Table of ContentsView AllTable of ContentsEP Study NecessityRisks and ContradictionsBefore the StudyDuring the StudyAfter the StudyWhat Results Mean
Table of ContentsView All
View All
Table of Contents
EP Study Necessity
Risks and Contradictions
Before the Study
During the Study
After the Study
What Results Mean
An electrophysiology study (EP study or EPS) uses the heart’s electrical signals to diagnose abnormal heartbeats or heart rhythms (arrhythmia).
During EPS, three to five catheters (flexible wires) pass through intravenous (IV) wires (also called sheaths) inserted into the groin or neck.A healthcare provider then guides the electrodes to the heart with the aid of a video screen.
The person is sedated but awake during the study. An electrophysiology study is painless, though there is some pressure where the catheters enter the groin or neck.
This article discusses what an electrophysiology study looks like, risks or potential complications, how to prepare for an EP study, what happens afterward, and how the results are interpreted.
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Why You Are Having an Electrophysiology Study
An EP study is usually advisable when noninvasive testing methods, like an electrocardiogram (anEKG) or Holter monitor (a pocket-size, battery-operated heart-monitoring device), don’t provide answers. Electrophysiology studies can help determine:
Electrophysiology studies are usually ordered when noninvasive procedures cannot find the root of an issue. There are some risks and contraindications associated with the test.
Electrophysiology Study Risks
Though it is largely safe, EP studies can include some risk of side effects, including:
Accuracy of ElectrophysiologyEP studies can be more specific in identifying the exact cause of arrhythmia, at a rate of 75% to 95%. They are most accurate for determining the cause of arrhythmias.
Accuracy of Electrophysiology
EP studies can be more specific in identifying the exact cause of arrhythmia, at a rate of 75% to 95%. They are most accurate for determining the cause of arrhythmias.
Before the Electrophysiology Study
To prepare for an EP study, you will likely be instructed to do the following:
How Long It Takes
An EP test takes about one to four hours, which includes time for sedative and local anesthetic medications, shaving the area where the electrodes are inserted, conducting the test itself, and removing the IVs after the results are recorded.
Location
An EP test is likely to take place in an EP lab or a catheterization lab (cath lab), where you’ll lie on an X-ray table next to monitors. After the procedure, you will be taken to a recovery room for one to three hours.
Food and Drink
Before undergoing an EP study, usually you’ll be instructed to avoid food for six to eight hours.
Cost and Health Insurance
The cost of an EP study can depend on the subject’s insurance coverage, but most plans cover the procedure and any other noninvasive tests that diagnose arrhythmia. Check with your insurance plan to determine your out-of-pocket costs.
What to Bring
Before undergoing an EP study, you should bring a list of current medications and supplements to your healthcare provider. This is to determine which are to be avoided right before the test. On the day of an EP study, bring to the testing site any hearing or vision aids you normally wear.
Other Considerations
Considering the sedative medications that precede an EP study, arranging transportation to and from your healthcare provider’s office is an important consideration.
What to Expect During an EP Study
The following is some of what you can expect before, during, and after an EP study.
Before the Test
You will likely need to sign a consent form before undergoing an EP study.
After giving your consent, a nurse (and/or anesthesiologist) will likely do the following:
What You Will Feel
Throughout your EP study, you’ll likely feel:
EP Study Procedure
The EP study will then proceed with the following steps:
Post-Test Recovery
An EP study take about one to four hours, after which you will likely go to a recovery room for four to six hours. It is advisable to remain still during recovery time. If you experience pain or bleeding, contact a nurse immediately.
After about six hours, you will likely be permitted to eat and then take any medications you have been prescribed or have been taking.
After an Electrophysiology Study
Avoiding driving during the 24 hours after an EP study is advisable. However, normal activities can resume the next day.Refraining from picking up anything that weighs more than 10 pounds is also advisable. You can also remove any dressings for wounds the next day.
Managing Side Effects
Side effects of an EP study can include:
The following side effects require medical attention:
Post–EP Study: Emergency Side EffectsIf any of the following occurs after your EP study, call 911 immediately:Uncontrolled bleeding at insertion sitesSymptoms ofstrokeorheart attack, like chest pain, light-headedness, or heavy breathingSwelling at puncture sites
Post–EP Study: Emergency Side Effects
If any of the following occurs after your EP study, call 911 immediately:Uncontrolled bleeding at insertion sitesSymptoms ofstrokeorheart attack, like chest pain, light-headedness, or heavy breathingSwelling at puncture sites
If any of the following occurs after your EP study, call 911 immediately:
Interpreting EP Study Results
When the results of an EP study are available can depend on your healthcare provider, and you will likely require a future appointment to discuss them.
Electrophysiology results can look like drawings of lifeline measurements. The results can provide insight into aspects of irregular heart rhythms, including:
Undergoing a repeat EP study (such as when following up on a pacemaker, for example) is possible; however, you should discuss the risks associated with the procedure with your healthcare provider.
Other tests for arrhythmia can help clarify diagnoses, including for longer-term conditions and other areas of the heart and body. For example:
If your EP study indicates a problem, your healthcare provider might perform acatheter ablationto remove any damaged tissue from the heart during the EP study itself.
