Creation of a Conduit

The rationale for creating a conduit is applicable to component failures. Consider a patient with a dual-chamber pacemaker and an atrial lead conductor coil fracture. This patient has a normal ventricular lead, an occlusion of the brachiocephalic vein, and the need to implant a new atrial lead. Although venoplasty through the total occlusion is possible, a more reasonable approach to maintaining access through the same vein entry site is to extract the failed atrial lead and to insert the new lead through the extraction conduit, or to remove both existing leads and start over with new leads. This same logic would apply to other situations, such as an upgrade requiring the addition of a new lead. For example, a patient with a dual-chamber ICD requires a cardiac vein implant for biventricular pacing. The alternatives are doing nothing, implanting the new lead through a contralateral vein or a transfemoral vein, or using a cardiac surgical approach. Venoplasty is also reasonable if the existing leads are all functional.

Sometimes, when there is severe stenosis with or without symptoms from the obstruction of flow, physicians have initiated balloon venoplasty and stenting without extraction of the leads. This is particularly difficult if either infection or reocclusion occurs, because extraction now becomes impossible without extensive open-heart surgery (Fig. 26-7). A more appropriate approach includes extraction, venoplasty, stenting, and reimplantation through the stent, as reported by Chan et al.⁷ in a subclavian occlusion that progressed to an SVC occlusion.

Figure 26-7 Severe stenosis.

Leads are stented to the superior vena cava (SVC), making extraction in case of infection impossible. The patient required surgery and an SVC graft.

Implantation through a contralateral vein seems logical, especially if it is the implanter’s only skill-level option. The simplest alternative is to abandon the two original leads on the ipsilateral side and implant the new leads on the contralateral side. In the example of a conductor coil fracture, the patient has the risk of having two functioning and two nonactive leads in the heart and the risk of instrumentation of the superior veins on the opposite side. In the example of adding a left ventricular lead for biventricular stimulation, the patient has the risk of having three functioning leads and two nonactive leads in the heart and the risk of instrumentation of the superior veins on the opposite side. These risks are weighed against the risk of extracting the one atrial lead. The resultant risk of having a complication is the sum of the individual risk factors.

For these two examples, another approach would be to implant the new atrial lead or biventricular lead on the contralateral side and tunnel it across to the pulse generator and ventricular lead. In addition to the risk of instrumentation of the superior veins and tunneling, the patient with conductor coil fracture will have two functioning leads and one nonactive lead in the heart, and the patient with the biventricular lead will have three functioning leads in the heart.

Total bilateral occlusion of the superior veins further complicates the problem. The transfemoral approach is then the only approach available to the nonsurgeon implanter. The surgical implanter has the options of a transatrial or epicardial approach. The risks associated with these choices make the decision to extract the atrial lead easier. However, without extraction skills, the medical and surgical implanter may choose these alternatives.

The risk/benefit ratio is crucial to the rationale for extracting these leads. For example, the life-threatening risk associated with infection in effect forces an implanter to extract the lead and abandon the pocket. The risk of not creating a conduit to insert new leads is a potential risk for a future complication related to bilateral implants, nonactive leads, multiple implanted leads, and tunneling. This risk is obviously less than the life-threatening risk of infection. In the situation of lead failure, the alternatives presented provide an acceptable short-term solution and can be performed by implanters without lead extraction skills. Potential risks are not as compelling a reason for action as the immediate risks associated with lead extraction. However, physicians with experience in lead extraction may not be comfortable with abandoning two leads, creating two inactive leads, and leaving a total of four or five leads implanted. Tunneling of a lead from the opposite side, crossing over the sternum, is a potential source of infection and increased risk of lead fracture. Again, the risk of not extracting must be compared with the risk of extracting to help resolve these issues. To limit the risk of subclavian vein or SVC occlusion, it is considered reasonable to extract nonfunctional leads if a planned CIED implantation would require more than four leads on one side or more than five leads through the SVC.

Informed Consent

Written informed consent should be discussed with the patient, preferably in the presence of a family member. The patient and family must be made aware that lead extraction is a potentially life-threatening procedure, and this must be placed into local context by informing the patient about the hospital’s extraction volume and outcomes as well as the operator’s personal level of experience and outcomes. It is particularly important to discuss all alternatives when considering extraction versus abandonment during an upgrade procedure.

Tissue Closure

Healing by primary intention is the closing of an open wound by reapproximating tissue (muscle, subcutaneous tissue, and skin) using suture material. Suture holds the tissue in place until the tensile strength of the bonding fibrous tissue is sufficient to keep the tissue together. All initial and reimplanted pockets are closed in a conventional manner, reapproximating the tissue with suture material, and allowed to heal by primary intention. Chronic pockets are debrided of all exuberant inflammatory material before closure.

These pockets are debrided and closed using a closed-drainage system (Jackson-Pratt) placed in the debrided pocket, if necessary, applying suction to prevent the development of effusions or clot, and keeping normal tissue contiguous with normal tissue. A large defect resulting from loss of tissue during debridement may be challenging to close. In extreme cases, a major defect requires an experienced surgeon or a plastic surgeon, especially if a flap is needed. Alternatively, the pocket may be allowed to heal by secondary intention.

Another philosophy holds that pockets with debridement defects and infected pockets should be left open. Once the device (foreign body) is removed, the infection will heal, so allow it to heal by secondary intention. This rationale shortens the procedure and is an accepted method of healing. Infection is not an issue, and it avoids the need for acquiring surgical debridement and closure skills. Concerns such as morbidity, extensive healing time, long-term antibiotic therapy, constant professional care of the wound, and possible surgical intervention, including skin grafting, are considered the natural cost of healing the wound. Healing by primary intention, on the other hand, does not have these issues. Healing by secondary intention was previously used as the only way to heal an open wound. The healing stages were well documented: suppuration, granulation, closure of defect, and skin closure. This was the recommended method of treating contaminated wounds by surgeons until the 1980s. Since the 1970s, however, primary closure of debrided infected pockets has been successfully and almost exclusively used to manage device-related infections.

Direct Traction

All current lead extraction procedures use some form of traction, or pulling force¹³ (Fig. 26-10). Pulling on leads was a successful method of extracting leads during the early years of pacing, when leads lacked efficient fixation devices and were implanted for short periods. Traction was applied manually for minutes or applied using various weights or elastic bands for days. Traction proved unsafe and had a high incidence of failure when applied to leads with efficient fixation devices and leads implanted for longer periods. The amount of traction required increases and becomes more dangerous as the duration of the implant and the tensile strength of the fibrous tissue increase. Leads with efficient passive-fixation devices may be difficult to remove 4 to 6 months after implantation. A failed previous attempt to extract a lead frequently damaged the lead, making future extraction attempts more difficult.

Figure 26-10 Direct traction.

