Aug. 28, 2009 -- Surgery is safer and slightly more effective than balloon angioplasty for preventing strokes, new research shows.
Two newly published investigations join a growing body of research showing worse outcomes in patients who have balloon angioplasty to clear the clogged neck arteries that supply oxygen-rich blood to the brain.
The findings could have a big impact on clinical practice, especially in the United States where balloon angioplasty is now performed far more often than surgery to open blocked or narrowed carotid arteries.
Both procedures carry their own risk of stroke, but it has not been clear if one was safer or worked better than the other.
“Taking all the studies together, the risk of stroke is now clearly higher with angioplasty,” stroke researcher Peter M. Rothwell, MD, PhD, tells WebMD. “What these two (new) papers now also show is that the long-term outcome is also worse with angioplasty. This is therefore a double-blow for angioplasty.”
Angioplasty Considered Safer
Narrowing of the carotid artery because of buildup of fatty plaque is one of the main risk factors of stroke.
The plaque can either be removed surgically or the narrowed artery can be opened by inflating a tiny balloon threaded up to the neck through a narrow catheter inserted into a groin artery. These days, a wire mesh stent is almost always inserted during angioplasty to keep the artery open.
Balloon angioplasty with stenting has become the procedure of choice in the U.S. in recent years, largely because it has been considered safer than surgery, says Larry B. Goldstein, MD, who directs Duke University Medical Center’s stroke center.
It is now clear that this is not the case, Goldstein tells WebMD.
The new studies, both performed by the same international research team, include the longest follow-up yet of patients treated with surgery or angioplasty for coronary artery disease.
Researchers followed 251 patients who had surgery and 253 who had angioplasty for up to 11 years, lead investigator Martin M. Brown, MD, tells WebMD.
Eight years later, slightly more angioplasty patients than surgery patients (11.3% vs. 8.6%) had experienced strokes, although the difference wasn't statistically significant.
The angioplasty group also had more minor strokes within the first 30 days of having the procedure, compared to the surgery group (eight vs. one). The surgery group had more cases of cranial nerve palsy (22 vs. zero), a temporary nerve injury, and hematoma that needed surgery or longer stay in the hospital (17 vs. three).
In the second study, the researchers used ultrasound imaging to look for plaque buildup in the carotid arteries of 213 patients following surgery and 200 following angioplasty.
After five years, three times as many angioplasty patients had severe artery blockage (31% vs. 10%). “Patients who had angioplasty with stents had a lower risk of plaque recurrence than those who had angioplasty alone.
“The trials make it clear that surgery is the best option, but it is important to understand that the difference is not that great,” lead investigator Martin M. Brown, MD, tells WebMD. “Patients who can’t have surgery or don’t want it are still likely to do well.”
Surgery, Angioplasty or No Treatment
Because recruitment for the trials occurred before stents were routinely used with angioplasty, the results are not all that relevant to patients who have the procedure today, Goldstein says.
“One criticism is that the procedures used then are somewhat outdated, but this is an issue with any long-term interventional study,” he says. “The technology tends to move faster than the sciences.”
Another pressing question is whether too many procedures to clear clogged carotid arteries are being performed in the United States, he says.
The benefits of treatment are well established for patients with symptoms associated with carotid artery disease, but this is not the case for patients who have no symptoms, Goldstein says.
“If you have symptomatic high-grade narrowing of the carotid arteries, the risk of stroke can be as high as 26% over two years with no intervention,” he says. “The stroke risk for someone with asymptomatic disease is on the order of 1% to 2%.”
He tells WebMD that in the U.S. the majority of angioplasty with stenting procedures for carotid artery disease are performed on asymptomatic patients.
“The question now is who, if anybody, with asymptomatic disease should have anything done to their carotid artery, because the risk of causing harm is not small,” he says.