Retained pacemaker leads

Adaptive conductive electrotherapeutic scaffolds for enhanced peripheral nerve regeneration and stimulation

BACKGROUND

While peripheral nerve stimulation (PNS) has shown promise in applications ranging from peripheral nerve regeneration to therapeutic organ stimulation, clinical implementation has been impeded by various technological limitations, including surgical placement, lead migration, and atraumatic removal.

METHODS

We describe the design and validation of a platform technology for nerve regeneration and interfacing: adaptive, conductive, and electrotherapeutic scaffolds (ACESs). ACESs are comprised of an alginate/poly-acrylamide interpenetrating network hydrogel optimized for both open surgical and minimally invasive percutaneous approaches.

FINDINGS

In a rodent model of sciatic nerve repair, ACESs significantly improved motor and sensory recovery (p < 0.05), increased muscle mass (p < 0.05), and increased axonogenesis (p < 0.05). Triggered dissolution of ACESs enabled atraumatic, percutaneous removal of leads at forces significantly lower than controls (p < 0.05). In a porcine model, ultrasound-guided percutaneous placement of leads with an injectable ACES near the femoral and cervical vagus nerves facilitated stimulus conduction at significantly greater lengths than saline controls (p < 0.05).

CONCLUSION

Overall, ACESs facilitated lead placement, stabilization, stimulation, and atraumatic removal, enabling therapeutic PNS as demonstrated in small- and large-animal models.

FUNDING

This work was supported by K. Lisa Yang Center for Bionics at MIT.

Frequency and clinical impact of retained implantable cardioverter defibrillator lead materials in heart transplant recipients

End-stage heart failure patients with implantable cardioverter-defibrillator (ICD) with/without cardiac resynchronization therapy (CRT-D) often require heart transplantation (HTPL) as a last-resort treatment. We aimed to assess the frequency and clinical impact of retained ICD lead materials in HTPL patients. In this retrospective single center study, we examined the clinical records and chest radiographs of patients with ICD and CRT-D who underwent HTPL between January 1992 and July 2014. Of 40 patients with ICD and CRT-D at HTPL, 19 (47.5%) patients had retained ICD lead materials within the central venous system. Retained ICD lead materials following HTPL were more frequently noted in patients with longer implantation durations until HTPL. None of the patients underwent extraction procedures after HTPL. All patients were asymptomatic and did not exhibit significant complications or death related to the retained ICD lead materials. Seven (7/40, 17.5%) patients without any retained ICD lead materials underwent magnetic resonance imaging (MRI) during the follow-up period (median, 29.5 months); none of the patients with retained lead materials were given MRI. Considering the common use of MRI in HTPL patients, further studies on the prophylactic extraction of retained ICD lead materials and safety of MRI in these patients are needed.

Cardiac Implantable Electronic Device Infections: Added Complexity and Suboptimal Outcomes With Previously Abandoned Leads

OBJECTIVES

This study sought to assess the impact of previously abandoned leads on the clinical management of cardiac device infections, notably transvenous lead extraction and subsequent clinical course.

BACKGROUND

The population of patients with cardiac implantable electronic devices continues to grow with a disproportionate increase in device infections, which are invariably life threatening. A potentially complicating issue is the widely practiced strategy of device lead abandonment at the time of system revision, change, or upgrade, which is affecting an increasing number of patients.

METHODS

The study assessed the impact of previously abandoned leads in a prospectively maintained registry of consecutive patients undergoing percutaneous extraction of infected cardiac devices at the Cleveland Clinic between August 1996 and September 2012. The primary clinical endpoint was complete procedural and clinical success defined as the successful removal of the device and all lead material from the vascular space, in the absence of a major complication.

