Chest pain accounts for approximately 6 million annual visits to emergency departments (ED) in the United States (US), making chest pain the second most common complaint. ED evaluation focuses on distinguishing and admission of life-threatening causes of chest pain; others can be worked up on the outpatient basis.
The published guidelines of the American College of Emergency Physicians, the American Heart Association, and the American College of Cardiology suggest that, for all adult patients complaining of nontraumatic chest pain, a cardiac etiology for their presentation should be considered. History, physical examination, electrocardiogram, chest radiography, and to a lesser extent laboratory results can help differentiate ACS from other emergent diagnoses, e.g., aortic dissection, esophageal rupture, pulmonary embolus, pneumothorax, pneumonia, and pericarditis. No single feature of a patient’s history, physical examination, or diagnostic test results can diagnose ACS to the exclusion of other causes of chest pain. Based on a general impression, patient history, risk factors, ECG and levels of myocardial infarction markers it is decided whether or not to admit the patient for clinical observation.
A recent guideline says this: “Management of patients with definite ACS
Admit and immediately treat patients with new ST segment elevation or new LBBB and a history compatible with ACS, with the intent of re-establishing perfusion.1
Admit and immediately treat patients with a history and ECG (without ST segment elevation) compatible with ischemia, plus either elevated cardiac biomarkers (>99th percentile) or hemodynamic compromise (hypotension or electrical instability), for acute myocardial ischemia.
B. Management of patients with possible ACS
It is recommended that patients with a compatible history and a non-diagnostic initial ECG and cardiac biomarkers, be observed in the ED and be re-assessed at six or more hours after the initial testing with an ECG and cardiac biomarkers. Patients with a compatible history without elevated cardiac biomarkers at 6 or more hours, and an ECG not diagnostic of ischemia are considered to be at a low or intermediate short-term risk for non fatal MI or death.
For low-risk patients without an obvious alternative explanation for the chest pain an out-patient stress test within 72 hours and out-patient physician follow-up is recommended.1
When possible, discuss intermediate-risk patients with an internist or cardiologist. A stress test prior to discharge is recommended.
For both low and intermediate risk groups:
If the patient’s resting ECG is abnormal, a routine stress test will be non-diagnostic. In this scenario, stress myocardial perfusion imaging or stress echocardiography is required to detect ischemia. Therefore, referral to a facility capable of stress myocardial perfusion imaging or stress echocardiography is recommended for such patients. ”
In selected low-risk patients with pulmonary embolism, outpatient care can safely and effectively be used in place of inpatient care.
Aujesky D, Roy PM, Verschuren F, Righini M, Osterwalder J, Egloff M, Renaud B, Verhamme P, Stone RA, Legall C, Sanchez O, Pugh NA, N’gako A, Cornuz J, Hugli O, Beer HJ, Perrier A, Fine MJ, Yealy DM. Outpatient versus inpatient treatment for patients with acute pulmonary embolism: an international, open-label, randomised, non-inferiority trial. Lancet. 2011 Jul 2;378(9785):41-8.
Lindsell, CJ, Anantharaman, V, Diercks, D, et al. The Internet Tracking Registry of Acute Coronary Syndromes (i*trACS): a multicenter registry of patients with suspicion of acute coronary syndromes reported using the standardized reporting guidelines for emergency department chest pain studies. Ann Emerg Med 2006; 48:666.
Ringstrom, E, Freedman, J. Approach to undifferentiated chest pain in the emergency department: a review of recent medical literature and published practice guidelines. Mt Sinai J Med 2006; 73:499.