Cardioversion

 DC cardioversion (Direct Current cardioversion) is a procedure used to restore a normal heart rhythm by delivering a controlled electrical shock to the heart. 

How does it work?
Adhesive pads (or paddles) are placed on the chest. The electrical shock is carefully synchronised with the heartbeat. This briefly interrupts the abnormal electrical activity, allowing the heart’s natural pacemaker to re-establish a normal rhythm.

How is it performed?
The procedure is often combined with a Transoesophageal echocardiogram (TOE) to check for blood clots in the upper chambers of the heart before the shock is delivered. Cardioversion is performed under light anaesthesia or sedation, so the patient does not feel the shock.

What is the success rate of cardioversion?

The success varies with type of arrhythmia.  Success is defined as restoration of normal heart rhythm at the time of the procedure. 

• Atrial flutter:  90–95%
• Atrial fibrillation: 70–90%
   

What is the Long-term success (maintenance of normal rhythm)?

• At 1 year, about 40–60% of patients remain in normal rhythm without recurrence
• Success improves when combined with: 
  • Anti-arrhythmic medications 
  • Risk factor control (blood pressure, weight, sleep apnoea, alcohol intake) 
  • Early intervention (shorter duration of arrhythmia)