Cardiac time-insensitive predictive instruments (TIPIs): real-time emergency clinical decision aids and tools for the retrospective assessment of care.

In the United States, acute cardiac ischemia (ACI), including both unstable angina pectoris and acute myocardial infarction (AMI), is the leading cause of morbidity and mortality, and an enormous consumer of health care resources. Accordingly, the use of hospital and intensive care beds for patients suspected to have ACI is a major health care expense. Yet of the approximately three million patients hospitalized for suspected ACI each year, over half prove not to have true ACI, and less than half of those with ACI have AMI.1-3 These unnecessary hospital and coronary care unit (CCU) admissions represent a substantial waste; the direct costs alone are several billion dollars annually.4