The use of cardiovascular implantable electronic devices (CIEDs) has increased dramatically over the last few decades, with almost 1.2 to 1.4 million CIEDs implanted annually worldwide.1 In parallel with this, device- or lead-related complications and extractions have also risen significantly—especially in the aging population who tend to have more medical comorbidities. Although newer technological advancements allow the implantation of leadless pacemakers and subcutaneous implantable cardioverter-defibrillators (ICDs) in select populations, the majority of implanted devices are still transvenous.
Lead extraction via heart surgery, primarily used until the 1980s, is now reserved for certain scenarios such as failed percutaneous lead extraction, leads with very large vegetations in endocarditis, and when other cardiac surgery is needed, such as valve replacement. Early nonsurgical techniques introduced in the 1960s included simple mechanical traction and the use of weight and pulley systems to provide sustained traction.2 Telescoping mechanical sheaths made of stainless steel, polypropylene, or Teflon were introduced in the 1980s, resulting in superior transvenous extraction rates approaching 80%. The availability of locking stylets in the 1990s allowed for lead reinforcement, and powered sheaths using excimer laser system became available in the mid-1990s.
Transvenous lead extraction (TLE), as a part of overall lead management, has grown markedly since the 1990s, not only as a consequence of growth in CIED implants and increasing rates of infection and lead failure but also because of increased awareness of indications for lead management and the development of more advanced and safer extraction tools.3
Removing the pulse generator is generally uncomplicated, as is transvenous removal of recently implanted leads (<12 months). However, extraction of chronic leads is often challenging with inherent life-threatening complications owing to scar or fibrous adhesions as well as calcifications.4 The degree of endothelial fibrosis is related to the length of time the lead has been implanted and the patient’s vascular inflammatory reactivity. Fibrotic attachments are found not only at the lead tip, but can occur anywhere along the entire length of the lead—between the lead and the innominate vein, superior vena cava (SVC), tricuspid valve, or myocardium5 as depicted in Figure 64.1. Common sites are the innominate-SVC junction, the SVC-right atrial junction, the tricuspid valve, and the lead tip site. The earlier techniques of TLE relied on simple manual traction, frequently proved ineffective for chronically implanted leads, and carried a significant risk of myocardial avulsion, tamponade, and death. This limited the initial indications for TLE to life-threatening situations such as sepsis and uncontrolled infection. However, with the advancement in technology and availability of new extraction tools, TLE has become safer and more effective, with expanded indications.
FIGURE 64.1 Explanted leads to coronary sinus (left), right atrium (middle), and right ventricle (right) which demonstrate scar/fibrous tissue (yellow asterisks) attached to the lead tips and mid-portion of the leads.
Lead extraction is defined as a procedure where the removal of at least one pacing or defibrillator lead requiring the assistance of equipment not typically employed during lead implantation or at least one lead was implanted for greater than 1 year according to the Heart Rhythm Society (HRS) expert consensus statement on CIED lead management and extraction.1 The term “lead explant” is used when all leads are removed without tools or with implantation stylets and all the removed leads were implanted for less than 1 year. “Lead removal” indicates the removal of a lead using any technique, regardless of time since implantation.
INDICATIONS FOR LEAD EXTRACTION
Infection remains the most common indication for lead extraction, constituting almost half of all cases.6,7 There has been a slight downtrend in infectious indications in the last 10 years not because of a lower incidence of infections, but rather because of increasing indications for lead removal owing to other conditions such as lead dysfunction. The Lead Extraction in the CONtemporary setting (LExICon) study8 from 2010 reported 57% cases had infectious indications, decreasing to 53% in the European Lead Extraction ConTRolled registry (ELECTRa) study from 2017,7 and to 48% in the most recent Patient-Related Outcomes of Mechanical lead Extraction Techniques (PROMET) study9 published in early 2020. Lead dysfunction, abandoned functional leads, thrombosis/vascular access issues, and severe tricuspid regurgitation (TR) are the next most common indications for lead extraction. Chronic pain, recalled leads, malignant arrhythmias from abandoned leads, and the need for radiation therapy are other rare indications for lead extraction.
The current indications for lead removal are based on the updated HRS expert consensus statement from 2017,1 and the complete list is provided in Tables 64.1 and 64.2. The infectious indication for removal is based on mortality benefit and reduced morbidity associated with infected CIED removal as well as the inability to medically treat the contaminated devices. However, the decision-making process regarding lead extraction for noninfectious indications needs to be individualized. There are no randomized clinical trials to guide treatment in these situations. Hence, a careful assessment of the risks of extraction versus the potential clinical benefits related to that particular indication needs to be weighed on a case-by-case basis.
