ECG lab

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ECG lab
2014-11-03 03:15:45
ECG lab Heart blood pressure

ECG lab study questions
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  1. Explain the changes in heart rate between the supine and seated position.Difference between supine and "after exercise conditions" Describe the physiological mechanisms causing these changes
  2. Are there differences in the cardiac cycle with the respieratory cycle.
  3. WHat changes occurred in the duration of systole and diastole between resting and post exercise?
  4. COmpared to the resting state, do the durations of the ECG intervals and segments decrease during exercise? explain
  5. In order to beat, the heart needs three types of cells. Describe the cells and their function.
    • Rhythmic generators: produce electrical signal (SA node/ pacemaker)
    • Conductors: to spread pacemaker signal
    • COntractile cells: myocardium to mechanically pump blood.
  6. List in proper sequence, starting witht he normal pacemaker, elements of the cardiac conduction system.
  7. Describe three cardiac effects of increased sympathetic activit, and of increased parasympathetic activity.
    • sympathetic: an increase in heart rate
    • enhancement of the contractile force of heart muscles
    • acceleration of atrioventricular conduction.

    • Parasympathetic: digestion
    • fuel storage
    • endorphins
  8. In the normal cardiac cycle, the atria contracts before the ventricles. where is this fact represented in the ECG?
  9. what is meant by AV delay and what purpose does the delay serve?
  10. What is the isoelectric line of the ECG?
  11. WHat is the difference between and interval and a segment.
  12. what are the three components of a "lead" adn describe their arrangement for lead II
  13. what does each of the following represent?
    • P wave: Depolarization of the right and left atria
    • P-R interval: Time from the onset of atrial depolarization to the onset of ventrical depolorization.
    • P-R segment: time of impulse conduction from the av node to the ventricular myodardium. 
    • QRS wave: depolorization of the right and left ventricles. 
    • S-t segment: period of time representing the early part of ventricular repolorization during which ventricles are made or less uniformely excited. 
    • T-wave: repolarization of the right and left ventricles
    • Q-T interval: time from onset of ventricular depolarization to end of ventricular repolarization. 
    • R-R interval: time between two successive ventricular depolarization. 
    • T-p segment: time from the end of ventricular repolarization to the onset of atrial depolarization. 
    • Ventricular systole: when the electrical signal of a depolarization reaches the contractile cells. 
    • Ventricular diastole: repolorization singnal reaches the myocardial cells, they relax.