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 Table of Contents  
REVIEW ARTICLE
Year : 2018  |  Volume : 3  |  Issue : 1  |  Page : 25-29

Transvenous lead extraction: Barriers to care


Cardiovascular Division, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, USA

Date of Web Publication23-Jul-2018

Correspondence Address:
Dr. Laurence M Epstein
Arrhythmia Service, Brigham and Women's Hospital, Harvard Medical School, 75 Francis Street, Boston, MA 02115
USA
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Source of Support: None, Conflict of Interest: None


DOI: 10.4103/IJHR.IJHR_7_16

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  Abstract 

The need for transvenous lead extraction (TVL) is increasing. Unfortunately, many patients with indications for extraction go without appropriate care. There are multiple barriers to patients receiving TVL. These include a knowledge deficit, a lack of adequate training, a lack of appropriate tools, and a lack of resources. In this paper, we will review these barriers and offer some potential solutions. Hopefully, in the near future, all patients that require TVL will be appropriately referred and the resources and training will allow safe and effective treatment.

Keywords: Cardiac implantable electronic devices, device infection, laser, lead extraction, lead fracture


How to cite this article:
Epstein LM. Transvenous lead extraction: Barriers to care. Int J Heart Rhythm 2018;3:25-9

How to cite this URL:
Epstein LM. Transvenous lead extraction: Barriers to care. Int J Heart Rhythm [serial online] 2018 [cited 2018 Dec 12];3:25-9. Available from: http://www.ijhronline.org/text.asp?2018/3/1/25/237370


  Introduction Top


The benefit of cardiac implantable electronic devices (CIEDs) has been well established from life-saving cardiac pacing and defibrillation to quality of life improving resynchronization therapy. This had led to a dramatic rise in implants worldwide. Unfortunately, these devices are not without problems. The “weak link” in all CIEDs is the leads. These complex cables must bear the stress of each cardiac cycle along with flexion due to body movement.[1] In addition, in recent years, we have been seeing an increasing number of lead-related recalls and advisories.[2]

Finally, when a device-related infection occurs, all hardware, including the leads, must be removed.[3] This is true for pocket infections as well as systemic infections. Not removing all the hardware is associated with a significant increase in mortality. Despite clear indications, it is estimated that only one-quarter of patients who would benefit from transvenous lead extraction (TVL) are referred for the procedure. This number is surely smaller worldwide. Why is this the case? What are the barriers to patients receiving appropriate care?


  Barriers to Care Top


Unfortunately, there are many reasons patients do not receive appropriate care. These include a knowledge deficit, a lack of adequate training, a lack of appropriate tools, and a lack of resources. We will review each of these and discuss potential remedies.


  Knowledge Deficit Top


This barrier to care includes a lack of understanding of the indications for extraction, including the consequences of not following the recommendation, a misconception of the risks associated with TVL, and a lack of understanding of the consequences of lead abandonment.

A lack of knowledge of the Indications for transvenous lead extraction

The 2009 h/ACC/AHA consensus document on TVL clearly outlines the indications for lead extraction which is divided into classes.[3]

  • Class I: Conditions for which there is evidence and/or general agreement that a given procedure or treatment is useful and effective
  • Class II: Conditions for which there is conflicting evidence and/or a divergence of opinion about the usefulness/efficacy of a procedure or treatment


    • IIa: Weight of evidence/opinion is in favor of usefulness/efficacy
    • IIb: Usefulness/efficacy is less well established by evidence/opinion


  • Class III: Conditions for which there is evidence and/or general agreement that the procedure/treatment is not useful or effective and in some cases may be harmful.


Class I indication, including systemic and pocket infections, should undergo TVL, and Class IIa indication patients should be offered TVL. In a recent study, we surveyed cardiologists, electrophysiologists, and device company representatives in the United States to determine their knowledge base concerning TVL. This included indications for extraction. Almost 50% of cardiologists and device company representatives would not recommend TVL for patients with clear pocket infections, a Class I indication. These results were not surprising. All too often we see patients treated with multiple courses of antibiotics and multiple “debridement” or “salvage” procedures before they are ultimately referred for extraction. Allowing a pocket infection to progress to a systemic infection, due to ineffective treatment, dramatically increases mortality.

We and others found in two large series of patients undergoing TVL that systemic device-related infection was associated with a near 25% 1-year mortality. This was despite successful extraction and no procedure-related deaths.[4],[5]

Given these data, why are more patients not referred. Many physicians are unaware that device-related infections cannot be cured without complete removal of all hardware. They often think antibiotics alone, or antibiotics plus debridement is a reasonable option. The thought process is “if this approach fails, we can always send them for extraction.” Clearly, they are unaware of the risks associated with these types of delays. Education is the important remedy for this deficiency in knowledge.

