Point/Counterpoint

Dr. Stephen F. Stanziale and Dr. Frank J. Criado with an Added Point by Dr. Magruder C. Donaldson

Stent Older Patients With Care

The decision to place a carotid stent in a patient aged 80 years or older must be made cautiously, based on evidence that the outcomes of these patients are substantially worse than outcomes in younger patients.

Although randomized trial results are not available, we reviewed the outcomes of 382 patients who received carotid stents during June 1996 and March 2004 at the University of Pittsburgh. About twice as many octogenarians died or had a stroke or myocardial infarction during the year after placement of a carotid stent compared with younger patients. During the first 30 days, there were nearly three times as many major adverse events in older patients. Neither symptom status nor use of embolic protection affected this finding. Our series included patients who were entered into 1 of 10 different regulatory trials, but nearly a third were treated outside of a study.

A variety of stent brands were used. Cerebral protection devices were used routinely starting in 2000; overall, protection devices were used in 62% of the older patients and in 52% of younger patients. The prevalence of asymptomatic carotid artery stenosis was 71% in patients aged 80 or older and 74% in patients younger than 80.

During the first 30 days after the procedure, the incidence of death, stroke, or myocardial infarction was 9.2% in the octogenarian patients and 3.4% in younger patients, a statistically significant difference.

One year post procedure, the combined rate for major adverse events was 25% among patients aged 80 or older, compared with 13% among younger patients, a statistically significant difference (J. Vasc. Surg. 2006;43:297-304). Only 56% of patients were available for follow-up after 1 year. In a multivariate analysis that assessed 26 variables, the only factors significantly associated with major adverse events at 30 days after treatment was octogenarian status, which raised risk almost threefold, and preprocedural treatment with aspirin, which cut risk by 77%.

Results from eight nonrandomized studies that were reported in 1998-2004 showed that carotid endarterectomy is roughly as safe in octogenarian as in younger patients, but this issue had never been studied in a randomized, controlled trial.

Questions about the safety of carotid stenting in the elderly became more pressing with the results from the lead-in phase of the Carotid Revascularization Endarterectomy Versus Stent Trial (CREST), which in 2004 showed that in 749 patients, the rate of death or stroke at 30-day follow-up was nearly threefold higher in older patients compared with those younger than 80.

Future results from randomized studies will determine whether carotid stenting, endarterectomy, or medical management is the best option for patients aged 80 or older.

Reconsider the Medical Options

Increasingly, questions are being raised about the appropriateness of carotid artery stenting in patients aged 80 years or older who do not have symptoms of carotid artery disease.

The recent advances that have been made in the medical management of carotid disease as well as an increased awareness of the dangers of stenting in elderly patients is leading to a paradigm shift in the way in which asymptomatic carotid disease is managed in octogenarians.

Medical management has now become better than ever, with drugs such as clopidogrel (Plavix) and statins joining aspirin as the cornerstones of therapy. Patients also can benefit from the many other drugs that are available today used for treating hyperlipidemia or hypertension.

And endarterectomy is still a viable option for selected patients. In fact, there is a growing realization that surgery in fact may be a safer alternative than stenting for asymptomatic patients who are aged 80 or older.

Asymptomatic patients who are at low risk for a poor outcome from carotid stenting remain good candidates for the procedure. But recent experience has shown that those higher-risk patients who are refused surgery because of their increased risk have fared no better when they are instead treated with carotid stenting.

Additional evidence documenting the poor outcome of octogenarians comes from the Carotid Acculink/Accunet Postapproval Trial to Uncover Rare Events (CAPTURE), a postmarketing approval study sponsored by Guidant. Results from this study were recently reported by Dr. Jay S. Yadav of the Cleveland Clinic.

About 25% of the 1,603 patients studied in CAPTURE were aged 80 years or older.

Among the 1,224 patients younger than 80 years in the study, the rate of death, stroke, or myocardial infarction during the first 30 days after carotid stenting was 4.3%, compared with a 7.7% rate among the 378 patients aged 80 or older. This was a statistically significant difference.

Among the 1,446 (90%) patients in the study who were asymptomatic, the rate of death, stroke, or myocardial infarction was 3.5% among the 1,116 patients who were aged younger than 80, and 6.4% among the 330 patients who were octogenarians. This difference also was statistically significant.

Death, stroke, and myocardial infarction are not the only bad outcomes that can occur in the elderly.

Octogenarians also seem especially vulnerable to neurologic deficits that occur secondary to carotid stenting, even when an embolic filter is used.

Microemboli that are too small to be caught by the distal filter flow from the carotid into the brain during stenting and may cause neurologic deficits, although this effect has not been measured in major studies.

This may be why surgery is safer for these patients; endarterectomy does not seem to produce microemboli.

An Added Point

The two opinions that are expressed in this “Point/Counterpoint” largely agree on recent data suggesting increased short and mid-term morbidity among octogenarians who undergo carotid stenting, even using the most modern protection devices.

This cautionary information should result in raising our threshold for intervention among the elderly, particularly if asymptomatic, relying on surveillance while pursuing enhanced medical management as suggested by Dr. Criado.

Dr. Stanziale’s data again emphasize the importance of preoperative aspirin for patients in whom intervention is judged worth the risk. Further study is needed to elucidate the underlying factors which make carotid stenting more hazardous among the aged-whether increased calcification, tandem lesions, tortuosity, challenging aortic arch anatomy, reduced neurologic reserve in the face of procedural atheroemboli or other issues-thereby allowing more precise selection of good risk patients for intervention.

Dr. Magruder C. Donaldson is an Associate professor of surgery at Harvard Medical School, and chair of the department of surgery at MetroWest Medical Center, Framingham, Mass.