RESULTS

Of 1,386 patients with infected cardiac devices, 323 (23.3%) had previously abandoned leads. Failure to achieve the primary endpoint occurred more frequently in patients with abandoned leads (13.0% vs. 3.7%; p < 0.0001). This was primarily due to retention of lead material (11.5% vs. 2.9%; p < 0.0001), which was associated with poor clinical outcomes including higher rates of 1-month mortality (7.4% vs. 3.5% in those without lead remnants). Lead extraction procedures in patients with previously abandoned leads were longer (p < 0.0001), with longer fluoroscopy times (p < 0.0001), and more likely to require specialized extraction tools (94.4% vs. 81.8%; p < 0.0001) or adjunctive rescue femoral workstations (14.9% vs. 2.9%; p < 0.0001). Procedural complications occurred more frequently in patients with previously abandoned leads (11.5% vs. 5.6%; p = 0.0003), which was true for both major (3.7% vs. 1.4%; p = 0.009) and minor complications (7.7% vs. 4.4%; p = 0.02).

CONCLUSIONS

Previously abandoned leads complicate the management of cardiac device infections, leading to worse clinical outcomes.

Extraction of cardiac rhythm devices: indications, techniques and outcomes for the removal of pacemaker and defibrillator leads

Cardiac rhythm management devices (pacemakers) are being increasingly implanted worldwide not only for symptomatic bradycardia, but also for the management of arrhythmia and heart failure. Their use in more elderly patients with significant comorbidities is rising steeply and consequently long-term complications are increasingly arising. Such an increase in device therapy is being paralleled by an increase in the requirement for system extraction. Safe lead extraction is central to the management of much of the complications related to pacemakers. The most common indication for lead extraction is system infection Adhesions in chronically implanted leads can become major obstacles to safe lead extraction and life-threatening bleeding and cardiac perforations may occur. Over the last 20 years, specific tools and techniques for transvenous lead extraction have been developed to assist in freeing the lead body from the adhesions. This article provides a comprehensive review of the indications, tools, techniques and outcomes for transvenous lead extraction. The success rate largely depends on the time from implant. Up to 12 months from implant, it is rare that traction alone will not suffice. For longer lead implant duration, no single technique is sufficient to address all extractions, but laser provides the best chance of extracting the entire lead. Operator experience is vital in determining success as familiarity of a wide array of techniques will increase the likelihood of uncomplicated extraction. Long implantation time, lack of operator experience, ICD lead type and female gender are risk factors for life-threatening complications. Lead extraction should therefore, ideally be performed in high volume centres with experienced staff and on-site support from a cardiothoracic surgical team able to deal with bleeding complications from cardiovascular perforation.

Transvenous removal of pacing and implantable cardiac defibrillating leads using single sheath mechanical dilatation and multiple venous approaches: high success rate and safety in more than 2000 leads

AIMS

The aim of the present study was to describe a 10 years single-centre experience in pacing and defibrillating leads removal using an effective and safe modified mechanical dilatation technique.

METHODS AND RESULTS

We developed a single mechanical dilating sheath extraction technique with multiple venous entry site approaches. We performed a venous entry site approach (VEA) in cases of exposed leads and an alternative transvenous femoral approach (TFA) combined with an internal transjugular approach (ITA) in the presence of very tight binding sites causing failure of VEA extraction or in cases of free-floating leads. We attempted to remove 2062 leads [1825 pacing and 237 implantable cardiac defibrillating (ICD) leads; 1989 exposed at the venous entry site and 73 free-floating] in 1193 consecutive patients. The VEA was effective in 1799 leads, the TFA in 28, and the ITA in 205; in the overall population, we completely removed 2032 leads (98.4%), partially removed 18 (0.9%), and failed to remove 12 leads (0.6%). Major complications were observed in eight patients (0.7%), causing three deaths (0.3%).

CONCLUSION

Mechanical single sheath extraction technique with multiple venous entry site approaches is effective, safe, and with a good cost effective profile for pacing and ICD leads removal.

