By Charles Love
Cardiac implantable electronic devices have become a major part of the management strategy of not only patients with documented bradycardia and tachycardia, but also in those with impaired left ventricular function (for primary sudden cardiac death prevention and treatment of congestive heart failure). Device lead failures, lead related endocarditis, device pocket infections and other issues have created patient management challenges since the first permanent pacemaker was placed in 1958. As the number of device implants increased over the past 50 years, the number of complications increased in parallel. Though infection has been the most compelling reason for extraction of intravascular and endocardial lead systems, some lead issues (such as the Telectronics Accufix J-leads and the more recent Medtronic Fidelis leads) have resulted in significant “spikes” in lead extraction volumes.
Initially, lead extraction was practiced by a handful of experts. However, as the indications for extraction evolved and the need for management of lead and pocket related complications grew, extraction became more widely practiced. Unfortunately, and even recently, many physicians were trained in a “see one, do one” manner. Data have been available for some time confirming that this type of training is not appropriate for such a complex and potentially difficult procedure.
In 1997, the first policy conference was held to discuss lead extraction, with a policy statement published in 2000 by NASPE. This served as a source document for the past nine years. Last year, at the 2008 annual scientific sessions of the Heart Rhythm Society (HRS), another conference was held to revisit the issues involved with lead management, and an updated policy statement was published this year in HeartRhythm. This document updates and highlights the issues related to lead management, and specifically regarding lead extraction.
While “lead removal” is the removal of any lead by any technique, “lead extraction” is defined as removal of a lead that has been implanted for more than one year, or a lead regardless of duration of implant requiring the assistance of specialised equipment that is not included as part of the typical implant package, and/or removal of a lead from a route other than via the implant vein. It should be noted that a successful extraction usually involves removal of the entire targeted lead (or leads), but one can achieve the intended clinical result while retaining a small portion of the lead (such as the tip). This would still allow for resolution of a pocket infection, opening a new channel through an occluded vessel, or allowing resolution of endocarditis.
Lead extraction can result in a number of complications that can be life threatening or result in death. Under most circumstances, the risk of this type of complication should be less than 1%. However, the risk will vary based on individual and institutional factors. For this reason, the new policy statement places an emphasis on physician and staff training, as well as preparedness for the inevitable complication requiring immediate response. Events may include myocardial and venous tears, pericardial tamponade, haemothorax, AV fistula and pulmonary embolism. In order to achieve a high rate of procedural success and manage complications, a team approach is mandatory. Starting with a trained operator who has performed a minimum of 40 lead extractions as a trainee (and maintaining a volume of at least 20 extractions per year), having a cardiothoracic surgeon (on site and immediately available) who is familiar with the types of injuries associated with extraction, to a team of nurses and technicians in the lab/OR, which is familiar with the techniques and tools used for extraction. As with any procedure, simply performing a specific number of procedures does not guarantee proficiency. Importantly, the entire group must know what to do and when to do it for both routine extractions as well as those that result in a complication. The use of “fire drills” to assure team preparedness for complications is recommended and is an excellent way to “fine tune” the team’s response, as saving minutes will save lives. Physicians are encouraged to offer their personal success, failure and complication rates as a part of the informed consent process, rather than using a number published in the literature.
Those of us who have performed thousands of lead extractions have come to recognise that there is no single extraction tool that will work in all situations. The operator and team need to have and be experienced with multiple types of extraction sheaths, snares, locking stylets and other tools to have the highest success rates with minimal complications.
Though the indications for lead extraction have not changed dramatically in the new document, they have undergone clarification and enhanced categorisation. There is an increased emphasis on the need to remove all hardware from the pocket and vasculature when pocket infection or colonisation is present. The indications remain firm for lead removal when endocarditis is present or recurrent bacteraemia when no other source of seeding can be found.
An increasingly common reason for extraction is venous occlusion at the time of device upgrade or need for new lead implant. Extraction can provide a new channel through the vessel so that the contralateral side can be preserved, as bilateral occlusion could result in superior vena cava syndrome. One of the more controversial indications in the document is the need to remove a device should an MRI scan be necessary and no other imaging modality will suffice. There are growing data in the literature that with proper programming and monitoring, MRI may be safe for many patients without removing the device and leads as long as the scan is of the head or is at or below the level of the lumbar spine. Currently, device labeling mandated by the FDA states that MRI is contraindicated in device patients, thus the inclusion of need for an MRI as an indication for extraction.
Lead extraction is a necessary and useful procedure to help in CIED management. When practiced by well trained physicians with well trained support, at institutions with the appropriate resources, it is a very safe and effective technique. As new tools become available, it is anticipated that the very high success rates will get even higher, and that perhaps safety will increase.
Charles Love is director of Cardiac Rhythm Device Services and professor of medicine at The Ohio State University. He also serves as the president of the International Board of Heart Rhythm Examiners.