Modifying the order in which carotid stenting and balloon angioplasty is performed could also alter risk of stroke complications, according to the investigators of the Carotid Revascularization Endarterectomy versus Stenting Trial (CREST) sub-study to be presented today at the SCAI 2013 Scientific Sessions.
CREST is the largest, prospective randomized study that compared angioplasty and stenting of the carotid artery in the neck to surgery (carotid endarderectomy), the standard treatment. Carotid stenting is currently only available as a treatment option for patients who cannot undergo surgery. The objective of this sub-study was to evaluate whether undergoing angioplasty post-carotid stenting increases the risk of complications such as stroke.
“Carotid stenting is the subject of ongoing research because it provides a less invasive treatment option, which is often necessary for patients who are too sick to undergo surgery,” said Mahmoud B. Malas, M.D., lead author of the sub-study and associate professor of surgery at Johns Hopkins University and chief of endovascular surgery at Johns Hopkins Bayview Medical Center in Baltimore. “These results show performing balloon angioplasty after stenting significantly reduced the risk of those same arteries narrowing again, but may also increase, though not significantly, the risk of stroke.”
Of 1,109 patients in CREST who underwent carotid artery stenting, 69 patients underwent balloon deployment before the stent was implanted, 344 underwent balloon deployment after the stent was implanted and 696 patients had balloon angioplasty before and after the stent was implanted.
Researchers found the risk of restenosis was reduced by 64 percent simply by expanding a tiny balloon after the stent was placed in the diseased artery rather than before it was implanted. However, the group that underwent angioplasty after the stent had a larger number of strokes compared to the group who received angioplasty only prior to the stent, but that number was not statistically significant.
Results of the CREST trial also showed historically the lowest incidence of stroke as a complication of stenting and balloon angioplasty, regardless of the order. “We actually had too few complications to make any statistically significant assessment about risk of stroke between the different ballooning methods,” explained Dr. Malas.
An estimated 83.6 million adults in the U.S., about one in three, currently have some form of cardiovascular disease. An estimated 6.8 Americans are expected to suffer from stroke this year alone, according to 2013 statistics from the American Heart Association.
Balloon angioplasty is a common treatment for atherosclerosis, a hardening or narrowing of major arteries throughout the body. The carotid arteries are the main arteries supplying oxygen- and nutrient-rich blood to the brain directly from the aorta as it ascends from the heart. If these essential arteries become blocked, or stenotic, there is a higher risk of stroke because of small debris breaking off from the diseased artery and traveling to the brain. Angioplasty and stenting is performed by interventional cardiologists and vascular surgeons and involves guiding tiny instruments with medical imaging through a small incision in the groin area through major blood vessels to the affected artery—in this case the carotid arteries in the neck. Once in position, a small mesh coil called a stent is implanted inside the artery.
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