A combination of angioplasty and stenting are as good as the gold standard of surgery for clearing fat deposits from neck arteries and keeping them open, researchers reported Wednesday. The findings in the NIH-funded trial, which included more than 2,500 patients, contradict the findings from smaller European trials which concluded that stenting is riskier.
The results, reported at a meeting in February and published in the New England Journal of Medicine on Wednesday, show that the two procedures are virtually equivalent, but that patients who undergo stenting tend to have more strokes in the months after the procedure, while those who undergo surgery tend to have more heart attacks. "Which complication would you prefer?" asked Dr. Christopher White of the Ochsner Heart & Vascular Institute in New Orleans, a spokesman for the Society for Cardiovascular Angiography and Interventions. "The answer is, I don't want either one." As a cardiologist, he wants to match one procedure or the other to the patient to minimize complications. "That's why I, as a clinician, need freedom to pick and choose, and I currently don't have that freedom" because Medicare and many insurance companies do not reimburse for stenting of the neck artery.
Experts hope the new results from the study known as CREST will convince Medicare to change its reimbursement policies. That change might also be helped along by new guidelines on choosing between the two surgeries to be issued this summer by SCAI and the Society for Surgery.
"We now have two safe and effective methods to treat carotid artery disease that can be targeted to individual patients," Dr. James Meschia, a neurologist at the Mayo Clinic in Jacksonville and one of the study's principal co-authors, said in a statement
An estimated 700,000 Americans suffer strokes each year, and the bulk of those incidents are caused by the buildup of plaque in the carotid arteries, the primary vessels in the neck that carry blood to the brain. The plaque can build up to the point where it completely blocks blood flow, or pieces can break off and lodge in smaller vessels in the brain.
The gold standard for treatment of the condition is surgery to scrape the plaque out of the artery, a process called carotid endarterectomy. About 150,000 of the procedures are performed in the United States each year. A newer procedure is to insert a catheter through the groin and thread it to the neck, where a balloon is inflated to compress the plaque and a wire mesh spring called a stent is inserted to prevent the plaque from re-expanding. They are less invasive, require a shorter hospital stay and are cheaper, but some have questioned their safety.
The CREST (Carotid Revascularization Endarterectomy vs. Stenting Trial) study, led by Dr. Thomas G. Brott of the Mayo Clinic, enrolled 2,502 patients at 117 centers in the United States and Canada between 2000 and 2008. They were randomly assigned to undergo either surgery or stenting. The study was conducted in large and small, public and private hospitals. "The idea was to design a study that reflects the U.S. experience," he said in a statement.
The chief difference between the U.S. and European studies, White said, is that those who performed the stenting procedure in this country were required to demonstrate proficiency with the technique before the trial began, while those who performed it in Europe were "novices" who had just been taught the technique. "Which is ridiculous," he said. "How can you compare procedures when you are teaching how to do one and have an expert on the other side?" White, it should be noted, is a stenter.
Overall, 4.1% of patients in the stenting group had strokes in the weeks after the procedure, compared with 2.3% of those who had surgery. But 2.3% of those in the surgical group had heart attacks, compared with 1.1% of those with stents. The results were similar whether or not the patients had displayed symptoms before the operation.
The higher incidence of strokes for stenting is misleading, White said. "Not all strokes are the same. For big, damaging strokes, there was no difference between surgery and stenting. The difference was in minor strokes," from which patients generally recover with no significant problems.
The results do provide some general guidelines for how to choose between the two approaches. Patients in CREST who were over 70 tended to do better with surgery, perhaps because their arteries are less flexible. Those under 70 did better with stenting. People with cardiovascular disease are likely to do better with stenting, but those with hardened or "twisty" arteries are more likely to do better with surgery.
"Local experience is also important," White said. "If you don't have someone who is an expert at stenting, I would favor surgery. Procedures tend to be things that are learned, developed and in which people develop expertise.... I would prefer not to be treated by a beginner."
Abbott Laboratories, whose stents were used in the study, said it would use the data to apply to the Food and Drug Administration to market the stents to most patients with problematic carotid arteries. The stents are now approved only for use in patients who are at high risk from surgery due to anatomical factors, age or other considerations.
-- Thomas H. Maugh II