Maria Grazia Bongiorni (Pisa, Italy) compares mechanical transvenous lead extraction vs. laser lead extraction approaches with supporting evidence from key randomised controlled trials in the field.
In the last few decades, the number of cardiovascular implantable electronic devices (CIEDs) has strikingly risen, leading to an increasing number of complications, ie. malfunction or infection. Since the first implantable pacemakers were first introduced in the 1960s, transvenous lead extraction techniques have been developed in order to treat lead complications. Accordingly, different tools and venous approaches have been gradually introduced in clinical practice.
Since fibrosis between implanted leads and the cardiovascular system represent the principal obstacle to transvenous lead extraction, the development of dedicated sheaths (tools used to dissects binding sites) represented a necessary point for the refinement of extraction techniques.
The mechanical polypropilene sheaths (Cook Vascular) that were first introduced in the market required manual advancement over the removing leads. Subsequently, powered laser sheaths, using mainly laser energy, were developed.
So far, three randomised controlled trials have been performed in this field. All of them have been designed to compare powered laser sheaths with mechanical approaches for lead extraction. PLEXES (Wilkoff BL et al, JACC 1999) was a randomised trial of lead extraction conducted in 301 patients with 465 chronically implanted pacemaker leads. The laser group patients had the leads removed with identical tools as the non-laser group with the exception that the inner telescoping sheath was replaced with the 12F excimer laser sheath (Spectranetics). Success rate, as indicated by complete lead removal, was 94% in the laser group and 64% in the non-laser group (p=0.001). Moreover, unsuccessful non-laser extraction was completed with the laser tools 88% of the time with a generally more contained extraction time in patients randomised to the laser devices. On the other hand, potentially life-threatening complications occurred in none of the non-laser and three of the laser patients, including one death (p=NS). Authors concluded that laser-assisted pacemaker lead extraction has significant clinical advantages over extraction without laser tools and is associated with significant risks. A limitation of the trial was the possibility of crossover between non-laser and laser groups. Since the laser group was allowed to use all the mechanical tools, this led to a bias of one-way crossover, causing a significant difference in success rate among the techniques. Moreover, the failure of the mechanical approach was motivated by signs of lead damage, which was an operator judgment, and 30 out of 75 of these leads were Telectronics Accufix leads (which were prone to deformation/rupture during traction).
The effectiveness of electrosurgical dissection sheath (EDS) systems in extracting pacemaker and ICD lead was recently evaluated (Neuzil P et al, Europace 2007;9:98‒104), showing effectiveness and safety similar to laser dilation. However, despite the relative cost-effectiveness of EDS guided extraction, this technique is currently less commonly used in comparison with laser.
Finally, transfemoral mechanical lead extraction and laser-guided upper vein extraction were also compared (Bordachar P et al, Circ Arrhythm Electrophysiol 2010;3:319‒323) in 101 patients who needed to have at least one lead older than four years. The two approaches obtained similar success (88.2 vs. 88.0 %) with three major complications (two in the laser arm and one in the standard arm) without deaths.
Based on these trials, powered sheaths were reported as more effective than mechanical sheaths. On the other hand, their use seemed to be associated with a higher incidence of major complications, and they are undoubtedly more expensive.
A meta-analysis of the last 15 years of experience in lead extraction was recently published (Diemberger I et al, Expert Rev Med Devices 2013;10:551‒573). Sixty-two studies on transvenous lead extraction were evaluated and 13,000 patients (69% men, mean age 64 years) with 20,000 leads (pacing 79%, ICD 17%, coronary sinus 4%) enrolled. Infection was the leading indication of extraction (55%). In the overall population, complete removal was 94%, major complications 1.7% and death rate 0.3%. The meta-regression analysis identified the following variables associated with worst outcome: patient age, presence of leads in situ for more than one year, presence of device infection and use of laser sheath. The use of laser sheath was associated with increased risk of major complications or death among the entire population (p=0.029) despite being associated with higher technical success of extraction (p=0.003).
In presence of infection—where a greater push for complete extraction is obviously searched—a greater technical success is obtained with mechanical extraction, while the laser approach seems to carry more complications. Possible explanations for the higher incidence of complications associated with laser extractions are: a) a decrease in venous wall stiffness after lasing (laser action + larger sized sheaths); b) the delivery of fixed amount of energy irrespective of the tenacity of binding sites; c) the absence of feedback about the force applied by the operator.
Different approaches have been adopted for transvenous lead extraction, and many centres have changed their approach with the introduction of new tools and techniques. The introduction of laser sheaths was probably one of the greatest changes in the lead extraction scenario, influencing authors’ opinions and attracting many of the non-extractors to the discipline. However, as with any innovation, despite the efficacy of the laser sheath it should not be considered the single pillar of the extraction strategy but should be included in a more complex approach.
Any technique can provide good results when properly performed by an experienced team. The first large prospective, multicentre, European controlled registry of consecutive (3,524) patients undergoing transvenous lead extraction procedures in European countries (ELECTRA), has shown that the sheaths were necessary to extract 63.5% of leads (36.3% mechanical, 19.2% laser, 7.7% Evolution, 0.1 EDS, other 0.2%). A further detailed analysis will give more information about success and complication rates using different tools and techniques for transvenous lead extraction in high- and low-volume centres.
Maria Grazia Bongiorni is director of the Arrhythmology Division, Cardiothoracic and vascular Department, University Hospital of Pisa, Italy