Laser Lead Extraction: Predictors of Success and Complications

BACKGROUND

Paralleling the rise in pacemaker and defibrillator implantations, lead extraction procedures are increasingly required. Concerns regarding failure and complications remain.

METHODS AND RESULTS

A total of 200 lead extraction procedures were performed at the Montreal Heart Institute between September 2000 and August 2005. In 23 patients, all leads were removed by traction with a locking stylet. A total of 270 leads were extracted using a laser sheath system (Spectranectics, Colorado Springs, CO, USA) in 177 procedures involving 175 patients (74% male), age 62+/-16 years. Procedural indications were: infection 88 (50%), dysfunction 54 (30%), upgrade 21 (12%), and other 14 (8%). Overall, 241 leads (89%) were successfully extracted, 7 (3%) were partially extracted (< or = 4 cm retained), and 22 (8%) were non-extractable. In multivariate analyses, predictors of failed extraction were longer time from implant (OR 1.16 per year, P=0.0001) and history of hypertension (OR 5.2, P=0.0023). Acute complications occurred in 14 of 177 procedures (7.9%): 8 (4.5%) minor and 6 (3.4%) major, with one death. In multivariate analyses, the only predictor of acute complications was laser lead extraction from both right and left sides during the same procedure (OR 9.4, P = 0.0119). In addition, 3 of 10 patients with failed or partially extracted infected systems eventually required open chest explantation because of endocarditis.

CONCLUSION

Most leads not amenable to manual traction may be successfully extracted by a percutaneous laser sheath system. While most complications are minor, major complications including death may occur. Older leads are at higher risk for failed extraction. Endocarditis may ensue if infected leads are incompletely removed.

Right Ventricular and Tricuspid Valve Function in Patients With Two Ventricular Pacemaker Leads

Existing data on the effect of retained pacemaker leads on right ventricular (RV) and tricuspid valve function is limited.

OBJECTIVE

In this echocardiographic study we investigated the long-term effect of retained ventricular leads on RV and tricuspid valve function in patients with permanent pacemakers. Forty patients, 18 with two (group I) and 22 with one (group II) ventricular lead were assessed echocardiographically at an average of 39 months after the second lead implantation in group I and 80 months after the lead implantation in group II. The sum of the lead body diameter in group I was significantly greater than the body diameter in group II (P < 0.000). There was no significant difference between the groups with respect to chamber diameters and ventricular or valvular functions. The distributions of the different tricuspid regurgitation (TR) grades were similar, with the majority of patients in both groups having mild TR. Retained second pacemaker leads do not have an additional negative effect on right ventricular and tricuspid valve function.

Muscle stimulation related to a nonfunctioning epicardial pacemaker electrode

Noninfected retained pacemaker leads produce fewer complications than infected electrodes. Epicardial electrodes are rarely used, thus complications associated with such electrodes are seldom reported. We report a case with muscle stimulation due to a retained epicardial pacemaker electrode.

Long-term outcome of patients with multiple (> or = 3) noninfected transvenous leads: a clinical and echocardiographic study

To prospectively assess the incidence and clinical significance of thromboembolic complications in patients with multiple (> or = 3) noninfected transvenous leads; 48 consecutive patients were evaluated. Half of the patients had two ventricular leads and one atrial lead, 15 patients had two atrial leads and one ventricular lead, while 9 patients had two ventricular and two atrial leads. No additional care was provided except for aspirin (80 mg bid) and annually performed echo-Doppler studies. Clinical follow-up included signs and symptoms of subclavian and/or axillary vein thrombosis, the presence of right congestive heart failure, the number of hospital admissions, and death. Echo-Doppler studies assessed the presence of an enlarged right atrium or ventricle, right atrial or ventricular spontaneous contrast, and the presence of tricuspid regurgitation. During a total follow-up of 7.4 +/- 2.2 years there were no differences in the incidence of clinical variables as compared to age-matched controls with DDD pacemakers. The most common complication was transient venous thrombosis (mostly presenting as venous prominence 1-2 weeks after implantation), which was seen in 17% of the study group versus 15% in controls (NS). Cumulative mortality was not different in both groups (13% in the study group vs 15% in controls). No differences were present with respect to hospital admissions (1.1 +/- 0.27/year in the study group vs 1.2 +/- 0.30/year in the controls). In patients with multiple ventricular leads, tricuspid regurgitation on echo-Doppler studies was more frequent (24%) as compared to controls (4%); however, clinical signs of right heart failure were equally distributed. Thus, patients with multiple (> or = 3) noninfected leads have no clinical adverse outcome during long-term follow-up.

