The Electrocardiographic Effects of Hypocalcemia Induced in Normal Subjects with Edathamil Disodium

In the past, it has not been possible to study the electrocardiographic effects of hypocalcemia in normal subjects. Edathamil disodium is a powerful chelating agent with a strong affinity for ionic calcium when given intravenously. This agent was used to produce hypocalcemia in normal subjects so that electrocardiographic effects could be studied. The major changes produced in the electrocardiogram with the induction of hypocalcemia were shortening of the R-R interval, prolongation of the RS-T and Q-T intervals, all of which were proportional to the degree of hypocalcemia. No change in the spatial P, QRS and T vectors, no T wave flattening or inversion and no elevation or depression of the RS-T segment appeared with hypocalcemia.