A misconception about the risks of lead extraction

I believe fear may be the most important reason why more patients are not offered TVL. Although, with current tools, TLV is both safe and effective,[6],[7],[8] many physicians think the risk if far higher and will “do anything else” before sending a patient for extraction. Historically, lead extraction could only be performed with direct traction on the lead or through open heart surgery. Both were associated with significant morbidity and mortality. Therefore, for many older physicians, this has resulted in a “lasting” impression of lead extraction that is hard to change. Dr. Charlie Byrd is credited with developing the “modern” approach to TVL, using telescoping sheaths and counter traction.[9] Building upon this has been the development of locking stylets and “powered” sheaths both mechanical and laser. A previous study has now demonstrated an over 95% success rate with a <2% major complication rate and a <0.3% mortality.[10] This is far lower than many completely elective procedures such as ablation for the treatment of atrial fibrillation. The worldwide registry reported a 4.5% complication rate and a 0.12% mortality.[11]

We need to convert the thinking that sending a patient for extraction is potentially sending a patient to death to not sending an infected CIED patient for extraction dramatically increases mortality and is a life-threatening condition.

A lack of understanding of the consequences of lead abandonment

I have heard on many occasions “why would you ever extract a noninfected lead?” Proponents of this approach believe that TVL carries an unacceptable risk and lead abandonment carries minimal or no risk. If these two assumptions were true, I would agree, but I do not think they are. As reviewed above, TVL carries a lower risk than many of the invasive elective procedures that are routinely performed. In addition, lead abandonment has been shown to carry significant risk. These include an increased risk of infection, venous occlusion, lead migration, lead interaction, more difficult extraction in the future, and prevention of future magnetic resonance imaging (MRI) scans.

Multiple studies have demonstrated that having 3 or more leads increases the risk of infection.[12],[13] This may be due to the increased “bulk” in the pocket and the fact that these patients often undergo multiple procedures. When an infection occurs, as was discussed above, it is mandatory to remove all hardware, including the leads. If there are older, abandoned leads present, this dramatically increases the difficulty and risk of TVL. If leads were removed when they failed or were no longer needed, many extractions procedures would be fare simpler and safer.

Venous occlusion is rare outside of trauma, neoplasm, or the presence of pacing leads. Approximately 30% of patients with any CIED have a venous occlusion. This clearly increases with the number of leads.[14],[15],[16] While many occlusions are asymptomatic, others lead to arm swelling or even superior vena cava (SVC) syndrome. In the HRS consensus document, avoiding placing 5 leads in the SVC is a Class II indication for extraction.[3] This is a real issue. We and others have performed extraction procedures and stenting for patients with SVC syndrome, many who have multiple leads.[17],[18],[19],[20],[21] In addition, patients may require new leads for a variety of reasons (lead failure, upgrade of a PCM to an ICD, and resynchronization). If the implant vein is occluded, many implanters choose to use the contralateral side for an entirely new implant or to place a new lead and tunnel it to the initial site. I do not believe that this is in the best interest of most patients. Venous access is a precious resource and should be preserved. The convenience of the physician should not be the reason to use all of a patient's available superior venous access. In such cases, venoplasty [22] or extraction with re-implantation [14] are far superior options.

While rare, lead migration and interaction can be significant problem.[23],[24],[25],[26],[27],[28],[29],[30],[31],[32],[33] Leads that are abandoned and not secured in the pocket can migrate into the vasculature, the heart, and the pulmonary artery. They can cause arrhythmias, including ventricular tachycardia, and be more difficult to remove in the case of infection.

There is a growing concern that cable extrusion of the advisory St. Jude Riata® lead, which increases overtime, will make this rare situation much more common.[34],[35],[36],[37],[38],[39],[40] The ethylene tetrafluoroethylene-coated cables can erode through the lead insulation and actually become free in the heart. Cases have also been reported of very large thrombi forming on these leads/cables. Abandoned leads can interfere with other leads in the heart. This can cause lead “noise” resulting in pacing inhibition and/or inappropriate shocks. Abandoned leads can also damage other leads rendering them nonfunctional.

As stated previously, “it is never easier to remove a lead than it is today.” It has been demonstrated that for every 3 additional years it is twice as hard to remove an abandoned lead. This is particularly problematic in cases of device-related infection as there is no choice and all the hardware must be removed, regardless of the age of the leads.

