Reference no: EM133848517

Question 

Normal Function of the Cardiovascular System

1. Describe in detail (including valves) the path that blood takes as it enters the heart from the Vena cava until its final entrance into the Aorta.

2. Review the structure of the heart valves. Between which two structures do we find valves? Between which two structures in the heart do we NOT find valves?

3. Describe the structure and function of the pericardial sac?

4. What are the unique structural features of cardiac muscle?

5. Consider the gap junctions located in the intercalated disks of cardiac muscle. Think about some consequences of selective blockade of those junctions.

6. Describe and explain the ionic basis of the action potential in the autorhythmic cells in the heart.

7. Describe and explain the ionic basis of the action potential in the cardiac muscle cells?

8. Where are the autorhythmic cells located in the heart? What is the direction of flow of the action potential?

9. Why is the Sinoatrial node considered the pacemaker of the heart? What area of the heart would become the pacemaker if the SA node stopped functioning?

10. What is the purpose of the AV nodal delay?

11. If you were to cut off all parasympathetic and sympathetic innervation to the heart, what would heart rate be? Explain why?

12. Explain what electrical events happening in the heart generate the waveforms seen in a 12 lead EKG.

13. If you were to look at a series heart cycles on an EKG, the distance between which two waveforms would decrease if heart rate increased?

14. Review all the electrical and mechanical events of the cardia cycle.

15. What are the only times during the cardiac cycle that ventricular volume is not changing?

16. Describe all the electrical and mechanical events of the cardiac cycle that correspond in time with the QRS complex (and just after, 30-40 msec, the QRS complex) on the EKG?

17. Describe the pressure differences during Isovolumetric contraction between:

(a) The ventricles and the atria

(b) The ventricles and the arteries

18. What is the required change that allows the ventricles to move from Isovolumetric contraction to the ejection phase?

19. Think of the mechanical events that take place during the second heart sound and answer the following.

What is happening in terms of aortic vs. ventricular pressure?

What is happening electrically in terms of the EKG?

What is happening in terms of the heart valves?

20. If a patient had an alteration in his second heart sound (ex. the sound was muffled or involved an abnormal whistle), this would most likely indicate a problem with what structure in the heart?

21. A patient with hypertension has a systolic blood pressure of 140mmHg and a diastolic blood pressure of 95mmHg. How high must left ventricular pressure reach in order to end isovolumetric contraction in this patient (give a number value)?