What is synchronized cardioversion and when is it used

Synchronized cardioversion is used to treat other arrhythmias, including atrial fibrillation (AF), atrial flutter and stable ventricular tachycardia when medications have failed to convert the rhythm, or when the patient is becoming unstable and the rhythm must be immediately terminated.

What is synchronized electrical cardioversion?

Synchronized cardioversion is a procedure similar to electrical defibrillation in that a transthoracic electrical current is applied to the anterior chest to terminate a life-threatening or unstable tachycardic arrhythmia.

What are the indications for cardioversion?

• Supraventricular tachycardia (atrioventricular nodal reentrant tachycardia [AVNRT] and atrioventricular reentrant tachycardia [AVRT])
• Atrial fibrillation.
• Atrial flutter (types I and II)
• Ventricular tachycardia with pulse.

Who requires immediate cardioversion?

Three types of cardioversion can be used to attempt to change the rhythm of the heart. The initial evaluation for which type to use is the patient’s hemodynamic status. If the patient is hypotensive, has chest pain, altered mental status, or heart failure, immediate electrical cardioversion should be considered.

What rhythms require synchronized cardioversion?

The most common indications for synchronized cardioversion are unstable atrial fibrillation, atrial flutter, atrial tachycardia, and supraventricular tachycardias. If medications fail in the stable patient with the before mentioned arrhythmias, synchronized cardioversion will most likely be indicated.

When do you use synchronized vs unsynchronized cardioversion?

Defibrillation or unsynchronized cardioversion is indicated in any patient with pulseless VT/VF or unstable polymorphic VT, where synchronized cardioversion is not possible. Synchronized cardioversion is utilized for the treatment of persistent unstable tachyarrhythmia in patients without loss of pulse.

Why does cardioversion need to be synchronized?

The reason a shock must be synchronized is that the cardiac cycle has both a vulnerable and a refractory period. The refractory period occurs during the QRS complex (see the image below).

Has anyone ever died during cardioversion?

With serial cardioversion 90% of the patients were kept in sinus rhythm for 5 years. Univariate analysis showed that a long duration of arrhythmia and impaired cardiac function were both related to poor outcome. During follow up 3 patients died of progression of heart failure and another 5 died suddenly.

Which is better cardioversion or ablation?

Conclusion: In patients with AF, there is a small periprocedural stroke risk with ablation in comparison to cardioversion. However, over longer-term follow-up, ablation is associated with a slightly lower rate of stroke.

Is defibrillation synchronized?

Defibrillation involves the delivery of a high-energy shock without the need to time the shock to the unstable rhythm (see the image below). In this example, the delivered shock is not synchronized with the ECG because the rhythm is unstable and there is no apparent QRS complex or T wave to avoid.

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What is the difference between defibrillator and cardioversion?

There is an important distinction between defibrillation and cardioversion: Defibrillation — Defibrillation is the asynchronous delivery of energy, such as the shock is delivered randomly during the cardiac cycle. Cardioversion — Cardioversion is the delivery of energy that is synchronized to the QRS complex.

For which patient should synchronized cardioversion be considered to terminate ventricular tachyarrhythmias?

Based on advanced cardiac life support (ACLS) guidelines, any patient with a narrow or wide QRS complex tachycardia (ventricular rate >150 beats per minute [bpm]) who is unstable (eg, chest pain, pulmonary edema, lightheadedness, hypotension) should be immediately treated with synchronized electrical cardioversion.

What is unstable tachycardia?

An unstable tachycardia exists when cardiac output is reduced to the point of causing serious signs and symptoms. Serious signs and symptoms commonly seen with unstable tachycardia are: chest pain, signs of shock, SOA (short of air), altered mental status, weakness, fatigue, and syncope.

Is synchronized cardioversion appropriate for treating an unknown wide complex tachycardia?

Synchronized cardioversion is appropriate for treating wide complex tachycardia of unknown type. Prepare for synchronized cardioversion as soon as a wide complex tachycardia is detected.

Do you shock V tach with a pulse?

