SUMMARY Ventriculo-atrial conduction and the reentry phenomenon was studied during right ventricular and bundle of His pacing in the intact dog heart. Bipolar electrogram recordings were obtained from the sinus node, Bachman's bundle, the right and left atria, the bundle of His, and the ventricle. Retrograde conduction resulted in a specific change in the sequence of atrial activation. The reco...

• It was reported recently that cardiac arrhythmia induced in cyclopropane anesthetized dogs by infusion of epinephrine could be converted to normal sinus rhythm by vagal stimulation. The termination of multifocal ventricular tachycardia is interesting because it is not readily apparent how vagal influence, presumably limited to the A-V node or upper bundle of His, alters arrhythmia predominant...

A premature ventricular contraction (PVC) is relatively a common event where the heartbeat is initiated by the other pathway rather than by the Sinoatrial node, the normal heartbeat initiator. Determining PVC foci is important for ablation procedure and it can help in pre-procedural planning and potentially may improve ablation outcome. In this study, 12-lead Electrocardiogram (ECG) of 87 patie...

Background: It has not been yet developed a ost suitable method to treat right ventricular failure due to pulmonar artery hypertention resulted from ventricular arrhythia. Though some case reports about patients ready to heart transplant using left assist device or biventral assist device as bridge have been published in Journals, but nocase concerning application of centrifugal pump for treatm...

The identification of nearly a dozen ion channel genes involved in the genesis of human atrial and ventricular arrhythmias has been critical for the diagnosis and treatment of fatal cardiovascular diseases. In contrast, very little is known about the genetic and molecular mechanisms underlying human sinus node dysfunction (SND). Here, we report a genetic and molecular mechanism for human SND. W...

OPERATION of a nervous mechanism in the genesis of cardiac arrhythmias secondary to the injection of calcium chloride was suggested by the observation that electrical sympathetic stimulation consistently induced ventricular arrhythmias only when calcium chloride was given simultaneously. Insight into the problem was obtained when sympatholytic and other autonomic blocking drugs were reported to...

BackgroundIncreased metabolic rate of hyperglycemia in gestational diabetes causes macrosomia, which can also affect the fetal heart. The thickness of the walls of the heart and its function in women with gestational diabetes mellitus (GDM) can change over time before treatment. We aimed to evaluate fetal cardiac structure in terms of ventricular wall thickness and its function in women w...

In complete heart block, absolute independence between atrial and ventricular activity does not always occur. Several mechanisms may be postulated to explain this phenomenon. One is incomplete atrio-ventricular block; another is atrio-ventricular synchronization and accrochage (Marriott, 1956; Schubart, Marriott, and Gorten, 1958; Ettinger, 1965). A third possibility rarely considered is unidir...

direct regenerations by using mature cotyledonary node as a explants has been shown to be time-saving and convenient strategy for micropropagation of soybean. so we have evaluated regeneration protocol through single shoot using cotyledonary node as a rapid and efficient protocol for two soybean cultivars and one mutant line. cotyledonary nodes explants obtained from 7-days-old in vitro seedlin...