Intravascular extraction of problematic or infected permanent pacemaker leads: 1994-1996. U.S. Extraction Database, MED Institute

Of the 400,000-500,000 permanent pacemaker leads implanted worldwide each year, around 10% may eventually fail or become infected, becoming potential candidates for removal. Intravascular techniques for removing problematic or infected leads evolved over a 5-year period (1989-1993). This article analyzes results from January 1994 through April 1996, a period during which techniques were fairly stable. Extraction of 3,540 leads from 2,338 patients was attempted at 226 centers. Indications were: infection (27%), nonfunctional or incompatible leads (25%), Accufix or Encore leads (46%), or other causes (2%). Patients were 64+/-17 years of age (range 5-96); 59% were men, 41% women. Leads were implanted 47+/-41 months (maximum 26 years), in the atrium (53%), ventricle (46%), or SVC (1%). Extraction was attempted via the implant vein using locking stylets and dilator sheaths, and/or transfemorally using snares, retrieval baskets, and sheaths. Complete removal was achieved for 93% of leads, partial for 5%, and 2% were not removed. Risk of incomplete or failed extraction increased with implant duration (P<0.0001), less experienced physicians (P<0.0001), ventricular leads (P<0.005), noninfected patients (P<0.0005), and younger patients (P<0.0001). Major complications were reported for 1.4% of patients (<1% at centers with >300 cases), minor for 1.7%. Risk of complications increased with number of leads removed (P<0.005) and with less experienced physicians (P<0.005); risk of major complications was higher for women (P<0.01). Given physician experience, appropriate precautions, and appropriate patient selection, contemporary lead removal techniques allow success with low complication rates.

Percutaneous extraction of an abandoned coiled pacing lead

Abandoning redundant pacing leads has been an accepted practice in most cases. Late migration of a lead is a rare, unpredictable, and potentially lethal complication of this approach and requires immediate removal. We report the case of an atrial pacing lead that had migrated and was found coiled in the right atrium. It was removed by a snare catheter via a femoral approach.

Role of transesophageal echocardiography in the diagnosis of infected retained pacing lead

A 68-year-old woman had a transvenous pacemaker implanted 6 years ago. One year after the procedure the pulse generator was removed due to generator site infection. Efforts to remove the lead resulted in fracture of the tip, which was abandoned in the right cardiac cavities. After this the patient suffered intermittent episodes of fever and chills, which responded to antibiotic therapy. At her recent admission, transesophageal echocardiography revealed a large mass attached to the free end of the fractured lead suggestive of the existence of a vegetation on the pacing lead. The diagnosis was confirmed at surgery.

Venous access thrombosis detected by transcutaneous vascular ultrasound in patients with single-polyurethane-lead permanent pacemaker

In order to assess the incidence of significant venous thrombosis after transvenous permanent pacemaker implantation, transcutaneous ultrasound studies were performed in 109 consecutive patients with single-polyurethane-lead pacemakers. Ultrasonic evaluation was found to be a good noninvasive method in assessing the veins. Six patients (5.5%) were found to have significant venous obstruction in the subclavian vein. However, none of them were symptomatic. No difference in the incidence of venous obstruction was found, based on the age, duration of implantation, operative technique, potentially thrombogenic factors including atrial fibrillation, diabeties mellitus, hypertension, heart failure and end-stage renal disease.

