Cardioversion - Cardiovascular Associates of Maryland
What is Cardioversion?
Cardioversion is a medical procedure used to convert an abnormal heart
rhythm to a normal rhythm by giving the heart a brief electrical shock.
The electric shock causes the heart cells to contract simultaneously,
disrupting the abnormal rhythm and allowing the heart to restore a
normal heart beat.
Why is it needed?
Cardioversion is most commonly used to treat persistent atrial
fibrillation or atrial flutter when anti-arrhythmic medication alone
does not correct the rhythm disturbance. Patients may need to continue
their anti-arrhythmic medication after the procedure to prevent the
abnormal heart rhythm from returning.
How is it performed?
Cardioversion is performed as an outpatient procedure in the hospital.
Adhesive patches with electrodes are applied to the chest and sometimes
the back. The electrode patches are connected by a cable to a
defibrillator, which delivers the electric shock. Patients will be
given an IV medication for sedation to prevent any discomfort with
cardioversion during the procedure.
After the patient is sedated, the physician will charge the
defibrillator and deliver the electric shock to the heart muscle. The
electric shock may be repeated with a higher energy level if the first
attempt does not correct the abnormal rhythm. The sedative used during
the procedure is effective at eliminating any discomfort for the patient
but short-acting so patients are typically able to leave the hospital
about one to two hours after the procedure.
How do I prepare for the procedure?
There are several ways that you can prepare for the procedure, including:
- Do not eat or drink eight hours prior to the procedure.
- Do take your regularly scheduled medication with a small sip of water.
- If you are diabetic, talk to your physician about insulin or other medication dosing prior to the procedure.
- Do not apply lotion or ointment to your chest or back since it may interfere with the adherence of the patches.
- Because of the sedation used, you will need to arrange for a
ride home from the hospital. You should not drive or operate heavy
machinery for the remainder of the day.
- You may experience minor skin irritation where the patches were
applied. This can be treated with a topical steroid ointment to reduce
the discomfort.
Note: Sometimes a trans-esophageal echo
(TEE) is required prior to cardioversion to check for blood clots in the
heart. This is a short procedure in which your throat is anesthetized
with a spray. A small echo probe is inserted into the esophagus and
positioned behind the heart. The probe is removed after pictures have
been taken. If a clot is present, the cardioversion will be delayed for
several weeks. Your doctor will inform you if a TEE is necessary prior
to your procedure.