Carotid Stenosis: Using Cerebrovascular Reserve To Assess Stroke Risk

Ankur Pandya, PhD Assistant Professor of Healthcare Policy and Research Departments of Healthcare Policy and Research Weill Cornell Medical College New York, NY Interview with:
Ankur Pandya, PhD
Assistant Professor of Healthcare Policy and Research
Departments of Healthcare Policy and Research
Weill Cornell Medical College
New York, NY 10065.

Medical Research: What are the main findings of the study?

Dr. Pandya: Asymptomatic carotid stenosis is a highly prevalent condition that can lead to ischemic stroke, which is a leading cause of death and healthcare costs in the U.S. Revascularization procedures are often performed on asymptomatic carotid stenosis patients, but experts have questioned whether the stroke prevention benefits outweigh the risks and costs of revascularization in these patients. Imaging-based stroke risk assessment has traditionally focused on the degree of artery narrowing, but there has been growing interest in using cerebrovascular reserve (CVR) assessment to stratify these patients into those that are more likely to have a stroke, and thus better candidates for revascularization, and those that would be better off with less invasive management strategies (such as medical therapy). We therefore developed a simulation model to evaluate whether the CVR-based decision rule could be used efficiently select the right patients for revascularization. We found that the CVR-based strategy represented the best value for money compared to immediate revascularizations or medical therapy-based treatment for all patients.

Medical Research: What was most surprising about the results?

Dr. Pandya: Interestingly, we found that there were combinations of certain variables (such as baseline stroke risk and risk of complications during revascularization) that led to the immediate revascularization or medical therapy-based strategies being optimal.

Medical Research: What should clinicians and patients take away from your report?

Dr. Pandya: (from the paper): “Assessment of CVR with transcranial Doppler ultrasound can allow identification of patients with carotid stenosis who are at higher baseline risk for stroke, and thus, are better candidates for revascularization procedures.

The optimal decision on performance of revascularization procedures in asymptomatic patients with carotid stenosis depends on baseline risk of stroke and the likelihood of procedure complications, factors that can vary according to patient, provider, and institution.”

Medical Research: What recommendations do you have for future research as a result of this study?

Dr. Pandya: We are currently using our simulation model to explore whether other imaging tests, like MRI, could be efficiently employed to look at the composition and stability of plaque which may give greater insight into those plaques most likely to rupture and cause symptoms.


“Carotid Artery Stenosis: Cost-effectiveness of Assessment of Cerebrovascular Reserve to Guide Treatment of Asymptomatic Patients.” Collaborating with Dr. Pandya at Weill Cornell Medical College were Ajay Gupta, M.D., Hooman Kamel, M.D., Babak B. Navi, M.D., Pina C. Sanelli, M.D., M.P.H., and Bruce R. Schackman, Ph.D.
Journal Radiology Sept 2014 Ahead of Print