Dr. Anil Makam, Professor at UT Southwestern and lead author of a new study published in JAMA Internal Medicine entitled, “Use of Cardiac Biomarker Testing in the Emergency Department,” suggests that inappropriate testing practices regarding acute coronary syndrome are currently being used in emergency rooms.

According to Makam, patients are being tested for markers that do not show any signs of having actually suffered a heart attack. As a consequence, the cost of treatment increases due to the number of false positives. Therefore, further tests and unnecessary consultations are required, leading to patient anxiety.

Data regarding patients and their consultation in emergency rooms was provided by the National Hospital Ambulatory Medical Care Surveys. Dr. Makam analyzed almost 45,000 adult visits to emergency rooms across the country in 2009 and 2010, and he compared symptoms to which tests were ordered. It is important to note that, for the purpose of the study, the heart attack symptoms considered were chest pain, vomiting, nausea, upper abdominal pain, heartburn, palpitations and shortness of breath (or other breathing problems), fainting, general malaise, dizziness, fluid abnormality, sweating, jaw pain, neck pain, arm pain or edema. If a patient exhibited one of these symptoms — even only one — he or she was considered to be showing signs of a heart attack. For cardiac biomarker tests, creatinine kinase MB, troponin T and troponin I were used.

Although the scope coronary symptoms is broad, 29.7% of those tested for the cardiac markers showed no symptoms of having a heart attack. Furthermore, among the patients that were hospitalized after their emergency room visit, 35.4 percent were screened for cardiac markers despite the fact that they displayed no symptoms of heart attack.

“Extrapolating our findings, our extremely conservative estimate is that there were 1.7 million individuals with a false-positive cardiac biomarker test in the U.S. over those two years,” said Dr. Makam in a press release. Dr. Makam explained that testing practices were the main predictor of the cardiac biomarker testing and not the symptoms as he expected.

Nevertheless, Dr. Oanh Nguyen, senior author of the study and Professor at the UT Southwestern, explained that there might be a reason behind the prescription of tests in the absence of symptoms: “First, providers who are ordering the tests may be fearful of missing a diagnosis and they are ordering everything but the kitchen sink in terms of tests, ‘just in case; second, providers may be over-ordering tests in situations where they are uncertain of a diagnosis, and are hoping that the tests will help them make a quick diagnosis and finally, providers may simply be following institutional guidelines.”