In February we focus on heart health with Valentine's Day and Go Red for Women campaigns. After 25 years of practicing interventional cardiology, I remain puzzled by a dilemma. At age 50 we screen for colon cancer by looking at the colon directly through a scope, breast cancer by imaging the breasts, prostate cancer by palpating it, and gynecological cancers by internal inspection. For heart disease, the No. 1 killer in the Western world, we perform a history and physical, perhaps an EKG, and some lab work. How can we compare these indirect heart assessments, far removed from examining the actual arteries, to the methods of detecting these other pathologies?
Let's review a few facts well known to cardiologists but likely secrets to the lay public. For years, the concept of an executive physical stress test has been promoted. In reality, it hasn't been promoted or recommended by the American College of Cardiology. In fact, the American College of Cardiology recommends against stress testing in asymptomatic persons without known heart disease (http://circ.ahajournals.org/content/106/14/1883.full). Why? The answer is that there are so many inaccurate predictions coming from stress testing in asymptomatic people that they produce confusion, a huge amount of anxiety, and potentially harmful and unnecessary procedures.
How can this be? Studies show that if your heart arteries are narrowed at least 70 percent or more by coronary artery disease, the chances are about 70 percent that a routine exercise treadmill stress test will show an abnormality that identifies silent heart disease (http://www.ncbi.nlm.nih.gov/pubmed/22512607). That means that 30 percent of the time, an advanced heart artery lesion is missed. Furthermore, if the heart artery is 40 percent to 60 percent narrowed it's almost certainly going to be missed, and a normal result will give reassurance that no heart disease is present when that is wrong. If you change the type of exercise stress test to a stress echocardiogram or stress nuclear study, the numbers may reach 85 percent accuracy in detecting a heart artery lesion that has narrowed by 70 percent or more.
In my experience in thousands of patients, there is a better approach for asymptomatic patients with risk factors. This approach has been recommended by the American College of Cardiology and supported by hundreds of peer-reviewed research studies. A direct examination of heart arteries is available at most hospitals with a multi-slice CT scanner used to perform a coronary artery calcium scan (CACS). This exam takes less than a minute and uses no contrast medication or IV injection. It is painless. The amount of radiation exposure is about 1/10th that of a cardiac catheterization or a stress nuclear perfusion scan. The heart arteries are directly visualized and calcification can be assessed and quantified as a CACS. The perfect score is zero.
As mentioned, the American College of Cardiology has given an endorsement (IIA) to the use of coronary artery calcium scans in persons with known risk factors for silent coronary disease (http://circ.ahajournals.org/content/122/25/2748.full.pdf). If someone already knows they have coronary artery disease such as a previous cardiac catheterization showing blockage, a previous heart stent, or a previous heart bypass surgery, there would be no need for a screening test of this type.
The CACS is usually not covered by insurance and may run between $100 and $200. A CACS may provide life-changing information. For example, the European Society of Cardiology said that "there is overwhelming evidence that coronary calcification represents a strong marker of risk for future cardiovascular events in asymptomatic individuals and have prognostic power above and beyond traditional risk factors." The same position statement indicated that in asymptomatic individuals a calcium score of zero was associated with a very low risk of heart events over the next 3-5 years (less than 1 percent per year). Individuals with a coronary calcium score greater than 1,000 have an 11-fold increase in risk of major events even if they are without symptoms (http://www.ncbi.nlm.nih.gov/pubmed/23058065). You might want to know that and use it to plan your lifestyle.
A CACS greater than zero can lead to changes in therapy and outcome. In a recent study, 1,005 patients with an abnormal coronary calcium score was treated with aspirin, and some received a statin to lower their cholesterol (http://www.ncbi.nlm.nih.gov/pubmed/15992652?dopt=Abstract). The average score was 370 units. After four years of follow up, patients who received a statin had a 7 percent rate of heart events like a heart attack vs. 12 percent for those who received a placebo. Other studies demonstrate that omega-3 fatty acids, aged garlic, and fruit and vegetable concentrates slow or reverse the calcification.
Heart disease remains the No. 1 killer for men and women alike in the Western world. Our efforts in February to focus on heart prevention must concentrate on early detection and treatment, with disease reversal the goal. The CACS is the "colonoscopy" of the heart and should be adopted more widely to prevent the tragic deaths that still rock our worlds.