A new, different kind of stent brought relief by diverting blood to oxygen-starved heart muscle to people suffering from refractory angina, a kind of heart-related chest pain for which there currently is no effective treatment.
"An effective treatment for refractory angina is definitely needed," said Dr. Deepak Bhatt, associate director of the Cleveland Clinic cardiovascular coordinating center, "because it now affects at least 500,000 Americans, and the number is growing.
"A very substantial portion of these folks I see have no option," Bhatt said. "We've tried everything there is to be tried, and they continue to have chest pain. There is an unmet need for better therapies for this unstable angina."
A conventional stent is a flexible tube implanted in an artery to keep it open. The new stent is designed to partially block a coronary blood vessel so that blood is diverted to areas of the heart muscle that are in pain because of inadequate blood supply.
"The new stent is an hourglass-shaped, stainless steel, balloon-expandable stent delivered on a proprietary catheter," said Dr. Shmuel Banai, an interventional cardiologist at Tel Aviv Medical Center. The stent partially restricts the flow of blood draining from the heart by narrowing the coronary sinus, a vein that collects blood from the heart, to a diameter of three millimeters.
Researchers studied the results of implantation of the stent in 15 patients with refractory angina in Germany and India. The angina score measuring pain improved in 12 patients with echocardiograph and computed tomography showing a reduction in the ischemic area of the heart.
"There were no total occlusions, clotting or other complications noted at the end of the trial, and that is still the case two years out," Banai said.
Further Study Needed
The new report is "intriguing" and "provocative," Bhatt said, but the number of patients in the study was small, and there was no control group. "A placebo effect can occur," he said, so that just the thought of having an effective treatment can bring improvement. "These folks have no hope, so if you offer some hope, they can respond positively," Bhatt said.
Still, the concept definitely is worthy of further study," Bhatt said.
Dr. Gregory Barsness, assistant professor of cardiology at the Mayo Clinic in Rochester, Minnesota, said that while the trial study has not had complete follow-up, it is a "novel strategy that at least has been shown to be safe in a small group of patients.
"Having refractory angina does not necessarily increase the risk of death," Barsness said, "but these people certainly are suffering greatly. This population of patients with refractory angina is growing and will continue to grow as the population ages. Any strategy that improves the quality of life without morbidity and mortality would certainly be welcome."