Use of a Calcium Chelating Agent(NaEDTA) in Cardiac Arrhythmias

Abstract

The interrelated effects of digitalis and various cations on cardiac rhythmicity are the subject of much recent interest. This paper presents additional data on this subject that carry important therapeutic implications. The chelating agent, disodium ethylene diamine tetra acetate (NaEDTA), has been used intravenously in 14 instances of supraventricular and ventricular arrhythmia. Digitalis had been administered previously in 13 instances, and various degrees of digitalization were encountered. This report summarizes our experience with NaEDTA as a test of the degree of digitalis therapy and as treatment of the arrhythmias observed.

Effects of Calcium Chelation on Digitalis-Induced Cardiac Arrhythmias

“…body weight of disodium EDTA were given intravenously at five-minute intervals. Regular serum calciumr estimations were not carried out in this study, because (1) it has already been reliably established that EDTA is most effective in producing a rapid, though transient hypocalcdemia (Popovici et al, 1950;Bessman and Doorenbos, 1957;Surawicz, 1960); (2) in the context of the present experiments the prolongation of the Q-T interval in the electrocardiogram can be regarded as a reliable sign of the existence of a hypocalcemic state (Barker, Johnston, and Wilson, 1937;Somerville, 1951); and (3) there is evidence of a poor quantitative relation between the degree of hypocalcwmia and the clinical response (Cohen et al, 1959;Surawicz et al, 1959).…”

“…Eliot and Blount (1961) also found EDTA much more reliable in digitalis-induced cardiac arrhythmias than in those of other origin. On the other hand, several reports show that EDTA is equally effective in abolishing ectopic beats not due to digitalis (Cohen et al, 1959;Surawicz et al, 1959;Surawicz, 1960;Soffer et al, 1961;Corday et al, 1962).…”

Diagnostic de l’intoxication digitalique et son traitement

“…Parmi d'autres thérapeutiques des troubles rythmiques graves de l'intoxication digitalique, les médicaments suivants sont proposés, qui ont chacun des promoteurs convaincus : a) Le Vcrsenate de sodium (Na2EDTA), chélateur du calcium, extrêmement actif, mais auquel on reproche un effet transitoire et des ennuis secondaires prohibitifs à la longue, voire dangereux [135,39,59,62,128,127,22,3]. b) Le Sulfate de magnésie, solution à 20 % : 20 ml i.v.…”

The Use of Digitalis in Children

“…Conversely a reduction in serum calcium effected by administering sodium versenate or some other chelating agent reduces digitalis toxicity rapidly. 15 It might be wise to avoid the administration of large doses of calcium intravenously to patients who have been digitalized, and to administer digitalis only with extreme caution to persons who necessarily are also receiving calcium. 16 The cardiac glycosides are able to increase the entry of calcium into the contracting heart, and the contractions induced by the glycosides may be due to the altered handling of calcium by cardiac cellsY It is interesting that large doses of calcium alone may evoke arrhythmias similar to those resulting from digitalis intoxication.…”

“…The sodium salt of EDT A, 600 m g. given intravenously, may prove effective in treating cardiac arrhythmias initiated by digitalis. 15 Procaine amide ( PRONESTYL ®) , 7 mg. per pound of body weight given orally every six hours, or quinidine sulfate, 3 gr. per pound every three hours, may also he used to suppress some of the ventricular ar-604 rhythmias and tachycardias associated with digitalis therapy.…”