Physiology II - seminar

Seminar IV: Heart as a Muscle

Preparation (self-studying – study following topics prior to the ROPOT)

Action potential of the ventricular myocardium. Relationship between action potential and contraction of the ventricular myocardium. Anatomy of coronary vessels – coronary arteries, cardiac veins. Cardiac contractility – definition. Preload, afterload – definitions. Heterometric and homeometric autoregulation of the contraction force. Overview of the cardiac cycle – phases. PV diagram of the left ventricle – shape, description. Basic shape of ECG curve. Heart sounds, phonocardiography.

 

Content

1.   The heart as a muscle

Electric and mechanic properties of cardiac muscle. Relationship length-tension. Cardiac output. Cardiac reserve. Energetic metabolism of the heart. Coronary circulation – function, regulation. Coronary reserve.

 

2.   Cardiac contractility. Regulation and autoregulation of myocardium contraction force

Cardiac contractility and factors, which affect it (temperature, ATP, Ca2+, heart rate). Assessment of cardiac contractility, clinically relevant indexes of contractility (dP/dt, LVEF).

Determinants of cardiac output – preload, afterload. Effect of autonomic nervous system on myocardium contraction force. Heterometric and homeometric autoregulation of myocardium contraction force – physiological impact.

 

3.   Cardiac cycle

Cardiac cycle – overview of phases, endsystolic and enddiastolic volume of the ventricles. PV diagram, work of the left ventricle. Changes of cardiac work (PV diagram) in case of increased preload and increased afterload.

 

4.   Polygraph

Time-relationship between the ECG, the phonocardiogram, the pressure curve in the left ventricle and the pressure curve in the aorta.

 

Schedule

date

time

group

26. 4. 2021

16:00 – 17:50

30

 

16:00 – 17:50

31

27. 4. 2021

17:00 – 18:50

36

28. 4. 2021

14:30 – 16:20

34

 

14:30 – 16:20

35

3. 5. 2021

16:00 – 17:50

38

 

16:00 – 17:50

39

4. 5. 2021

17:00 – 18:50

33

5. 5. 2021

14:30 – 16:20

32

 

14:30 – 16:20

37