Direct traction is being applied by pulling on the proximal portion of the lead. Rubber bands are used in this case. Variations include using free weights and applying weights with an orthopedic traction apparatus. If a locking stylet is inserted, the traction point is moved distal to the locking site, usually near the electrode.

Again, traction must be applied judiciously to minimize the risk to the patient. The pulling force applied to the proximal portion of the lead is distributed to sites where fibrous tissue binds the lead or electrode and makes contact with the vein or heart wall. Multiple leads may be bound to the vein or heart wall and to each other. Because the pulling force is not focused, the distribution of force to the binding sites is unknown. The extractor may inadvertently tear a vein or the heart wall.

Traction, in some form, is integral to lead extraction. The physician must consciously limit the pulling force and apply a continuous, steady traction. Never jerk the lead, because impulse forces tear. Accidents are not predictable and frequently occur without warning, partly because it is impossible to judge accurately the level of force applied to the lead. To gauge the applied force, most direct-traction techniques apply sufficient force to feel the rhythmic tugging of the heart without producing arrhythmias, hypotension, or chest pain. These are crude and unreliable endpoints and do not reflect the tensile strength of the lead or the tissue. Breaking the lead, tearing a vein, or avulsing or tearing the heart wall are all potential complications. As stated, “just a little tug to see if the lead will come out” is not a consistently safe approach, and following the basic principles and guidelines acquired from practical experience minimizes the risk.

It is important to understand the difference between pulling from above and pulling from below. The mediastinal structures are not bound from below. If you pull upward on the heart, it will move, along with the lungs, diaphragm, and rest of the mediastinal contents, in that direction. If you pull downward, the superior veins and surrounding structures are bound to the musculoskeletal system and do not move downward. Assume that traction is applied from above to a lead implanted in the right ventricle. With continuous traction, the right ventricle starts to evaginate, decreasing the compliance of the wall and finally obstructing the flow of blood through the tricuspid valve. At the same time, the heart is pulled into the superior portion of the mediastinum. This maneuver is safe as long as the hemodynamic status is monitored and the process is reversible. Reversibility means that traction-induced deterioration in hemodynamic function is corrected on cessation of the traction, and the right ventricle, along with remainder of the mediastinal structures, returns to its normal position. Usually, the structures do return to normal. The danger is slippage of the lead body through a binding site. On release of the traction, the mediastinal forces pulling downward are insufficient to pull the lead back through the binding site. The forces required to elevate the mediastinum to this position are still applied to the heart. Any hemodynamic compromise persists, such as decreased blood flow through the right ventricle, creating a cardiovascular emergency. If the lead body cannot be released by manipulation, including use of a stiff stylet to help push it through the binding site, an emergency median sternotomy is required to restore manually the heart’s function.

Once a lead is freed from a distal binding site, the lead and associated fibrous material can then become wedged in a more proximal binding site. For example, a lead removed from the right ventricle can become wedged at a binding site in the atrium, SVC, or axillary-subclavian-brachiocephalic veins. With direct traction, the lead is freed from the binding sites, distal to proximal. The strongest binding site determines the outcome of an extraction attempt, regardless of its proximal or distal location.

Indirect Traction

Elevation of the mediastinum with traction is the main reason why traction from above is not as effective at pulling a lead through a binding site as is pulling from below. When traction is applied from below, the mediastinum is not pulled down (inferior) because the superior veins and surrounding tissues are bound to the musculoskeletal system. Traction forces applied to the binding sites are directed at freeing the lead, not at moving structures. The limit to the force applied to the axillary-subclavian-brachiocephalic veins is determined by the tensile strength of the lead. If the lead binding in these veins is extensive enough to require that type of force, the veins are probably occluded, atretic, or encapsulating sheaths. Disruption of these veins by tearing or avulsion is of no consequence. Binding sites in the SVC, however, must be treated in the same manner as in the heart. Disruption of the wall of the SVC has the same consequences as disruption of the heart wall.

The safety and efficacy (higher success rate) of applying indirect traction from below should now be apparent. Indirect traction is traction applied by an instrument, such as a snare passed into the heart, usually through a femoral vein. The lead is entrapped in the snare, and traction is applied by pulling or pushing. The difficulty is in grasping the lead in a way that allows sufficient traction to be applied. Only a few snares, such as the Dotter basket snare and Needle’s Eye-Snare (both Cook Vascular, Vandergrift, Pa.), or the Amplatz Gooseneck Snare (eV3/Vasocare, Seoul) have sufficient strength to support significant extraction forces. The lead must first be freed from the superior veins and then from the heart. The lead is pulled out of the superior veins and into the atrium or inferior vena cava (IVC). It can be regrasped, if necessary, and traction can be applied to the heart. The techniques for applying indirect traction are the same as for grasping and manipulating the leads in other approaches, such as applying countertraction sheaths, as described later. The risks eliminated by indirect traction are tearing of superior veins, wedging of the lead in the atrium or in a superior vein, and creating a low cardiac output caused by failure of the lead to return to its original position after traction. Indirect traction has the same potential for breaking the lead or tearing the heart wall as direct traction, if their tensile strength is exceeded.

Countertraction

Countertraction is the technique used to free the lead from compliant, encapsulated fibrous tissue. Countertraction was first used to remove a lead from an implantation site in the right ventricle or atrium. Although the technique for extracting leads from the heart wall is discussed first, this is the last step in a normal lead extraction procedure, using any type of sheath. Extraction sheaths free leads from binding sites, proximal to distal. Once the sheath is passed over the lead and down to the implantation site, traction on the lead pulls the site to the sheath (Fig. 26-11). The traction force is countered by the circumference of the sheath. The countertraction sheath focuses the traction force at the tip of the sheath, limiting the excursion of the heart wall. This prevents compliance changes and blockage of the tricuspid valve, with possible perforation, tearing, and avulsion of the heart wall. The countertraction forces are limited by the tensile strength of the lead. At some point, the electrode is freed from the encapsulating fibrous tissue, allowing the heart wall to fall away and the electrode to be pulled out of the sheath.

Figure 26-11 Countertraction.

Countertraction is a safe method extirpating a lead or electrode from a vein or heart wall. Left, Traction on the lead body with evagination of the right ventricular wall decreases the compliance on the wall and pulls it toward the tricuspid valve. Complications include decreased flow through the right ventricle and disruption of the ventricular wall instead of the scar tissue, with tearing of the wall and/or avulsion of tissue. Right, Placing a sheath near the heart wall applying traction causes the traction force to be countered by the sheath. The limit on the traction force applied is the tensile strength of the lead. The lead is extirpated from the scar tissue, and the heart returns to its normal position.

