Lecture XIX

• V: MECHANICAL EVENTS OF THE HEART. A: ATRIAL SYSTOLE

  • Step one
• V: MECHANICAL EVENTS OF THE HEART. A: ATRIAL SYSTOLE

  • finish filling heart (last 20-25%)
• V: MECHANICAL EVENTS OF THE HEART. B: VENTRICULAR SYSTOLE

  • Step two
• V: MECHANICAL EVENTS OF THE HEART. B: VENTRICULAR SYSTOLE

  • atrial diastole
• V: MECHANICAL EVENTS OF THE HEART. B: VENTRICULAR SYSTOLE

  • atrial diastole
  • pressure close atrioventricular valves: heart sound I (lub)
• V: MECHANICAL EVENTS OF THE HEART. B: VENTRICULAR SYSTOLE

  • atrial diastole
  • pressure close atrioventricular valves: heart sound I (lub)
  • heart contracts and builds pressure
• V: MECHANICAL EVENTS OF THE HEART. B: VENTRICULAR SYSTOLE

  • atrial diastole
  • pressure close atrioventricular valves: heart sound I (lub)
  • heart contracts and builds pressure
  • both sets of valves are closed
• V: MECHANICAL EVENTS OF THE HEART. B: VENTRICULAR SYSTOLE

  • atrial diastole
  • pressure close atrioventricular valves: heart sound I (lub)
  • heart contracts and builds pressure
  • both sets of valves are closed
  • no blood movement
• V: MECHANICAL EVENTS OF THE HEART. B: VENTRICULAR SYSTOLE

  • atrial diastole
  • pressure close atrioventricular valves: heart sound I (lub)
  • heart contracts and builds pressure
  • both sets of valves are closed
  • no blood movement
  • need to build pressure until ventricle > diastolic pressure
• V: MECHANICAL EVENTS OF THE HEART. C: VENTRICULAR SYSTOLE (EJECTION PHASE)

  • Step three
• V: MECHANICAL EVENTS OF THE HEART. C: VENTRICULAR SYSTOLE (EJECTION PHASE)

  • ventricle builds enough force to open semilunar valves
• V: MECHANICAL EVENTS OF THE HEART. C: VENTRICULAR SYSTOLE (EJECTION PHASE)

  • ventricle builds enough force to open semilunar valves
  • pressure continues to build until volume drops and ventricle is empty
• V: MECHANICAL EVENTS OF THE HEART. D: EARLY DIASTOLE (PHASE I)

  • Step four
• V: MECHANICAL EVENTS OF THE HEART. D: EARLY DIASTOLE (PHASE I)

  • semilunar valves close: heart sound II (dub)
• V: MECHANICAL EVENTS OF THE HEART. D: EARLY DIASTOLE (PHASE I)

  • semilunar valves close: heart sound II (dub)
  • ventricle pressure drops to low
• V: MECHANICAL EVENTS OF THE HEART. D: EARLY DIASTOLE (PHASE I)

  • semilunar valves close: heart sound II (dub)
  • ventricle pressure drops to low
  • some blood will back flow into ventricle
• V: MECHANICAL EVENTS OF THE HEART. D: EARLY DIASTOLE (PHASE I)

  • semilunar valves close: heart sound II (dub)
  • ventricle pressure drops to low
  • some blood will back flow into ventricle
  • all four valves closed
• V: MECHANICAL EVENTS OF THE HEART. E: LATE DIASTOLE (PHASE II)

  • Step five
• V: MECHANICAL EVENTS OF THE HEART. E: LATE DIASTOLE (PHASE II)

  • atrioventricular valves open because pressure is low
• V: MECHANICAL EVENTS OF THE HEART. E: LATE DIASTOLE (PHASE II)

  • atrioventricular valves open because pressure is low
  • ventricles start to fill
• V: MECHANICAL EVENTS OF THE HEART. E: LATE DIASTOLE (PHASE II)

  • atrioventricular valves open because pressure is low
  • ventricles start to fill
  • passive filling occurs
• Added Notes:

