What Is an Implantable Cardioverter Defibrillator (ICD)?
When your heart rate is too fast for your heart to pump effectively,
we may recommend a procedure to place an implantable cardioverter
defibrillator (ICD). An ICD is an implantable electronic device that
continuously monitors your heart rate and slows it when it becomes too fast.
How does an implantable cardioverter defibrillator (ICD) work?
When your ICD senses an abnormal heart rhythm, it will deliver an
electrical shock to your heart to try to stop the fast rhythm. Your
physician can also program the ICD to "pace" your heart back
to a normal rhythm when it is going too fast. All ICDs have back-up
pacing for rhythms that are too slow. If the ICD senses a slow
heartbeat, it sends a signal to speed up.
Parts of an ICD
The implantable defibrillator includes a:
Pulse generator: This is the battery back and is
approximately half the size of a deck of cards. We implant it
beneath the skin of your left chest or abdomen. It is connected to
the lead system, which is connected to your heart.
Leads/electrodes: These are thin wires that connect your
heart to the device. The leads carry the signal from your heart
muscle to the pulse generator when your heart beats. If the
generator senses an abnormal rhythm, the lead delivers a shock back
to your heart.
An implantable cardioverter defibrillator (ICD) looks very similar
to a pacemaker,
except that it is slightly larger. Some devices combine a pacemaker
and ICD in one unit. Learn more about who can
benefit from an ICD.
Anti-tachycardia pacing (ATP)
The ICD has another type of treatment for certain fast rhythms
called anti-tachycardia pacing (ATP). When ATP is used, the ICD sends
a fast pacing impulse to correct the rhythm. After the shock is
delivered, a “back-up” pacing mode is used if needed for a short while.
Conditions treated with an ICD
We treat many heart arrhythmias with an ICD including atrial
fibrillation (or A-fib) and bradycardia. Learn more about conditions
we treat using ICD.
ICD procedure: What to expect
You may have many questions about why you need an ICD and what the
procedure will be like. Your team is always available to discuss your
procedure with you in detail. We have also compiled some helpful