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Electrophysiologic Testing

By

Thomas Cascino

, MD, MSc, Michigan Medicine, University of Michigan;


Michael J. Shea

, MD, Michigan Medicine at the University of Michigan

Reviewed/Revised Dec 2023
VIEW PROFESSIONAL VERSION
Topic Resources

Electrophysiologic testing measures the heart's electrical activity through wire electrodes inserted into all 4 heart chambers.

The Conduction System
VIDEO

iIn people in whom an arrhythmia is already documented or is highly suspected, electrophysiologic testing is used to define precisely the abnormal heart rhythm, determine its cause, and guide treatment. A doctor may intentionally provoke an abnormal heart rhythm during testing to find out whether a particular medication can stop the disturbance or whether an operation will help by eliminating abnormal electrical connections within the heart. If necessary, a doctor can quickly restore a normal rhythm with a brief electrical shock to the heart (cardioversion Cardioversion-Defibrillation There are many causes of abnormal heart rhythms (arrhythmias). Some arrhythmias are harmless and do not need treatment. Sometimes arrhythmias stop on their own or with changes in lifestyle,... read more Cardioversion-Defibrillation ). Although electrophysiologic testing is an invasive procedure and an anesthetic is required, the procedure is safe. The risk of death is 1 in 5,000. This procedure usually takes 1 to 2 hours.

How electrophysiologic testing is done

Testing is done in the hospital. After injecting a local anesthetic, a doctor inserts a catheter with tiny electrodes at its tip through a needle puncture of a vein in the groin, arm, or neck. The catheter is threaded through the major blood vessels into the heart chambers, usually using fluoroscopy (a continuous x-ray procedure) for guidance. The catheter is used to record the electrocardiogram (ECG) from within the heart and to identify the precise location of the electrical conduction pathways.

Radiofrequency ablation Destroying Abnormal Heart Tissue (Ablation) There are many causes of abnormal heart rhythms (arrhythmias). Some arrhythmias are harmless and do not need treatment. Sometimes arrhythmias stop on their own or with changes in lifestyle,... read more is sometimes done during the procedure and uses heat generated by the radio waves to destroy any abnormal electrical connections in the heart and prevent the person from having further arrhythmias without the need for ongoing medication therapy.

Cryoablation is similar to radiofrequency ablation but uses freezing rather than heat to destroy any abnormal electrical connections.

Radiofrequency Ablation
VIDEO
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