The extent of coronary artery disease in diabetic patients with myocardial infarction: an ECG study.

In 91 non-diabetics (age 63 +/- 12, mean +/- SD, years range 31-94 years) and 85 patients with known diabetes or clearly abnormal levels of HbA1c (age 66 +/- 10 years, range 36-87 years) electrocardiograms were analysed sequentially after acute myocardial infarction (AMI). There was no significant difference in infarct site between the two groups. Generalized ischaemic change without ST elevation was seen in 33% of diabetics and 22% of non-diabetics (p greater than 0.1). In patients with transmural AMI, cardiogenic shock (CGS) was significantly commoner in diabetics (relative risk 3.1, CL 1.2-8.1) but there was no difference in the frequency of reciprocal change between the two groups. In both diabetic and non-diabetic patients the development of cardiogenic shock was more frequently associated with the presence of reciprocal change, the difference reaching significance in the diabetic group (chi 2 = 4.4, p less than 0.05). Thus cardiogenic shock in both diabetic and non-diabetic patients with AMI may be associated with the presence of extensive coronary artery disease, but differences in the prevalence of extensive disease do not explain the predisposition of diabetic patients to CGS.