Clinical Electrophysiology of the Cardiac Conduction System

Abstract

Recording the human cardiac biological signal from the body surface, the electrocardiogram (ECG) has been used for at least seven decades in the diagnosis and management of cardiac disorders in infants and children, primarily by examining for criteria of hypertrophy or dilatation imposed by congenital cardiac malformations, rheumatic heart disease, or other acquired heart conditions. Other than the ECG findings of congenital heart block and supraventricular tachycardia, originally called paroxysmal atrial tachycardia, little attention was directed to either the clinical or fundamental electrophysiology underlining arrhythmias in the young. Since the recording of the His bundle electrogram, first in the dog in 1957, then in the human in the operating room in 1959, and by means of the transcatheter technique in adults in 1969 and children in 1971, there has been a rapid advancement in the understanding of the clinical disorders of impulse formation and propagation. This advance has been both contemporary with and driven by major technological improvements including catheter design, computer-assisted recording, analysis and archival systems, and innovative transcatheter therapy. Because these major advances have evolved from adult populations, the application to young patients calls for special considerations.