Concerning direct-to-consumer screening for suspected risk evaluation, last week we looked at various scenarios whereby such screening might be performed. Here are the answers:

You have a family history of stroke. You yourself have occasional heart palpitations, a brief ‘fluttering in your chest’ lasting minutes to a few hours sometimes. Surfing the web, you learn that some heart arrhythmias can predispose to clots, embolize to the brain, and cause TIA’s or strokes. You have chatted with others, have found that this condition is not all that rare, and that the resulting stroke can be debilitating, sometimes even lethal.

You are a part of your community center, or church group, or service organization. Your leadership group has been approached by a direct-to-consumer cardiovascular risk assessment organization. For a small fee, they will do electrocardiograms on any participants, screening them for atrial fibrillation. In return for your allowing them to come in to test the membership, and the community at large, they will pay your organization a handsome honorarium. The committee turns to you for advice. What do you tell them?

You tell your committee this is little better than a scam, and will do more harm than good. Most instances of rapid, irregular, arrhythmic palpitations that predispose to stroke (atrial fibrillation) are paroxysmal. In other words, the spells occur in brief periods of time when clot, embolism and stroke may occur, interspersed with much longer periods of normal heart rhythm. In a person having the condition, a single electrocardiogram is likely to be normal, giving a false negative result. The person is given a false sense of security, does not undergo a recommended screening procedure, and may well have a stroke in any event. To give weight to this argument, the American Heart Association and American College of Cardiology Foundation both have analyzed such screenings and have found them to be worthless. Now, you may say that cardiologists merely want to engage in more expensive testing and cut your community center out of the action — but then you are simply a conspiracy theorist of the worst order.

There is another reason, perhaps not as compelling, but worthy of your notice. You and your community center signed on for this. You have received payment from the screening organization. This is a contract of sorts. Now comes a person with a serious, life-threatening cardiac condition evident on the electrocardiogram you obtain at your center, but not of the arrhythmia variety you are screening for. His “test” is reported as “normal” and he drops dead two weeks later. Who do you think will be liable?

You have that family history of stroke. You know, through reading these columns, that one cause of stroke is the buildup of cholesterol plaque in the carotid arteries of your neck. You also know that a simple noninvasive ultrasound examination of these vessels can visualize the plaque, estimate its severity. A vascular surgery group from The Big City will be conducting a carotid artery stenosis screening clinic at the local high school, provided of course they get permission from the school board. You are on the school board, and they turn to you for advice. What’s your take?

This scam is worse than the last, because here we have the sin of commission as well. Carotid ultrasound in an elderly population will demonstrate frequent cholesterol plaque, which in an asymptomatic person, is called in this case a false positive result. Asymptomatic individuals with cholesterol plaque have low mortality and are more at risk from complications of further testing and from treatment (surgery). The U.S. Preventive Services Task Force recommends against such screening. Should a bad result ensue, medical-legal liability could well include your school board. Yet, patients have told me such “screening carotid artery clinics” are frequent in the shopping malls in Florida frequented by the elderly. This scenario is very similar to the next, where false positive results lead to unnecessary surgery:

You’ve read this article in the Sunday Parade magazine on peripheral arterial disease and suddenly, you see amputees everywhere. Your morning coffee buddies are thinking they should get screened for this. They have seen TV ads for screening clinics, think maybe they can kill two birds with one stone by getting one of these clinics to come to the community. They will pay the community quite well just for the opportunity to come in and test its citizens. How can you go wrong with that? What do you tell your buddies?

This is the peripheral arterial disease ankle brachial index, or Doppler ultrasound, or some combination thereof. The false positive rate is very high, the test is of no use, and resulting unnecessary surgery obviously carries unacceptable risk and morbidity. Some doctors (who promote the screening and profit handsomely from it) fervently believe in this stuff, but remember, one can be “often wrong, but never in doubt.”

That’s it for this week. We’ll do the last three scenarios next Sunday.

Michael A. LaCombe is a cardiologist at MaineGeneral Medical Center. E-mail questions to: housecalls@mainegeneral.org

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