The way countertraction actually frees the lead is postulated but not known. It is thought that the traction force wedges the lead against the countertraction sheath. The pulling force on the electrode tries to evaginate the encapsulating fibrous tissue. The electrode is then freed either by (1) a plastic deformation of the tissue that allows it to slide out of the encapsulating tissue as the countertraction sheath peels the tissue off the electrode or (2) an actual disruption or bursting of the encapsulating tissue that frees the electrode, or both. For a passive-fixation electrode, the tines are removed intact with the electrode; for an active-fixation electrode, the fixation mechanism is ideally retracted or unscrewed before countertraction is applied. In some cases, continued “unscrewing” of an active-fixation lead results in complete lead removal without the need for countertraction, because of the absence of significant binding at other sites along the lead.¹⁴ If the helix will not retract, the electrode and fixation mechanism are removed together. The same scenario likely applies to removal of electrodes from the atrial wall.

Countertraction is also used to free the lead from the encapsulating fibrous tissue at binding sites along the vein and heart wall (see Fig. 26-11). This is possible only if the encapsulating fibrous tissue still has plastic qualities (compliant). The tissue at the binding site is pulled against or into the sheath and is removed by evagination, peeling, or tissue rupture. Countertraction can be performed with either the inner or the outer sheath.

Counterpressure

Counterpressure was the term given to the removal technique used for noncompliant, encapsulating fibrous tissue (mineralized tissue). A sheath larger than the solid encapsulating tissue is used, and the tissue is pulled into the sheath. The encapsulating fibrous tissue is usually attached to the vein, tricuspid valve, or heart wall. The sheath counters the traction force applied to the tissue mass by converting this force into a pressure concentrated locally between the edge of the sheath and the vein wall (counterpressure sheath). This local action peels the calcified mass off the vein or heart wall. The encapsulating tissue is included with the lead inside the sheath (inclusion). The force applied is limited by the tensile strength of the lead and the wall. Because the magnitude of the counterpressure force actually focused on the wall is unknown, application of force is subjective. Counterpressure is potentially dangerous and should be approached with caution. Some believe that mineralization of tissue may lead to a higher risk associated with lead extraction.

The inability to pass a binding site safely using counterpressure is the primary reason for abandoning this approach and changing to a transfemoral or transatrial approach. These approaches allow the lead to be pulled out of the superior veins from below, through the binding site.

It is unknown whether the lead is being removed by countertraction or counterpressure (Fig. 26-12). In the past, counterpressure was used to describe the removal of tissue from all sites other than the electrode implantation site. In most cases, removal is still credited to counterpressure; compliant tissue is removed primarily by countertraction, and noncompliant tissue by counterpressure. Not discussed are leads bound to one another by the calcified encapsulating tissue. Separation of the two leads is safe, and the traction force is limited only by the tensile strength of the lead.

Figure 26-12 Mechanical and powered sheaths.

Telescoping sheaths are inserted transvenously and passed to the first binding site. Countertraction, counterpressure, and/or power ablation is applied to extirpate the lead. Countertraction dilates and/or ruptures the binding site, liberating the lead. The laser and electrosurgical dissection sheath (EDS) is a powered sheath that vaporizes the tissue. Counterpressure is used to pass the sheath over the entire calcified encapsulating fibrous tissue mass (inclusion). Counterpressure is the actual manipulation of the telescoping sheaths to peel the encapsulating tissue off the vein or heart wall.

Mechanical Sheaths

Mechanical sheaths are telescoping sheaths made of Teflon, polypropylene, or stainless steel (Fig. 26-13). These telescoping sheaths are designed to pass over the lead, which acts as a rail guiding the sheaths through the veins and down to the heart wall. Countertraction and counterpressure are applied as the sheaths move down the lead from one binding site to another. The outer sheath also acts as a workstation, facilitating the free movement of the inner sheath and lead by eliminating binding, and it protects the surrounding vascular structures. The leading edges of the sheaths are beveled. The rotation of the beveled tips facilitates maneuvering past obstructions and through the narrow channels along the tortuous paths surrounding the lead body. This is especially true in the superior veins. For the sheaths to pass down the lead in a true course, the lead must be stiff enough to act as a guide rail. The lead is stiffened by pulling it taut. The lead must be stiff enough to resist bending or kinking as the sheaths are passed over it (lead stiffness > sheath stiffness). The telescoping action of the sheaths allows the suppler inner sheath to track over the lead. The larger outer sheath is then advanced using the combination of taut lead and inner sheath as the guide rail. The lead is made taut by traction (pulling on it). A locking stylet is inserted, and a suture is usually tied to the lead, acting as both an extender and a traction handle.

Figure 26-13 Mechanical sheaths.

Telescoping sheaths have a beveled tip and come in various sizes. A, The original Teflon sheaths are softer and suppler. B, Polypropylene sheaths are stiffer and allow more force to be applied at the binding site. C, Stainless steel sheaths are rigid and are used to bore through bone or calcified tissue at the vein entry site. The stainless steal sheaths should not be passed into the brachiocephalic vein.

As described earlier, experience and judgment are required to avoid tearing and avulsing vein and heart wall tissues. Also, if the traction force exceeds the lead’s tensile strength, it can cause lead disruption and breakage. Insertion of a locking stylet adds some stiffness to the lead and focuses the traction force to a locking site near the electrode. Except for simple cases, in which leads have been implanted for a short duration, a locking stylet should be inserted. Despite these provisions, when there is poor tensile strength of the lead, it is more difficult and more time-consuming to free the lead from its binding site. The forces involved frequently exceed the tensile strength of the lead, unless there is a good locking stylet and suture, resulting in lead disruption and breakage.

Electrosurgical Dissection Sheaths

The EDS has two bipolar electrodes positioned at the tip of the bevel (Fig. 26-15). The sheath is connected to an interface plate inserted on a conventional electrosurgery unit (Valley Lab Force V; PEMED, Denver), placed in a bipolar cutting configuration, and activated with a foot switch. The interface plate is attached to the front panel of the electrosurgical unit to ensure that the EDS is connected in a bipolar configuration. The interface also has an attachment to pulse the electrosurgical unit 80 times per minute. A plasma arc is generated between the electrodes. The plasma arc extends out from the electrodes and vaporizes the tissue to a depth of about 1 mm. On continuous discharge, desiccated tissue debris shunts the arc between the electrodes, preventing it from cutting. Also, on continuous discharge, if one of the electrodes touches a conductor coil, a parallel, alternate current (AC) circuit is created consisting of the EDS electrode in contact with the conductor coil, the conductor coil down to an electrode in the heart, and back to the other EDS electrode. An AC current applied to the heart in a unipolar configuration can fibrillate the heart. To ensure cutting and avoid fibrillating the heart, the EDS is operated in a pulsed mode at 80 pulses/min. In the pulsed mode, if a conductor coil is touched, it paces the heart.

Figure 26-15 Electrosurgical dissection sheath (EDS).

The EDS is a telescoping, beveled Teflon sheath set with two electrodes in a bipolar configuration at the tip of the inner sheath. Encapsulating tissue is ablated with pulsed radiofrequency energy delivered as needed at 80 Hz. The electrodes are radiopaque, allowing precise placement.

