You've probably heard about the Generation Gap, the Income Gap, the Technology Gap, the Gender Gap, the Achievement Gap, all meant to spotlight the difference between those in-the-know, those who are not, the difference between the "haves" and the "have nots."
How about the Detection Gap?
Never heard of it? That's the wide expanse between coronary heart disease detected by conventional methods practiced in the community-like cholesterol and stress testing-and the real prevalence of disease.
If you'd like to speak to an expert in just how wide this chasm can be, we need only consult with a near-fatal victim of this gap: former President Bill Clinton. Mr. Clinton, obviously not suffering for financial resources or access to medical care, developed life-threatening coronary heart disease (severe, 95% blockages in all three coronary arteries requiring urgent coronary bypass surgery), despite five nuclear stress tests in the previous five years-all normal.
The wide expanse in detection of heart disease, a virtual Grand Canyon in the search for heart disease: that's the Detection Gap.
Despite the reduction in deaths from heart attack due to the willingness of cardiologists and hospitals to deliver acute cardiac care like angioplasty and bypass surgery, the frequency of overall heart disease has not declined. In fact, in some segments of the population (like young adults), it may actually be increasing. Surely we can do something as simple as detect the number one killer of American men and women. And, once detected, we can certainly do something about it. It seems obvious. The most common and frequently fatal disease in the U.S. and you'd think that this would represent the number one priority for your primary care doctor, his friends and colleagues, and the medical system.
The problem is that the standard approach to coronary heart disease detection is a relatively simple formula. High cholesterol is usually used as the starting point for deciding whether risk for heart disease is present. Then, in conventional practice, one of three things are sought in the effort to diagnose coronary heart disease:
1) Symptoms of heart disease like chest pain or breathlessness.
2) An abnormal EKG or abnormal stress test.
3) A catastrophe like heart attack or sudden cardiac death.
By this equation, the American Heart Association (AHA) estimates that 7.5% of American men and women have coronary disease (American Heart Association, 2007 Update). (In all fairness, the AHA includes all American adults over 18 years old.)
However, I'd say the number is more like 48%, i.e., 48% of the U.S. adult population over 40 years old has coronary artery atherosclerotic plaque to some degree, from mild to severe. Now, my definition encompasses much earlier phases of heart disease, years or even decades before symptoms are present, before a stress test is capable of detecting it, and danger is not imminent. But the disease is there nonetheless. Give it a chance, however, and many will eventually be detectable by standard methods, many others will die.
In other words, following the Heart Association's method to identify potential future victims of heart disease, we will mis-diagnose, mis-classify, overlook, and simply fail a great many-no, most-people with hidden heart disease.
Why 48%? That's the number I arrive at when I ask: How many men and women have CT heart scan scores above zero representing measurable coronary atherosclerotic plaque?
The enormous difference between the 7.5% of Americans with crystal-clear, life-threatening heart disease and the 48% who have coronary plaque is the Detection Gap. The Gap is big, encompassing tens of millions of people.
If heart disease is detected by a CT heart scan, it tends to be early, before catastrophe strikes. By the conventional approach to detection of heart disease, in contrast, you often don't know you have it until catastrophe strikes and you're lying on a hospital gurney being wheeled off to a major procedure.
If heart disease is detected by waiting for the appearance of symptoms, then a stress test (usually nuclear) is followed by a heart catheterization, stents, bypass, etc. So there's more than a Detection Gap. There's also a difference in the sorts of therapies chosen. There's certainly a difference in cost: a Health Expense Gap?
In my view, there is no rational reason not to close the Detection Gap. While CT heart scan scores aren't perfect, they're darn close. Heart scans hold potential to shrink the Detection Gap to around 2%. We'd save millions of lives and billions of dollars. If you're one for New Year's resolutions, a heart scan is a great place to start. It's certainly better than a cholesterol test, a stress test, or waiting for something to hit you on the side of the head.
Published On: January 16, 2008