Emergency cardioversion and defibrillation are life-saving procedures that
exert direct electric current to the heart through the chest wall in order to terminate
lethal tachyarrhythmias. Early defibrillation is life-saving in the survival of adult
patients who develop sudden cardiac arrest. In the defibrillation process, myocardial
cells are depolarized, and VF is terminated by delivering a certain amount of direct
current to the heart, passing through the chest wall. Proper timing and accurate
performance of these procedures have a vital role in both survival and recovery postresuscitation
neurological functions without sequelae. Return of spontaneous
circulation (ROSC) rates in defibrillation performed without losing time (within 20-30
seconds) can be up to 100% following the occurrence of these lethal rhythms. While
cardioversion is performed in pulsating contraction rhythms, defibrillation is an
electrical stimulation procedure applied in rhythms that do not generate pulses. In the
cardioversion, synchronous energy is exerted onto the QRS complex to convert the
rhythm into a sinus rhythm.
When there are signs of instability in rhythms with a pulse, emergency cardioversion
(ECV) can be preferred over all other treatments if it is known to have acute onset (less
than 48 hours) in atrial rhythm disorders, Transcutaneous pacing (TCP) is a
recommended practice for temporary stabilization and invasive techniques such as
transvenous pacing (TVP) should be attempted for longer pacing requirements. This
chapter gives a brief outline on the outstanding features of electrotherapies (i.e., ECV;
defibrillation; TCP, TVP) both in case of life-threatening dysrhythmias and also in
urgent non-lethal situations.
Keywords: Cardioversion, Defibrillation, Electrotherapies, Transcutaneous
pacing, Transvenous pacing.