The EDS is a conventional Teflon mechanical sheath with two tungsten electrodes embedded in the polymer. Placement of the EDS electrodes in a bipolar configuration at the tip of the inner telescoping sheath endows the EDS sheath with properties of mechanical sheaths; it can maneuver through tortuous veins and can apply countertraction and counterpressure. These sheaths are currently available in sizes 7F, 9F, 11F, and 13F (circumference of inner sheath).

The electrodes and sheath are radiopaque, allowing visualization during fluoroscopy. The electrodes’ position is continuously adjusted by rotation of the sheath. For example, around a curve, the electrodes are placed on the inner curvature passing down the lead. Also, the electrodes are rotated away from skeletal muscle and nerves to avoid stimulation. Stimulation of skeletal muscle or the phrenic nerve does not harm the patient and is not an issue with general anesthesia. However, skeletal muscle and diaphragmatic contractions can be discomforting and even frightening if the patient is awake. At present, this is the only clinical issue associated with the EDS. The same emergency precautions applicable to mechanical and laser sheaths also apply to the EDS.

Clinical evaluation of the EDS has been formally published only in an observational study from five centers, involving 265 patients with extraction of 459 leads.²⁰ During the investigation, only the 9F and 11F sheaths were used, excluding almost all ICD leads from consideration for extraction. As in all extraction series, some of the leads came out easily and others were more difficult to remove, and the techniques consisted more of an approach than of universal use of one tool to remove all leads. In this case, 542 leads were potentially presented for extraction, but about 15% were removed with direct traction, yielding 459 for which the EDS was employed. The laser tool was used in fewer than 3% of the leads. The average implant duration of the patient’s oldest lead was 8.4 ± 5.0 years; 31% of patients had leads implanted for longer than 10 years. Major complications occurred in 2.6% of patients, including cardiac tamponade in 4 patients (1 surgical repair, 1 after switching to a femoral approach), 1 hemothorax, 1 arteriovenous fistula (surgical repair), and 1 death that was associated with the mechanical removal of an oversized SVC lead for which the EDS was not used. For the 459 leads with attempted removal by the EDS, 99.4% were removed (95.9% completely, 3.5% subtotally with ≤4 cm of lead remaining), and only 0.6% were not removed.

Overall, the experience with the EDS has been good. The application of 7F and 13F sheaths with intermittent pulsing of the electrosurgical energy has been useful in removing smaller and larger leads and in making the sheath more powerful in cutting through the fibrosis.

Evolution Sheath

A newer mechanically powered lead extraction sheath set is the Evolution mechanical dilation sheath (Cook Vascular). A rotating inner sheath with a threaded-barrel metal tip is designed to function as a dilating drill (Fig. 26-16). This bores through the encapsulating fibrous tissue as it advances down the lead through the binding sites. The outer sheath is a conventional, beveled plastic sheath. The rotation of the inner sheath is powered by a pistol-grip handle squeezed by the operator (mechanical power). Multiple inner diameter (ID) sizes (7, 9, 11, and 13 French) are available. The initial experience with the Evolution had mixed results.²¹ There was a high procedural and clinical success rate. The Evolution is particularly useful as a rescue when heavy calcifications are encountered while using the laser sheath. There was a tendency toward wrapping of adjacent leads and also collateral damage to the leads not intended for extraction. The system seems to work best in single-lead systems when collateral damage or wrapping is not an issue. No complications resulted from use of the Evolution.

Figure 26-16 Evolution mechanical dilator sheath (Cook Vascular).

Locking Stylets

Locking stylets were developed after the mechanical sheaths. From the beginning, the major pacing companies (Medtronic, Cordis, Pacesetter [St. Jude Medical], and Boston Scientific [Guidant, CPI]) all attempted to make a universal locking stylet (one size stylet to fit all leads). These initial attempts were unsuccessful because of breakage of the locking mechanism. The tensile strength was inadequate to withstand the traction forces. Cook Pacemaker (now Cook Vascular) took another approach, abandoning the concept of a universal stylet. Their first-generation locking stylet came in various sizes to fit a variety of conductor coil diameters (Fig. 26-17). The conductor coil had to be measured before selecting the locking stylet. This locking mechanism was a small wire welded to the tip of the stylet and wrapped around the lead. Once the lead was passed down the conductor coil to the electrode, it was rotated counterclockwise, bundling the free wire and causing it to bind against the conductor coil. The greater the traction, the greater was the binding force. The locking stylet bound to the inner conductor coil, ideally at the distal electrode, functioned as a lead extender for applying traction and focused the traction force at the binding site. Focusing the traction force helped maintain the integrity of the lead but did not prevent lead disruption if excessive force was applied or if the lead had poor tensile strength. Also, the locking stylet was conductive, and the heart could be paced during parts of the lead extraction procedure if needed. This was the first effective locking stylet.

Figure 26-17 First-generation locking stylet (Cook).

A, Ideally, the locking stylet is passed to the electrode and secured. The locking mechanism is a wire that is secured to the tip and wrapped around the stylet. B, When the stylet is turned counterclockwise, the wire bundles together, binding the stylet to the conductor coil. The locking stylet acts primarily as a lead extender to apply traction and secondarily to keep the lead intact during the extraction. When the stylet is positioned at the electrode, the lead has its best chance of remaining intact. If the stylet is positioned near the proximal end, the fragile leads will be pulled apart when traction is applied. C, Clockwise from lower left, Locking stylet, sizing pin, lead cutter, coil expander, soft-grip hemostat, standard stylets, and polypropylene telescoping sheaths.

Cook’s second-generation locking stylet (Wilkoff Locking Stylet) had a different locking mechanism (Fig. 26-18). These stylets had a small flange at the tip designed to stay flat against the stylet until the preloaded thin cylinder was advanced; the cylinder deflected the flange to lock into the conductor coil. This was an efficient locking stylet that was easy to implant and that could be removed by rotating the stylet, breaking the flange. However, it could not be used if the conductor coil diameter was 0.016 inch or less, and it could not be used with extendable/retractable screw-in leads. Spectranetics made the first near-universal locking stylet (Lead Locking Devices 1, 2, 3 and e) to fit all leads. It used a long wire mesh that bundled and bound the stylet to the conductor coil. This type of locking stylet was efficient and functioned well. Ultimately, the Spectranetics LLD-EZ was developed that works for all but a few leads with extremely small IDs to the inner coil.

Figure 26-18 Second-generation locking stylet (Cook).

The Wilkoff Locking Stylet employs a different mechanism for applying traction to the lead conductor at the tip of the lead. It also functions as a lead extender to lengthen the lead so that the sheaths can be advanced to the endocardial surface. The locking mechanism does not require precise measurement of the internal diameter of the conductor coil, and each size of the Wilkoff stylet bridges three sizes of the original locking stylet. The mechanism is activated by advancement of the thin cylinder, which nudges the hook to the side, engaging it between the coils of the conductor. This mechanism can be reversed and relocked but does not tolerate rotation. The response to rotation can be an advantage if the stylet needs to be removed.

