What electrical event occurs in the myocardium that generates the portion of the ECG marked P 43. What do the atria do in response to this event?

t for chest pain that is ore s also NIT EIGHT monary Examine the electrocandiogram (ECG) and annwer the queations about it 42. What electrical event occurs in the myocardium that generates the portion of the ECG marked P 43. What do the atria do in response to this event? 44. Electrical signals are conducted through what parts of the heart during the PR interval? 45. What are the ventricles doing during the portion of the ECG that is shaded in the diagram (R through end of ‘T wave)? 46. The mitral valve closes at approximately what location on the ECG? 47. Why is it important for the mitral and tricuspid valves to close at that time?