The ECG in Diabetes Mellitus

Abstract

Case Presentation: A 42-year-old man underwent routine blood tests that revealed a fasting blood glucose value of 105 mg/dL and hemoglobin A1c of 6.2%, resulting in a diagnosis of early type 2 diabetes mellitus. Resting 12-lead ECG showed deep S-wave in LIII and R-wave in aVL, indicating early left ventricular hypertrophy; no signs of cardiac autonomic neuropathy (CAN) were found. Stress ECG demonstrated a 2-mm depression of the ST segment. Inasmuch as this finding represents high risk for future cardiovascular disease and mortality, the patient was given strict diet restrictions, and all measures to control cardiac risk factors were advised. Throughout a 6-year follow-up, the diabetes mellitus remained well controlled, the ECG remained unchanged, and no clinical or ECG signs of neuropathy became apparent. The importance of diabetes mellitus, both type 1 and type 2, in the epidemiology of cardiovascular diseases cannot be overemphasized. About one third of acute myocardial infarction patients have diabetes mellitus, the prevalence of which is steadily increasing: In the 1960s, there were 2 million Americans with diabetes mellitus; in the year 2000, their number was 15 million. Statistics have shown that the decrease in cardiac mortality in persons with diabetes mellitus is lagging behind that of the general population.1 Early diagnosis of diabetes mellitus is crucial. Fibrotic changes, especially in the basal area of the left ventricle, have frequently been observed in diabetic patients, even when cardiac involvement is clinically not yet evident. An example of the ECG tracing in a diabetic patient with no apparent heart disease is given in Figure 1. Figure 1. …