STANFORD, Calif. An invasive heart test used routinely to measure heart function is being dramatically overused, especially among patients who recently underwent similar, more effective tests, according to a new study from the Stanford University School of Medicine.
"This adds both risk to the patient and significant extra cost," said first author of the study Ronald Witteles, MD, assistant professor of cardiovascular medicine and program director of Stanford's internal medicine residency training program, who called the rates of unnecessary use "shockingly high."
The procedure, called left ventriculography or left ventriculogram, was developed 50 years ago to assess how well the heart functions by using a measurement method called "ejection fraction" the percentage of blood that gets squeezed out with each heartbeat. The investigators found that it is routinely performed as an add-on procedure during a coronary angiogram, a separate heart-imaging test, at an extra cost of $300.
Over the years, several less-invasive and often superior methods of measuring ejection fraction have emerged, such as echocardiograms and nuclear cardiac imaging, making the use of left ventriculography questionable at times, the study states.
The study appears online this month in the American Heart Journal.
Several years ago when Witteles was a cardiac fellow, he and his colleagues noticed a great deal of variation in whether cardiologists would order the procedure, often in similar patient cases, he said. This seemingly arbitrary use of left ventriculography led to the idea for this study.
Researchers first set out to determine exactly how often the procedure was conducted. They examined a national database of about 96,000 patients enrolled in Aetna health benefits plans in 2007 who underwent a coronary angiogram during that year. The data showed left ventriculography was performed 81.8 percent of the time whenever an angi
|Contact: Tracie White|
Stanford University Medical Center