What does ST depression often indicate

7. What does ST depression often indicate? Why? 8. What is Myocardial Infarction? 9. What is the approximate amount of time from the end of atrial depolarization to beginning of ventricular depolarization? Why is this necessary? 10. Determine heart rate of the subject using the ECG printout for 3 occasions. Report results. 11. During what phase of the ECG does Diastolic filling occur? When would pre-load peak? 12. Considering their extremely small size, how can the atria "fill" the ventricles 2004 NorthPoint Domain prior to their contraction? 13. Assume the p wave is entirely absent – what does this mean? If the p wave is Questions and Discussion consistently absent, how might this affect cardiac function? 1. What part of the ECG tracing represents depolarization of the ventricles? 2. What part of the ECG tracing represents repolarization of the ventricles? 14. Why would an electrical shock potentially "revive" a non-beating heart? 3. What part of the ECG tracing represents depolarization of the atrium? 4. What parts of the trace coincide with myocardial contraction, and therefore forward movement of the blood? 5. Where does a usual, customary heartbeat originate? 6. Where do premature ventricular contractions (PVC) originate?