During recent years there has been a significant increase in pacemaker implantation. Consequently, the number of possible complications and the need for pacemaker lead extraction has grown as well. The most common indication for pacemaker lead extraction is localized or systemic infection. Since lead extraction is among the most complex and dangerous cardiologic procedures, new techniques and tools are being developed on a yearly basis that significantly facilitate extraction and reduce the risk of possible, often very severe, complications. Considering the above, it is necessary to organize enough appropriate centers with specialized multidisciplinary teams trained for the performance of these procedures. Since early 2013, a pacemaker lead extraction program was started at the Department for Arrhythmia and Electrical Stimulation at the University Hospital Centre Rijeka. Over a period of two and a half years, a total of 27 procedures have been performed and 51 pacemaker leads were extracted, of which two were defibrillator leads. The main cause of lead extraction was localized infection/pocket decubitus, while the incidence of systemic infection was much lower. Extraction techniques used were predominantly traction and locking stylet extractions. The most significant complication was the development of symptomatic pericardial effusion. There were no fatal outcomes.
Pacemakers have an important role in heart disease treatment, and we are witnessing a significant increase in the number of implanted devices. There are more than 4.3 million patients globally that have been implanted with one of several types of pacemakers, and their number grows daily. These devices include those used to treat bradycardia, implantable cardioverter defibrillators, or heart resynchronization devices. Due to the significant increase in implantations and the fact that the patients in question are often older and with an increasing number of comorbidities, the number of possible complications and consequently the number of necessary extractions is growing as well. The most common indications for lead extraction are localized or systemic infections (pocket infection, valve vegetation, sepsis), fractures, i.e. lead malfunctions, system upgrades, a retained lead or its part, and vein obstruction.
Removing a pacemaker system consists of two phases: removing the pulse generator, which is followed by the removal of one or more leads, including all additional parts of the system such as adapters, sutures, etc. Removing the generator is a fairly simple procedure, but when a pocket infection is present a broad resection must be made as well as debridement of the infected tissue. Transvenous lead extraction of recently implanted leads (less than 3 months since implantation – this is called explantation) can be achieved using the method of direct traction, but older leads that have undergone fibrous encapsulation (more than a year since implantation – this is called extraction). Adhesions are present at the point of contact between the lead and the myocardium but also at other points of contact in the venous system, valve and endocardial areas, which means that the traction procedure is not sufficient and, if attempted, can lead to disintegration of the lead which further complicates the procedure. Due to the above, new methods and tools for safe transvenous removal have been developing during the last twenty years.
The main principle in lead explantation/extraction is that the risk from the procedure must be lower than the possible complications of retaining the implant. Today, most procedures are performed using the percutaneous transvenous method. Surgical procedures are necessary in rare cases, such as unsuccessful attempts at using the percutaneous method, when surgical treatment is needed to treat other diseases (e.g. replacing the valve), or in cases of significant vegetation on the valve which makes the percutaneous method inappropriate due to possible embolic incidents. Several techniques of percutaneous transvenous extraction have been developed.
The traction procedure is the simplest method of lead removal that has been applied over the last forty years. A standard stylet is inserted into the lead which is then extracted through gradual application of pulling force. This method is generally confined to explants; when extracting older fibrously encapsulated leads there is a risk of disintegration. Possible complications of this procedure include myocardial invagination or rupture, arrhythmia, and severe tricuspid regurgitation due to valve avulsion.
In this technique, a special traction stylet is introduced into the lumen of the lead, reducing risk of lead disintegration. The proximal end of the lead is removed, after which the stylet is introduced into any part of the lumen. It is preferable for the stylet to be as close to the distal end as possible, because otherwise unwanted disintegration of the lead may occur due to elongation. Possible complications are the same as in the traction method without a locking stylet.
A sheath is basically a tube (made of propylene, metal, or Teflon) which is gradually passed over the lead. This creates mechanical force that acts on the existing adhesive tissue and releases the lead. The procedure also requires a locking stylet with is used to oppose the force of the sheath. The sheath is brought to the tip of the lead until it touches the myocardium, which prevents invagination during lead traction (using a locking stylet).
Electrosurgical sheaths are a special type of sheath with two electrodes at their tip that use radiofrequency energy to dissect the fibrous tissue.
This technique uses a laser sheath constructed from a thin layer of optical fibers placed between two polymer layers. A circular laser beam is delivered at the tip of the sheath that removes surrounding fibrous tissue. The extraction procedure is the same as with other sheaths.
Lead extraction is a complex procedure that can cause many unwanted complications. We can divide the complications into two main groups: less serious and serious. Serious complications include death, avulsion or tearing of the myocardium with consequent tamponade, avulsion or tearing of the large veins, pulmonary embolism that requires surgical intervention, etc. Less serious complications that can occur are pericardial effusion which does not require pericardiocentesis or surgical intervention, hematothorax that does not require a thoracic drainage, swelling of upper extremities, or thrombosis of the vein through which the lead was introduced, air embolism, pneumothorax, etc. (
Lead extraction is considered an invasive procedure that requires adequate training and experience to ensure quality care and safety for the patient. As with any invasive procedure, there is a learning curve in achieving the necessary competence. Current guidelines of US and European arrythmological societies include minimal conditions regarding the skill of the operator and equipment in the center in which the procedures are to be conducted. (
The operator must be a fully trained implanter of cardiovascular implantable electronic devices (CIED) with a large annual implantation procedure count.