Cook’s most recent, third-generation locking stylet (Liberator Locking Stylet) is a true universal locking stylet (one size fits all). It uses a wire coil that is compressed by a reloaded cylinder, expanding the wire coil and binding it against the conductor coil (Fig. 26-19). Both the Liberator and the LLD-EZ are extremely versatile and provide an advantage over the alternative for either advancement down the conductor coil in locking.

Figure 26-19 Third-generation locking stylet (Cook).

The universal locking stylet works by binding the locking stylet to the conductor coil. A wire coil is ideally positioned at the tip of the lead, near the distal electrode. The coil is expanded, binding the stylet to the lead’s inner conductor coil. Traction increases the binding force. A stylet now can fit the smallest conductor coil and still have sufficient tensile strength to support a wire coil large enough to bind to the largest-diameter conductor coil. A, Lead conductor without the locking stylet. B, The liberator locket stylet has been advanced to the tip of the lead. C, The cylinder is pushed to crush the wire coil at the tip of the lead, locking to the conductor. D, Comparison of the inner wire with and without the wire coil at the tip of the universal or liberator locking stylet.

As mentioned earlier, the goals for inserting the locking stylet were to provide a lead extender and to focus the traction force at the tip to help maintain lead integrity. Although these goals were met, the insulation still has to be secured with a suture. Without traction to the insulation, it can “snow plow” and tear more easily, making passage of the extraction sheaths difficult, and in some cases preventing their passage. Therefore, traction should be applied to both the suture (insulation) and the locking stylet (conductor coil) to be most effective.

A new tool, the Bulldog lead extender, is designed for leads that have no conductor coil, or when the conductor coil is severely damaged. It mechanically locks onto the conductors to the shocking and pacing electrodes and produces an excellent mechanism for improving the tensile properties of the lead. The Bulldog can also be used to lock onto the cables to the shocking coils in leads with a cylindrical conductor coil, and a locking stylet is still used in the cylindrical coil.

Snares

Snares are used to grasp leads and to remove tissue in the bloodstream from the vein or transatrial entry site. The vein entry sites typically used are the subclavian, internal jugular, and femoral veins. Only a few snares are safe to maneuver in the cardiovascular system or have the tensile strength to support the forces involved in a lead extraction procedure. The Dotter snare, Needle’s Eye Snare (Cook), and Amplatz Goose Neck Snare are discussed as examples of the types of snares available. The Dotter snare, together with a deflection catheter, is prepackaged in the femoral workstation. Before the availability of powered sheaths, lead breakage and the need to use a femoral approach were common. The only substitute for a snare is a cardiac surgical procedure. Consequently, facility with snares still is a requisite skill. Also, there are still extractors who do not use powered sheaths, relying only on the mechanical sheath extraction, and snares are integral to these procedures.

With the Dotter, needle-eye, and gooseneck snares, a reversible loop is created around the lead body to pull the proximal end of the lead out of the superior veins into the IVC, without placing traction on the electrode-myocardial interface (Fig. 26-20). A loop must be created and bound to the lead body. The binding of the loop must be reversible. Irreversibly binding the lead, or inability to remove the loop from around the lead, may result in dangerous traction maneuvers being performed in desperation while trying to extract the lead and snare. Failure to extract the lead subjects the patient to more invasive procedures to remove both lead and snare.

Figure 26-20 Femoral workstation (Cook).

The Byrd WorkStation has two snares (Dotter basket and Cook deflection), the first that we found to have the versatility and tensile strength suitable for lead extraction. A, Telescoping Teflon sheaths and Dotter snare advanced to the right atrium with lead body entangled in the snare. Pulling the lead into the sheaths for lead extraction is possible but not recommended because it is not reversible. B, Dotter snare and deflection catheter in atrium. C, Looping the lead body with the deflection catheter. D, Entangling the tip of the deflection catheter in the Dotter snare. E to G, Tightening the loop and pulling it into the Teflon sheaths. H, Sliding the telescoping sheaths to the electrode for removal using countertraction. At any time, the process can be reversed, freeing the lead.

Creating a reversible loop using two snares is a complicated maneuver requiring practice to perfect. One technique is to use a Cook deflecting wire guide and a Dotter basket snare. The Cook deflecting wire guide is wrapped more than 360 degrees around the lead body. Next, the tip of the deflection catheter is passed into the Dotter basket snare. When the basket snare is pulled into the workstation, the basket closes, grasping the deflection catheter and completing the loop. The loop is pulled into the workstation, tightly binding the lead body to the workstation, and traction is applied. If needed, the loop is relaxed and repositioned on the lead body. This sequence is repeated until the lead is pulled out of the superior veins, through the right atrium, and into the IVC. The reversible loop is then released, and the deflection catheter is removed. This same process can be done with a gooseneck snare and tip deflecting guidewire or a deflectable EP catheter and gooseneck snare.

The Cook Needle’s Eye Snare is a more efficient method of grasping the lead in a reversible manner (Fig. 26-21). This snare has a wire loop that is passed over the lead body. A small, wire-loop tongue is then passed over the opposite side of the lead and into the larger wire-loop tongue. Pulling this apparatus into the workstation binds the lead reversibly for safe, indirect traction. Also, the binding forces are more diffuse, resulting in less lead breakage.

Figure 26-21 Cook Needle’s Eye Snare.

This is the only reversible snare designed specifically for removing leads. A, The lead body is hooked, usually in the atrium, and the tongue is extended, forming a reversible loop. B, The lead body is pulled into the telescoping sheaths for lead removal.

The Amplatz Goose Neck Snare is a radiopaque noose that is slipped over the free proximal end of a lead (Fig. 26-22). In situations where the proximal end is floating in the SVC, heart, or a pulmonary vein, the free end can be lassoed and extracted. The gooseneck snare can also be used to grasp the end of a tip-deflecting guidewire or deflectable EP catheter draped over the midportion of the lead. This is an excellent technique to reposition a lead so that the end can be grasped after being pulled down from the subclavian/jugular system, or to grasp the lead reversibly for extraction.

Figure 26-22 Amplatz Goose Neck snare.

A to D, The gooseneck snare places a noose around the end of a lead and is pulled taut. The gooseneck assembly is then pulled into telescoping sheaths for lead removal. This snare is reversible unless the assembly binds in the telescoping sheaths. In our experience, this snare is most effective for removal of small lead segments (e.g., electrodes, lead body segment) from small vessels such as hepatic veins, pulmonary arteries, azygos veins, and pelvic veins.

