Primary care aspects of atrial fibrillation

Abstract

A better understanding of the pathophysiologic mechanisms that determine the random pattem of ventricular rhythm may assist the primary care physician in treating and guiding atrial fibrillation patients. These mechanisms also form the basis for our understanding of drug action and effect on ventricular rate and rhythm. Atrial fibrillation is more likely to occur in larger, older mammalian hearts, and is diagnosed mainly by the occurrence of random ventricular rhythms, which may be studied by means of histograms and serial autocorrelograms. Digitalis, still widely used in the treatment of atrial fibrillation, affects the atrioventricular node by increasing the functional refractory period and by enhancing its capacity for concealed conduction, thus limiting the number of atrial impulses allowed to influence the ventricular rate and increasing the number and duration of RR intervals.