Ask the doctor
Q. I am scheduled for an electrical cardioversion for my atrial fibrillation. What should I expect?
A. Electrical cardioversion is a procedure to convert a fast or irregular heartbeat (such as what happens with atrial fibrillation, or afib) to a normal rhythm. Before the procedure, your cardiologist may recommend a special ultrasound test of your heart to check for blood clots. Cardioversion may dislodge any clots, which can be life-threatening. So if clots are found, the procedure may be delayed for a few weeks, so you can take blood-thinning medications to lower your risk of complications such as stroke.
Before the cardioversion, you can’t eat or drink for eight to 12 hours. You’ll receive intravenous medications through a vein in your arm to make you sleepy throughout the procedure. A nurse or technician will place patches called electrodes on your chest. Wires from the electrodes connect to a cardioversion machine. This machine (also called a defibrillator) records your heart rhythm and delivers low-energy shocks that help restore your heart to a normal, steady rhythm. After you’re sedated, the procedure only takes a few minutes. But you’ll stay in a recovery room for a few hours afterward and be monitored to make sure you don’t develop any complications. You’ll need to have someone drive you home.
The success rate is typically high for people with recent afib. But in some people, the abnormal rhythm returns within a few minutes or days. If that happens, you might need to have a repeat procedure or take medications for afib.
– Deepak L. Bhatt, MD, MPH
Editor in chief
Harvard Heart Letter