CHICAGO — Coronary computed tomography angiography is a rapid and reliable test to identify which patients presenting to the ED with possible acute coronary syndromes can safely be discharged, according to results of a phase 4 trial presented at the American College of Cardiology’s 61st Scientific Sessions.
The data come from the first CV study conducted by the American College of Radiology Imaging Network (ACRIN). For the ACRIN PA 4005 study, researchers randomly assigned 1,392 low-to-intermediate risk patients at five centers to receive traditional care or coronary CTA in a 1:2 ratio. Health care providers at each site made all decisions about tests and treatment for the traditional care group patients on an individual basis. The coronary CTA group adhered to a three-part protocol: tests to measure blood levels of two substances associated with heart damage and risk for MI or stroke, coronary CTA and discharge if test results were negative.
None of the 640 patients with a negative coronary CTA experienced MI or mortality within 30 days after discharge (30-day event rate of <1%). One serious adverse event was reported in each group. Coronary CTA was a better indicator than stress tests for identifying patients with CAD (9% vs. 3%). Use of coronary CTA also resulted in a greater number of patients being discharged rather than admitted to the hospital (50% vs. 23%) and reduced median length of hospital stay (18 hours vs. 25 hours).
“Even with the methods we have available today with CT, there remain a substantial number of patients with complaints of chest pain who were discharged from the ED and wound up experiencing a heart attack — approximately 3% of discharged patients who were admitted with chest pain,” Harold I. Litt, MD, PhD, chief of CV imaging in the department of radiology at the Perelman School of Medicine, University of Pennsylvania, said at a press conference. “These discharged patients are at very high risk of having a bad outcome, which is why we need some type of evaluation that brings that number as close to 0% as possible.”
Researchers will next examine costs associated with these findings and will analyze 30-day and 1-year utilization and cost effectiveness. In-hospital and 30-day cost data are expected within 6 months. Researchers also recorded data about arterial plaque that will be studied in the future.
For more information:
Disclosure: Dr. Litt reports no relevant financial disclosures.
David E. Winchester
The researchers do an excellent job of proving in a randomized trial what we have seen from observational studies of coronary CTA in the ED setting, namely reductions in admission rates and length of stay as well as improvement in detection of CAD. An especially important aspect of the study’s design was to include enough patients to statistically show that for patients with a normal coronary CTA the risk for death or MI within 30 days of discharge is zero. This provides clinicians with strong evidence to support the practice of discharge after a normal coronary CTA while feeling confident that patients will be safe and likely free of CV events for 30 days thereafter.
– David E. Winchester, MD, MS
Assistant Professor of Medicine, Division of Cardiology
University of Florida
Disclosure: Dr. Winchester reports no relevant financial disclosures.