[Use of differential methods for analyzing electrocardiograms in the diagnosis of supraventricular arrhythmia].

Differential-gain ECG (DG-ECG) recordings were made to investigate the mechanism of tachyarrhythmias. The study comprised experimental and clinical series. Experimental findings demonstrated two types (local and circulatory) of vulnerability manifested during induced tachyarrhythmia.

[Relation between intra-atrial conduction and disorders of sinoatrial, atrioventricular and intraventricular conduction (according to selectively intensified ECG findings)].

The differentially intensified ECG was recorded from the chest surface to determine the intraatrial conductivity in patients with chronic coronary heart disease. The parameters of the differentially intensified ECG were compared with the indices of intraatrial conductivity on the intracavitary electrogram. Disorders of intraatrial conductivity were also compared with impairments of conductivity in other sites of the conductivity system of the heart.