A UAB clinical trial has shown favorable results of a new technique in the treatment of patients with repeat narrowing of a coronary artery following the placement of a coronary stent — the condition recently brought into the limelight by the nation's vice president.
The initial findings were presented Sunday, March 25, at the American College of Cardiology meeting in Orlando, FL.
Primary investigator Ming Liu, MD, interventional cardiologist and UAB associate professor, said the early results are very promising in the treatment of restenosis, or the renarrowing of an artery. Restenosis occurs in approximately 20 to 30% of patients who receive coronary stents, the mesh scaffolding-like devices used to prop open blocked arteries. The results are particularly significant among patients whose blockages are shorter in length.
Researchers treated 46 patients diagnosed with in-stent restenosis by first using a catheter procedure and a small balloon device to dilate the plugged artery. Then, using a special catheter, they injected a diluted ethyl alcohol solution into the injured area of the artery before propping it open with another stent.
Typically, Liu explained, restenosis is associated with an increase in the number of cells growing within the stent caused by an increased rate of cellular division, presumably the body's mechanism for repairing damaged tissue. The alcohol molecule is known to slow down or decrease cell division. The study's primary objective was to evaluate the efficacy of the alcohol molecule at retarding or preventing the in-stent cell growth.
After a one-year follow-up, only 1 of the 15 patients with lesion length shorter than 10 mm required a repeat procedure, however 7 of the 14 with lesion length longer than 10 mm required repeat procedures. Liu explained longer lesions require longer stents, result in larger areas of damaged tissue and have more significant chances of restenosis. However, he said according to the current literature, shorter lesions have less chance of restenosing, with a 15 to 20% chance of repeat blockage. "In our study, by using the alcohol solution treatment, we dropped that to 7%.”
The study calls for a larger, randomized trial using a control population before any conclusive data can be drawn, Liu said. However, these initial results indicate that alcohol treatment may be one of the many up-and-coming treatments that could one day be added to the arsenal to prevent restenosis.