HEART ACTION

1
HEART ACTION
PHUNEE RATANASAENG
2
???????????????????????????

• ??????
• atrium
• atrium --gtventricle (????, ???)
• ventricle
• ventricle --gtpulmonary a. (???)
• ventricle --gt aorta (????)

3
???????????????????????????

• ???????
• atrium (diastole)
• vena cava --gtatrium (???)
• pulmonary vein --gt atria (????)
• ventricle
• atrium --gtventricle (????, ???)

4
??????????????? (cardiac tissue)

• 3 ????
• 1. ????????????????????????? (cardiac muscle
  fibers)
• 2. ??????????????? ???????????????????????????
  ????????? (nodal cells)
• 3. ?????????????????????????????????????????
  (conducting cells)

5
????????????????????????? (cardiac muscle fibers)

• ??????? atria ventricle
• ????? all-or-none ( ??? threshold )
• ??????????????????????????????? ???????????
• ??????????????????????????????? syncytium

6
??????????????? ?????????????????????????????????
??? (nodal cells)

• ???????? 2 ?????
• ?. sino atrial node (S-A node)
• atrium ???
• ??? 25-30 ??. ??? 2-5 ??.
• vagus ??? sympathetic nerve
• ?????????????????????????????????????????
  ????????????????

7
??????????????? ?????????????????????????????????
??? (nodal cells)

• ?. atrio-ventricular node (A-V node)
• ?????????????? atrium ???????, ???????????????????
  ??? atrium ??? ventricle
• ???????? S-A node ??????????????????????
• ??? 5 ??. , ??? 2-6 ??.
• vagus ??? sym. Nerve.
• ???????????????????????????????? ventricle

8
?????????????????????????????????????????
(conducting cells)

• ??????
• bundle of His ???????? ???
• Purkinje system
• ????????????????? ???????????????????????? ???
  ventricle ???? 2

9
???????????????????????????????????

• Resting
• Resting potentials ??????????????????? 80 ???
  100 mV
• action potentials

10
????????????????????????

• ????????
• ???? depolarization
• ???? repolarization
• ??????? (resting)

11
Depolarization

• ???? depolarization ??? - 50 mV (Ca2
  ????????? ????????
• phase 0 depolarization ??????? overshoot
  (?????????????????????????? 0 mV)

12
Repolarization

• ???? repolarization ????????
• phase 1 ??????? repolarization
  ????????????????????????????????????????????????
• phase 2 ?????????????????? (plateau)
• ???? 0.1-0.2 ??????
• phase 3 ???????? repolarization
  ??????????????????????????????????????????????????

13
Resting

• ??????? (resting)
• phase 4 ?????????????????????????????????????
  ??????????? ?????? (diastole)
• ??????????????cell ???????????????? cell ??????
• phase 0 ??????????? ??????????????? ???
  repolarization ?????????????????
• action potential ?? plateau

14
????????????????????

• depolarization 2 ???????????
• replarizatin gt 200 ???????????
• ????? repolarization ?????????????????????????????
  ?????????????????????
• ??????????????????????? tetanus
  ?????????????????

15
??????? plateau

• ?????????????????????? 0 ????????????? 0 mV
• ????????
• 1. ????? cell ?? Pk ??? PNa ??????? (ER
  ??????? K gradient)
• 2. Ca2 ???????????????? ????? Ca2 ????
  phase 2 ???????

16
Absolute refractory period ?????????? phase 0
--gt 3 (-60 mV) Relative refractory period
??????????? ???????????????????????????
phase 3 --gt???????
refractory period
17
??????????????????????????

• action potential ???????? ????????????
  (ca2)?????
• ????? ??????? 1 ½ ?????????????????? action
  potential
• ??? syncytium
• ??? all or none

• ??????? ????????????????????????????????
• ?? contractile proteins ?????????????????????????
• T
• pH
• ion ?????????? cell
• ??????? fiber ?????????

18
?????????????????????????

• Cardiac output (C.O.) ??????? ????????????????????
  ????????? 1 ???? ??????????? L/min
• ??????? 1. ????????????????? (heart rate, HR)
• 2.??????????????????????????
  ventricle??????????????????????????????? (Stroke
  volume, SV)

19
C.O. (L/min.) HR. x S.V. ?????/????
???????????????????????? ????????????? 5-6
????/???? ???? 90 ?????????/????/?????????????
? 1 kg. ???????????????? 20 ????/????
??????????????? 40 ????/????
Cardiac output
20
Stroke Volume (S.V.)

• ??????? ?????????????????????????? ventricle
  ???????????????????????????????
  ??????????????????????????????????? (ventricle)
  ??????????
• ?????????? (end diastolic volume, EDV)
• ?????????????? (end systolic volume, ESV)
• SV EDV ESV
• SV ???????????????? 70-80 ?????????/?????

21
????????????????? (Heart Rate, HR)

• ?????? 70-75 ?????/????
• ??????? 135 ?????/????
• ??????? 50 ?????/????
• R-R interval HR
• ??????????????????

22
?????????????????? (Electrocardiogram, ECG)

• ??????? ??????????????????????????????????????????
  ?????????????????? action potential ???????
• ECG ???????????? impulse ??????? ??????? cell
  ????????

23
??????????????????

• S-A node impulse ?????????
• Depolarizaln ????????
• Dipole ??????????????????????? 2 ????
• ??????????????????????????????????
  ????????????????
• ???????????????????????????????????????????????
  ????????????????????????????????

24
????????? ECG

• ??????? ??????, ???????????, ???????????????????
  ?????????
• ?????????????????????????????????????????????
• Extracellular recording ???????
  ?????????????????????????????????? 2 ??? ???? ECG
• Intracellular recording ???????
  ??????????????????????????????????????????? ????
  action potential

25
????????? ECG

• ????????
• ???????? ???????????????????????? (rate rhytun)
• ???????????? ??????????? (hypertrophy),
  ?????????????????????????????? (ischemia ????
  infraction)
• ??????????????????????
• ???????????????????????????????? arrhythmia
  ?????????

26
1 ??????????????????????????????? 3 ?????
27

• ECG ?????????????????????????????
• P wave ???????? atrial contraction
• QRS complex ???????? ventricular systole
• T wave ???????? ventricular relaxation

28
??????????????????????? action potential
??????????? ECG

• P wave ?????? atrial depolarization
• PR segment ?????? delay ??? AV node
  ????????
• QRS complex ?????? ventricular depolarization
• (???????????? QRS complex ?????????????????
  depolarization ventricle ???????
• ST segment ?????? ???? plateau
• T wave ?????? ventricular repolarization