[Transesophageal cardiac pacemakers].

Based on over 10-year experience in developing, clinically testing, and using a great deal of different models of transesophageal pacemakers, the paper presents a concept of a present-day pacemaker. It reviews the production and experimental models of these apparatuses currently available in Russia.

[Comparative assessment of the diagnostic value of intracardiac and transesophageal electrophysiological examination of patients with reciprocal atrioventricular tachycardia caused by additional atrioventricular junctions].

Thirty patients with frequent attacks of supraventricular tachycardia were investigated, and a reciprocal paroxysmal atrioventricular tachycardia due to additional atrioventricular junctions was diagnosed in 16 of those. Heart rhythm disorders were rooted in the apparent Wolff-Parkinson-White syndrome in 8 patients, and in its latent variety in another 8. A comparative assessment of diagnostic potentials of esophageal and intracardiac electrophysiologic investigation demonstrated the latter to be an effective method for provoking reciprocal atrioventricular tachycardias and allow a reliable assessment of basic antegrade refractory periods and intervals of the heart's conductive system, including the effective refractory period of Kent's bundle, in patients with additional atrioventricular junctions.

[Serial testing of anti-arrhythmia preparations using the intracardiac electrophysiological study of patients with reciprocal paroxysmal tachycardias].

Diagnostic investigation of 36 patients with reciprocal paroxysmal tachycardias, using intracardiac electrophysiologic tests, revealed supraventricular paroxysmal tachycardia in 29 patients, and ventricular paroxysmal tachycardia in 7. Serial trials of antiarrhythmic drugs in acute experiments with simultaneous electrophysiologic studies made possible efficient medication in 80% of the patients. A high correlation was demonstrated between the results of acute antiarrhythmic drug tests and subsequent long-term treatment.

[Concept of the polyfascicular structure of the atrioventricular junction in patients with reciprocal paroxysmal nodal tachycardias].

Intracardiac electrophysiologic studies were carried out in 41 patients with paroxysmal supraventricular tachycardias. Reciprocal atrioventricular tachycardia due to dissociated conduction through the atrioventricular junction was diagnosed in 29 patients. Electrophysiologic data suggested trifascicular atrioventricular conduction in 4 patients, and quadrifascicular conduction in 2.

[Latent Wolff-Parkinson-White syndrome as the electrophysiological and morphological basis of supraventricular tachycardia].

The concealed Wolff-Parkinson-White (WPW) syndrome, the electrophysiologic and morphologic basis of cardiac arrhythmias, was shown to be a cause of the attacks of supraventricular tachycardia. The latter is rooted in the concealed WPW syndrome in about 30% of patients showing no electrocardiographic signs of pre-excitation. Electrophysiologic criteria of the diagnosis of supraventricular tachycardias due to the concealed WPW syndrome are listed.