Lead Vein Entry Site

A transvenous approach through the lead vein entry site is a natural approach. After the pocket debridement procedure, which includes freeing the leads to near the vein entry site, it is natural to continue and remove the lead from this site. In some situations, the lead is broken or cut and retracted into the axillary-subclavian-brachiocephalic veins. If this lead can be grasped by an instrument passed into the vein and exteriorized, it is then considered to be a lead passing through the vein entry site, for purposes of this discussion. The lead can be extracted by direct traction, if applicable, or by a mechanical or powered telescopic sheath. Most extractors currently use this natural approach. Working through the vein entry site is efficient and subjects the patient and physician to the least amount of radiation, with the fewest maneuvers and least time required. Radiation exposure is related to the amount of fluoroscopy time. Also, once the lead is removed, a new lead may be readily inserted through the conduit created during the extraction.

As previously discussed, direct traction is applied by pulling directly on the lead manually, with a suture or locking stylet or both. Indirect traction refers to grasping the lead with a snare and applying traction by the snare. Some leads are easily removed by direct traction.

The vein entry site is not always easily accessed. In some situations, the lead is entrapped in calcified encapsulating tissue and cannot be entered using the nonmetal extraction sheaths, with or without power. The cause of the calcified encapsulating tissue at the vein site is usually related to introducer technique. If the introducer needle scores the clavicle or first rib, elevating the periosteum, the periosteum will re-form about the lead, entrapping it in a bone sheath. If the introducer needle passes through the costoclavicular ligament, this damaged tissue will mineralize and entrap the lead. Natural maturation of a thrombus into fibrous tissue, which mineralizes with time, also may create this problem. Usually, however, the problem is associated with the periosteum and costoclavicular ligament, and metal sheaths are used.

Telescoping stainless steel sheaths look dangerous but are safe and effective if properly used (see Fig. 26-13, C). The principle is simple: keep the sheaths “tracking true” over the lead, and apply the force needed to destroy this tissue. A combination of pushing and rotation of the beveled tip is most effective. Once the metal sheaths break into the vein, they are removed and replaced by plastic extraction sheaths. “Tracking true” is a principle used for all sheath maneuvers. All sheath maneuvering must be performed under fluoroscopy, to ensure that the sheaths are tracking over the lead. Any kinking or other deviation of the vein course is dangerous. It creates a false passage that may be extravascular and may damage nearby structures.

Remote Vein Sites

A remote vein site is a vein other than the lead vein entry site. A remote vein site requires a remote instrument, such as some type of snare, to manipulate the lead. The femoral vein was the first remote vein site used. During the early evolution of lead extraction, removing leads with mechanical sheaths from the superior veins through the vein entry site was frequently a failure and potentially dangerous. A more difficult approach through a femoral or other remote vein site was more effective and safer. The problems were related to maneuvering the long, telescoping mechanical sheaths from the femoral vein to the heart wall and the complexities associated with grasping the lead body. With the advent of powered sheaths, the safety and efficacy of removing leads from the vein entry site improved dramatically.

Although most of the leads can be removed from the vein entry site, there are still dangerous situations and lead breakages. In these cases, a remote vein or a transatrial surgical procedure are the only options. In many cases, the femoral vein approach is still the best remote vein approach. However, other remote veins (contralateral external jugular, internal jugular, or axillary-subclavian-brachiocephalic) may be more suitable and easier to use. Some physicians have developed combination approaches, applying mechanical sheaths from both the vein entry site and a remote vein site. This combination constitutes a safe and efficacious approach, as developed by Bongiorni et al.,²² and has become increasingly popular, particularly when the need for reimplantation through the original venous access is no longer required. For cases such as lead breakage, use of a snare to grasp the lead and the subsequent removal of the lead using direct traction or a powered sheath is advantageous. Powered sheaths are not long enough in moderately tall patients for a femoral approach. Consequently, these approaches are confined to the superior veins, via both remote and vein entry sites.

The techniques used involve manipulation of snares to grasp the lead body. Although these techniques are simple in principle, they can be difficult to achieve in a timely fashion. Initially, there were no snares designed for lead removal, so a suitable off-the-shelf snare designed for other purposes (“off-label”) had to be found. The criteria for such a snare included the tensile strength to withstand the forces applied during lead extraction, safety of the surrounding tissue when maneuvering the snare, and reversibility of the grasping mechanism. The Dotter snare was the first snare to meet the tensile strength requirements. When the Dotter snare was combined with the Cook deflection snare, the safety and reversibility requirements were met. Later, two snares were manufactured meeting these requirements: Cook Needle’s Eye Snare and Amplatz Goose Neck Snare, which are still in use (see earlier discussion). Angled, pigtailed angiographic catheters, endsnares, bioptomes, and every conceivable catheter has been used to good effect for some patients. Thus the principles of use are more important rather than the precise tool.

A classification of remote vein approaches deviates from the historic use of the IVC (femoral vein) approach. A natural classification is to employ the removed vein (e.g., femoral approach, internal jugular approach). Remote vein site use is discussed here based on this natural classification. The goal is the same as for the vein entry discussion: to define the approach, procedure techniques, and expected results in relation to the pathology and pathophysiology associated with the implanted lead.

Femoral Approach

As discussed earlier, before the advent of powered sheaths, the femoral approach was used extensively. The indications for its use were failure to extract leads from the superior veins by any technique, lead breakage, and avoidance of the application of excessive force with the mechanical sheaths. The techniques used have not evolved significantly over the past 15 years. The transvenous approach through a femoral vein requires a special sheath set (e.g., Byrd WorkStation) that functions as an introducer, as a workstation for manipulation of snares, and as countertraction sheaths (Fig. 26-23). The set consists of an introducer needle, a guidewire, a 16F workstation, an 11F tapered dilator, an 11F telescoping sheath, a Cook deflection snare, and a Dotter basket snare. The workstation serves many functions. Initially, it acts as a protective sheath. The outer sheath prevents the insertion, withdrawal, and manipulation of the inner sheath and snares from damaging the veins or heart. To prevent clot formation, the workstation has a valve (Check-Flo) to continuously irrigate the sheath. The workstation and snares form a reversible loop to pull the proximal portion of the lead out of the superior veins; the workstation also acts as the outer telescoping countertraction sheath.

Figure 26-23 Byrd Femoral WorkStation (Cook).

Telescoping sheaths are passed to the heart. The outer sheath functions as a workstation protecting the vein and heart wall during maneuvering of the inner sheath. Once the lead is secured by the reversible loop, the sheaths are advanced to the electrode to apply countertraction. The workstation is packaged with telescoping sheaths, guidewire, and dilator to be inserted as an introducer. The dilator is removed and the snares inserted.

The safe insertion and removal of the workstation is a prerequisite for an extraction procedure through a femoral vein. The workstation is 16F and must be inserted with care. Fluoroscopic monitoring is mandatory. Once the guidewire is passed into the heart, the workstation with its tapered dilator must be maneuvered through the iliac vein and IVC and into the right atrium. The route can be circuitous, especially from the left side. In rare cases, the curvature may be too sharp for the stiff dilator to follow the guidewire. Forcing the dilator in this situation is unsafe, and the approach should be abandoned. A torn retroperitoneal iliac vein or IVC is a serious complication. Once the workstation is inserted, irrigation fluids are run continuously through the Check-Flo valve to prevent clotting.

