EARLY IDENTIFICATION OF PATIENTS AT LOW-RISK OF DEATH AFTER MYOCARDIAL-INFARCTION AND POTENTIALLY SUITABLE FOR EARLY HOSPITAL DISCHARGE

Objectives-To find (a) whether data available shortly after admission for acute myocardial infarction can provide a reliable prognostic indi cator of survival at 28 days, and (b) whether such an indicator might be used to identify patients at low risk of death and suitable for ear ly discharge. Design-Retrospective analysis of data collected on patie nts admitted to a coronary care unit for acute myocardial infarction. A validation sample was selected at random from these patients. Settin g-Coronary care units in Perth, Western Australia. Subjects-6746 patie nts aged under 65 and resident in the Perth Statistical Division who d uring 1984-92 were admitted to a coronary care unit with symptoms of m yocardial infarction. Main outcome measures-Sensitivity and specificit y of several models for predicting survival at 28 days after myocardia l infarction, and detailed performance characteristics of a particular model. Results-Patients with a pulse rate of 100 beats/min or less, a ged 60 or under, and with symptoms typical of myocardial infarction, n o past history of myocardial infarction or diabetes, and no significan t Q wave in the admission electrocardiogram had a very high chance of survival at 28 days (99.2%). These patients made up one third of all p atients studied. Conclusion-The prognostic index identifies patients v ery soon after admissionwho are at low risk of death and potentially e ligible for early discharge from hospital or the coronary care unit. C omputing the index does not need complex cardiac investigations.