Electrical coupling between heart muscle cells is mediated by specialised regions of sarcolemmal interaction termed gap junctions. In previous work, we have demonstrated that connexin42, a recently identified gap-junctional protein, is present in the specialised conduction tissues of the avian heart. In the present study, the spatial distribution of the mammalian homologue of this protein, conn...

A 27-year-old man with primary oxalosis and extensive visceral involvement was maintained on long-term chronic hemodialysis. He had an episode of presyncope associated with electrocardiographic findings of an erratic atrial rhythm, atrioventricular dissociation due to an accelerated junctional rhythm and right bundle branch block. Electrophysiologic studies showed irregular atrial depolarizatio...

The unexpected findings of atrioventricular block or delay in the His bundle and proximal branches are described in a 51-year-old man with acute inferior myocardial infarction with narrow QRS complexes. With the information from the His bundle electrogram, the site of atrioventricular block is precisely localized.

Four cases of complete right bundle-branch block and one case of atrioventricular heart block, all occurring within three generations of the same family, are described. The 4 patients with bundle-branch block had no symptoms, whereas the patient with atrioventricular heart block suffered Adams-Stokes attacks from the age of 13 and died at 47 years of age. A 33-year-old man with bundle-branch bl...

A single suction electrode catheter was used for His bundle electrogram recording. His bundle pacing, and low-energy (20 or 30 J) His bundle ablation in seven dogs. The suction electrode catheter was actively fixed to the atrial endocardium at the His bundle level. Electrophysiologic studies were performed in the control state, immediately after, and late (greater than 40 days) after His bundle...

or bundle of His. Blockage of both the right and left bundle branches would be tantamount to block at these locations. This is the well-established concept of bilateral bundle-branch block.1-3 It highlights a hazard inherent in catheterization of the ventricle opposite that which is already the site of bundle-branch block. Since the advent of cardiac catheterization, numerous reports have been ...

An 18-year-old man whose sister has classic Kartagener's syndrome was found to have sinusitis, bronchiectasis, and corrected transposition with normal visceral situs. Congenital complete heart block was secondary to absence of conducting-system pathways between a small posterior atrioventricular node and the transposed His bundle and bundle branches. No anterior atrioventricular node was presen...

BACKGROUND Little is known about the distribution of gap junctions and ion channels in the atrioventricular node, even though the physiology and pathology of the atrioventricular node is ultimately dependent on them. METHODS AND RESULTS The abundance of 30 transcripts for markers, gap junctions, ion channels, and Ca(2+)-handling proteins in different regions of the rabbit atrioventricular nod...