Pulling leads down and out of the superior veins has been remarkably successful. Many leads freed from the heart cannot be pulled up through these same veins. The lead binding forces caused by the circumferential bands of fibrous tissue are the same in both directions. The hypothesis for this difference is the free upward mobility of the mediastinal structures and the inability to pull the superior veins downward. The mediastinum is easily pulled upward, compressing the veins. This compression of the fibrous tissue bands around the lead as they bunch together is postulated to increase the binding strength. The superior veins cannot be pulled downward, and irreversible lead slippage through the binding sites is not an issue. Cardiac function is not influenced by pulling leads downward out of the superior veins. Failure to extract the proximal lead from the superior veins using this technique is rare and usually caused by other complicating factors, such as thrombosis of the superior veins and excessive fibrosis around the lead caused by a previous extraction attempt that left the conductor coil exposed or pulled the lead taut against the heart and vein wall. Such leads are removed using approaches (e.g., transatrial) reserved for more complicated extractions.

To apply countertraction through the workstation, the proximal end of the lead must be entangled in the basket snare. This is accomplished by placing the basket snare close to the lead and rotating it slowly. The lead will flip into the basket. The basket closes when the 11F sheath is advanced over the snare. For most leads, the snare and lead are pulled into the 11F sheath. The workstation and 11F sheaths are then worked in a telescoping fashion to a point near the electrode. At this point, countertraction is applied to extract the electrode, as previously described. Removal of the workstation must be carefully performed. Once the lead is extracted, clot and debris may be attached to the end of the tubing. If this material dislodges in the femoral vein entry site, it can act as a nidus, forming a thrombus or initiating thrombophlebitis and its sequelae. To prevent this complication, blood is aspirated during the withdrawal of the workstation. If the entry site does not bleed freely after withdrawal of the workstation, a surgical exploration of the vein is recommended. Bleeding is controlled by applying pressure over the vein entry site after withdrawal of the sheath and during Valsalva maneuvers induced by the anesthesiologist. A suture or staple is required to close the skin. A potential complication is thrombophlebitis and pulmonary embolus. Concern about this complication was the incentive for the workstation. Postoperatively, anti-embolic stockings (pneumatic, if possible) and subcutaneous heparin (5000 units twice daily) are the only precautions taken.

The technique for grasping the lead in a reversible loop using a Cook deflection catheter and a Dotter snare or with other tools is more complicated. Once mastered, it is an effective method of performing precision extraction. For example, a patient may have six leads in the heart. Two new leads are connected to a pacemaker and are to be saved. Four leads are abandoned and are to be extracted. The abandoned atrial and ventricular leads can be extracted, leaving the newly implanted leads intact. The IVC approach allows this level of precision.

Superior Vein Approaches

The other transvenous approaches include the external, internal jugular, and axillary-subclavian-brachiocephalic veins, usually on the contralateral side. The telescoping sheaths used with the femoral approach are mechanical (powered sheaths are not available). The creation of a conduit by the powered sheaths from the vein entry site encourages the use of snares passed through these sheaths to remove leads (e.g., broken, free-floating leads). A snare is used to grasp the lead, and if needed, sheaths are passed over the snare to the lead. The difference is in the extraction tools available. For example, the femoral workstation is too long and is not applicable for the superior vein approaches. Using standard introducer techniques, a guidewire is inserted and telescoping mechanical sheaths are passed into the SVC or heart. These sheaths then act as a workstation for passage and manipulation of a snare. The same snares used for the femoral approach are usable with the superior vein approaches. The Needle’s Eye Snare has a shorter, simpler version for the superior veins. Once snared, the lead can be removed using indirect traction, mechanical sheaths, or powered sheaths. The noose snares are also effective from the superior approaches. All the principles and guidelines for lead extraction apply to these approaches.

Combined Approaches

To some degree, most remote approaches are a combination of a lead vein entry site and a femoral vein approach. An extensive effort may have been used to free the lead from the superior veins; this was always in preparation for the intended use of the remote approach. From its inception, some physicians championed the use of a combined approach. Initially, the vein entry approach and femoral vein approach were combined, sometimes with two teams working, one for each approach. The goal was to free the lead by applying the extraction techniques from both approaches and removing the lead in an opportunistic fashion (the resultant easiest approach). The electrophysiologist might work from the vein entry site and a radiologist from the femoral vein site. Although successful, this approach was overkill for most lead extractions, especially once powered sheaths became available.

A combination of the vein entry site approach and a right internal jugular approach is used by some physicians as their primary approach to lead extraction. They use snares and/or a grasping instrument passed through the internal jugular vein into the SVC to pull the lead out of the axillary-subclavian-brachiocephalic veins and, if necessary, to pull the lead into the atrium. Mechanical sheaths are then applied to complete the extraction (to date, powered sheaths are not used).²³

The techniques used with remote approaches can be applied through the vein entry site. A lead may have broken or been cut, retracting into the axillary-subclavian-brachiocephalic veins, floating in the SVC or heart, or migrating into the pulmonary veins. If the lead can be reached and grasped inside the axillary-subclavian-brachiocephalic veins by a surgical instrument, it can be pulled out of the vein entry site and secured with a suture or a locking stylet, or both. The lead can then be extracted using the vein entry approach. If the lead cannot be grasped by an instrument but a snare can be passed into the SVC from the vein entry site or a contralateral vein, the lead is grasped and removed using mechanical and/or powered sheaths. Before powered sheaths became available, the femoral approach was common, but now it is rarely used. Surgical electrophysiologists have the transatrial approach as a viable alternative. Regardless of the frequency of use today, the transfemoral approach is a requisite procedure for managing device-related complications.

Transatrial Approach

The transatrial approach, first described by Byrd in 1985, is a surgical EP procedure suitable for intracardiac implantation, explantation, and ablation procedures.²⁵ The only disadvantages are the morbidity associated with surgical thoracic pain and the need for a medical electrophysiologist to work with a cardiac surgeon. It is a primary approach for noninfected patients who are candidates for a transatrial lead implantation. Younger patients with occlusion of one brachiocephalic vein or with SVC syndrome have the old leads extracted through a transatrial approach, followed by implantation of new leads. The advantage of the transatrial approach is the ability to remove leads that are not accessible or removable by the SVC or IVC approach. Most of the transatrial extractions are failures of the IVC approach. Rarely, failure of an SVC approach will lead directly to a transatrial approach (e.g., when the workstation cannot be passed through the femoral veins into the heart). Infected patients who are candidates for transatrial lead implants will have the leads extracted by an SVC or IVC approach and the transatrial implantation done after the infection is properly treated.

