[Systolic and diastolic load of right heart and right bundle block]

Analysing the Ecg and VCG of 818 subjects, healthy or with different congenital and acquired cardiopaties, the frequency of right bundle branch block (RBBB) is established to decrease with the increase in age of children, and is observed to be 8.9% in healthy adults. The right bundle block is observed in 82.5% of the patients with atrial septal defect and quite often in patients with right ventricle tension loading, gradually decreasing with the level of the left ventricle loading, as well as with the development of extreme right ventricle hypertrophy. Out of 50 experiments with dogs with acute and chronic right heart tension loading it is evident that the number of certain and marginal (uncertain) cases with RBBB steadily increases. At the same time this increase cannot be connected with the type of loading, in dogs in which dilatation of the right ventricle is presented as well as in others with light or marked hypertrophy. Besides, under the same conditions and durations of loading some hearts exhibit RBBB, while others do not. What has been stated before gives enough grounds to accept that RBBB in healthy subjects, as well as in patients with congenital and acquired cardiopaties manifests the electromotive tension (EMT) of persistent from foetal and children-age more pronounced physiological hypertrophy (as normal variant) of the basal part of the right ventricle. Whether the picture of RBBB is retained, pronounced or disappears is determined by the correlation between the quantity and the time-manifestation of EMT of the left ventricle and of the corps part of the right ventricle.