Telemedicine used for remote prehospital diagnosing in patients suspected of acute myocardial infarction

INTRODUCTION: In patients with acute myocardial infarction (AMI), considerable time elapses from symptom onset until initiation of thrombolytic therapy or primary percutaneous coronary intervention. Prehospital diagnosing can reduce time delays, and remote diagnosing using telemedicine may be appropriate in areas and countries where ambulances are not staffed with physicians. OBJECTIVES: To evaluate whether it was technically feasible for physicians at a remote university hospital to diagnose ST-segment-elevation-AMI (AMI(STelev)) in patients suspected of AMI, who were transported by ambulances to a local hospital. To determine associated prehospital delays and in-hospital treatment delays. METHODS: Patients carried in telemetry equipped ambulances had 12-lead electrocardiograms (ECGs) acquired as soon as possible. En route to the local hospital the ECGs were transmitted to a remote university hospital, by use of the GSM-system. The physician on call at the university hospital interviewed the patients, who were provided with cellular phone headsets, and alerted the local hospital if signs of AMI(STelev), bundle-branch-block-AMI or malignant arrhythmia were detected. Patients transported by traditional ambulances were included in a prospective control group. RESULTS: In 214 (86%) of 250 patients prehospital diagnosing was successful. Geographically related transmission problems were the primary reason for failure. Ninety-eight per cent of transmitted electrocardiograms and obtained history takings were technically acceptable for diagnostic purposes. Door-to-needle times were shorter amongst patients with AMI(STelev) who were subjected to prehospital diagnosing (n = 13) as compared with patients transported by traditional ambulances (n = 14) (38 vs. 81 min) (P = 0.004). CONCLUSIONS: It was technically feasible to use telemedicine for remote prehospital diagnosing of patients suspected of AMI. Patients subjected to prehospital diagnosing had shorter door-to-needle times compared with a prospective control group.