This story about the use of ultrasound for arterial screening is confusing, thinly reported and potentially misleading.
It fails to make a clear distinction between the use of ultrasound as part of conventional diagnostic practice and its more recent, commercial use for screening asymptomatic people. The report suggests that the development of more portable and less expensive devices for conventional use will lead to more widespread use in screening, which is not necessarily the case.
It fails to describe existing research on arterial screening. It fails to clarify whether any of the sources has a conflict of interest.
A reader who has an elevated risk for heart disease but has no symptoms would not get from this story what he or she needs: A view of what the research shows, and an even-handed assessment about the risks and benefits of screening.
The story makes a serious error when it states, "…because for one-third of heart disease sufferers, the first symptom is dropping dead of a heart attack." Not only is this an example of disease-mongering, it appears to be a garbling of the more commonly cited American Heart Association statement that "In 57 percent of men and 64 percent of women who died suddenly of CAD, there were no previous symptoms."
The article reports that at a hospital the test costs $295 and from an indepdendent ultrasound technician it costs $180. The article indicates that insurers usually don’t pay for the scans when used for screening purposes.
However, the story would have been stronger if it had explored the costs of unnecessary medical procedures and treatments that may be triggered by an inaccurate screen.
The article does not cite any research demonstrating the benefits or risks of ultrasound arterial screening–all the supporting comments are anecdotal or are based on broad descriptions of clinical practice.
The use of speculative data to illustrate how many people might be over- or under-treated as a result of population screening is very useful. But it does beg the question of what is known about the screen’s accuracy.
The article briefly mentions the possible risks of overtreatment but does not detail them. And some, such as unnecessary angiograms or long-term drug therapy that may have side effects and high cost, are considerable. The article also does not mention the risk of stroke or death from surgery, or the risks that a false negative test will discourage a patient from adopting healthy lifestyle changes.
The article describes some research currently taking place, but it does not look at existing research into the topic. The article notes that the American Heart Association finds insufficient evidence of benefit to justify a recommendation for screening, but does not follow that up with AHA experts (or experts with the many other groups that do not recommend screening). Based on existing data, the following groups do not recommend routine carotid screening in the general population: the National Stroke Association, the Canadian Stroke Consortium, the American Stroke Association/AHA Stroke Council, the American Society of Neuroimaging and the Society of Vascular and Interventional Neurology. The latter group just published their guideline in 1/07.
The article briefly refers to a study that suggested screened patients exercised more regardless of what the ultrasound showed, but does not go into detail.
The article’s lede overpromises what this technology may contribute to diagnosing asymptomatic heart disease by screening populations.
The article implies that people with carotid disease have coronary heart disease; statistics suggest only 25 to 60 percent do. The article includes the example of a 41-year-old active woman with no risk factors other than family history as having carotid disease. Statistically this is the exception, not the rule.
There is no evidence in the story to justify the speculation that arterial ultrasound devices will be as common in doctors’ offices as stethoscopes.
The article does not report on possible conflicts of interest that the physicians quoted may have. Because there are clearly financial incentives involved in broader application of ultrasound for screening, the article should have clearly stated whether the researchers had a financial conflict of interest. It should have explored the role the device makers are taking in spreading use of the technology in the absence of evidence of benefit.
The article includes anecdotes from two patients, one satisfied and one who is satisified but who has a financial interest in the devices. Adding a patient who had been misdiagnosed with screening would have added balance.
The article does not mention other methods of assessing heart disease risk in asymptomatic people. Nor does it mention modifiable and treatable risk factors as an alternative to imaging.
The article suggests that different types of arterial ultrasound are available in a variety of ways, from traditional diagnostic procedures ordered by cardiologists to shopping center quick-scans used as screens.
It’s not clear, however, how frequently this procedure is used for screening and where it is available for that purpose. Greater availability is predicted but current availability is not specified. A reader interesed in a scan would not be sure, from this article, where to turn.
The article does not distinguish clearly between the use of arterial ultrasounds for diagnostic purposes in the ER or in people at high risk for heart disease (which is not novel) and its use for screening a broad population or a self-selected group (which is more novel, though how novel is not made clear).
There is no evidence that the article was based on a press release.