  • During exercise, skeletal muscle contraction pushes blood so more blood can be in ventricle for contraction
  • If someone was sitting during this, they would pass out because skeletal muscle is not pushing blood to heart
• Added Notes:

  • Sometimes the lub dub heart sound can be heard separately
• Added Notes:

  • Contraction is fast
  • Most time is for filling with blood
• I: VASCULATURE (BLOOD VESSELS)

  • arteries: blood goes away from heart
  • veins: return blood to heart
• I: VASCULATURE (BLOOD VESSELS). A: GENERAL OVERVIEW. 1: LAYERS OF BLOOD VESSELS. a: TUNICA EXTERNA / ADVENTITIA

  • made of dense irregular connective tissue
• I: VASCULATURE (BLOOD VESSELS). A: GENERAL OVERVIEW. 1: LAYERS OF BLOOD VESSELS. a: TUNICA EXTERNA / ADVENTITIA

  • made of dense irregular connective tissue
  • responsible for protecting and anchoring blood vessels
• Added Notes:

  • Tunica externa is the term that will be used
  • Tunica externa can vary due to genes
• I: VASCULATURE (BLOOD VESSELS). A: GENERAL OVERVIEW. 1: LAYERS OF BLOOD VESSELS. b: TUNICA MEDIA

  • made of smooth muscle: controlled by sympathetic division
• I: VASCULATURE (BLOOD VESSELS). A: GENERAL OVERVIEW. 1: LAYERS OF BLOOD VESSELS. b: TUNICA MEDIA

  • made of smooth muscle: controlled by sympathetic division
  • contract: vasoconstriction
  • dilation vasodilation
• I: VASCULATURE (BLOOD VESSELS). A: GENERAL OVERVIEW. 1: LAYERS OF BLOOD VESSELS. b: TUNICA MEDIA

  • made of smooth muscle: controlled by sympathetic division
  • contract: vasoconstriction
  • dilation vasodilation
  • relax smooth muscle
• I: VASCULATURE (BLOOD VESSELS). A: GENERAL OVERVIEW. 1: LAYERS OF BLOOD VESSELS. b: TUNICA MEDIA

  • made of smooth muscle: controlled by sympathetic division
  • contract: vasoconstriction
  • dilation vasodilation
  • relax smooth muscle
  • increases blood flow unless vasodilation is too widespread
• Added Notes:

  • Blood flow slows down because of vasoconstriction
  • Then pressure builds up before constricted point
• Added Notes:

  • Heat and alcohol increases dilation which is more dangerous
• I: VASCULATURE (BLOOD VESSELS). A: GENERAL OVERVIEW. 1: LAYERS OF BLOOD VESSELS. c: TUNICA INTERNA / INTIMA

  • made of areolar connective and simple squamous epithelium
• I: VASCULATURE (BLOOD VESSELS). A: GENERAL OVERVIEW. 2: TYPICAL VESSELS. a: ARTERIES AND SUBTYPES

  • high oxygen and high pressure
• I: VASCULATURE (BLOOD VESSELS). A: GENERAL OVERVIEW. 2: TYPICAL VESSELS. a: ARTERIES AND SUBTYPES

  • high oxygen and high pressure
  • decrease in diameter and wall thickness when farther away from the heart
• I: VASCULATURE (BLOOD VESSELS). A: GENERAL OVERVIEW. 2: TYPICAL VESSELS. a: ARTERIES AND SUBTYPES

  • high oxygen and high pressure
  • decrease in diameter and wall thickness when farther away from the heart
  • decrease in pressure the farther away from the heart
• I: VASCULATURE (BLOOD VESSELS). A: GENERAL OVERVIEW. 2: TYPICAL VESSELS. a: ARTERIES AND SUBTYPES. i: ELASTIC ARTERIES

  • resist high pressure and high volume
• I: VASCULATURE (BLOOD VESSELS). A: GENERAL OVERVIEW. 2: TYPICAL VESSELS. a: ARTERIES AND SUBTYPES. i: ELASTIC ARTERIES

  • resist high pressure and high volume
  • thick tunica externa
  • thick sorta tunica media