Philadelphia, PA - A new study shows an increased risk for death or postoperative stroke of about 38% among patients undergoing combined coronary artery bypass grafting (CABG) and carotid endarterectomy (CEA) vs CABG alone [1].

"The benefit of this combined procedure is controversial," said study author Dr Richard M Dubinsky (University of Kansas Medical Center, Kansas City) in a statement from the American Academy of Neurology (AAN). "Given this significant increase in postoperative stroke and death, a randomized clinical trial of the combined surgery is needed to determine the benefit, if any, compared with performing the operations in separate hospitalizations."

A separate report suggests a reduction over time in the number of carotid endarterectomy procedures thought to be done for inappropriate reasons [2]. The authors, led by Dr Ethan A Halm (Mount Sinai School of Medicine, New York) credit results of the landmark randomized endarterectomy trials for this improvement but express concern about an observed increase in CEA in asymptomatic patients, where, they note, the net benefit from surgery is low.

Both studies are published in the January 16, 2007 issue of Neurology.

In the first report, Dubinsky and colleagues used data from the Nationwide Inpatient Sample, representing a stratified sample of 20% of all US acute hospital admissions, to compare the rates of hospital mortality and postoperative stroke in patients undergoing combined CEA and CABG vs those rates with CABG alone.

The hope with the combined procedure is to protect the carotid circulation from artery-to-artery embolic stroke during CABG and to lessen the risk by having just one operation with a single exposure to anesthesia, even though the combined operation is longer, the authors note.

In this analysis, they found that the proportion of CABG procedures combined with CEA grew over the study period of interest, from 1.1% in 1993 to 1.58% in 2002. After adjustment for comorbidities, patients who received both procedures had a 38% increased risk for the combined outcomes of death and postoperative stroke compared with CABG alone.

There was some suggestion that being female conferred a protective effect in terms of outcome, among the first times this has been seen, they point out.

"The frequency of combined CEA-CABG has increased, but the reported case series are inadequate to conclude whether there is a benefit to combining the procedures," the authors conclude. "A randomized controlled clinical trial, stratified for the degree of carotid stenosis and for previous stroke, with a follow-up of at least one year, is clearly needed to determine the benefit, if any, of combined CEA-CABG in patients with carotid and coronary atherosclerosis."

In an accompanying editorial, Drs Thomas E Feasby (University of Alberta, Edmonton) and Henry JM Barnett (Robarts Research Institute, London, ON) write that this additional risk is lower than has been reported in some other recent studies but "still suggests caution in combining these two procedures for what is usually asymptomatic carotid stenosis.

"Given the frequency of the combined procedures (1.58% of all [CEAs] in 2002), this is a situation suitable for cautious use in the hands of experienced experts until it is proven efficacious in a randomized controlled trial," they conclude.

In their separate report, Halm and colleagues assessed how appropriateness and indications for CEA have changed since publication of the major CEA trials during the late 1990s, including the North American Symptomatic Carotid Endarterectomy Trial (NASCET) and the Asymptomatic Carotid Atherosclerosis Study (ACAS).

Those trials were launched in response to the RAND Health Service Utilization Study in 1981, suggesting that 32% of CEA procedures performed in Medicare beneficiaries were done for inappropriate indications. The current study, the New York Carotid Artery Surgery (NYCAS) study, assessed appropriateness in 9588 CEA procedures done between January 1998 and June 1999 among elderly patients in New York State.

Detailed data were abstracted from medical records and compared with a list of 1557 indications for CEA. The authors report that the vast majority of the procedures were done for reasons deemed appropriate; only 8.6% were thought to be inappropriate, down significantly from 32% in the first RAND study.

The most common reasons that surgery was deemed inappropriate were high comorbidity in asymptomatic patients; operating after a major stroke; or for only minimal stenosis.

Nearly three quarters of patients, 72.3%, underwent CEA for asymptomatic stenosis, while 18.6% had had a TIA and 9.1% a stroke.

"The good news is following the large public investment in medical research on who should undergo carotid endarterectomy, there's been a large reduction in the number of patients undergoing the procedure for inappropriate reasons," Halm said in a statement from the AAN. "The bad news is there's been a shift toward operating predominantly on patients with no symptoms from the blocked arteries, where the benefit from surgery is lower and is reduced further for patients with other medical conditions."

In the same editorial, Feasby and Barnett also express concern about the high use of the procedure in asymptomatic patients. Although ACAS showed a benefit from surgery in patients with high-grade stenosis, the absolute risk reduction in that study was based on the ACAS group's perioperative stroke rate of only 2.3%, they point out.

This makes the ACAS result a "best-case scenario," because the complication rate in the study by Halm et al was 3% and in another recent report in 10 US states was 4.5%—a level at which patients would have been more likely to survive without stroke if they received medical, not surgical, intervention.

"Consequently, while the results of the Halm et al study that the appropriateness of [CEA] seems to have improved markedly compared with the 1980s is gratifying, the trend toward operating on predominantly asymptomatic cases is concerning," they conclude.