TEST OF THE ACUTE CARDIAC ISCHEMIA TIME-INSENSITIVE PREDICTIVE INSTRUMENT (ACI-TIPI) FOR PREHOSPITAL USE

Study objectives: To test diagnostic performance for acute cardiac isc hemia (ACI) in a manually calculated and in a computerized, ECG-calcul ated ACI time-insensitive predictive instrument (ACI-TIPI) in prehospi tal chest pain patients.Methods: We carried out prospective inclusion and data acquisition with retrospective analysis. Over a 6-month perio d, 439 adult emergency medical services patients with chest pain under went prehospital electrocardiography. Because of incomplete data, 77 c ases were excluded, leaving a study sample of 362 patients. Excluded p atients did not differ significantly with respect to age, sex, final d iagnosis, or history of myocardial infarction, heart surgery, diabetes , or stroke. ACI-TIPI probabilities of ACI were computed on the basis of the prehospital ECGs as interpreted retrospectively and independent ly by two study investigators blinded to patient outcome, with a speci ally programmed electrocardiograph, and with a computer algorithm furt her modified by logistic-regression analysis. Results: Diagnostic perf ormance on the basis of receiver operating characteristic (ROC) curve areas of the ACI-TIPI was scored, by the two physician readers,.73 and .74; and by EGG, .75. Patients with low ACI-TIPI probability (0% to 9 %) had no acute myocardial infarctions, a 2.3% incidence of angina, an d no prehospital life-threatening events. Conclusion: ACI-TIPI probabi lities of ACI as generated by a specially programmed electrocardiograp h are comparable to those based on physician ECG interpretations and m ay be useful in the prehospital evaluation of chest pain.