Cardiovascular Physiology Concepts
                                    Richard E. Klabunde, Ph.D.

Cardiac Electrophysiology Tutorial

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1. What are the normal concentrations of sodium, potassium, and calcium ions inside and outside of a cardiac myocyte?  click here

2. What is the Nernst potential?  What is an equilibrium potential?  click here

3. How does changing the concentrations of sodium, potassium, and calcium ions inside and outside the cell affect the resting membrane potential in cardiac cells?  click here

4. What is the role of the sarcolemmal Na⁺/K⁺-ATPase in the generation and maintenance of cardiac membrane potentials?  click here  

5. How are calcium gradients maintained across the cardiac cell membrane?  click here  

6. How do changes in the relative ionic conductances of sodium, potassium, and calcium ions affect the membrane potential?  click here

7. How are cardiac action potentials different from those found in nerve cells?  click here

8. What ionic currents are responsible for pacemaker action potentials?  click here

9. How do autonomic nerves, circulating catecholamines, extracellular potassium concentrations, thyroid hormone, and hypoxia alter pacemaker activity?  click here

10. What ionic currents are responsible for non-pacemaker action potentials?  click here

11. What is the effective refractory period (ERP) for an action potential and what can cause it to lengthen or shorten?  click here  

12. What is the normal sequence and pathways for depolarization within the heart?  click here 

13. How do autonomic nerves, circulating catecholamines, cellular hypoxia, and drugs blocking sodium channels  alter conduction velocity within the heart?  click here

DISCLAIMER: These materials are for educational purposes only, and are not a source of medical decision-making advice.

© 1999-2008 Richard E. Klabunde, all rights reserved.