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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

    Isolated heart conduction system showing atrioventricular node. The AV node receives two inputs from the right atrium: posteriorly, via the crista terminalis, and anteriorly, via the interatrial septum. [8] Contraction of heart muscle cells requires depolarization and repolarization of their cell membranes. Movement of ions across cell ...

  4. Anomalous aortic origin of a coronary artery - Wikipedia

    en.wikipedia.org/wiki/Anomalous_aortic_origin_of...

    The AAOCA is a rare birth defect in the heart that occurs when a coronary artery arises from the wrong location on the main blood vessel, the aorta. [ citation needed ] Children and young adults with these defects can die suddenly, especially during or just after exercise.

  5. Cardiac conduction system - Wikipedia

    en.wikipedia.org/wiki/Cardiac_conduction_system

    The delay in the AV node forms much of the PR segment on the ECG, and part of atrial repolarization can be represented by the PR segment. The distal portion of the AV node is known as the bundle of His. [8] The bundle of His splits into two branches in the interventricular septum: the left bundle branch and the right bundle branch.

  6. Cardiac cycle - Wikipedia

    en.wikipedia.org/wiki/Cardiac_cycle

    The rhythmic sequence (or sinus rhythm) of this signaling across the heart is coordinated by two groups of specialized cells, the sinoatrial (SA) node, which is situated in the upper wall of the right atrium, and the atrioventricular (AV) node located in the lower wall of the right heart between the atrium and ventricle.

  7. Cardiac physiology - Wikipedia

    en.wikipedia.org/wiki/Cardiac_physiology

    Cardiac physiology or heart function is the study of healthy, unimpaired function of the heart: involving blood flow; myocardium structure; the electrical conduction system of the heart; the cardiac cycle and cardiac output and how these interact and depend on one another.

  8. Anatomy of the human heart - Wikipedia

    en.wikipedia.org/wiki/Anatomy_of_the_human_heart

    The heart is a muscular organ situated in the mediastinum.It consists of four chambers, four valves, two main arteries (the coronary arteries), and the conduction system. The left and right sides of the heart have different functions: the right side receives de-oxygenated blood through the superior and inferior venae cavae and pumps blood to the lungs through the pulmonary artery, and the left ...

  9. Cardiac pacemaker - Wikipedia

    en.wikipedia.org/wiki/Cardiac_pacemaker

    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.