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B Befeler

Publications and source records attributed to B Befeler.

85 records · Page 5Linked to original sources
PubMedDate not supplied

His bundle recordings: their contribution to the understanding of human electrophysiology.

His bundle electrocardiography has increased our understanding of the electrophysiology of the conducting system and has confirmed a number concepts which evolved from analysis of surface electrocardiograms. Electrophysiologic evaluation of conduction disease in the cardiac catheterization laboratory has become an accepted diagnostic procedure in determining the site of atrioventricular and ventriculo-atrial block as well as in the evaluation of patients with pre-excitation resulting from conduction through Kent and James bundles. Recent reports suggest that His bundle electrograms may prove to be of clinical and therapeutic significance in determining the site of re-entry in patients with PSVT as well as in determining the short-term prognosis of patients with acute myocardial infarction complicated by incomplete bundle branch block. As our knowledge and understanding of the basic mechanisms, specific therapy, and prognosis of cardiac arrhythmias are expanded, the data derived from His bundle electrocardiography will become more useful in the clinical practice of cardiology.

Arrhythmia, Sinus↗
PubMedDate not supplied

[Gap phenomenon in the bundle of his conduction].

His bundle electrograms recorded during atrial stimulation with the extrastimulus technique permitted the analysis of the so called gaps in bundle branch conduction. Three different types of gaps were identified each with a distinct electrophysiological mechanism. In type I gap a CLBBB pattern disappeared at shorter coupling (A1-A2) intervals because the more premature impulses encountered a greater degree of the delay at the A-V node therefore reaching the left bundle branch after its effective refractory period had ended. During this part of the cycle the H1-H2 were longer and H2-V2 intervals shorter than when CRBBB was present. In type II gap a CRBBB pattern disappeared at shorter coupling intervals because the premature impulses met a greater delay in the proximal portions of the His-Purkinje system. In consequence, they arrived at the right bundle branch when its effective refractory period had expired. When this occurred the H1-H2 interval were shorter and the H2-V2 longer than those at which CRBBB had been present. The patient with type III gap had CLBBB. A-V conduction was possible through the right bundle branch very late in the cycle. However, it could not occur at shorter coupling intervals finally reappearing at even shorter coupling intervals. True supernormal conduction or vagal pulsatile discharges could have been present. Yet, we favor, as the most likely possibility, the existence of 2:1 phase 4 block with latent or abortive escapes not recorded in the surface leads.

Bundle of His↗
PubMedDate not supplied

[Value of interacardiac recordings in the evaluation of positive QRS in V1 provoked by stimulation of the right ventricle].

The analysis of the common bundle and of the ventrical filtered electrograms has incrased our knowledge of the intraventricular conduction following the simulation of the PVS as well as the different types or reciprocating that can be produced by premature beats. 2. The positive QRS complexes in V1 produced from PVD by St2 can be explained as a greater degree of incomplete recuperation of the right ventricular wall than in the interventricular septum. In contrast with what happened in the basal beats, where the front took longer to reach the TSVD than the VI. 3. The refractarines of the transitional tissues that serve as the phisiological banier was longer than the banal myocardium. The intraventricular propagation, and therefore the morphology and direction of QRS, depended of this one; while the moment of arrival of activation retrogradly to the common bundle was conditioned by the transitional tissues. 4. Episodes of ventricular taquicardies with QRS positive complexes in V1 can be due to a re-entry throught the bundle branches or in (or around) an area that has been recently injured.

Bundle of His↗