People who have had heart surgery often take blood-thinning drugs to prevent life-threatening blood clots from forming. But if these patients ever need surgery again, they face a dilemma. They must stop taking the anti-clotting medication several days before surgery to avoid bleeding to death in the operating room. Once off the medication, though, they risk a deadly blood clot. The ideal solution would be an anti-clotting drug that leaves the body quickly so patients can have surgery without delay. VOA's Carol Pearson reports just such a drug is on the horizon.
Heart stents open blocked arteries and restore blood flow. They can also help support weak arteries and keep them open. Stents are implanted during a common procedure called angioplasty.
During this procedure, the doctor threads a thin, flexible tube with a balloon or a similar device on the end through a blood vessel to the narrow or blocked artery.
After stenting, patients are put on a blood-thinning medicine to prevent clots in the stent. The problem comes when patients taking these drugs have to have heart surgery. Cardiologist Eric Topol sums up the dilemma.
“The stakes are really high once a stent’s been placed in an artery of the heart and if a stent clots it either results in a heart attack or the patient dying,” Topol said.
Dr. Topol is the director of the Scripps Translational Science Institute. He co-authored a study involving 200 patients who had heart stents and who needed open heart surgery. Half the group was given a placebo. The other half received a medication called cangrelor which patients receive intravenously.
"We were testing to see whether or not we could inhibit their platelets, which are the cells that form a blood clot," Topol said.
Cangrelor’s anti-clotting property loses effect within a few hours, so it can be discontinued just prior to surgery.
“The results were pretty striking on the side of being able to inhibit clotting. We were able to do that in all the patients, virtually, with this medicine cangrelor as compared to the placebo,” Topol said.
Not only were the patients able to have surgery sooner, Dr. Topol says, but they didn't have any trouble with bleeding.
"So now we have an intravenous medication that was tested which can be used in those days between stopping the oral medications and actually undergoing the major operation,” Topol said.
A report on the successful trial of the new anti-clotting drug, cangrelor, appears in the Journal of the American Medical Association.