Atheroslcerosis Screening

What is atherosclerosis?
Atherosclerosis — hardening and narrowing of the arteries — gets a lot of bad press, with good reason. This progressive process silently and slowly blocks arteries, putting blood flow at risk.
Atherosclerosis is the usual cause of heart attacks, strokes, and peripheral vascular disease — what together are called “cardiovascular disease.” Cardiovascular disease is the No. 1 killer in America, with more than 900,000 deaths last year.

Why should I get screened for it?
If you are 40 and generally healthy, you have about a 50% chance of developing serious atherosclerosis in your lifetime. The risk goes up as you get older. The majority of adults older than 60 have some atherosclerosis but often do not have noticeable symptoms.

What are the screening tests for atherosclerosis?
At Canada Diagnostic Centres, we offer three evidence-based (meaning that there has been rigorous scientific testing and validation of these tests using long-term randomized trials).

Coronary Calcium Score
Screening for early signs of atherosclerosis
Age 40+ males
Age 50+ females
1 mSv of radiation (equivalent to about 9 months Vancouver background radiation)

The Coronary calcium-score screening heart scan is a test used to detect calcium deposits found in atherosclerotic plaque in the coronary arteries. State-of-the-art computerized tomography methods, such as this one, are the most effective way to detect early coronary calcification from atherosclerosis, before symptoms develop. The amount of coronary calcium has been recognized as a powerful independent predictor of future cardiac events and may be used to guide lifestyle modifications and preventive medical therapies to reduce this risk.

Your doctor uses the calcium-score screening heart scan to evaluate risk for future coronary artery disease. If calcium is present, the computer will create a calcium “score” that estimates the extent of coronary artery disease based on the number and density of calcified coronary plaques in the coronary arteries.

Long-Term Prognosis Associated With Coronary Calcification Observations from a Registry of 25,253 Patients
Matthew J. Budoff, MD,* Leslee J. Shaw, PHD,† Sandy T. Liu,* Steven R. Weinstein,*
Tristen P. Mosler, Philip H. Tseng,* Ferdinand R. Flores,* Tracy Q. Callister, MD,‡
Paolo Raggi, MD,§ Daniel S. Berman, MD† Torrance and Los Angeles, California; Nashville, Tennessee; and Atlanta, Georgia “This large observational data series shows that CAC provides independent incremental information in addition to traditional risk factors in the prediction of all-cause mortality”. (J Am Coll Cardiol 2007;49:1860-70) © 2007 by the American College of Cardiology Foundation
Carotid Artery – CIMT
Screening for plaque in the carotid arteries, plus measuring the thickness of the carotid artery walls
Ages 50+
Ultrasound – No radiation

The American Heart Association Prevention Conference V recommends CIMT for patients who are older than 45 years and require further clarification of their cardiovascular risk.

Tests for subclinical atherosclerosis such as CIMT will help clinicians to more effectively identify the vulnerable patient who would benefit from aggressive prevention intervention. (J Am Soc Echocardiogr 2007; 20:907914)

Use of Carotid Ultrasound to Identify Subclinical Vascular Disease and Evaluate Cardiovascular Disease Risk: A Consensus Statement from the American Society of Echocardiography Carotid Intima-Media Thickness Task Force Endorsed by the Society for Vascular Medicine James H. Stein, MD, FASE, Claudia E. Korcarz, DVM, RDCS, FASE, R. Todd Hurst, MD,
Eva Lonn MD, MSc, FASE, Christopher B. Kendall, BS, RDCS, Emile R. Mohler, MD,
Samer S. Najjar, MD, Christopher M. Rembold, MD, and Wendy S. Post, MD, MS, Madison, Wisconsin; Scottsdale, Arizona; Hamilton, Ontario, Canada; Philadelphia, Pennsylvania; Baltimore, Maryland; and Charlottesville, Virginia

“The ability of CIMT to predict future CVD events was independent of traditional risk factors. Furthermore, 9 large studies have demonstrated similar or greater predictive power for carotid plaque and CVD. Measuring CIMT and identifying carotid plaque can be useful for refining CVD risk assessment in patients at intermediate CVD risk”

Abdominal Aortic Aneurysm (AAA) Screening
Screening for AAA’s – Ages 50+ males and females
Ultrasound – no radiation

Abdominal aortic aneurysm (AAA) occurs in 5% of men and 1% of women over the age of 65. AAA rupture is fatal in 80%-90% of cases. 10th leading cause of death in white men 65 to 74. Most AAAs are asymptomatic, and physical examination lacks sensitivity for detecting an aneurysm.

The Canadian Society for Vascular Surgery recommends:

  1. National and provincial health ministries develop a comprehensive population-based ultrasound screening program for AAA detection
  2. All men aged age 65-75 be screened for AAA
  3. women over age 65 at high risk secondary to smoking, cerebrovascular disease and family history
  4. men less than 65 with positive family history