Heart

Cards (13)

  • The heart has 4 chambers: the left and right Atrium and Ventricles
  • Valves prevent backflow of blood into the atria when the ventricles contract.
  • The septum separates the two sides of the heart, preventing mixing of oxygenated and deoxygenated blood.
  • Heart problems:
    Tachycardia - when the heart beats too fast
    bradycardia - when the heart beats too slow
    Atrial fibrillation - rapid and irregular contraction of the atria
    ventricular fibrillation - rapid and irregular contraction of the ventricles
    ectopic heartbeat - irregular beating of the heart
  • Coronary artery disease is caused by fatty deposits on the walls of coronary arteries which can lead to blockages or ruptures causing myocardial infarction (heart attack)
  • graph of just a normal heart rate
    A) atria
    B) ventricles
    C) ventricles repolarise
  • Controlling heart rate:
    the heart initially is at diastole where it is at rest
    ->
    The SAN sends a nerve impulse which causes the atria to contract and push blood through the atrioventricular valves out into the relaxed ventricles
    ->
    the atrioventricular valves close (preventing backflow),the AVN delays the nerve impulse sent by the SAN then the ventricles recieve the impulse and constrict and force blood through the semilunar valves
  • The Sinoatrial node (SAN) is located at the right atrium of the heart and is the pacemaker responsible for regular rhythm of the heart beat
  • Valves in the heart?
    Atrioventricular valves, semilunar valves
  • What is the name of the structure responsible for conducting electrical stimulation around the walls of the ventricle?
    The bundle of his
  • What is the name of the fibres contained in the bundle of His?
    Purkinje fibers
  • What is meant by the term atrial fibrillation?
    An abnormal heartbeat where rapid electrical impulses lead to rapid and incomplete contractions of the atria.
  • What is meant by the term ectopic heartbeat?
    extra or skipped heart beats that are not apart of the normal rhythm