that often occurs in patients after they undergo angioplasty and stenting.

"Restenosis, a re-narrowing of coronary arteries in the heart, after balloon angioplasty and the placement of stents, is a serious problem. Drug-eluting stents can help reduce the occurrence of restenosis. However, there is a serious tradeoff.

Drug-eluting stents can lead to thrombosis (platelet deposits in the endothelial lining around the blood vessels that destroy the lining), which then requires longer periods of anti-platelet therapy. This therapy, in turn, can produce serious side effects, including nosebleed, upset stomach, nausea and diarrhea," said Devendra Agrawal, Ph.D., principal investigator and a professor of biomedical sciences, internal medicine and medical microbiology and immunology.

For the study, Agrawal and his co-investigators, Creighton cardiologist Michael Del Core and pathologist William Hunter will deliver adult stem cells (autologous mesenchymal stem cells), together with a novel gene, at the site of an interventional procedure in the coronary arteries of a pig model.

The goal is to determine whether the administration of adult stem cells, along with the gene therapy, is superior to using drug-eluting stents following angioplasty, said Agrawal, holder of The Peekie Nash Carpenter Endowed Chair in Medicine. If successful, he added, the treatment could even eliminate the need for stents.

Recent research has shown that angioplasty and stenting -- commonly used to open narrowed coronary arteries -- are not as effective as once thought.

In fact, a study involving more than 15,000 patients and published Nov. 28 online by the Archives of Internal Medicine, shows that it can even do more harm than good in some patients. According to the study, nearly one in 10 patients undergoing coronary angioplasty was readmitted to a hospital within 30 days, and these patients were at higher risk of death within one year.

With angioplasty, a catheter-guided balloon is inserted to open a narrowed coronary artery. A wire mesh stent is typically implanted during the procedure to keep the artery open.

Eleven to18 percent of all patients experience restenosis or a re-narrowing of the artery within three-four years, said Agrawal.

This is the second grant Agrawal has received in recent months to explore alternatives to stenting. The first grant totaled $2.58 million over four years.