Normal and Abnormal Cardiac Rhythm Tutorial

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1. What controls the normal rhythm of the heart?
2. How do autonomic nerves, circulating catecholamines, extracellular potassium concentrations, thyroid hormone, and hypoxia alter pacemaker activity?
3. How do autonomic nerves, circulating catecholamines, cellular hypoxia, and drugs blocking sodium channels  alter conduction velocity within the heart?
4. What are arrhythmias?
5. Define each of the following types of arrhythmias:
   
   1. sinus rhythm
   2. sinus bradycardia
   3. sinus tachycardia
   4. sick sinus syndrome
   5. atrial tachycardia
   6. atrial flutter
   7. atrial fibrillation
   8. junctional escape rhythm
   9. AV nodal blocks - first, second and third degree
   10. supraventricular tachycardia
   11. ventricular premature beat
   12. ventricular tachycardia
   13. ventricular flutter
   14. ventricular fibrillation
6. How can altered automaticity and conduction cause arrhythmias?
7. What are early- and delayed-afterdepolarizations and what can cause them?
8. What are ectopic foci?
9. Under what conditions and by what mechanisms can a non-pacemaker cell become a pacemaker cell?
10. What are reentry currents, how can they lead to tachyarrhythmias, and how can changes in conduction velocity and the relative refractory period either precipitate or abolish reentry currents?
11. What are the hemodynamic consequences of arrhythmias?

Revised 11/03/06