Defibrillator vs Pacemaker – What’s the difference?

Defibrillator vs Pacemaker – Overview

You may have heard about pacemakers and defibrillators that doctors often recommend to treat patients with heart problems.

These are used when the patient has a heart problem called arrhythmia. This cardiac condition causes your heart to beat slower or faster or beat with an irregular rhythm, depending on the kind of arrhythmia the patient has.

Though both these devices are designed to keep your heart beating regularly, they are vastly different compared to one another.

Let’s look at the differences between a defibrillator and a pacemaker.

Defibrillator vs Pacemaker

Defibrillator vs Pacemaker – What’s the difference

What is a Defibrillator?

A defibrillator is technically labeled “implantable cardioverter defibrillator” (ICD). This is a small device that is placed under your skin.

It consists of a computer that keeps track of your heart rate and rhythm. If the ICD detects a life-threatening rapid rhythm, it sends a shock to the heart to restore a normal rhythm. ICDs primarily address fast and potentially life-threatening arrhythmias.

Many ICDs have a built-in pacemaker function that can pace the heart if it beats too slowly.

Why do you need a Defibrillator?

You may need an ICD if you’re at risk of sudden cardiac death due to ventricular arrhythmias. You may also need to implant a defibrillator if you have suffered a cardiac arrest or heart attack, which causes your heart to stop beating altogether.

A defibrillator can save your life if your abnormal heart rhythm becomes too dangerous.

How is the Defibrillator Implanted?

The surgeon will advise you to take antibiotics before the implant surgery.

You may be asked to stop taking certain medications, but decisions about blood-thinning medications are made individually. You may be administered anesthesia so you do not feel any discomfort or pain.

The surgeon usually places the wires from the defibrillator device into a vein and connects them to your heart.

A small incision is made in the chest, and the device is implanted here. The surgeon will test the defibrillator to ensure it works well before concluding the surgery by suturing the incision.

What is a Pacemaker?

As the name suggests, a pacemaker is a small device that sends out electrical pulses to keep your heartbeat at a regular, steady rate and rhythm. This device is usually placed under the skin in the upper chest, quite close to the heart.

Pacemakers are primarily designed to correct bradycardia (slow heart rate); they do not “detect abnormalities in rate and rhythm” in the broad sense implied but rather provide pacing to maintain a normal heart rate.

Why do you need a Pacemaker?

Several conditions may require you to wear a pacemaker, such as:

  • Abnormally slow or uneven heartbeat, which has not been treated with other techniques.
  • A pacemaker may be needed after an ablation procedure if the procedure results in a heart rate that is too slow, not as a general consequence of all ablation procedures.
  • While medications can lead to a slow heart rate, pacemakers are typically prescribed for intrinsic heart rhythm abnormalities.

How is Pacemaker Implanted?

A pacemaker is implanted with a minor surgical procedure. The surgeon usually gives you a dose of antibiotics to prevent the risk of infection from the implanted device.

Similar to correction 4, this statement inaccurately conflates guidelines for fasting and medication adjustments. Decisions on blood thinners are individualized, and the patient is asked to fast.

Then, the surgeon will administer local or general anesthesia so you do not feel discomfort or pain while the implant surgery is underway.

The surgeon will make a small incision in the upper chest, close to the heart. The pacemakers’ wires, called ‘leads,’ are threaded through a blood vessel to the heart.

Then, the pacemaker itself is implanted just under the collarbone. It consists of a small computer and a battery.

Usually, the surgeon tries to implant a pacemaker on the side you don’t use most often. For instance, the pacemaker is implanted on the left side if you are right-handed.

The leads from the pacemaker connect to your heart. The charges allow the electrical signals to travel back and forth between the heart and the pacemaker.

These signals let the pacemaker’s computer know your heart rate. If the computer detects irregularity or a slowed or fast heartbeat, it sends an alert to the heart to resume beating at an average pace.


The defibrillator and pacemaker ensure that your heart beats at a normal, regular rhythm. These devices can help you to resume most of your normal daily activities, including exercising.

Follow the surgeon and doctor’s instructions before and after the implant surgery and attend all follow-up appointments to ensure a successful pacemaker or defibrillator implant.

See Also

American Heart Association AED Grants

AED Grants for Police Departments

AED Grants for Fire Departments

AED for Schools Grant Money

Grants for AED

Current Version
October 10, 2023
Updated By
Andrea Morales G.
March 20, 2024
Updated By
Daniyal Haider, MD

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