FACILITY CONSIDERATIONS
Lead extractions should optimally be performed in high-volume centers with experienced operators, given the risks associated with the procedure, especially for older leads and multiple leads in high-risk patient populations. The key requirement is that the facility provides the necessary equipment and personnel to perform lead extractions and manage complications safely.10 These extraction procedures are usually undertaken in operating rooms or hybrid laboratories, whereas removal of younger leads can often be safely performed in electrophysiology laboratories. A subanalysis of ELECTRa registry showed that TLEs are performed in the operating room in 53% of patients, hybrid rooms in 20% of patients, and catheterization laboratories in 27% of the patients.11 The ability to provide immediate surgical intervention in cases of major complications—such as an SVC tear or cardiac avulsion with tamponade—makes the operating room and the hybrid laboratory the best options to perform lead extractions in high-risk cases. The cardiac surgeon and a full support team—including cardiopulmonary perfusionist and equipment—must be available to provide emergent open-chest surgical repair within 5 to 10 minutes.12 Although studies have shown increased complication rates (including SVC tear and death) when both the cardiologist and cardiothoracic surgeon are performing the case compared to cardiologists alone, this actually reflects the high-risk profile and complexity of these cases which warranted the procedure being done in the operating room in the first place.11 Hence, in our institution, we adopt an integrative approach between the cardiac electrophysiologist and the cardiac surgeon, where both are scrubbed in for the cases, which are predominantly performed in the operating room or hybrid laboratory with cardiopulmonary bypass standby.12
TABLE 64.1 Recommendations for Lead Extraction (Infectious)
Class
Recommendations
I
If antibiotics are going to be prescribed, drawing at least two sets of blood cultures before starting antibiotic therapy is recommended for all patients with suspected cardiovascular implantable electronic device (CIED) infection to improve the precision and minimize the duration of antibiotic therapy.
I
Gram stain and culture of generator pocket tissue and the explanted lead(s) are recommended at the time of CIED removal to improve the precision and minimize the duration of antibiotic therapy.
I
Preprocedural transesophageal echocardiography (TEE) is recommended for patients with suspected systemic CIED infection to evaluate the absence or size, character, and potential embolic risk of identified vegetations.
I
Evaluation by physicians with specific expertise in CIED infection and lead extraction is recommended for patients with documentedCIED infection.
IIa
TEE can be useful for patients with CIED pocket infection with and without positive blood cultures to evaluate the absence or size, character, and potential embolic risk of identified vegetations.
IIa
Evaluation by physicians with specific expertise in CIED infection and lead extraction can be useful for patients with suspectedCIED infections.
IIb
Additional imaging may be considered to facilitate the diagnosis of CIED pocket or lead infection when it cannot be confirmed by other methods.
Preprocedural risk stratification of patients helps to identify and carefully select which procedures need to be undertaken in the operating or hybrid room with appropriate expertise to manage potential lethal complications. Several studies have identified high-risk features that are more commonly associated with periprocedural complications including death. They include age (>68 years), female gender, lower body mass index (<25 kg/m2), anemia (hemoglobin <11.5 g/dL), number of prior CIED procedures, low-volume centers, New York Heart Association (NYHA) Class III to IV symptoms, chronic kidney disease, long lead dwell time (>10 years), and systemic infectious indication.7,11,13,14 Among these, advanced patient age, low-volume centers, NYHA Class III to IV symptoms, and systemic infection were directly related to increased all-cause mortality.7,11 A chest radiography showing multiple device leads (three active and two abandoned) is shown in Figure 64.2, which is one of the high-risk features associated with increased risk of periprocedural complications. Recently, Jachec et al14 developed a calculator to risk stratify the patients undergoing TLE to predict the probability of major complications (Table 64.3).
TABLE 64.2 Recommendations for Lead Extraction (Noninfectious)
Class
Recommendations
Thrombosis/Vascular Issues
I
Lead removal is recommended for patients with clinically significant thromboembolic events attributable to thrombus on a lead or a lead fragment that cannot be treated by other means.
I
Lead removal is recommended for patients with superior vena cava (SVC) stenosis or occlusion that prevents implantation of a necessary lead.
I
Lead removal is recommended for patients with planned stent deployment in a vein already containing a transvenous lead, to avoid entrapment of the lead.
I
Lead removal as part of a comprehensive plan for maintaining patency is recommended for patients with SVC stenosis or occlusion with limiting symptoms.
IIa
Lead removal can be useful for patients with ipsilateral venous occlusion preventing access to the venous circulation for required placement of an additional lead.
Chronic Pain
IIa
Device and/or lead removal can be useful for patients with severe chronic pain at the device or lead insertion site or believed to be secondary to the device, which causes significant patient discomfort, is not manageable by medical or surgical techniques, and for which there is no acceptable alternative.
Other
I
Lead removal is recommended for patients with life-threatening arrhythmias secondary to retained leads.
IIa
Lead removal can be useful for patients with a cardiovascular implantable electronic device (CIED) location that interferes with the treatment of malignancy.
IIa
Lead removal can be useful for patients if a CIED implantation would require more than four leads on one side or more than five leads through the SVC.
IIa
Lead removal can be useful for patients with an abandoned lead that interferes with the operation of a CIED system.
IIb
Lead removal may be considered for patients with leads that, because of their design or their failure, pose a potential future threat to the patient if left in place.
IIb
Lead removal may be considered for patients to facilitate access to magnetic resonance imaging (MRI).
IIb
Lead removal may be considered in the setting of normally functioning nonrecalled pacing or defibrillation leads for selected patients after a shared decision-making process.
