Chest pain centers (CPC) were initially developed to facilitate rapid treatment of patients with acute myocardial infarction and they have subsequently evolved to include safe, cost-effective management of low risk patients presenting with acute chest pain. The number of CPCs has grown continuously and it was recently estimated that 30% of U.S hospitals have a CPC, which total -1,200 in this country. The necessity for improved management of low risk patients, who comprise the majority of those presenting with chest pain, has been a ma or factor in the increase of CPCS. Thus, the emphasis of CPCs varies from those which focus on high risk patients and those in which the primary aim is to decrease unnecessary admissions of low risk patients with chest pain, who comprise -75% of patients presenting to the ED with this symptom. In the latter group, the goal of the CPC is to resolve the dilemma presented by inadvertent discharge of patients with acute coronary syndromes, which still occurs in 2% of patients in this country with high morbidity and mortality - while minimizing unwarranted admissions.

CPCs vary in form, from those that entail a distinct, structural unit or area to those that are based more on process and coordination ("virtual units") of skilled personnel (cardiologists, emergency physicians and nurse specialists) and dedicated equipment. The majority of CPCs in this country are in the latter category. Fundamental to the goals of the CPC is a protocol-driven, systematic approach to patient management that promotes optimal application of current standards of care. Guidelines, or critical care pathways, are commonly utilized. These strategies 1) afford rapid initiation of crucial therapy in patients with high risk acute coronary syndromes and 2) stratification of clinically low risk patients into those requiring admission and those who can be safely discharged and managed as outpatients.

In addition to a directed history, physical examination and administration of aspirin, current recommendations include acquisition and interpretation of an ECG in IO minutes to detect myocardial ischemia/injury and determine the indication for coronary reperfusion and other antiischemic therapy, which should be initiated within <30 minutes of presentation. These patients are recognized as high risk and are admitted to the inpatient service. By contrast, low risk patients with chest pain, characterized by stable clinical status and a normal or near-norrnal ECG, have been increasingly managed by a variety of accelerated diagnostic protocols. These have usually comprised 6-12 hours of monitoring and serial cardiac biomarkers. If this evaluation does not reveal an acute coronary syndrome, exercise testing or other noninvasive cardiac stress study is usually performed. If this test is negative, the patient is discharged; a positive finding results in admission for further evaluation.

Recent data demonstrate that rapid coronary reperfusion therapy in high risk patients is enhanced by a CPC strategy. It has also been amply demonstrated that accelerated diagnostic protocols applied in CPCS, in patients identified as low risk on the basis of the initial presentation, are safe and accurate. Length of stay has been consistently reduced and subsequent risk in patients with negative evaluations is low. Initial data indicate that this strategy, as implemented in a CPC, is cost-effective.