Carotid controversy: Medication alone may not eliminate stroke risk

RISK FACTOR PROFILE AND ANATOMIC FEATURES OF PREVIOUSLY ASYMPTOMATIC PATIENTS PRESENTING WITH CAROTID-RELATED STROKE. Journal of Vascular Surgery, November 2018

CHICAGO, Illinois, Oct. 20, 2018 – Recent advances in statins and other medications have led some researchers to suggest that surgical treatments for carotid stenosis should be limited to symptomatic patients – primarily those who have already had a stroke or TIA. However, a new study published in the Journal of Vascular Surgery questions whether medical therapy is a sufficient stroke-reduction strategy.

In the study, only 35 percent of stroke patients were receiving both statin and antiplatelet agents prior to their event, suggesting that asymptomatic carotid disease is unrecognized in many individuals, noted lead researcher Dr. W. Darrin Clouse of Massachusetts General Hospital.

“And the first manifestation of their disease,” he wrote, “could be the occurrence of a stroke.”

Stroke is the second most common cause of death and third most common cause of disability world-wide. Carotid revascularization, either by endarterectomy or stent, has a proven track record in preventing stroke in both asymptomatic and symptomatic patients with significant carotid disease.

Direct comparison between modern antiplatelet/statin regimens and carotid revascularization is ongoing in the CREST-2 Trial, but these results are years away from confirmation.

As reported in the November edition of the Journal of Vascular Surgery, researchers from the Massachusetts General Hospital led by Dr. W. Darrin Clouse and first author Dr. Derek Klarin assessed the atherosclerotic risk factor profiles, anatomic features, and clinical outcomes of previously asymptomatic patients admitted after a carotid-related stroke. Records from 3,381 patients admitted with an ischemic stroke between 2005 and 2015 were reviewed, revealing 219 patients (7%) were due to carotid disease.

Demographics of those with strokes secondary to carotid disease included:
• 61% white race
• 66% male gender
• Mean age 68 +/- 12 years
• Hypertensive 79%
• Tobacco abuse, 33% current, 29% former

Medical therapy noted upon admission involved:
• 50% antiplatelet therapy
• 55% lipid lowering agents
• 35% receiving both

Carotid disease in these stroke patients was noted to be:
• 43% with total occlusion
• 47% with high-grade stenosis (>70%)
• 10% with moderate stenosis (>50-70%)

Seventy-one percent of patients were determined to have had a moderate-severe stroke. Those receiving both antiplatelet and statin therapy were less likely to have this degree of stroke (44% versus 78%).

“Nearly one half of the patients we identified presented with complete internal carotid occlusion at time of their first symptoms, largely making them ineligible for stroke-risk reduction with CEA or stenting,” notes Dr. Clouse. “The effect of this inability to salvage carotid perfusion in patients with occlusion should be included in the assessment of risks and benefits associated with asymptomatic carotid revascularization.”

Dr. Clouse adds, “Taken together, these data suggest that medical therapy alone is unlikely to completely extinguish stroke risk in patients with significant carotid bifurcation atherosclerotic stenosis. The proper identification of stenosis, medical therapy institution, proper surveillance for progression, and revascularization are all important in minimizing progression to carotid-related stroke.”

The authors also note that of the stroke patients, only 7% had been screened, but 35% had been receiving both statin and antiplatelet agents, suggesting that some atherosclerotic disease had been detected.

While advances have been made in the medical treatment of carotid atherosclerosis, this important analysis of stroke patients argues strongly for the continued role of revascularization pending the results of the CREST-2 Trial.

This article will be freely available from October 15 to December 31: vsweb.org/StrokeStenosis.