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PubMed · 4499916

Experimental His bundle escape rhythms.

T Pérez-Medina·T Garcia-Barreto·A Hernández-Cañero
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Abstract

With the purpose of studying the interactions between sino-atrial (S-A) node and His bundle escape rhythms (HBER), negative chronotropic agents (verapamil, manganese and droperidol) were directly injected in the canine S-A node through its cannulated and autoperfused artery. HBER followed S-A node depression assessed by His bundle electrograms. A well established correlation was found between HBER and S-A node initial rate. His bundle recovery time following an atrial overdrive was 50 times larger than the S-A node recovery time. HBER was found to be more sensitive to sympathetic blockade than to vagal influences. It is concluded that 1) recovery time following overdrive stimulation is a valid index reflecting sinus nodal function; 2) HBER commonly results from selective depression of the S-A node not only depends on rate but also on overdrive suppression; 4) HBER is more sensitive to sympatheticmodulation.

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AnimalsBundle of HisCardiac Pacing, ArtificialDogsDroperidolHeart Conduction SystemManganeseSinoatrial NodeVerapamilJournal Article

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T Pérez-Medina, T Garcia-Barreto, A Hernández-Cañero. 1972. Experimental His bundle escape rhythms.. https://pubmed.ncbi.nlm.nih.gov/4499916/

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