A70-year-old woman with ongoing severe atrial fibrillation is scheduled for defibrillation. what is an aspect of the rationale and physiology of defibrillation treatment? a. interruption of disorganized impulses by the current allows the av node to readopt its normal pacemaker role. b. the goal is to depolarize the entire heart during the passage of current. c. defibrillation can be achieved using either a transcutaneous or transvenous pacemaker. d. defibrillation must be coincided with the r wave of the ecg in order to be successful.

Defibrillation is a method of emergency medicine that can stop ventricular fibrillation or pulseless ventricular tachycardia. An electricity is used to reset the electrical state of the heart so that heart beat will have rhythm controlled by its pacemaker. This is not used in asystole and pulseless electrical activity. Defibrillator is used to give an electric shock to the heart. This depolarizes the muscles in the heart which stops the dysrhythmia, the SA node can eventually produce its own electrical impulse which establish the normal sinus rhythm of the heart. Cardioversion can also be done to provide normal rhythm in poorly perfusing cardiac dysrthymias. 

Defibrillators can be implanted, external, transvenous depending on the type of devide used or needed in the current situation.