Michael D. Shapiro, D.O.
Dr. Shapiro is director of OHSU’s Atherosclerosis Imaging program. He is board certified in Cardiovascular Medicine, Cardiovascular CT and Clinical Lipidology. His primary focus is genetic and acquired disorders of cholesterol and triglycerides, and cardiovascular risk assessment in apparently healthy individuals.
Affordable CIMT available to identify vascular risk
If you definitively knew that your otherwise healthy 40-year-old patient had early signs of atherosclerosis, how would you treat that patient differently? In assessing cardiovascular risk, physicians can often clearly identify the low- and high-risk patients by conventional risk algorithms, but the many people that fall in the intermediate-risk category can benefit from additional diagnostic testing to screen for early atherosclerosis. Measurement of carotid intima-media thickness (CIMT) can provide reliable information about an individual’s risk of a major cardiovascular event in the next 5-15 years.
CIMT is not new technology, but it is underutilized. This is because health insurance providers typically exclude it from covered benefits, and it can cost hundreds of dollars as an out-of-pocket expense. To make this valuable tool more widely accessible and accurate, OHSU is now offering a self-pay ultrasound measurement of CIMT for $99 at our Center for Health and Healing in Portland.
Valuable information from CIMT screening
Utilizing ultrasound technology to image the carotid arteries, CIMT is a noninvasive method for early diagnosis of subclinical atherosclerosis. CIMT provides a measurement of the thickness of the arteries’ inner layers, a surrogate for atherosclerosis, and assesses for the presence of plaque. The screening measures several areas of the carotids and provides an average measurement. Clinicians can use this information to assess an individual’s risk and initiate lifestyle changes or medical therapy to prevent, halt or reverse the disease process. And because there is no exposure to ionizing radiation, clinicians and patients can elect to re-test to measure the effectiveness of interventions.
CIMT only as good as the expertise
CIMT is an operator-dependent test which requires skilled technicians to administer it or the measurements will produce meaningless results. To ensure accuracy, OHSU employs highly trained technicians using state-of-the-art equipment, and an experienced vascular surgeon reads the results.
CIMT versus carotid duplex
Though both tests use ultrasound technology, CIMT serves a different purpose than carotid duplex (or carotid Doppler). We ask for a carotid duplex for patients presenting with symptoms of a transient ischemic attack or stroke to look for a critical blockage. Conversely, we only request CIMT for an asymptomatic patient to assess for future risk of heart attack or stroke.
CIMT versus coronary artery calcium scoring
Both tests are valuable and predictive screenings of cardiovascular risk, but they are useful in different populations. Because there is no radiation with CIMT, there is no age limitation, allowing us to screen younger people. We can also reassess CIMT to monitor effect of therapeutic interventions. Coronary artery calcium scoring is CT-based, involving a low dose of radiation. It is generally a one-time assessment given to people of middle-age or older to establish individual risk.
When to consult or refer
- Asymptomatic adult patients who have at least one risk factor for cardiovascular disease.
- Family history of heart attack or stroke, especially at a young age.
- Younger individuals with inherited dyslipidemias, i.e., familial hypercholesterolemia or elevated Lp(a) levels.
- Current or former smokers.
- Patients with HIV disease.
At the OHSU Center for Preventive Cardiology, we offer a comprehensive screening program. If you have questions about CIMT, contact Dr. Michael Shapiro at firstname.lastname@example.org. For other questions, please call the OHSU Physician Advice and Referral Service at 503-494-4567. To refer a patient, please fax to 503-346-6854.Back to articles