A nurse assesses the heart after acetylcholine because the effect ...

[PhilipSeeMore]

A nurse assesses the heart after acetylcholine because the effect of acetylcholine on the heart is to:
 
  a. decrease the refractory period.
  b. increase calcium influx.
  c. increase the strength of myocardial con-traction.
  d. decrease the heart rate.

Question 2

What represents the sum of all ventricular muscle cell depolarization?
 
  a. PR interval
  b. QRS complex
  c. QT interval
  d. P wave

[Briannahope]

Answer to Question 1

ANS: D
Acetylcholine causes decreased heart rate and slows conduction through the AV node; it does not decrease the refractory period nor does it increase calcium influx. It does not increase the strength of myocardial contraction.

Answer to Question 2

ANS: B
The QRS complex represents the sum of all ventricular muscle cell depolarizations. The PR inter-val represents the onset of atrial activation to the onset of ventricular activity. The QT interval represents electrical systole of the ventricles. The P wave represents atrial depolarization.