What is the success rate of electrical cardioversion?

As a medical professional with expertise in cardiology, I can provide you with an overview of the success rates of electrical cardioversion. Electrical cardioversion is a procedure used to restore normal heart rhythm in patients with atrial fibrillation (AFib) or atrial flutter (AFL). The success rate can vary depending on several factors, including the type of arrhythmia, the duration of the condition, the use of antiarrhythmic medications, and the patient's overall health. For atrial fibrillation, the immediate success rate of electrical cardioversion is relatively high, often ranging from 80% to 90%. However, it's important to note that the recurrence rate is also significant, with up to 50% of patients experiencing a return of AFib within a year. For atrial flutter, the success rate is typically higher and can be as high as 90% to 95% for the initial procedure. However, similar to AFib, there is a risk of recurrence. The use of antiarrhythmic medications both before and after the procedure can improve the success rate and reduce the likelihood of recurrence. These medications help to maintain the normal heart rhythm after cardioversion. It's also worth mentioning that the success rate can be influenced by the duration of the arrhythmia. Cardioversion is more likely to be successful in patients with paroxysmal (intermittent) arrhythmias compared to those with persistent (longer-lasting) or permanent arrhythmias. In summary, while electrical cardioversion has a high immediate success rate for restoring normal heart rhythm, the long-term success in preventing recurrence is less predictable and depends on various patient-specific factors.

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.