ECG and MCG Studies on the His-Purkinje Activity in a Case of Congenital Heart Block

Abstract

Non-invasive detection of the His-Purkinje (HP) activity could be useful in clinical practice, e.g. in determining the actual site of atrio-ventricular (A-V) block or in evaluating the effect of anti-arrhythmic drug therapy on heart conduction system. The HP activity from body surface was first measured electrically by Berbari et al. (1978). First magnetic study of the HP conduction system was reported by Farrell et al. (1980). The HP activity was described as a ramp like structure in the P-Q interval. Fenici et al. (1985) reported magnetic His-Purkinje studies with invasive ECG reference. In normal subjects the overlapping atrial activity causes serious interference with the HP-signal. To avoid this overlapping, Mäkijärvi et al. (1985) investigated patients with total A-V block. However, in these studies the accurate timing was difficult because intracardial reference ECG was not available.