Hypoglycemia is associated with alterations of the ECG, a phenomenon which might be
used for the development of a hypoglycemia detection device. We investigated the reproducibility
and magnitude of ECG alterations during insulin-induced hypoglycemia in nine healthy
volunteers. The subjects were studied twice with an identical study protocol on two
different study days. During hypoglycemia frequent ECG recordings were done with a
conventional 12 lead ECG. S.c. injection of 0.15 U/kg of regular insulin induced a
fourfold increase in insulinemia on both study days as well as a mean decline in blood
glucose by 1.6 mmol/l to a minimum of 2.8 mmol/l within 60 min after injection. Blood
potassium levels declined by a mean of 0.25 mmol/l to minimal values of 3.69 mmol/l.
On both study days, a progressive flattening of the T-waves was observed during the
experiments. R-waves remained constant leading to an increase in RT ratios by at least
50% in comparison to baseline values. These changes were most pronounced in leads
I, V3, V5 and V6. The magnitude and reproducibility of the observed ECG changes during
hypoglycemia may allow the development of a hypoglycemia detection device.
Key words
Insulin Therapy - Hypoglycemia - Electrocardiogram - Pottassium
