What Happens When A Defibrillator Goes Off? | How ICDs Work To Keep You Alive

Aug 15, 2021

The thought of a defibrillator going off can be worrying, especially if you’ve had one implanted due to the risk of electrical malfunction within the heart. But you might not know precisely what happens when an ICD, or implantable cardioverter-defibrillator, goes off. What happens? How does it know when to go off, and what should you do afterward?

In this post, we’ll look into how ICDs work, how they determine when a defibrillation shock is necessary, and what you can do to find out more about how your ICD behaves.

How An ICD Works: A Modern Medical Marvel

Pacemakers have been in use for several decades as part of implantable cardiac resynchronization therapy (CRT.) These devices can detect when the heart is beating too slowly (bradycardia) or too fast (tachycardia) and can send small, corrective pulses of electricity to critical centers in the heart that correct the rhythm of the heart and bring it back to normal. They do this automatically, without any intervention from the patient.

An ICD, however, has an additional trick up its sleeve. Short for implantable cardioverter-defibrillator, an ICD performs pacemaker duties and relieves heart rhythm disturbances to restore proper blood circulation, just like a pacemaker. They do this using multiple algorithms that detect how the heart is pumping, the electrical impulses that synchronize the pumping chambers, and whether the current state is optimum for the patients’ needs.

However, the heart can experience a severely abnormal rhythm, become unsynchronized, or experience fibrillation. Fibrillation is a weak, quivering, and rapid contraction of one or more chambers of the heart. In the case of ventricular fibrillation, the heart cannot pump blood at all and goes into cardiac arrest, leading to death if defibrillation doesn’t happen.

This is where the ICD comes in. Sensing danger, it delivers a powerful shock to the heart to restart it and provokes it into resuming a normal rhythm. Effectively, an ICD can save your life. But what does it feel like when a defibrillator goes off?

When A Defibrillator Goes Off: Shocking, To Say The Least

Naturally, as you’d expect, there is pain involved when you deliver a shock to the heart. Some patients describe it as being hit by lightning, walking into a lamppost, or being kicked in the chest by a horse. Sometimes, a defibrillator might need to shock the heart multiple times to restore a normal heart rhythm. Some patients also describe seeing a flash of light, with patterns sometimes resembling lightning.

There’s no denying that the possibility of receiving a shock can be nerve-wracking. Still, you can rest with the knowledge that the ICD is listening to your heart 24/7, monitoring closely for any abnormalities, and can step in at any time to correct them. Whether the heart requires a gentle prod or a more powerful persuasive technique, it knows what to do and does it automatically.

Better than that, every event and action taken by the ICD is reported remotely to your doctor. This can allow doctors to predict when an event might happen before it does.

Conclusion: Your Doctors Are With You

Thanks to modern advances in technology, integrated wireless communications built into the ICD can report detailed information to your healthcare provider. This happens using transmitter units that sit by your bedside, talking to your ICD wirelessly. They can even be battery-powered, portable, and pocketable – about the size of a smartphone. So, your doctors can keep an eye on you no matter where you are, seeing exactly what’s going on. This gives patients the confidence to trust their device, their heart, and their doctor. And so, they can enjoy a better quality of life.

Octagos Health provides remote event monitoring software solutions for cardiac patients and providers. For a demonstration or any questions, give us a call today at (281) 769-8733.