Search results
Results From The WOW.Com Content Network
The sinoatrial node (also known as the sinuatrial node, SA node or sinus node) is an oval shaped region of special cardiac muscle in the upper back wall of the right atrium made up of cells known as pacemaker cells. The sinus node is approximately 15 mm long, 3 mm wide, and 1 mm thick, located directly below and to the side of the superior vena ...
The sinoatrial node (SA node) is the primary pacemaker of the heart. It is a region of cardiac muscle on the wall of the upper right atrium near to the superior vena cava entrance. The cells that make up the SA node are specialized cardiomyocytes known as pacemaker cells that can spontaneously generate cardiac action potentials.
The sinoatrial node is located in the superior part of the crista terminalis at the junction of the right atrium, and superior vena cava. [2]: ...
An impulse (action potential) that originates from the SA node at a relative rate of 60–100 bpm is known as a normal sinus rhythm. If SA nodal impulses occur at a rate less than 60 bpm, the heart rhythm is known as sinus bradycardia. If SA nodal impulses occur at a rate exceeding 100 bpm, the consequent rapid heart rate is sinus tachycardia ...
The origin of the sinoatrial node artery is not related to coronary artery dominance, which means the side (right or left) that provides the circulation to the back of the heart. In contrast, the atrioventricular nodal branch, that is the artery that brings blood to the atrioventricular node, depends on coronary artery dominance. [citation needed]
The sinoatrial node (SA node) is located in the posterior aspect of the right atrium, next to the superior vena cava. This is a group of pacemaker cells which spontaneously depolarize to create an action potential.
SA node: 60–100 bpm; Atrioventricular node(AVN): 40–60 bpm; Purkinje fibres: 20–40 bpm; The potentials will normally travel in order SA node → Atrioventricular node → Purkinje fibres Normally, all the foci will end up firing at the SA node rate, not their intrinsic rate in a phenomenon known as overdrive-suppression.
Under normal conditions, the heart's sinoatrial node (SA node) determines the rate by which the organ beats – in other words, it is the heart's "pacemaker". The electrical activity of sinus rhythm originates in the sinoatrial node and depolarizes the atria.