2 The procedure
2.1.1 This procedure is used to remove pacemaker leads that have been in place for a few months. Pacemaker leads may need to be removed or changed if they malfunction, cause heart rhythm problems or become infected. If the leads have been in place for more than a few months they can become tightly attached by scar tissue to the heart and to the veins through which they pass, making removal difficult and risky. This procedure may also be used to remove defibrillator leads.
2.1.2 The conventional technique for removing pacing leads involves inserting locking stylets and telescoping sheaths around the pacing leads to separate them from the surrounding scar tissue. If this fails, open chest surgery may be required. Alternatively, in some cases, the leads may be detached from the pacemaker unit and simply left inside the patient.
2.2.1 Laser sheaths are similar to standard extraction sheaths, but vaporise rather than tear the scar tissue surrounding the pacing leads. The use of laser sheaths involves passing a double-layered sheath over the pacing leads. The inner layer of the sheath is made from fibre-optic material that transmits a laser beam; the outer layer is more rigid. The double-layered sheath is passed slowly over the lead and laser energy vaporises the scar tissue around the lead as the sheath is advanced over it. When scar tissue has been vaporised up to a point near the heart, the more rigid outer sheath is advanced to provide countertraction for removal of the pacing lead.
2.3.1 In the studies reviewed, complete lead removal ranged from 89% (596/671 leads) to 98% (44/45 leads). In a randomised controlled trial, complete lead removal was 94% (230/244 leads) for patients in the laser group and 64% (142/221 leads) for patients in the non-laser group. In the same study, mean operation time per lead was 11 minutes in the laser group compared with 15 minutes in the non-laser group (p < 0.04). For more details, refer to the Sources of evidence section.
2.3.2 The Specialist Advisors had no concerns about the efficacy of this procedure. They considered it to be at least as efficacious as, and probably more efficacious than, standard techniques.
2.4.1 In a randomised controlled trial, 3 of 153 patients randomised to laser sheath removal required subsequent surgery (two patients required a thorocotomy and one patient required a chest tube). One patient later died after a cardiac tamponade, but this was not directly related to the use of laser energy. In the largest case series, major complications (defined as cardiac tamponade, haemothorax, pulmonary embolism, lead migration and death) were observed in 2% (31/1684) of patients, and 1% (13/1684) of patients died in hospital. For more details, refer to the Sources of evidence section.
2.4.2 The Specialist Advisors considered the complications of laser sheath removal of pacing leads to be similar to those of standard extraction techniques. They commented on the small risk of cardiac tamponade caused by rupture of major veins or the myocardium, and noted that this could result in the need for emergency surgery and, in some cases, cause death.