Analysis of the treatment of acute myocardial infarction using ambulance records in Japanese cities

By means of ambulance records, the current state of medical services for the treatment of acute myocardial infarction (AMI) was investigated in Chiba City and Ichihara City, Japan. From all patients transported by ambulance personnel in 1992 (n=31,191), 388 patients who were admitted within 2 weeks after the onset were studied. Types of admitting institution, diagnoses, medical treatments and prognoses were investigated. According to medical records, 168 patients fulfilled the criteria of definite AMI and were admitted alive. Percutaneous transluminal coronary angioplasty (PTCA) and recanalization (PTCR) were performed on 54 and 6 patients, respectively. The hospital case-fatality rates were lower in the patients who underwent emergency PTCA or PTCR than in the others. Emergency-PTCA or PTCR, and admission to coronary care units (CCU) or institutions equipped with coronary angiography, decreased the fatality risk, even after considering age, sex, and disease severity. These results show the importance of the selection of institutions for AMI patients. Because 40% of definite AMI patients were sent to institutions without CCU, it is essential that enough CCU are available through an improvement in cooperation between the various types of institutions, and in the proper transfer of AMI patients to CCU.