The effect of nonisodiametric design on the ease of extracting chronically implanted pacemaker leads

Extracting permanently implanted transvenous pacemaker leads is often difficult because a fibrous sheath tends to trap the lead at various points along its course. Because many leads have bulbous or nonisodiametric portions, extraction may be rendered even more troublesome, because it is difficult to pull the larger portion through the narrow areas of the sheath. Furthermore, forceful extraction may have dire consequences, such as cardiac laceration. A study was undertaken in animals to evaluate the effect of lead isodiametricity on lead extraction. The results show that any increase in the diameter of the lead tip greatly reduces the ease of its removal. Consequently, leads designed to be isodiametric throughout their entire lengths will greatly enhance their removability.

Surgical management of infected permanent transvenous pacemaker systems: ten year experience

BACKGROUND

Between January 1985 and June 1995, more than 1800 consecutive patients underwent implantation of a new permanent cardiac pacemaker at our institution. Thirty-six patients (0.02%) had 45 reinterventions for infected pacemaker systems.

METHODS

in group A, 24 of 27 patients received simultaneous implantation of a new pacemaker. One had reimplantation of the same pacemaker in the same pocket, and two did not require reimplantation. The leads were retained in 19 (70%) of the patients. In group B, nine patients underwent cardiopulmonary bypass or "pursestring" surgery for removal of an infected pacemaker; a new epicardial pacemaker system was simultaneously implanted in seven patients.

RESULTS

Identification of an infectious agent failed in 17 patients (47%), and Staphylococci were found in 15 patients (42%). The time from pacemaker implantation to onset of infection ranged from 1 month to 11 years (mean 31 months; median 19 months) and the time from onset of infection to surgical treatment from 1 month to 7 years (mean 7 months; median 2 months). The mean follow-up time is 74 months (range, 1 month to 10 years; median 5 years). There were 9 reoperations in 3 patients (16%) of group A for recurrent infection of their retained leads ultimately necessitating the use of open cardiac surgery. There was no early death; six patients died late due to unrelated causes.

CONCLUSIONS

Complete removal of all pacemaker leads is recommended; open heart surgery with the use of cardiopulmonary bypass is indicated in selected cases and is effective and safe.

Lead extraction in young patients with and without congenital heart disease using the subclavian approach

Pacemaker lead removal using interlocking stylets and dilator sheaths has greatly reduced the need for major surgical intervention when lead extraction is required. Previous reports have shown the utility of this method in older patients, most of whom have anatomically normal hearts. The purpose of this study is to report the results of this technique in young patients with and without congenital heart disease. There were 13 patients (M:F = 7:6) aged 9-26 years (median 13). Congenital heart disease was present in 8 of 13 patients. A total of 17 leads required removal; they had been implanted for 54 +/- 24 months (range 19-94). Leads were removed from the left subclavian vein (13) or right subclavian vein (4) only. Seventeen of 18 leads were completely removed and one partially retained in the left subclavian vein. New leads were implanted from the same vein in 11 of 13 patients. Interlocking stylets and metal or flexible dilator sheaths were used in all cases except two. There was one surgical complication: a late wound dehiscence, which was easily managed. No patient required a transfusion, and there was no structural damage noted in any patient on the postoperative echocardiogram. We conclude that lead removal using interlocking stylets and dilator sheaths from the subclavian approach is an effective technique that can be used in young patients, including those with congenital heart disease.

Three-year experience with a stylet for lead extraction: a multicenter study

INTRODUCTION

The extraction of chronically implanted and infected pacemaker and defibrillator leads is an important issue. This article describes the experience gathered between 1990 and 1994 by seven European centers regarding a locking stylet that is uniformly applicable for a wide variety of internal pacing coil diameters. This interventional locking stylet for lead extraction has an outer diameter of 0.4 mm (0.016 inches). The stylet consists of a hollow shaft in which an inner traction wire is embedded. At the tip of the inner traction wire an anchoring mechanism, which can be opened by retraction, is applied. Removal attempts were made for 150 leads, 110 in ventricular and 40 in atrial positions.

