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  2. Cardiac excitation-contraction coupling - Wikipedia

    en.wikipedia.org/wiki/Cardiac_excitation...

    EC coupling results in the sequential contraction of the heart muscles that allows blood to be pumped, first to the lungs (pulmonary circulation) and then around the rest of the body (systemic circulation) at a rate between 60 and 100 beats every minute, when the body is at rest. [2]

  3. 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 ...

  4. Cardiac physiology - Wikipedia

    en.wikipedia.org/wiki/Cardiac_physiology

    The cardiomyocytes make up the bulk (99%) of cells in the atria and ventricles. These contractile cells respond to impulses of action potential from the pacemaker cells and are responsible for the contractions that pump blood through the body. The pacemaker cells make up just (1% of cells) and form the conduction system of the heart.

  5. Cardiac pacemaker - Wikipedia

    en.wikipedia.org/wiki/Cardiac_pacemaker

    It employs pacemaker cells that produce electrical impulses, known as cardiac action potentials, which control the rate of contraction of the cardiac muscle, that is, the heart rate. In most humans, these cells are concentrated in the sinoatrial (SA) node, the primary pacemaker, which regulates the heart’s sinus rhythm.

  6. Sinoatrial node - Wikipedia

    en.wikipedia.org/wiki/Sinoatrial_node

    These cells produce an electrical impulse known as a cardiac action potential that travels through the electrical conduction system of the heart, causing it to contract. In a healthy heart, the SA node continuously produces action potentials, setting the rhythm of the heart ( sinus rhythm ), and so is known as the heart's natural pacemaker .

  7. Cardiac cycle - Wikipedia

    en.wikipedia.org/wiki/Cardiac_cycle

    The movements of cardiac muscle are coordinated by a series of electrical impulses produced by specialized pacemaker cells found within the sinoatrial node and the atrioventricular node. Cardiac muscle is composed of myocytes which initiate their internal contractions without receiving signals from external nerves—with the exception of ...

  8. Pacemaker potential - Wikipedia

    en.wikipedia.org/wiki/Pacemaker_potential

    It employs pacemaker cells that generate electrical impulses, known as cardiac action potentials. These potentials cause the cardiac muscle to contract, and the rate of which these muscles contract determines the heart rate. As with any other cells, pacemaker cells have an electrical charge on their membranes.

  9. Electrophysiology - Wikipedia

    en.wikipedia.org/wiki/Electrophysiology

    dissociated cells from excised tissue (acute or cultured), artificially grown cells or tissues, or; hybrids of the above. Neuronal electrophysiology is the study of electrical properties of biological cells and tissues within the nervous system.