Today, implantable ECG monitors are very small devices that are inserted under the skin of the chest at the level of the heart during a very simple procedure. The implantation is performed under local anesthesia, most often on an outpatient basis. It takes a few minutes and consists of sliding the device under the skin, in a sterile environment. The skin is then closed with sutures or surgical glue. The outcome of the intervention is generally very simple: the pain remains very minimal and complete closure of the skin occurs in a few days after the implantation. It is very important to understand the operation of the device before leaving the implantation center in order to be able to use it to the best of its ability.