Mobile coronary care and mortality from ischaemic heart diseases in a predominantly rural community

The mobile coronary care unit based at Coleraine Hospital was called to 155 patients in the community during a six-monthly period, 74 of whom had sustained a myocardial infarction. Over the same period, 25 of 49 patients admitted via the ordinary ambulance with suspected ischaemic heart disease had sustained a myocardial infarction and received medical care significantly later than those seen by the mobile unit. A further 12 patients out of 39 with suspected ischaemic heart disease admitted by other means (the accident and emergency department or other hospital units) brought the total number of patients admitted to hospital with myocardial infarction during the study period to 111. Overall mortality from myocardial infarction was 19·8% and was significantly higher in those ≥ 70 years of age. Nine patients with myocardial infarction seen by the mobile coronary care unit required early defibrillation (four outside hospital) and eight of these survived to be discharged. No patients admitted by other means required emergency defibrillation. Although no significant difference in mortality was demonstrated between those seen before or after three hours from the onset of symptoms or between patients admitted by the mobile unit or by the ordinary ambulance, a subgroup of patients below 70 years of age and seen by the mobile unit less than three hours after the onset of symptoms had the lowest mortality of 6·7%. Estimated overall mortality from ischaemic heart disease in this community over the study period was in excess of those deaths accounted for in this survey, implying a high mortality in those not admitted to hospital.