Impact on the care of the emergency department chest pain patient from the chest pain evaluation registry (CHEPER) study.

This study examines the question of whether chest pain observation units increase the proportion of chest pain patients with an extended evaluation for cardiac ischemia ("rule out myocardial infarction [MI] evaluation"), decrease the number of missed MIs, and decrease costs. This is a multiple site registry study of 8 established chest pain observation units (complying with the American College Emergency Physician's Observation Section's standards) compared with previous studies on chest pain evaluation without the use of observation (5 studies, 12,405 patients). A total of 23,407 of 444,189 emergency department patients (5.