Lead Extraction
Lead Extraction (Removal of Pacemaker and Defibrillator Leads from the Heart)
Lead extraction means using specific tools to remove redundant (no longer needed) or infected pacemaker or defibrillator leads from a patient’s heart. Sometimes leads can be removed simply by gentle traction (if they haven’t been implanted for a long time), however, if leads have been in the body for a long time then scar tissue will develop around the leads making them harder to remove. Tools such as locking stylets can be placed down the centre of the leads to provide extra support and Teflon/plastic sheaths or sheaths with fine blades for cutting can be passed over the leads to break up this surrounding scar tissue. Uncommonly, if leads can’t be removed via the vein that they were implanted through then open-heart surgery may be required to safely remove the leads.
Reasons for Lead Extraction
The most common reason that leads need to be removed is because an infection has developed on the pacemaker or defibrillator or on the leads themselves. In general, infections are not possible to eradicate if bacteria are attached to foreign material within the body and if the infection is within the bloodstream this can represent a life-threatening situation if the leads are not removed. Less commonly leads may need to be removed if they are associated with an occluded vein resulting in significant symptoms, to provide room for new leads to be implanted or if the leads themselves are causing cardiac arrhythmias or otherwise untreatable discomfort for the patient.
A Lead Extraction Procedure
Lead extraction is usually performed under general anaesthesia with careful cardiac monitoring and it must be done in the setting where urgent open-heart surgery can be performed if necessary. Most extractions will take between one and four hours and all leads can be removed with a percutaneous approach (without the need for open-heart surgery) around 97% of the time. A number of factors are associated with a more difficult extraction but the most important one is the length of time that the leads have been implanted for. The mortality risk with a lead extraction procedure is around 0.5-1% on average, however, this is largely dependent upon how unwell a patient is prior to the procedure and to some extent the equipment that is needed to remove the leads. The chance of a potentially serious complication occurring with a lead extraction is 3-4% and this could include the need for urgent open-heart surgery due to major bleeding (1-2%), stroke, blood clots in the veins of the arm, chest or lung, or injury to the lung.
If the lead extraction was performed due to an infection on the leads or device then it is common for the patient to have a period of intravenous antibiotics to completely eradicate the infection before a new pacemaker or defibrillator is implanted. For further questions you can contact Hunter Heart on 02 4952 3900 or cardio@hunterheart.com.au
Above is a diagram showing how lead extraction might be performed in a patient with two pacemaker leads in the heart. An incision is usually performed through the previous pacemaker scar so that the old pacemaker can be removed and any scar tissue in the wound itself is dissected away from the pacing leads. In this case the leads could not be removed by retracting the screw at the tip and gently pulling on them so a Teflon lead extraction sheath (shown in green) is passed down over each lead in turn and through the vein to free the leads from surrounding scar tissue and allow them to be completely extracted from the heart. If the lead extraction was performed due to infection then a new pacemaker is usually implanted when the infection has completely resolved.
The picture above is an X-Ray that was taken during a Lead Extraction procedure. The patient had an infection on their defibrillation lead and it therefore needed to be removed. In this case a mechanical extraction sheath (shown) was passed over the lead to free it up from surrounding scar tissue and enable it to be completely removed so the infection could be cured.