Yes we can! But should we? Lead extraction for superfluous pacemaker and implanted cardioverter-defibrillator leads

In the current issue of Europace , Kennergren et al.1 reported the results of extracting 1032 leads in 647 patients with a clinical success in 97.6% of the patients and a major complication rate of 0.9%. They suggested that these good results are an impulse to expand the extraction of superfluous non-functional leads. Their major indication for lead extraction remains an infected pacing or defibrillation system, with local infection or skin erosion in 36.4% and systemic infection in 24% of the patients treated. Although there may be debate as to whether an initial conservative attempt at treating local pacemaker or defibrillator-related infections is justified, total removal of the pacing or defibrillation system is probably the most reliable way to cure device-related infections, and these results of lead extraction encourage timely lead extraction for this indication. 2 But the authors also mentioned that the over 25% share of superfluous leads extracted over the study period reflected both an increasing demand for extraction of these leads and an increasing extractor confidence. Other papers on lead extraction show the same inclination: in a recent paper Jones et al.3 described 975 leads extracted in 498 patients, 38% of the leads removed could be considered superfluous. They hinted that the risk of abandoning leads is greater than the complication rate of lead extraction in their study: even with a rate of complications from abandoned leads reported being as low as 5.5%, this was still higher than the complication rate from extraction in their study. (97.5% of leads completely extracted with major complications in 0.4% of the patients.) But does the skillfulness to perform lead extraction solely justify its application? Often, reports of complications of abandoned leads are invoked to support the indication for lead. Among the complications cited is the fear of occluding venous passage with an increasing number of leads implanted. Jones et al. referred to 16 out of 428 patients reported by Suga et al.4 in whom venous occlusion was detected at the time of a later implantation of a new lead. But it is dubious to consider venous obstruction a complication of superfluous leads, as total angiographic venous obstruction is already present in around 10% of uncomplicated primary pacemaker or defibrillator implants, even though only a minority of these patients experiences symptoms. Further, several studies have refuted the hypothesis of an increased risk of occlusion with multiple leads. 5 , 6 But most importantly, the risk of actually invoking venous occlusion by lead extraction is largely uncharted and no comprehensive follow-up studies have been done. We performed a clinical evaluation after laser lead extraction and found signs or symptoms of venous obstruction in five out of 52 previously asymptomatic patients. 7 Given the often asymptomatic course of this complication, the angiographic incidence of occlusion especially with powered sheaths could be significantly higher. Therefore, before risk of venous obstruction can be invoked as an indication for lead extraction, the risk imposed by the extraction procedure itself should be first properly explored. Another indication regularly cited for extracting superfluous leads is the risk of electrical interference, especially in defibrillator therapy. However, Wollmann et al.8 compared implantation of an additional shock lead versus extraction of the defective lead and implantation of a new one but found no higher incidence of complications, especially not concerning oversensing or inappropriate shocks. Also Glikson et al. in an observational study recently concluded that abandoning defective leads did not yield a clinical significant risk for future complications. 9 Besides, paying attention to and avoiding contact between retained and new leads should belong to the skills of anyone involved in device therapy. Some of the published complications of indwelling leads can be attributed to the outcome of unsuccessful extraction attempts. A number of the complications mentioned by Bohm et al. followed non-successful extraction attempts at which some leads were cut short and not properly secured inside the pocket. 10 This predisposed to lead migration and caused the most serious complications reported in this paper. Therefore, these data rather point to the risk of ill-fated lead extraction than to the risk of properly abandoning leads. Lead extraction adds substantially to the cost of the procedure if compared with just abandoning the non-functional leads. To adequately care for complications, extractions have to be performed in an operating room, with different extraction tools at hand, and as the authors state, the willingness to be very prepared to treat complications including the standby of a cardiosurgical team. The procedures are also preferably performed by an experienced team, which makes referral to another centre often necessary. It might be argued that all these precautions are not always necessary, but the authors pointed out that several leads implanted for less than a year already needed laser extraction and hence should be taken care of in a proper environment. In younger patients, extraction of superfluous leads is often advocated on the argument that these patients run a risk of accumulating multiple lead revisions over their lifetime, ultimately prohibiting implantation of new leads. But also for this population the advantage of extraction over abandoning superfluous leads remains speculative. Occlusion of the veins after lead extraction might be as prohibitive to insert new leads later on as the presence of multiple leads. This notwithstanding, as Kennergren et al. also pointed out, recently implanted leads have a good chance of removal by simple traction alone. The decision to remove these leads depends on the time they have been implanted, type of lead, and importantly on to the experience of the operator. If it is anticipated that one cannot remove leads by simple traction, it may be preferable to abandon them. One should be cautious to extend the excellent results of Kennergren et al. to the general practice of lead extraction. The authors warned that ‘their results extracting superfluous leads should not be used a recommendation to low volume centres to embark on extracting such leads without doing a serious individual risk–benefit analysis and being very well prepared to treat complications’. But less favourable outcomes of lead extraction even from experienced centres can also be found in the literature. Recently, the outcome of generator exchange in the setting of device recalls has demonstrated that perceived risk can turn out to be less than that of the proposed cure. This might also hold true for superfluous leads, and there should be caution to follow the suggestion by Kennergren et al. that the paradigm of abandoning redundant leads instead of removing them may have to be reconsidered should other studies confirm their results. Instead, what is first needed is a comprehensive study of the presumed risk of abandoning non-functional leads, and even if these should be present, it still has to be shown that on balance lead extraction will be beneficial for the patient. Conflict of interest: none declared.