Thyroid hormone-mediated positive cardiotropic effects are differently regulated between the atria and ventricles. This regulation is, at least in part, dependent on sarcoplasmic reticulum (SR) proteins. Sarcolipin, a homologue of phospholamban, has been recently identified as an atrium-specific SR protein. The expression of sarcolipin mRNA was significantly decreased in the atria of mice with ...

1. The pharmacological characteristics of adrenoceptors at different temperatures were assessed on the basis of the effects of various alpha- and beta-adrenoceptor agonists and antagonists on electrically-driven left atria and spontaneously-beating pairs of atria from rats. 2. Phenoxybenzamine (Pbz) potentiated inotropic responses of left atria to noradrenaline (NA) at 31 degrees C, produced si...

We described here a patient who presented with symptoms of heart failure who was found to have severe bilateral impairment of atrioventricular inflow. Primary cardiac lymphoma (PCL) with extensive involvement of the two atria, pericardium and myocardium is an extremely rare tumor in immunocompetent patients. We report here a case of PCL in an immunocompetent patient with involvement of both atr...

The atrioventricular (AV) node is the only conduction pathway between the atria and ventricles, it is located at the base of the right atrium. The conduction through the atrioventricular node is slow to allow the atria to pump blood into the ventricles before they contract. It also acts as a backup pacemaker, in case the sinoatrial node fails and limits the number of action potentials conducted...

Addition of specific antigen to the isolated atria of sensitized guinea pigs and of histamine to those of nonsensitized animals resulted in an increase of both frequency and amplitude of contraction and in the appearance of rhythmic activity in the isolated left atrium. On a quantitative basis the anaphylactic response looks like the effects of histamine in concentrations between 10~ and 10~ mM...

The conduction disturbances in atrioventricular block are well known from numerous electro-cardiographic studies, but the effect on the heart work, especially on the individual chambers, could not be recorded before the introduction of visualization of the heart chambers by angio-cardiography. Rapid biplane angiocardiography with simultaneous electrocardiographic yields information on cardiac d...

In the normal heart, an insulating barrier separates the atria and ventricles. The only way in which electrical impulses can cross this barrier is via the atrioventricular (AV) node, which delays impulse conduction to ensure the forward flow of the blood. However, in some individuals, additional muscular bundles (accessory pathways) allow rapid conduction of electrical impulses from the atria t...

Approximately 10% of congenital heart diseases (CHDs) include Tetralogy Fallot (TOF). Fortunately, due to advanced surgical techniques, most patients survive until adulthood. However, these require frequent monitoring for postoperative complications leading hemodynamic alterations. Turbulent kinetic energy (TKE), as derived from 4D-flow magnetic resonance imaging (4D-flow MRI), has been used ch...