RESULTS

Complete removal was possible in 122 cases (81%). Partial removal was possible in 18 cases (12%). Failure to remove the lead with the extraction stylet was experienced in 10 cases (7%). In seven patients, the leads were removed by cardiothoracic surgery; 3 defective leads were left in place. There were no serious complications associated with the procedure. None of the patients died.

CONCLUSION

The experience with this extraction stylet for lead removal has shown good results. Despite a low complication rate thus far, each case for lead removal should be judged on the individual basis of benefit-to-risk ratio.

Instantaneous lead entrapment: an unusual complication of nonthoracotomy implantation of an endocardial defibrillation lead

Nonthoracotomy implantation of implantable cardioverter defibrillators is performed with transvenous leads that are similar to pacemaker leads and are subject to the same potential problems. We report an unusual complication of lead placement in which an electrode immediately became entrapped in the superior rim of the tricuspid valve, resisting all efforts at removal.

The Dotter retriever and pigtail catheter: efficacy in extraction of chronic transvenous pacemaker leads

Several techniques exist for percutaneous extraction of chronic pacemaker leads. To establish the efficacy of the Dotter retriever and pigtail catheter, we reviewed the removal of 59 endocardial pacemaker leads in 42 patients (mean age 71 years). The mean duration of lead implantation was 44 months (range 1-169 months). Thirty-two leads were withdrawn with simple traction alone, and five leads were abandoned when traction failed. The remaining 22 leads were manipulated with a Dotter retriever or pigtail catheter, or both. Twelve leads were dislodged from the endocardium with simple traction (10) or with traction transmitted through an entwining pigtail catheter (2), but they could not be fully withdrawn. Eleven of these leads (92%) were then successfully extracted with the Dotter retriever. Seven of the remaining 10 leads were successfully dislodged and removed by the Dotter retriever. Overall, 9 of 12 leads (75%) that could not be dislodged from the endocardium with simple traction were removed with a Dotter retriever or pigtail catheter, or both. Three patients in whom no catheter method worked required thoracotomy for removal of infected leads. No complications resulted from use of the Dotter retriever or pigtail catheter. We conclude that the Dotter retriever and pigtail catheter have moderate efficacy for dislodging chronic endocardial leads. Once mobilized, however, the leads can be withdrawn with great success with the Dotter retriever. Newer technology should not result in the abandonment of this proven technique.

Intravascular extraction of chronic pacemaker leads: efficacy and follow-up

Extraction of chronic pacemaker leads has been recommended for infections, prevention of venous thrombosis, migration, and possible perforation. Success with constant traction techniques has been variable, and the cost and morbidity of open chest surgical procedures are prohibitive. Efficacy of a new system for lead extraction using intravascular techniques was analyzed. The system (Cook Pacemaker) uses a locking stylet, which is secured at the distal electrode by counterclockwise rotation to reinforce the lead and facilitate traction, and dilator sheaths that are used to free the lead from adhesions in the venous system. In a series of 56 patients (ages 19-88) who presented for lead extraction because of erosion (5), infection (14), lead replacement (35), or other (2), 86 leads were extracted. Thirty-two were atrial leads and 54 ventricular; 23 had active fixation and 63 passive. Average duration of implant was 58 +/- 42 months (range 1-264). Eighty-four leads were totally removed and two partially removed. For these two leads, the distal tip was not removed; in both cases the locking stylet was not secured at the distal electrode due to obstruction within the lead. Two patients developed arm edema following the procedure, which resolved with elevation. One patient developed a subclavian thrombosis, which resolved with warfarin anticoagulation. Four patients have expired due to unrelated causes. In conclusion, this intravascular approach for extraction of chronic leads is effective, and the procedure is safe when performed by experienced personnel.

