“Ultra” in everyday life means beyond what is usual or ordinary. Ultrasound refers to sound beyond the upper limit of human hearing.
Sonar or sound waves have been used in obstetric medicine for many decades as a noninvasive diagnostic tool that shows the development of the fetus. As nearly every pregnant woman knows, such scans can produce some of the most memorable moments in a parent’s life.
Far less well-known is a relatively new medical application known as intravascular ultrasound (IVUS), a highly specialized technology in use for a decade or so that is becoming increasingly important as the incidence of cardiovascular disease increases.
With clogged arteries literally being death traps, IVUS has evolved along with stents and catheters as both a screening tool and a novel method for improving stenting procedures to rid key arteries of harmful plaque.
In its most advanced form, color-coded IVUS can identify different constituents of plaque found in diseased arteries and actually see inside an artery, whereas the traditional angiogram - an X-ray photo of vessels following an injection of dye - only provides images outside the heart.
“An angiogram underestimates the burden of the disease,” says Dr. Matthews Chacko, assistant professor and director of peripheral interventions at the Johns Hopkins School of Medicine’s Heart and Vascular Institute.
Using ultrasound as a detection tool for cardiovascular problems has expanded in recent years alongside the more highly technical application of the IVUS. It’s done, Dr. Chacko explains, by putting the tool on a catheter advanced over a guide wire “to give a real-time view. Different measurements can be made. It helps identify vulnerable plaque - one that might be prone to rupture. Some statin manufacturers are using the technique to see about the changing characteristics of plaque after administering the statin medicine.”
“Cardiovascular disease is now the No. 1 killer,” he notes. “Vascular disease in the neck causes stroke, and in the legs it can lead to limb loss.”
Testing for clogged leg arteries is a relatively simple matter. As noted in the September issue of Consumer Reports, it involves having a doctor check the pulses at the top of each foot and inside each ankle; if these aren’t strong, a blood-pressure cuff should be applied to the ankle to see that - ideally - it is in line with the pressure in the arm. The tests measure important peripheral arteries that often reflect what is happening in arteries leading to the heart and brain.
“Probably 10 million people in this country have blockages in their legs,” Dr. Chacko says. “The majority won’t go on to a problem, but they are at a much higher risk of having a heart attack or stroke.”
Vascular disease, the Society for Vascular Surgery notes in a published statement, “is generally asymptomatic until a catastrophic event occurs, such as a stroke or aneurysm rupture.” That is why the society recommends a preventive screening by noninvasive ultrasound for anyone 55 or older with cardiovascular risk factors, such as a history of hypertension, diabetes mellitus or smoking.
Even people with no known symptoms or risk factors can benefit, as Carlton Holmes, 64, of Fairfax, discovered 1 1/2 years ago when he elected to pay $100 to a mobile Life Line Screen team, the largest single employer of ultrasound technicians in the country, to check his cardiovascular health.
He had seen ads for the 15-year-old Cleveland-based company and talked it over with his wife.
“One hundred dollars,” he says. “We blow that in a weekend.”
He signed up for five tests done shortly thereafter at a local site. Results that came in written form two weeks later said he should go to his doctor to have his carotid arteries checked.
“I felt fine. I didn’t have any symptoms,” he says, “but the doctor said, ‘I need to have you go to a local clinic for testing.’”
The second opinion confirmed the diagnosis from a Life Line physician, who, company spokeswoman Joelle Reizes said, reviews and signs off on all reports.
It was determined that Mr. Holmes had a blockage in his right carotid artery. An exploratory outpatient procedure under local anesthetic followed. “The doc said, ‘If I find bad stuff, do you want me to fix it?’ I said, ‘Please fix it.’ It’s like a car job; you don’t want to have to bring the car back in again and pay twice.”
There was a 90 percent blockage.
“I was a prime candidate for a stroke,” he says. “So they put in a stent right away.”
He now is on blood thinners and other aids he calls “senior citizen medication.”
A self-described “big fellow of 6-foot-2 and 260 pounds,” he is retired but works part time driving a Fastran specialized transportation bus. “I didn’t believe in [the screening method] at first, but I found it saved my life,” he says.
His wife, who is 12 years younger, since has had the screening exam, and no complications were found.
“The main qualification is age,” Ms. Reizes says. It’s generally for anyone over 50 - “but sometimes doctors refer people in their 40s. This is targeted use of a proven technology, as opposed to full-body scanning. The key here is the use of ultrasound, which is safe.”
More than 5 million people have been tested by this commercial service to date, essentially for three leading causes of stroke, arteriofibrilation and systolic hypertension. The company also does peripheral screening, measuring arms and legs.
“If we can identify a disease early, there are things you can do. Eighty percent of strokes can be prevented,” Ms. Reizes says.
About 8 percent of people have been found to have a disease of some kind - “some signs of atherosclerosis,” she says.