Experts Debate CT Scan for Artery Disease 

	12/30/98 - Electron-beam computed tomography (CT) is a useful way to detect coronary artery blockages that can trigger heart attacks and strokes, according to two papers published in The New England Journal of Medicine, December 31, 1998.
	But in two companion pieces, other experts voice concern that
the test is being used to make money for hospitals and imaging centers without enough scientific justification.
	In the first paper, researchers report that electron-beam CT is a reliable way to monitoring benefits of cholesterol-lowering therapy. Dr. Paolo Raggi, of the Electron Beam Tomography Research Foundation in Hendersonville, Tennessee studied 149 patients who did not have chest pain or other symptoms of artery disease. Most of the patients (70%) were on cholesterol-lowering drug regimens.
	On 2 occasions, 12 to 15 months apart, the research team took CT scans of the patients' coronary arteries. All untreated patients had an increase in artery calcium volume between the first scan and the second. The degree of calcification is considered an indicator of coronary artery disease.
	Among the treated patients, the calcium-volume score decreased
only in the 65 patients who had low levels of LDL cholesterol, the "bad" cholesterol that is most strongly implicated as a cause of blocked arteries.
Raggi's group concluded that it may be worthwhile for patients who do not have symptoms to have a CT Scan as screening for coronary artery disease.

	In a separate study, Dr. Stephan Achenbach of the University of Erlangen-Nurnberg in Germany, found that the diagnostic value of CT Scan compares to that of cath, the standard method for evaluating heart and blood vessels. The researchers did CT Scans of 4 coronary arteries in each of 125 patients who were scheduled to have a cath. Of the 500 images, 25% could not be used due to technical problems.
	Compared with cath, a more time-consuming and expensive imaging test, CT Scan was 92% correct at finding coronary artery disease that existed and 94% correct at ruling out coronary artery disease that didn't exist. The negative predictive value of the test - the proportion of patients that were correctly identified as not having coronary artery disease - was 98%.
	Achenbach's team suggests that, if the technical problems can be solved, CT may be useful for ruling out coronary artery disease in patients who are at low risk, and also for monitoring progress of patients who have had an artery-clearing procedure, such as bypass surgery.
	Electron-beam CT is "a promising, non-invasive method that may help overall risk testing," agrees Dr. David Celermajer, of the University of Sydney in Australia. But Celermajer cautions that routine use of electron-beam CT is premature. The cost effectiveness of the scans and whether test results
correspond to later development of heart attacks or strokes, must be studied, he says.
	"Despite the American Heart Association's call for patience, news reports in the press as well as mass-media advertising have promoted the test to the general public," note doctors Taylor and O'Malley, of Walter Reed Army Medical Center. Taylor and O'Malley point out that many hospitals and imaging centers do most of their CT scans people who "self-refer" instead of having the test ordered by a doctor.
	"Is CT screening for coronary calcium scientifically valid?" they
ask. "Or does the profit motive over-ride best clinical practice?"

From: The New England Journal of Medicine 1998;339:1964-1971, 1972-1978, 2014-2015, 2018-2020

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High Blood Presssure Patients Need More Treatment

	12/30/98 - Doctors "are not aggressive enough" in their treatment of patients with high blood pressure, according to a report in the December 31, 1998 issue of The New England Journal of Medicine.
	"In our study, doctors often did not increase the dose of high BP medications or try new treatments in patients with high blood pressure," researchers at Bedford Veterans Affairs Hospital in Bedford, Massachusetts, and Boston University say.
	They reviewed the care of 800 older, high BP men seen at one of 5 New England VA hospitals. The patients averaged 6 visits per year over the 2-year study period. The research team reports that, despite monitoring and treatment, 40% of patients continued to have blood pressure readings above 160/90.
	Doctors were slow to adjust high BP therapy. In the past, much of the poor patient response to BP therapy has been blamed on patients who don't seek medical help or who don't take medications as prescribed. According to the
Massachusetts team, the regular use of free or low-cost VA health services by their subjects suggests that "poor control of blood pressure could not be explained by lack of access to medical care." These researchers do not blame BP control problems on non-compliance.
	The study authors conclude that "doctors must accept some responsibility for the problem." They advise doctors to "examine their approach to individual patients and identify situations in which more aggressive management may be appropriate."

From: The New England Journal of Medicine 1998;339:1957-1963