Four hearts are described in which the right atrioventricular valve, draining a morphologically right atrium, straddled and overrode a septum between a right-sided chamber of left ventricular morphology and a left-sided chamber of right ventricular morphology. The degree of override varied between the straddling valve and was committed by 20-45% to the morphologically right ventricle. The ventr...

AIM To compare ventricular rate responsive (VVIR) pacing with dual chamber rate responsive (DDDR) pacing and antiarrhythmic drugs for the treatment of patients with persistent atrial fibrillation after atrioventricular node ablation. METHODS One hundred two patients with persistent atrial fibrillation eligible for the atrioventricular node ablation were randomly assigned to the therapy with e...

Bradycardia is a common finding in patients with obstructive sleep apnea and might be pronounced in heart failure patients. The aim of the present study was to determine the relationship between nocturnal hypoxemia, apnea-hypopnea index, and electrophysiological parameters of sinus node and atrioventricular conduction properties. Electrophysiological studies were performed in 12 patients with h...

A genetic predisposition associated with HLA B27 for developing complete heart block with or without clinical or radiological signs of associated rheumatic disease has recently been found. In this electrophysiological study of 12 patients with spontaneous complete heart block and HLA B27 associated disease, of whom eight had ankylosing spondylitis, 10 had suprahisian second or third degree atri...

OBJECTIVE In the heart, there are multiple supraventricular pacemakers involved in normal pacemaking as well as arrhythmias and the objective was to determine the distribution of HCN4 (major isoform underlying the pacemaker current, I(f)) in the atria. METHODS In the atria of the rat, the localisation of HCN4 and connexins was determined using immunohistochemistry, and electrical activity was...

OBJECTIVE The molecular mechanisms that regulate the formation of the conduction system are poorly understood. We studied the developmental expression pattern and functional aspects of the T-box transcription factor Tbx3, a novel marker for the murine central conduction system (CCS). METHODS The patterns of expression of Tbx3, and of Cx40, Cx43, and Nppa, which are markers for atrial and vent...