[The structural-functional status of the myocardium and the electrophysiological indices in patients with atrial fibrillation]. / Strukturno-funktsional'noe sostoianie miokarda i élektrofiziologicheskie pokazateli u bol'nykh s fibrilliatsiei predserdii.

A study is presented of 100 male patients with paroxysmal forms of atrial fibrillation (age: from 16 to 66 years). It is concluded that the determinant substrate of formation of atrial fibrillation is not limited to functional, electrophysiologic and morphologic state of the atria but encompasses the entire conduction system and structure of the myocardium both on the atrial and ventricular level. The frequency of paroxysms of atrial fibrillation and their severity are in direct dependence not only on the electrophysiological values but also on the degree of structural changes of the myocardium.

[The current concepts of the effect of cardiac glycosides on sinus node function and atrioventricular conductivity]. / Sovremennye predstavleniia o vliianii serdechnykh glikozidov na funktsiiu sinusovogo uzla i atrioventrikuliarnuiu provodimost'.

The clinical aspects of the influence of cardiac glycosides on the sinus node and atrioventricular junction in health and dysfunction are reviewed. It has been shown that digitalis drugs do not produce any effect on sinus node automatism including that in dysfunction. Cardiac glycosides suppress enhanced atrioventricular conduction and do not affect it provided it remains within normal. The mechanisms by which cardiac glycosides may act are discussed: extracardiac, cholinomimetic (in the acute test and direct one) and influencing heart conduction components (when used continuously).

[Ambulatory transesophageal cardiac electrostimulation and daily Holter cardiac monitoring of patients with a heart rhythm disorder]. / Ambulatornaia chrespishchevodnaia élektrokardiostimuliatsiia i sutochnoe kholterovskoe kardiomonitorirovanie bol'nykh s narusheniem serdechnogo ritma.

Sixty-eight patients with different disorders of the cardiac rhythm were examined in ambulatory conditions. The complex of noninvasive examinations included: echocardiography, Holter monitoring, bicycle ergometry [correction of veloergometry] and transesophageal cardiostimulation with performance of diagnostic and pharmacological tests. The obtained data permitted to evaluate disorders of automatism and conduction at different levels of the cardiac conduction system, to identify paroxysmal tachyarrhythmia and realize selection of antiarrhythmic agents.

[Effect of digoxin on sinoatrial node automatism and atrio-ventricular conductivity in patients with a paroxysmal form of atrial fibrillation]. / Vliianie digoksina na funktsiiu avtomatizma sinusovogo uzla i atrioventrikuliarnuiu provodimos't u bo'lnykhs paroksizma'l- noi formoi fibrilliatsii predserdii.

Digoxin was studied for its effects on the function of sinus nodal automatism and atrioventricular conduction in an acute experiment and during a course therapy. Digoxin was shown to exert substantial effects on the sinus node with its retained function and dysfunction. When digoxin was given in a daily dose of 0.375 mg, there was an increase in sinoatrial conduction time. When the drug was administered in a single dose of 0.4 mg, there was no substantial change in the atrioventricular conduction. During its course therapy, digoxin failed to produce antirecurrent antiarrhythmic effects.