Acute myocardial infarction: an easy diagnosis in general practice?

In the imminent myocardial infarction Rotterdam (IMIR) study, contacts by patients with their general practitioners for symptoms of potential coronary artery disease were registered. Those who had acute myocardial infarction were diagnosed on the basis of the modified World Health Organization criteria, and those with this definite diagnosis were then compared with the initial diagnosis made by the general practitioner at the moment of contact without laboratory assistance.Of the 1,343 patients included in the study, 93 (seven per cent) had ;definite' acute myocardial infarction and another 37 (three per cent) had ;possible' acute myocardial infarction according to the diagnostic criteria used.At the time of contact with the general practitioner 41 (44 per cent) of the 93 patients with definite myocardial infarction were recognized as such by the general practitioner, while in another 31 (33 per cent) the general practitioner diagnosed ;imminent' myocardial infarction.Of the 1,213 patients free of acute myocardial infarction at the time, 40 (three per cent) were incorrectly diagnosed by the general practitioner as having ;acute' myocardial infarction.In the 22 patients who in fact had acute myocardial infarction but in whom the general practitioner did not make this diagnosis at the time, it was found that there was an absence of physical signs and, similarly, in patients who subsequently did not have infarction the presence of physical signs was related to a falsepositive general practitioner diagnosis of myocardial infarction.In view of the inaccuracy of the general practitioner's provisional diagnosis of acute myocardial infarction, we believe that electrocardiogram and enzyme tests should be carried out systematically in all patients who present to general practitioners with symptoms of potential coronary artery disease. Laboratory support should be readily available and we support the idea of having a special diagnostic service.