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  2. Sinoatrial node - Wikipedia

    en.wikipedia.org/wiki/Sinoatrial_node

    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 ...

  3. Atrioventricular node - Wikipedia

    en.wikipedia.org/wiki/Atrioventricular_node

    The atrioventricular node or AV node electrically connects the heart's atria and ventricles to coordinate beating in the top of the heart; it is part of the electrical conduction system of the heart. [1] The AV node lies at the lower back section of the interatrial septum near the opening of the coronary sinus, and conducts the normal ...

  4. Koch's triangle - Wikipedia

    en.wikipedia.org/wiki/Koch's_triangle

    It is an anatomical area located at the base of the right atrium, and its boundaries are the coronary sinus orifice, tendon of Todaro, and the septal leaflet of the right atrioventricular valve (also known as the tricuspid valve). [2] It is anatomically significant because the atrioventricular node is located at the apex of the triangle. The ...

  5. Cardiac conduction system - Wikipedia

    en.wikipedia.org/wiki/Cardiac_conduction_system

    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 ...

  6. Cardiac pacemaker - Wikipedia

    en.wikipedia.org/wiki/Cardiac_pacemaker

    Impulses from the sinus node reach the atrioventricular node which acts as the secondary pacemaker. The cells of the AV node normally discharge at about 40–60 beats per minute, and are called the secondary pacemaker. Further down the electrical conducting system of the heart is the Bundle of His.

  7. Heart - Wikipedia

    en.wikipedia.org/wiki/Heart

    The normal rhythmical heart beat, called sinus rhythm, is established by the heart's own pacemaker, the sinoatrial node (also known as the sinus node or the SA node). Here an electrical signal is created that travels through the heart, causing the heart muscle to contract.

  8. Sinoatrial nodal artery - Wikipedia

    en.wikipedia.org/wiki/Sinoatrial_nodal_artery

    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]

  9. Sinus rhythm - Wikipedia

    en.wikipedia.org/wiki/Sinus_rhythm

    A sinus rhythm is any cardiac rhythm in which depolarisation of the cardiac muscle begins at the sinus node. [1] It is necessary, but not sufficient, for normal electrical activity within the heart. [2] On the electrocardiogram (ECG), a sinus rhythm is characterised by the presence of P waves that are normal in morphology. [2]