Under current resuscitation guidelines symptomatic ventricular tachycardia (VT) with a palpable pulse is treated with synchronised cardioversion to avoid inducing ventricular fibrillation (VF), whilst pulseless VT is treated as VF with rapid administration of full defibrillation energy unsynchronised shocks.

Do you shock VT with a pulse?

Ventricular tachycardia is a poorly perfusing rhythm; patients may present with or without a pulse. Most patients with this rhythm are unconscious and pulseless and defibrillation is needed to “reset” the heart so that the primary pacemaker (usually the Sinoatrial Node) can take over.

Does your heart stop during electrical cardioversion?

If your doctor recommends cardioversion with medications to restore your heart’s rhythm, you won’t receive electric shocks to your heart. Cardioversion is different from defibrillation, an emergency procedure that’s performed when your heart stops or quivers uselessly.

What is life expectancy after an ablation?

After a single ablation procedure, arrhythmia-free survival rates were 40%, 37%, and 29% at one, two, and five years. Most recurrences occurred within the first six months, while arrhythmias recurred in 10 of 36 patients who maintained sinus rhythm for at least one year.

What percentage of Cardioversions are successful?

The success rate of cardioversion with atrial fibrillation is generally better than 90 percent. Chances of success are lower when the atrial fibrillation has been present for more than several months or when the left atrium is very enlarged. In general, there are two ways that a cardioversion procedure for AF can fail.

Do they put you to sleep for cardioversion?

Cardioversion is usually a scheduled procedure. But sometimes healthcare providers need to do it as an emergency . This is done if symptoms are severe. You will be given medicine to put you to sleep before delivering the shocks.

What are the chances of dying from cardioversion?

Results. Electrical cardioversion success rate was 90.4%. Within a year after cardioversion one patient (0.6%) suffered myocardial infarction, three patients (1.9%) had a stroke/transitory ischemic attack (TIA), three patients (1.6%) died and three patients (1.9%) had a bleeding event that required hospitalization.

Does cardioversion weaken the heart?

It might not work: Cardioversion doesn’t always fix a fast or irregular heartbeat. You may need medicine or a pacemaker to control things. It might make things worse: It’s unlikely, but there’s a small chance that cardioversion could damage your heart or lead to more arrhythmias.

What rhythms do you defibrillate?

Defibrillation – is the treatment for immediately life-threatening arrhythmias with which the patient does not have a pulse, ie ventricular fibrillation (VF) or pulseless ventricular tachycardia (VT).

How many types of cardioversion are there?

There are two types of cardioversion. Chemical cardioversion uses medications that can relax an overactive heart. Electrical cardioversion uses one or more quick electric shocks to the heart. The shock is delivered through electrodes attached to the chest.

What is another name for cardioversion?

CardioversionMeSHD004554

What voltage is used for cardioversion?

The current external electrical cardioversion technique relies on the application of a selected amount of energy, which is generally between 50-360 J, via two electrodes (paddles).

For which patient should the risk for complications of synchronized cardioversion be seriously considered?

Patients with pre-existing cardiovascular disease, particularly structural heart disease and older patients (defined as age 65 and older, to error on the side of inclusion) are at risk for life-threatening complications following cardioversion.

Where does sinus tachycardia originate?

People develop sinus tachycardia when the sinus node in the heart sends electrical impulses more quickly than normal. It can occur as a result of a particular trigger, such as exercise, caffeine, or stress.

What is symptomatic tachycardia?

Tachycardia heartbeat In tachycardia, an abnormal electrical impulse starting in the upper or lower chambers of the heart causes the heart to beat faster. Tachycardia is the medical term for a heart rate over 100 beats per minute.

When should cardioversion not be delayed?

Ventricular rates often exceed 150 beats per minute. Patients frequently demonstrate signs of poor perfusion including hypotension, angina, altered mental status, or heart failure. Sedation prior to cardioversion is desirable, although cardioversion should not be delayed if sedatives are not immediately available.

How do you stop tachycardia in episode?

You may be able to stop an episode of SVT by using particular movements such as holding your breath and straining as you would during a bowel movement, dunking your face in ice water, or coughing.