When Danish footballer Christian Eriksen collapsed during a friendly match recently, many people would have been surprised to see the footballer walk off the pitch after regaining consciousness.

The event brought back memories of Eriksen’s cardiac arrest during the delayed Euro 2020 tournament in 2021. On that occasion, he required emergency treatment on the pitch.

After the incident, Eriksen was fitted with an implantable cardioverter defibrillator (ICD). It’s thanks to this device that he is now recovering at home. The footballer even posted on social media that his ICD “did exactly what it was designed to do: protect me when I needed it”.

Although details of this latest incident are still emerging, ICDs – however effective – do not make someone immune to symptoms, blackouts or future medical problems.

What is an ICD and how does it work?

An ICD is a small pacemaker-like device designed to protect people at risk of dangerous heart rhythm disturbances. These abnormal rhythms can stop the heart from pumping enough blood around the body and, if left untreated, may lead to cardiac arrest.

The ICD is implanted under the skin below the collarbone and connected to the heart by one or more thin leads. It continuously monitors the heartbeat and can respond within seconds if a........

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