Cardioversion and defibrillation both use electrical shocks to treat abnormal heart rhythms, but they differ in their timing, energy level, and use. Cardioversion delivers a lower energy shock synchronized to a specific part of the heartbeat to convert rhythms like atrial fibrillation. Defibrillation provides an unsynchronized higher energy shock to non-organized rhythms like ventricular fibrillation during cardiac arrest. Biphasic shocks are now preferred over monophasic shocks for greater success and safety. Different types of defibrillators include AEDs, professional devices, and implanted defibrillators.

1. Cardioversion Vs. Defibrillation

2. • The goal of both defibrillation and
cardioversion is to transfer electrical energy to
the heart.
• While both use the same general action and
can use the same equipment, the method is
different, as well as when you use them, how
you use them, and why you’re shocking the
heart.

3. • doctors use cardioversion to convert heart
rhythm when a patient has an unstable heart
but is not immediately in danger of dying
Cardioversion stabilizes the heart rhythm.
• Second, doctors synchronize cardioversion to
achieve a specific rhythm outcome. You don’t
time defibrillation. You just need a shockable
rhythm.

4. • Third, a defibrillator delivers a higher energy
dose vs. cardioversion.
• cardioversion performed when needed could
prevent a subsequent cardiac arrest
• But once a cardiac arrest occurs, defibrillation
is your only option–that is, if you have a
shockable rhythm
• electrical shocks cannot restart a heart that
has no electrical activity at all (asystole).

5. • Giving the heart such an electrical shock is
called cardioversion, or defibrillation,
depending on the type of abnormal rhythm
for which it is used.

6. Cardioversion
• Cardioversion is giving an electrical shock
timed (synchronized) to a specific part of the
heart beat. It may be used for arrhythmias
starting in the atria (such as atrial fibrillation)
or the ventricles (such as ventricular
tachycardia) as long as there is some type of
organized electrical activity in the heart.

7. • Doctors achieve this timing by viewing a defibrillator
monitor or using a machine that syncs to the rhythm
automatically.
• They sync the shock to a specific point in the QRS
complex
• Through this method, atrial fibrillation can be
converted to a normal sinus rhythm while preventing
the prompting of ventricular fibrillation (VF). This
happens because you’ve synchronized the electrical
shock to the R wave. At the same time, you avoided
that susceptible T-wave and averted ventricular
fibrillation.

8. Defibrillation
• Defibrillation is giving an electrical shock
during ventricular fibrillation. During
ventricular fibrillation, there is no organized
electrical activity in the heart to which the
shock can be timed

9. Monophasic Vs. Biphasic Shock
• A monophasic shock only travels in one direction
from one paddle to another can give 360 Joules
(J).
• while a biphasic shock travels from one paddle to
the other and then back several times. Biphasic
shock results in fewer burns and has a higher first
shock success rate (90% to 60%). initially of 150-
200 J. Then use subsequent shocks incrementally
150, 200, 300, 360 J.

10. Types of Defibrillators
• Automated External Defibrillators (AEDs) are often
found in CPR kits for the average person with CPR
training.
• Semi-automated AEDs can be overridden and are
therefore only used by a trained professional like a
paramedic.
• Standard defibrillators with monitors require
professional skills to operate. You’ll find them in
hospitals mostly.
• Implanted defibrillators can shock the heart back into a
rhythm during a cardiac arrest without assistance from
a bystander.