The transatrial approach is performed as originally described, through a limited surgical incision on the right anterior chest wall (Fig. 26-24). The right atrium is exposed by removal of the third or fourth right costal cartilage (determined by fluoroscopy). The pericardium is opened and suspended, and a pledgeted purse-string suture is placed in the right atrium. If the pericardium has been obliterated from a previous procedure or disease process, a small region of the lateral wall of the right atrium is dissected free. Using fluoroscopy, a pituitary biopsy instrument is inserted through the purse-string. The lead body is grasped in the atrium and pulled out. The lead is then cut, extracting the proximal and distal segments separately. The proximal portion of the lead can usually be pulled out by direct traction. The only limitation to the force employed is the tensile strength of the lead. In occasional cases where the tensile strength is insufficient, telescoping powered sheaths may be required. The distal segment is extracted by inserting a locking stylet, advancing telescoping powered sheaths to the wall, and removing the electrode from the wall using countertraction. This procedure is repeated for each lead to be extracted. On completion of the lead extraction, the atriotomy site is used to insert new leads, or to perform another EP procedure, or the purse-string suture is tightened, tied, and abandoned.

Figure 26-24 Transatrial approach.

This is a minimally invasive cardiac surgical approach. The third or fourth cartilage is removed, and a purse-string suture is placed in the right atrium. A pituitary rongeur is inserted through the atriotomy incision and used to grasp the lead. The proximal portion of the lead body is removed from the superior veins by direct traction, and the distal lead is removed by mechanical or powered sheaths and countertraction.

After transatrial extraction, patient management is more involved than for the transvenous extraction techniques. The pericardium must be drained, in most cases by a closed-drainage system such as a chest tube, if the pleural space is free; by a mediastinal tube, if the pleural space is obliterated; or by a Jackson-Pratt closed-drainage system, if both the pleural and pericardial spaces are obliterated. The thoracic cavity is occasionally entered and a chest tube inserted to drain both the pericardium and the pleura. These drainage tubes are removed in 2 to 3 days. The procedure-related morbidity increases the hospital stay by 1 or 2 days, compared with a transvenous procedure. Patients must be managed in an intensive care setting until the thoracic pain sequelae are controlled.

Right Ventriculotomy

A right ventriculotomy is a cardiovascular surgical procedure. This approach is rare. Because this procedure is virtually unknown, a cursory discussion of indications for use is in order. Initially, it was reserved for infected broken leads retained in the right ventricle that were not reachable by the other approaches. These are fragile leads that break near the ventricular wall or within a fibrous tissue tunnel along the ventricular wall and are impossible to grasp using transvenous or transatrial techniques. It is also used with lead penetration requiring lead removal and a repair of the heart wall, and possibly for an emergency tear in the ventricular wall caused by an attempt to remove a lead. In the latter, the defect is turned into a ventriculotomy site for lead extraction.

The first ventriculotomy procedures were performed by Byrd in the late 1980s. The heart is exposed through a median sternotomy incision. The heart is then elevated on a pad, exposing the right ventricle. The tip of the electrode is localized by fluoroscopy and by using needles for triangulation of the electrode. A purse-string suture is placed around the electrode, and a ventriculotomy incision is made to the electrode. The electrode is grasped with a clamp and pulled out of the heart. Because the lead segment is being pulled in the direction of the tines, the tines slip out of the embedding scar without resistance. At present, the procedure is performed through a minimally invasive incision on the anterior surface of the left chest through the fifth intercostal space. The purse-string and extraction techniques are the same. This is a stressful procedure for the surgeon, and number of procedures performed to acquire some comfort level is unknown. As long as a need exists for right ventriculotomy, attempts will continue to perfect it.

Open-Heart Procedure

The concept of using CPB to perform an open-heart procedure is intuitively obvious. It is a standard cardiac surgical procedure involving a median sternotomy incision. Right-sided leads were initially removed by direct traction and under direct vision during OHS. Transvenous and transatrial lead extraction techniques evolved to eliminate the need for an OHS procedure.

Implantation of leads in the left atrium and ventricle is a notable exception (Fig. 26-25). Leads are implanted into the left ventricle in two ways: through a congenital atrial or ventricular septal defect or retrograde through the aortic valve. All physicians consider the presence of left-sided leads and embolic symptoms an urgent indication for lead removal. Most consider their presence, with the potential for a complication, to be an urgent indication for lead extraction. A few physicians believe that, in the absence of complications (cerebrovascular accident, coronary artery occlusion, infarction of another organ, or sequelae of peripheral embolus), leaving the leads intact is an acceptable option. The rationale is that the extraction procedure is more dangerous than the presence of left-sided leads. The views on lead removal are just as varied. Some believe the leads should be removed; the chambers debrided of vegetation; and congenital defects, if present, repaired with CPB. Others think it is safe to extract the leads using the established right-sided techniques and protecting the brain from emboli by compressing the carotid arteries when necessary. If the second approach has any merit, it would be in removing newly implanted leads. If the newly implanted leads are proved to be free of vegetation and the procedure is monitored using TEE, it is probably safe to extract using direct traction. Specific data are not available on the numbers of physicians using these opinions.

Figure 26-25 Left-sided implantation.

Transvenous implantation in the left atrium and/or ventricle or a transarterial implantation through the aortic valve into the left ventricle is rare. Left, Transvenous implantation through an atrial septal defect (ASD), such as a sinus venosus defect, is the most common approach. The anatomy guides the leads into the left atrium. Extraction of these leads is dangerous because of the potential for an arterial embolization of debris. Right, We perform these procedures with the use of cardiopulmonary bypass, repairing the congenital defect after lead extraction. After extraction, the left ventricle is monitored by transesophageal echocardiography, and all debris is removed through an incision in the aorta before bypass support is removed. The new pacemaker or ICD is implanted transatrially to avoid passing the lead through the junction of the superior vena cava and atrium.

Byrd’s experience is based on the management of 10 consecutive patients, most of whom had chronic leads and were symptomatic. Symptoms included transient ischemic attack and/or cerebrovascular accident, and vegetation was apparent in symptomatic patients. All but one patient had leads passing from right to left through an atrial septal defect. One patient had a lead that was implanted through the subclavian artery and passed retrograde through the aortic valve into the left ventricle. The procedure included establishing CPB, using cardioplegia to stop ventricular contraction, cross-clamping the aorta as needed, extracting the leads using conventional tools, debriding the chambers, repairing the septal defects, continuously observing the left atrium and ventricle by TEE, and carefully restarting the heart with protection from inadvertent ejection of embolic material. A new transatrial right-sided implantation was performed off bypass with the use of fluoroscopy and the conventional approach. With this technique, all leads were removed, the congenital defects repaired, and the new devices implanted without sequelae. Developing a safe technique that does not use an OHS procedure would be difficult.