AIM: With carotid stenting, less should be more for asymptomatic patients
The FDA’s decision to expand coronary artery stenting (CAS) indications to include patients both at high risk and standard risk of stroke has increased the use of CAS to treat carotid stenosis. An editorial published Nov. 14 in Archives of Internal Medicine questioned the increased use of CAS, particularly due to the rather inconclusive data, and concluded that CAS should get a “less is more” designation for asymptomatic patients because of the “definite harms and unclear benefits.”

CAS procedures have seen an uptick since 1998 when only 0.1 per 1,000 Medicare beneficiaries per year received CAS. In 2007, this number increased to 0.6 procedures per 1,000 beneficiaries per year. Meanwhile, beginning in October 2004, the rate of CAS procedures quadrupled and between 2004 and 2006, the number of CAS procedures increased from an average of 266 per month to 1,015 per month, suggesting that CAS may now be a substitute for CEA, Seth A. Berkowitz, MD, and Rita F. Redberg, MD, MSc, both of the department of medicine at the University of California, San Francisco, wrote.

Berkowitz and Redberg noted that an estimated 70 to 90 percent of CAS procedures are being performed in asymptomatic patients. “We believe the increase in carotid stenting procedures at the expense of CEA, as well as the number of asymptomatic patients treated, to be concerning for several reasons,” the authors wrote. “The superiority of carotid stenting over CEA is far from proven, even among symptomatic patients.”

The authors noted that data emerging from the major stenting trials such as CREST, ICSS and SPACE, showed that CAS compared with CEA increased the risk of stroke. A meta-analysis of CREST and ICSS found that CAS was associated with a significant increase in the risk of stroke and mortality and did not have statistically significantly reductions in the risk of periprocedural MI.

“In addition, the increase in strokes is particularly concerning, given stroke's significant detrimental effect on quality of life, which is often far more devastating than periprocedural MI,” the authors wrote.

Additionally, caution must be used when treating elderly patients (over the age of 70) due to the higher risk of stroke they face. This patient population fared better with CEA, and the risk of events in these patients treated with CAS was double that for CEA-treated patients, they reported. Women also did worse with CAS compared with CEA.

“As concerning as the findings in women and older patients are, the increase in use among asymptomatic patients may be even more troubling,” Berkowitz and Redberg wrote. “As with other interventional vascular procedures, the balance of benefits and burdens to the patient depends heavily on the risk of the outcome being prevented.”

Because asymptomatic patients have less of a risk for events, they have less to gain from a CAS procedure, the authors noted. The authors also noted that real-world CAS data showed that 30-day mortality rates after CAS in older patients to be almost 2 percent, twice the number seen in clinical trial results.

“[C]ardiologists are performing procedures on patients who are less likely to have a history of neurological conditions, such as acute stroke or TIAs [transient ischemic attacks], while more likely to have had a recent invasive cardiac procedure,” Berkowitz and Redburg wrote. “These data suggest that cardiologists are actively screening their patients with coronary disease for carotid stenosis and performing carotid stenting when such disease is identified, regardless of a history of neurologic disease or symptoms.”

No trial has yet to compare aggressive medical therapy with carotid stenting, making the benefits for asymptomatic patient populations from CAS unknown.

“[C]arotid stenting for asymptomatic persons with carotid stenosis, as well as for all persons older than 70 years and all women, gets a 'less Is more' designation because it has definite harms but unclear benefits,” the authors summed, unless a clinical trial proves otherwise.