MECHANISM OF SYNCOPE AND ACTION OF DRUGS IN COMPLETE HEART BLOCK

The syncopal attacks of complete heart block may be due either to ventricular standstill or to ventricular acceleration including fibrillation. As treatment may be harmful unless the underlying mechanism in each case is determined, it is important to apply the available methods for differentiation. Epinephrine and certain related compounds (sympathomimetic amines) are the only effective substances in the therapy of ventricular arrest. Isopropyl nor-epinephrine is a most potent drug in the prevention and treatment of ventricular arrest and has the advantage that it does not dispose to fibrillation. Quinidine is unreliable and probably hazardous in the control of ventricular fibrillation in heart block as it appears to precipitate this arrhythmia.Preliminary observations indicate that ectopic ventricular rhythms are also induced by procaine amide in complete heart block.Isuprel(R) may be of value in the therapy of ventricular acceleration, by preventing the ventricular arrest which frequently follows the initial acceleration.

THE EFFECT OF NEW DRUGS ON THE RHYTHMIC FUNCTION OF THE HEART

Epinephrine and related drugs (sympathomimetic amines) are the only compounds which effectively increase the rhythmic function of the heart. Effects of two new non-pressor sympathomimetic compounds were observed. One of these compounds, the isopropyl homologue of epinephrine, was found to be about five times more active than epinephrine.From clinical observations on the action of a new cardiac depressant drug, alpha-fagarine, it was concluded that the drug is very effective but that toxic reactions are unpredictable. The potency of alpha-fagarine and related compounds suggests the possible development of chemically related non-toxic drugs having an effective cardiac depressant action.

The Retention of the Wheat Vitamins in Flour and Bread, a Problem of National Importance

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