Use of Echocardiography in the Evaluation of Chest Pain in the Emergency Department

Chest pain is one of the most common complaints that brings a patient to the emergency department (ED). The differential diagnosis of chest pain is broad and includes cardiac as well as non-cardiac diseases. One of the initial goals in the ED evaluation of a patient presenting with chest pain is to rapidly and accurately diagnose the presence or absence of acute coronary syndrome. The diagnostic accuracy of the initial routine evaluation is often limited and results in frequent admissions for patients presenting with chest pain for further diagnostic testing. Echocardiography has a high sensitivity and specificity for the diagnosis of acute myocardial infarction. Tissue Doppler imaging with strain and strain rate (SR) measurement is a new echocardiographic technique, which enables accurate assessment of regional left ventricular systolic and diastolic function. Prior studies have shown that abnormal strain and SR are highly sensitive markers of ischemia. Acute ischemia induces early systolic thinning and a delay in the onset of systolic thickening, a progressive decrease in the rate and degree of maximal systolic thickening, and an abnormal ischemia-related thickening which occurs after aortic valve closure. A major obstacle to the routine use of echocardiography in the ED is the need for portable studies, using heavy, bulky portable echo machines. There are currently available portable hand-held echo machines (GE-Vivid I) that produce high quality images and offer an opportunity to incorporate echocardiography into routine practice in the ED. This study will use of early, portable echocardiography, with detailed assessment of wall motion and left ventricular function by strain and strain rate measurements, for the evaluation of chest pain in the ED. It is hypothesized that an early with detailed left ventricular function assessment will be highly sensitive and specific for the diagnosis of myocardial ischemia, and will enable rapid triage of patients who present to the ED with chest pain.