Finally, the use and need for MRI imaging is continuing to grow. Within a few years, all CIEDs will be MRI compatible (there are many such pacemakers and ICDs already). For a device patient to be safe in an MRI scan, it is often a combination of device and leads. While some patients may have MRI “safe” leads, where all that would be required would be a generator change, others do not. In these patients, extraction with re-implantation may be the only option. There are studies that demonstrate that some patients with “modern” pacemakers and ICDs may be safe to scan. However, if a patient has an abandon lead is an absolute, it is an absolute contraindication to MRI scanning.


  A Reluctance to Refer Top


Unfortunately, some physicians, who do not perform TVL, do not want to refer their patients. They want to care for them themselves even if it is not the optimal care. This pattern of practice is regrettable. Hopefully, guidelines and governmental/payer oversite can have an impact in this arena.


  Structural/resource Barriers Top


A lack of operating room space and cardiothoracic surgical backup

While rare, TVL does carry the risk of significant, life-threatening complications. Of these, a tear of the SVC is most lethal. Due to this risk, it is required that TVL extraction procedures be done in a setting where emergent, definitive rescue can take place, as described in the HRS consensus document.[3] This includes a room where cardiac bypass can be performed equipped with high-quality fluoroscopy. In addition, a complete team must be immediately available including a cardiac surgeon, perfusionist, scrub team, cardiac anesthesiologist, and echocardiographer. In addition to equipment and personnel, planning and training is required.

In the event of an emergent situation, it is a must that the entire team knows what to do. Unfortunately, at many hospitals, arranging for this type of backup and having time in the operating room can be difficult. This is particularly true in developing countries where resources may be scares and competing needs for these resources is great. Education and collaboration are critical to success. This often takes a lead extraction “champion,” someone dedicated to the needs of these patients who is willing to face the challenges required to develop a successful program.

Lack of access to tools and training

Finally, in many countries, there is a lack of access to the tools and training required to develop a successful lead management program. This leaves patients untreated, subjected to open heart surgery or desperate attempts at lead removal by those not experienced and without appropriate tools. Tools for performing lead extraction have evolved over the years. One of the most important tools is the locking stylet, for example, the Lead Locking Device® (Spectranetics, Colorado Springs, CO, USA). These devices dramatically increase the tensile strength of the lead increasing the chance of removing the lead in one piece. It also allows the lead to remain a “rail” so that extraction sheaths can be used to break up scar tissue, while safely staying within the intravascular space. Extraction sheaths have also evolved over the years, beyond the early polypropylene, steel, and Teflon® mechanical sheaths. The “counter traction” technique developed by Dr. Charlie Byrd involves passing the sheath over the lead to free it from scar tissue [10] and then at the end of the lead holding the sheath firm while placing tension on the lead, thereby focusing the forces at the lead tip. Beyond these simple sheaths, “powered” sheaths have been developed. These include mechanical rotating sheaths such as the Evolution® (Cook Vascular, Pennsylvania, USA) and the Tightrail® (Spectranetics, Colorado Springs, CO, USA). A more powerful “powered” sheath is the Excimer Laser (Spectranetics, Colorado Springs, CO, USA). Excellent results with the laser sheath have been demonstrated for over 20 years in multiple worldwide studies.[8],[41],[42],[43] The powered sheaths allow for a faster, more controlled extraction, with a higher success rate and fewer lead disruptions.

While I attempt to extract leads from the implant vein in most cases (usually a superior approach), there are times, such as when leads are free in the heart, this approach is impossible. In those cases, a femoral approach may be required. Other times, the leads may disrupt during superior extraction or progress is difficult. Again, switching to a femoral approach may be required. Having a full array of femoral tools, including large sheaths and a variety of snares, is required. Some of these tools may be found in the interventional radiology department.

Unfortunately, in many countries, these tools may not be available due to a lack of regulatory approval and/or cost. To overcome this barrier, the extraction “champion” must educate the key decision-makers as to the need. In addition, partnering with industry is crucial to overcoming regulatory hurdles, training requirements, and costs. A single physician or center can only care for a limited number of patients. The number of patients receiving appropriate care may be exponentially increased by a commitment to training others and helping them develop programs. Through these efforts, the great unmet needs can be met.


  Conclusion Top


The need for TVL is increasing. New tools and techniques have dramatically increased the safety and efficacy of this procedure. While barriers to care do exist, they are not insurmountable. A dedicated physician “champion” can lead the effort to develop a successful program, through education, partnering with industry, and perseverance.

Financial support and sponsorship

Nil.

Conflicts of interest

The authors declare that they have no conflicts of interest.

 
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  In this article
Abstract
Introduction
Barriers to Care
Knowledge Deficit
A Reluctance to ...
Structural/resou...
Conclusion
References

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