The "SHAHAL" experience in Israel for improving diagnosis of acute coronary syndromes in the prehospital setting

The diagnosis of acute coronary syndromes is frequently missed, and many hi gh-risk patients fail to be admitted to hospital. The aim of this study was to assess the value of cardiac markers in ruling out acute ischemic events in patients with symptoms of possible cardiac origin and nondiagnostic ele ctrocardiograms. The data collected between May 1999 and April 2000 for thi s prospective cohort study were retrieved from the records of 777 consecuti ve prehospital patients (mean age 70 years, 62.9% men) whose symptoms laste d for 6 to 48 hours, who were treated by mobile intensive care teams, and f or whom the physician could not reach a clear-cut decision whether they sho uld be taken to hospital or left at home. The cardiac markers, creatine kin ase (CK-MB), myoglobin, and troponin I, were measured at the scene using a rapid Stat kit to qualitatively detect their presence in whole blood sample s. Results were determined after 15 minutes at the scene. The assay was pos itive in 30 patients, 11 of whom had a definite cardiac diagnosis (acute my ocardial infarction in 4 and unstable angina pectoris in 7). Positive and n egative predictive values of the assay for detecting a significant coronary event were 36.7% and 100%, respectively. Of the 747 patients with a negati ve result, 6 patients had a false result (1 with myocardial infarction and in 5 with unstable angina) (99.2% negative predictive value). Thus, cardiac markers are useful in ruling out high-risk coronary syndromes in the preho spital setting when the clinical presentation and electrocardiogram are inc onclusive. (C) 2001 by Excerpta Medica, Inc.