Reference no: EM13673956
1. What major movements of ions account for each phase of the action potential of a typical myocardial cell?
2. Why is the cardiac action potential propagated more slowly in an AV node cell then in an atrial or ventricular myocyte?
3. By what pathway does a cardiac impulse that originates in the SA node arrive in the ventricular myocardium?
4. How do electrical signals move from cell to cell in the myocardium?
5. What electrophysiological conditions lead to reentry?
6. What electrocardiographic changes occur in first, second and third degree AV block?
7. What happens to contraction in a contractile cell if a wave of depolarization passing through the heart bypasses it?
8. A beta-blocker is an antagonist to beta one adrenergic receptors. What will this drug do to someone's heart rate?
Why is that response helpful following a heart attack?
9. Occasionally an ectopic pacemaker will develop in part of the conducting system of the heart. What happens to heart rate if an ectopic pacemaker depolarizes at a rate of 120 times per minute?
10. What are cardiac preload and afterload, and how do they affect developed pressure and velocity of contraction?
11. What changes would take place in the stroke volumes of right and left ventricles if a substantial opening was made in the interatrial septum in the course of a cardiac catheterization?
12. If a person suffers from a myocardial infarction, in which wave or waves of the electrocardiogram would you expect to see abnormal changes?
13. Is pressure in the atrium higher or lower than pressure in the venae cavae during atrial filling?
14. Which chamber has higher pressure during the following phases of the cardiac cycle? A) ventricular ejection, b) isovolumic ventricular relaxation, c) atrial and ventricular diastole, d) isovolumic ventricular contraction.