CHICAGO—Coronary CT angiography effectively identified chest pain patients who could be safely sent home from the emergency department (ED), according to a study presented at the American College of Cardiology's annual meeting.
Researchers included 1,370 patients who were older than 30 and presented to one of five EDs with low-to-intermediate risk of acute coronary syndrome (a score of 0 to 2 on the Thrombolysis in Myocardial Infarction Risk Score). The patients were randomized—462 to usual care and 906 to coronary CT angiography. Of those 906 patients, 640 had a negative angiogram (less than 50% stenosis in all coronary arteries). The researchers followed the patients for the next 30 days and in that time, none of those with negative CTs had a myocardial infarction (MI) or cardiac death.
The study also found that patients in the CT angiogram group had a higher rate of discharge from the emergency department (49.6% vs. 22.7%) and a shorter length of stay (median, 18.0 hours vs. 24.8 hours; P<0.001). The researchers are continuing to follow these patients to determine whether the cost-effectiveness and safety of the CT scanning arm is maintained for a year after the ED visit, said lead study author Harold Litt, MD, PhD, during a press conference at the ACC meeting.
Dr. Litt also said the study's results show that using a CT angiogram can be an effective way to determine which chest pain patients don't need to be admitted to the hospital. “ED physicians want to feel confident that when they send somebody home, those patients are going to be safe,” he said. The upper limit of the confidence interval for the 30-day MI rate in negative CT patients was 0.57%, he noted, below the 1% risk that had been the safety goal.
The CT angiogram also detected coronary disease more often than usual care did (9.0% vs. 3.5%). The researchers did note some limitations of the study, including that 16% of patients randomized to a CT did not receive it, most often because their heart rate was too high. They also cautioned that the results should not be extrapolated to higher-risk patients, and that the scanning does cause additional radiation exposure. The study was presented at the conference and published online by the New England Journal of Medicine on March 26.
—By Stacey Butterfield, Associate Editor