How can a patient with a history of heart conditions such as arrhythmias, heart failure, or cardiac arrest determine if they have an Implantable Cardioverter-Defibrillator (ICD)?

How to Determine if You Have an ICD

If you have a history of heart conditions, you can determine whether you have an ICD by checking for a visible scar and palpable device in your upper chest area, reviewing your medical records or manufacturer's identification card, or obtaining a chest X-ray that will show the device and its leads. 1

Physical Self-Examination

Check your upper chest area (usually left side, below the collarbone) for:

• A horizontal or curved surgical scar, typically 2-4 inches long 1
• A firm, rectangular bump under the skin that you can feel when pressing gently on your chest 1
• The device is about the size of a small pager or deck of cards and sits just beneath the skin 1

Review Your Medical Documentation

Look for the following records:

• A manufacturer's identification card that should have been given to you at implantation—this card specifies the device type, model, and manufacturer 1
• Hospital discharge summaries or operative reports mentioning "ICD implantation" or "implantable cardioverter-defibrillator" 1
• Cardiology clinic notes documenting device interrogations or follow-up visits 1

The manufacturer's card is the most definitive non-invasive way to confirm device presence and should be carried with you at all times. 1

Imaging Studies

If physical examination and records are unavailable:

• A chest X-ray will clearly show the ICD generator (pulse generator) in the upper chest and the leads extending into the heart 1
• Most current ICDs have an X-ray code visible on imaging that identifies the manufacturer 1
• An electrocardiogram (ECG) may show pacing spikes if the device is actively pacing, though this is not always present 1

Contact Healthcare Resources

If uncertainty remains after the above steps:

• Contact your cardiologist's office or the hospital where you received cardiac care—they maintain records of all device implantations 1
• Call the manufacturer directly using databases that track implanted devices by patient information 1
• Request consultation with a cardiac electrophysiologist who can perform device interrogation 1

Common Clinical Scenarios Suggesting ICD Presence

You are more likely to have an ICD if you have:

• A history of cardiac arrest or life-threatening ventricular arrhythmias (secondary prevention indication) 2, 3, 4
• Severe heart failure with ejection fraction ≤30-35% despite optimal medical therapy (primary prevention indication) 5, 3, 4
• History of ventricular tachycardia or ventricular fibrillation 2, 3
• Certain inherited heart conditions like hypertrophic cardiomyopathy, arrhythmogenic right ventricular cardiomyopathy, Brugada syndrome, or long QT syndrome 3

Approximately 58% of ICD patients receive shocks from their device during follow-up, which would be a definitive indicator of ICD presence. 2

Important Caveats

Do not confuse an ICD with a pacemaker:

• Both create a visible chest bulge and scar, but ICDs are typically slightly larger 1
• ICDs can function as pacemakers but also deliver high-energy shocks for life-threatening arrhythmias 1, 3
• Only device interrogation or manufacturer documentation can definitively distinguish between the two 1

If you are uncertain and require surgery or medical procedures:

• Always inform healthcare providers that you may have a cardiac device, as electromagnetic interference from surgical equipment can affect device function 1
• Failure to identify a device preoperatively has led to adverse outcomes including device inhibition and asystole 1