They must perform at least 40 lead extractions in 30 different procedures as the primary operator under the supervision of a qualified operator. The extractions must include at least 10 cases of extraction of at least two leads, 10 procedures of defibrillator lead extraction, and 10 procedures where the leads were implanted more than 6 years ago.
After completion of the training, the operator must perform at least 15 procedures annually as the primary operator for a total of at least 20 extracted leads.
The extraction center must be a qualified high-frequency center for the implantation of all types of cardiovascular electrical devices.
At least 15 extractions must be performed annually in the center, with a total of at least 20 extracted leads.
Extraction team members must be familiar with the procedure, extraction tools, possible complications, and emergency procedures.
The extraction center must have a surgical team available that is trained to treat urgent, life threatening complications that require surgical intervention, as well as an extracorporeal circulation device. The most dangerous complication is laceration of the superior vena cava, which requires surgical intervention with thoracotomy within 10 minutes.
An anesthesiological support team trained for administering anesthesia in cardiac surgeries must be available for emergency cases.
The procedures must be performed in an electrophysiological laboratory/operating hall with a quality X-Ray machine. Various tools for lead extraction must be available, as well as a pericardiocentesis kit and a temporary electrostimulation device as well as an echocardiography device.
Two recent studies conducted in the US and Europe showed that many centers performing lead extraction procedures still do not fulfill the abovementioned conditions, but the Task Force of Lead Extraction stands behind its guidelines. (
The lead extraction program at the Department for Arrhythmia and Electrical Stimulation at the University Hospital Centre Rijeka was started in early 2013. In the 2.5 years since then (up to June 30, 2015), 27 procedures were performed and 51 leads were extracted. Leads were extracted in 22 procedures while the remaining five were explantation procedures (
2013 | 2014 | 2015* | Total | |
---|---|---|---|---|
Number od CIED implantation |
402 |
455 |
263 |
1120 |
Number of complex devices implantation (ICD, CRT) |
49 |
61 |
52 |
162 |
Number of extractions |
5 |
10 |
7 |
22 |
Number of extracted leads | 9 | 19 | 15 | 43 |
*Data untill June 30, 2015
N (%) | |
---|---|
Average age (years) |
76.5 |
Male gender |
16 (72%) |
Prevalence of extraction |
22/1120 (2%) |
Number of successfully extracted leads |
42/43 (98%) |
Complications |
1 (4.5%) |
Mortality |
0 |
Type of the extracted leads |
|
• Ventricular |
21 (49%) |
• Atrial |
20 (46%) |
• Defibrillator | 2 (5%) |
Average time from implantation to extraction was 4.5 years, whereas the average time to explantation was 2 months. The main reason for lead extraction was local infection and/or pocket decubitus, with systemic infection being very rare. Systemic infections were caused by methicillin-resistant Staphylococcus aureus (MRSA), and one patient suffered from tricuspid valve endocarditis. In two patients the pacemaker system was removed to perform cancer radiotherapy, and it was removed in another two patients due to lead fractures (
Etiology of lead explantation/extraction.
Local infection and decubitus of the pocket with pacemaker protrusion.
In 90% of patients standard pacemaker leads were extracted, but there were two cases of defibrillator lead extractions. Of a total of 43 leads, 42 were completely removed while one atrial lead snapped and a piece was retained in the heart (98% success). The only significant complication was a symptomatic pericardial effusion 1 cm thick in one female patient, which did not require emergency pericardiocentesis and was treated conservatively. There have been no mortalities so far.
Lead extraction prevalence in our center was approximately 2%, which is in line with global trends that are between 1.5 and 6%. (
Extraction procedures take place in a multipurpose cath lab equipped for all types of invasive cardiologic procedures. The procedure takes place under heavy sedation and analgesia with the option to convert to general anesthesia and with continuous vital signs monitoring. During extraction, in the cath lab is present an anesthetic machine, an ultrasound device, a pericardiocentesis kit and a temporary electrostimulation device, and, depending on preoperative appraisal, an extracorporeal circulation device. In addition to standard preparations as with pacemaker implantation, the patient is also prepared for emergency pericardiocentesis and thoracotomy. A cardiac surgeon is on call during the procedure, in case of tamponade or large vein laceration.
We used traction and counter-pressure methods to extract the leads with the use of a locking stylet, fixating sutures, and single and double sheaths (
Extraction with combined use of a "locking" stylet and a fixation suture.
Lead removal using a sheat which mechanically disrupts the fibrotic adhesions.
Example of an extracted lead with clearly visible fibrotic adhesions.
Example of a postoperative wound after the extraction of a defibrillator and three leads.
The basic difficulty we faced in developing the lead extraction program is that health insurance does not recognize the complexity of these procedures. Inadequate financing limits the acquisition of more expensive additional equipment that would facilitate and improve performance of the procedures, such as mechanical sheaths, femoral snares, etc.
In Croatia it is also necessary to form specialized lead extraction centers to which patients would be referred to in order to increase the number of procedures per center and their quality. If we take into account the 2800 CIED devices implanted in Croatia annually, the annual need for lead extraction would be between 40 and 165 procedures, which indicates the need for the formation of 1-2 specialized lead extraction centers. Currently, lead extraction is a high-risk, unprofitable procedure performed sporadically in individual centers based on the enthusiasm of individual operators.
Lead extraction procedures are among the most complex and dangerous cardiologic procedures and the need for them is increasing. To properly perform these procedures, adequate centers must be organized with multidisciplinary trained teams equipped with all the necessary tools, apparatuses, and adequate procedure capacity.