BOSTON—One of the more expensive questions any emergency physician can ask is: Does the patient complaining of chest pain have unstable angina (UA) or non-ST-segment elevation myocardial infarction (NSTEMI)?

“How do we know if a patient is the real deal or just another chest pain?” said emergency physician Tarlan Hedayati, MD, associate program director at Cook County Hospital in Chicago. “Eight to 10 million come into our emergency departments annually for chest pain. More than half of them are going to get a comprehensive work-up. Very, very expensive—$10 billion to $13 billion annually. Less than 10 percent of them are actually diagnosed with ACS (acute coronary syndrome), so we need to figure out a way to risk stratify these patients.”

Dr. Hedayati presented “Therapy for Non-ST Elevation ACS: Update 2015,” at ACEP15 on Tuesday. She highlighted the “2014 Guideline for the Management of Patients with Non-ST Elevation Acute Coronary Syndromes” (NSTE-ACS), released last fall by the American College of Cardiology/American Heart Association (ACC/AHA) as the first full revision in seven years.

Noteworthy changes to those guidelines included recognizing that the pathophysiologic continuum of UA and NSTEMI often make them indistinguishable; swapping the terminology of “initial conservative management” to “ischemia-guided strategy”; and noting that while early invasive strategies for NSTE-ACS patients presenting with significant coronary artery disease (CAD) is generally accepted, low-risk patients can “substantially benefit from guideline-directed medical therapy.”

“Guideline-directed medical therapy has not always been optimally utilized and advances in noninvasive testing have the potential to identify patients with NSTE-ACS at low-intermediate risk to distinguish candidates for invasive versus medical therapy,” the ACC said in a statement at the time.

Dr. Hedayati told a crowded room Tuesday that patients where NSTE-ACS is definite or likely can be handled most often with aspirin and a referral to cardiology. The use of a second antiplatelet therapy—before percutaneous coronary intervention (PCI)—can be added as well.

“For unstable angina/NSTEMI patients who are going for a cardiac cath…you’re going to give them their aspirin and you’re going to start them on clopidogrel or ticagrelor, depending on what you have,” Dr. Hedayati said. “For patients who are being admitted and are managed conservatively, which is the vast majority of our patients, we just give them their aspirin and get them admitted. The team upstairs can start the rest of the drugs.”