[Skip to Content]
Access to paid content on this site is currently suspended due to excessive activity being detected from your IP address 54.161.216.242. Please contact the publisher to request reinstatement.
[Skip to Content Landing]
Article
November 1920

CHRONIC BRADYCARDIA

Author Affiliations

ROCHESTER, MINN.

From Section on Medicine, Mayo Clinic.

Arch Intern Med (Chic). 1920;26(5):630-646. doi:10.1001/archinte.1920.00100050123009
Abstract

Chronic bradycardia and its attendant cardiovascular phenomena present innumerable interesting problems. Many causes are ascribed to the slow heart; this results in a cumbersome and confusing classification. It may not be amiss briefly to summarize the causes generally accepted:

  1. Chemical Substances.—The inhibitory action of the following substances is well known and warrants no discussion here: (a) The neutral non-nitrogenous glucosids and resins; the active principles of digitalis, squills, strophanthus and apocynum; (b) alkaloids such as erythrophlein, veratrin and aconitin; (c) biliary constituents, and (d) inorganic substances, such as barium salts and hydrates.1

  2. Stimulation of the Cardiac Vagus.—Stimulation may be peripheral or central.

  3. Myocardial Disease.—Involvement of the myocardium by disease (a) associated with lesions of the auriculoventricular bundle (complete heart block and delayed impulse transmission), and (b) without involvement of the bundle.

  4. Certain physiologic reactions without cardiac damage.

  5. The early and late stages of asphyxia.2

PHYSIOLOGY OF CHRONIC BRADYCARDIA 

First Page Preview View Large
First page PDF preview
First page PDF preview
×