The ICD detects life-threatening, rapid heartbeats. If such a heartbeat (arrhythmia) occurs, the ICD quickly sends an electrical shock to the heart to change the rhythm back to normal.
An ICD is most often placed in people who are at high risk of sudden death from dangerous arrhythmias, such as ventricular tachycardia or ventricular fibrillation.
CARDIOVERSION USING DRUGS (PHARMACOLOGIC)
Cardioversion can be done using drugs that are taken by mouth or given through an intravenous line (IV). It can take from several minutes to days for this treatment to work. If you are given drugs for cardioversion in a hospital, your heart rate will be regularly checked.
Cardioversion using drugs can be done outside the hospital. This is most often done for people with atrial fibrillation that comes and goes. However, you will need to be closely followed-up by a cardiologist.
As with electrical cardioversion, you may be given blood thinning medicines to prevent blood clots from forming. Clots that leave the heart can cause a stroke.
Complications of cardioversion are uncommon, but may include:
Allergic reactions to the medicines used
Blood clots that can cause a stroke or other organ damage
Bruising, burning, or pain where the electrodes were used
Worsening of the arrhythmia
People who perform external cardioversion may be shocked if the procedure is not done correctly. This can cause heart rhythm problems, pain, and even death.
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Michael A. Chen, MD, PhD, Assistant Professor of Medicine, Division of Cardiology, Harborview Medical Center, University of Washington Medical School, Seattle, Washington. Also reviewed by David Zieve, MD, MHA, Bethanne Black, and the A.D.A.M. Editorial team.