Treatment: ICD implantation – insertion of an implantable cardioverter-defibrillator

A defibrillator or ICD (implantable cardioverter defibrillator) is an advanced pacemaker. It functions like a normal pacemaker, maintaining a minimum heart rate (pulse), but at the same time it can treat life-threatening rapid heart rhythm disturbances.

It works by delivering either an electrical shock that briefly blocks all electrical impulses in the heart, or rapid electrical impulses that interrupt an episode.

If you have not lost consciousness before the ICD delivers a shock, you may feel the shock as a strong ‘blow to the chest’. In most cases, the ICD will be programmed to wait long enough before delivering a shock, so that you are unconscious or close to being so.

If you have experienced life-threatening cardiac arrhythmia, or if you are at an increased risk of developing one, we would recommend implanting an ICD (defibrillator).

If you have reduced pumping function (heart failure), we will often recommend implanting a special type of ICD with three electrodes – a 'biventricular ICD'.

Before the treatment, you will receive a letter informing you about fasting and medication and what to bring with you in connection with your treatment.

You should expect to be admitted for one day, unless you are told otherwise. On the day of the procedure, you will have a consultation with the cardiologist. Relatives are welcome to attend.

You will also need to have blood tests and an ECG, and your blood pressure will be taken.

Before the operation begins, various preparations will take approximately half an hour. We will insert a small plastic tube (Venflon) into your hand through which we can administer medication, including antibiotics to prevent infection.

The operation takes one to two hours, although the BiV implantation may take up to three hours. All implantations are carried out under local anesthetic, which is administered into the skin in the chest area below the left collarbone, where the ICD device is to be inserted. You may experience a brief tightening sensation when the local anesthetic is injected.

Under X-ray guidance, the cardiologist then guides the electrodes through a blood vessel to the heart.

The electrodes are then connected to the ICD device, which is surgically implanted under the skin in a 'pocket'.

To ensure that the device is working as intended, you will then be briefly anesthetized, and the ICD device’s shock function will be tested. In rare cases where the shock cannot restore a normal rhythm, we restore the normal rhythm by delivering a shock externally to the chest, and then an additional electrode is implanted under the skin from the device to the left side of the chest.

If you need it during the operation, we can administer further painkillers or sedatives.

Once you are back in your ward, we will check your dressing. You are welcome to eat and drink, and you can get up when you feel ready.

Your heart rhythm will be monitored until the following day, at which point we will check that the ICD is working correctly.

If you experience pain in the wound, you will be offered painkillers.

The following morning, you will be seen by the specialist who performed your operation. He will carry out a brief test of the ICD device to ensure that everything is working as it should. This is done using data equipment, and a special probe (programming head) is placed on the skin over your ICD pocket, allowing us to communicate with the device and check the system.

If the ICD device is working satisfactorily, you can then go home. We expect you to be discharged after breakfast at around 8.30 am.

You can have shower baths from the day after the operation, as you will have a waterproof plaster covering the wound. This should be completely removed four to five days after the operation.

The sutures in the wound are dissolvable. If the ends of the sutures have not fallen out after about ten days, you can carefully cut them off yourself.

If you experience pain at the wound site, you can take painkillers such as Paracetamol.

You must always keep an eye on the wound. If it becomes red, swollen or tender, which may be a sign of infection, you must contact us or your GP.

Outpatient appointments at the pacemaker clinic

Follow-up appointments at the pacemaker/ICD outpatient clinic can take place either at our clinic or at a public hospital closer to your home. You can decide this yourself, but we recommend that your first follow-up appointment takes place at our clinic.

Your first outpatient check-up at our pacemaker clinic takes place after one to two months, and the date will be agreed before you go home.

Future check-ups will then take place every six months or annually.

The purpose of the outpatient visits is to check that the ICD device is functioning as intended, as well as to assess the condition of the electrodes and the battery life (six to eight years). Once it is agreed that the time has come for a replacement, only the device itself is replaced, while the electrodes are usually reused.

In addition to these check-ups, many ICD models have a built-in safety feature: they emit a beep or vibration to indicate that a check-up is required soon, due to problems with either the battery capacity or the condition of the electrodes.

ICD card

After approximately two months, you will be sent the original international ICD card. You must always carry the card with you and show it to doctors, dentists, physiotherapists and at airports.

If the ICD device delivers a shock

If you feel one or two shocks from the ICD device and are otherwise feeling well, please contact the pacemaker outpatient clinic at your local hospital or Privathospitalet Mølholm on the following working day. We will usually arrange for you to come in for a read-out of the ICD device so that we can assess whether further fine-tuning is required.

If you receive several shocks in succession, or if you feel unwell after a shock, you should call emergency services (112/999/911) so that you can be taken to the nearest hospital. The hospital may then contact the cardiologist on duty at Privathospitalet Mølholm.

Physical activity

For the first one to two months after the device is implanted, you should avoid doing any very strenuous physical work. You should also avoid hanging from a horizontal bar with your arms outstretched, as this places significant strain on the electrode in the ventricle.

It is important that you use both arms normally right from the start.

After your first outpatient check-up, you can resume your normal activities without having to consider the ICD device. You are welcome to take part in sports. However, to protect the skin over the device, we advise against contact sports such as boxing. Scuba diving is also not recommended.

What you should be aware of

TENS (transcutaneous electrical nerve stimulation) and shortwave therapy, as used in physiotherapy, should be avoided as they may interfere with the electronics in the ICD device.

You can pass through anti-theft alarms, such as those at shop exits, but you should ideally not stop within one meter of them.

Strong magnetic fields, such as those produced during an MRI scan, must be avoided.

Airport metal detectors will often detect the ICD device, so you should present your ICD card. Security staff will usually prefer you to walk around the detector. However, walking through the detector will not damage the ICD device.

Welding: You should avoid working with electric spot welding (arc welding).

Emotional reactions: It is normal to experience emotional reactions following hospitalization, which are often shared by close family members. Some people feel anxious or unsettled, while others experience mood swings. Talking to others — family, friends or Patients associations — about your feelings can provide great support in such situations.

Driving and ICDs

See the following link: https://www.nbv.cardio.dk/korekort

The sensation of the electrical shock can differ from person to person. Some people describe it as a blow to the chest. If you are in physical contact with others when the shock occurs, they will not receive it themselves but will naturally sense it.

The overall risk of significant complications is less than 5%.

When the electrode is inserted, there is a risk of puncturing the lung, which can lead to a build-up of air or blood. This usually resolves within a few days, but if it does not, it may be necessary to insert a drain.

If a catheter pierces the heart wall, it can cause bleeding into the pericardial sac. This blood is usually removed by inserting a syringe into the pericardial sac. If this is not possible, emergency operation may be required.

In rare cases, the electrode may move within the ventricle. This can result in malfunction, necessitating repositioning of the electrode.

After the operation, a blood clot may form at the surgical site. This can cause swelling and tenderness, but it usually resolves on its own. In rare cases, the blood clot must be drained by means of a minor surgical procedure.

Despite preventive treatment against wound infection, this complication can still occur in rare cases.

During BiV implantations, inserting the third electrode into the blood vessel behind the left ventricle can be difficult, which is why this procedure takes longer. In four out of 100 operations, it is not possible to insert the third electrode.

Occasionally, the ICD device 'misinterprets' the heart rhythm and delivers a shock even when there is no life-threatening rapid heart rhythm. This can generally be remedied by reprogramming the device.