We conducted a feasibility study of a mobile unit capable of recording a 12-lead electrocardiogram (ECG) and transmitting it to a receiving hospital workstation. Two ambulances were equipped with the mobile unit and the ECGs recorded were compared with standard ECGs recorded on the hospital ward after admission. In six months, 62 patients participated in the study The ambulance crew transmitted messages to the coronary care unit for 56 patients. Thirty-five patients were directed to the coronary care unit, four were directed to the emergency department as no beds were available and then transferred to the coronary care unit later, and the remaining 23 were directed to the emergency department. Comparative hospital and mobile ECCs were available for 31 patients. Although the mobile unit recorded smaller R- and S-wave deflections than on the standard hospital ECGs, the medical and nursing staff were able to differentiate between normal and abnormal tracings. The mobile unit may be useful to triage patients with chest pain before they reach hospital.