Other treatments might include:
An EP study can help pinpoint the exact location of an arrhythmia and provide a treatment plan. However, if you have doubts about your diagnosis, do keep an open dialogue with your healthcare provider about other available tests.
Requesting a copy of EP study results for a second opinion may also help.
Summary
An electrophysiology (EP) study uses catheters with cameras to determine the location and cause of arrhythmia. During the study, IVs create punctures, and catheters are then inserted and guided with the help of video monitors. An EP study can come with some risks, including tissue damage. However, the test largely is safe.
Patients are given anesthesia and calming medications, and most people stay awake throughout them.
During an EP study, you might experience pressure where the catheters are inserted. After your healthcare provider has inserted the catheters, they may apply an electrical current to make the heart beat faster. They will then measure and record the electrical signals in response.
14 SourcesVerywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read oureditorial processto learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.Garden City Hospital.Electrophysiology studies.UCSF Health.Electrophysiology procedure.American Heart Association.Electrophysiology studies.MedlinePlus.Intracardiac electrophysiology study (EPS).Johns Hopkins Medicine.Electrophysiological studies.American Heart Association.Ablation for arrhythmias.American Heart Association.Implantable cardioverter defibrillator (ICD).Stanford Medicine.Electrophysiology study–EPS.UCSF Health.Preparing for an EP study.Abbot.Abbott Coding Guide.Abbott, 2023.British Heart Foundation.Electrophysiological (EP) study.Koulouris S, Cascella M.Electrophysiologic study interpretation. In:StatPearls. StatPearls Publishing; 2022.Das M, Wynn GJ, Morgan M, et al.Recurrence of atrial tachyarrhythmia during the second month of the blanking period is associated with more extensive pulmonary vein reconnection at repeat electrophysiology study.Circ: Arrhythmia and Electrophysiology. 2015;8(4):846-852. doi: 10.1161/circep.115.003095American Heart Association.Prevention and treatment of arrhythmia.
14 Sources
Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read oureditorial processto learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.Garden City Hospital.Electrophysiology studies.UCSF Health.Electrophysiology procedure.American Heart Association.Electrophysiology studies.MedlinePlus.Intracardiac electrophysiology study (EPS).Johns Hopkins Medicine.Electrophysiological studies.American Heart Association.Ablation for arrhythmias.American Heart Association.Implantable cardioverter defibrillator (ICD).Stanford Medicine.Electrophysiology study–EPS.UCSF Health.Preparing for an EP study.Abbot.Abbott Coding Guide.Abbott, 2023.British Heart Foundation.Electrophysiological (EP) study.Koulouris S, Cascella M.Electrophysiologic study interpretation. In:StatPearls. StatPearls Publishing; 2022.Das M, Wynn GJ, Morgan M, et al.Recurrence of atrial tachyarrhythmia during the second month of the blanking period is associated with more extensive pulmonary vein reconnection at repeat electrophysiology study.Circ: Arrhythmia and Electrophysiology. 2015;8(4):846-852. doi: 10.1161/circep.115.003095American Heart Association.Prevention and treatment of arrhythmia.
Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read oureditorial processto learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
Garden City Hospital.Electrophysiology studies.UCSF Health.Electrophysiology procedure.American Heart Association.Electrophysiology studies.MedlinePlus.Intracardiac electrophysiology study (EPS).Johns Hopkins Medicine.Electrophysiological studies.American Heart Association.Ablation for arrhythmias.American Heart Association.Implantable cardioverter defibrillator (ICD).Stanford Medicine.Electrophysiology study–EPS.UCSF Health.Preparing for an EP study.Abbot.Abbott Coding Guide.Abbott, 2023.British Heart Foundation.Electrophysiological (EP) study.Koulouris S, Cascella M.Electrophysiologic study interpretation. In:StatPearls. StatPearls Publishing; 2022.Das M, Wynn GJ, Morgan M, et al.Recurrence of atrial tachyarrhythmia during the second month of the blanking period is associated with more extensive pulmonary vein reconnection at repeat electrophysiology study.Circ: Arrhythmia and Electrophysiology. 2015;8(4):846-852. doi: 10.1161/circep.115.003095American Heart Association.Prevention and treatment of arrhythmia.
Garden City Hospital.Electrophysiology studies.
UCSF Health.Electrophysiology procedure.
American Heart Association.Electrophysiology studies.
MedlinePlus.Intracardiac electrophysiology study (EPS).
Johns Hopkins Medicine.Electrophysiological studies.
American Heart Association.Ablation for arrhythmias.
American Heart Association.Implantable cardioverter defibrillator (ICD).
Stanford Medicine.Electrophysiology study–EPS.
UCSF Health.Preparing for an EP study.
Abbot.Abbott Coding Guide.Abbott, 2023.
British Heart Foundation.Electrophysiological (EP) study.
Koulouris S, Cascella M.Electrophysiologic study interpretation. In:StatPearls. StatPearls Publishing; 2022.
Das M, Wynn GJ, Morgan M, et al.Recurrence of atrial tachyarrhythmia during the second month of the blanking period is associated with more extensive pulmonary vein reconnection at repeat electrophysiology study.Circ: Arrhythmia and Electrophysiology. 2015;8(4):846-852. doi: 10.1161/circep.115.003095
American Heart Association.Prevention and treatment of arrhythmia.
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