Did you know that an ultrasound exam of your neck arteries is one of the best ways to check for atherosclerosis (plaque in the artery wall that can lead to a heart attack or stroke? As I discuss in this Fox Health News article, this FDA-approved screening, carotid intima media thickness (cIMT), can uncover hidden risk for these events in seemingly healthy people.
For example, when Wayne Williams consulted me four years ago, he had normal cholesterol and blood pressure, ate a healthy diet, and felt fine. Yet a 15-minute cIMT test showed that the then 48-year-old was at moderate-to-high risk for a heart attack or stroke in the next ten years. “I learned then that [atherosclerosis] was a silent killer,” he says.
This disease can be missed if medical providers only check traditional risk factors.
Nearly 75% of heart attacks occur in people with “normal” levels of LDL (bad) cholesterol, according to a study of 136,905 people. What’s more, 50% of the heart attack patients studied had “optimal” LDL levels.
Another scary fact: Nearly 70% of heart attacks strike people who have never been diagnosed with heart disease, highlighting the value of being screened for potentially lethal plaque, so it can be treated in time to prevent a heart attack or stroke. Had Wayne gone undiagnosed and untreated, there was an 83% risk that he would have suffered one of these events by age 58.
While an ultrasound of the neck may seem like a surprising way to tell if you might be headed for a heart attack or stroke, the carotid arteries, which lie just below the surface of the skin on each side of your neck, offer an easily accessible “window” to blood-vessel health, without exposure to X-rays. CIMT measures the thickness of the two inner layers–called the intima and the media–of these arteries.
Most important, this screening can detect atherosclerosis lurking in the artery wall, which we call “the cat in the gutter.” As Dr. Bradley Bale and I report in our book, Beat the Heart Attack Gene, these deposits are like a hidden predator waiting to pounce on its unsuspecting prey — by leaping out and causing a heart attack or stroke. CIMT can also be used to find out how “old” your arteries are, compared to your chronological age. Having arteries that are eight or more years “older” than you are signals future risk for coronary heart disease (CHD), while finding plaque means you already have it.
A recent study of more than 10,000 people found that adding intima-media thickness and the presence of plaque to traditional risk factors dramatically boosted the accuracy of 10-year predictions of heart attack and stroke risk. In fact, 22% of the patients were reclassified as being at higher or lower risk when cIMT and plaque were taken into account. The study compared initial predictions with the patients’ actual rate of cardiovascular events over a decade.
Who should be screened with cIMT? I served on the Society of Atherosclerosis Imaging and Prevention’s expert committee that developed these recommendations for appropriate use of cIMT:
- Screening patients whose 10-year risk for CHD is moderate (6 to 20%)
- Screening patients ages 30 or older with metabolic syndrome
- Screening patients with diabetes or a family history of early CHD
- Screening people with two or more of these risk factors: low HDL (good) cholesterol or high LDL, diabetes, age (being over 45 for a man or over 55 for a woman), and a family history of CHD.
If cIMT reveals plaque, as happened with Wayne, treatment may include lifestyle changes, medication and supplements. Today, the plaque in Wayne’s arteries is completely stabilized and calcified. That means the “cat” has been captured and caged, enabling Wayne to live well without fear of a heart attack or stroke.