Superior vena cava occlusion and/or syndrome related to pacemaker leads

Four cases of pacemaker-related SVC obstruction or syndrome are reported. While two of them lacked any symptom suggestive of SVC obstruction, the other two presented with mild symptoms. None of them received any treatment. One died from a cause unrelated to SVC obstruction, while the others presented no change in their clinical status. A review of the literature suggests that neither thrombotic nor fibrotic obstruction in patients with pacemaker leads is strictly related to the number of abandoned leads, the presence of severed leads, or the time elapsing from pacemaker implant. The diagnosis is clinically made and is confirmed by venography. Only one of the reported deaths is attributable to SVC obstruction. The remaining cases from the literature responded to treatment with heparin, thrombolytic agents, angioplasty, or surgery.

Infected endocardial pacemaker electrodes: successful open intracardiac removal

The long-term results after open intracardiac removal of infected pacing electrodes are presented.

METHODS

Between 1985 and 1990 open intracardiac removal of 19 infected pacing electrodes was performed in seven patients (six male and one female), with a mean age of 56 years. The indications were: persisting bacteremia in three; generator pocket infection in four; endocarditis in one; and ventricular tachycardia caused by retracted electrodes in one. All electrodes were fixed in the right heart and extraction by closed methods failed. Percutaneous catheter techniques were not applied in these seven patients. In five patients two ventricular electrodes had to be removed, and in two patients a single one. A total of seven atrial electrodes were removed in six patients (one electrode each in five patients; two electrodes in one patient). All atrial and two ventricular electrodes could be removed through a pursestring suture without use of a pump oxygenator. For the removal of ten ventricular electrodes in six patients (two electrodes each in four patients; 1 electrode each in two patients) a right-sided atriotomy was necessary with cardiopulmonary bypass (CPB). Simultaneously, five new pacing systems were implanted.

RESULTS

There were no early or late mortalities. In January 1991, all seven patients are alive and in a mean New York Heart Association Class 1,3 of heart failure after a mean interval of 33 months. In all cases the infection could controlled with a simultaneous antimicrobial chemotherapy and the postoperative period was free of major complications.

CONCLUSION

Open intracardiac removal of retained pacing electrodes with or without use of CPB is a safe procedure without major complications. It is mandatory for all infected pacing electrodes that cannot be extracted by closed methods.

Venous complications after insertion of a transvenous pacemaker

We reviewed the incidence, clinical features, current diagnostic evaluations, and treatments of venous complications that can occur after implantation of a transvenous pacemaker. Of the approximately 80 published articles on the potential venous complications after implantation of a permanent transvenous pacemaker, we selected 63 that addressed the clinical features, diagnosis, and treatment of pacemaker lead-induced venous thrombosis, which occurs in approximately 30 to 45% of patients early or late after implantation of a transvenous pacemaker. Most patients with chronic deep venous thrombosis remain asymptomatic because of the development of an adequate venous collateral circulation. Clinical features of pacemaker lead-induced deep venous thrombosis, although rare, are easily recognized. They should be sought routinely during follow-up of all patients with transvenous pacemaker leads because venous obstruction can interfere with intravenously administered therapy, monitoring of central venous pressure, and revision of a pacemaker lead. Acute deep venous thrombosis is likely to be symptomatic. Early recognition and treatment of acute deep venous thrombosis may help to decrease the potential morbidity and mortality. The definitive diagnosis of pacemaker lead-induced venous thrombosis necessitates contrast-enhanced or digital subtraction venography. Management includes anticoagulation, thrombolytic therapy, surgical intervention, and, recently, percutaneous transluminal balloon venoplasty and depends on the duration, extent, and site of venous occlusion as well as the accompanying symptoms.

Myocardial Rupture After Pulling Out a Tined Atrial Electrode with Continuous Traction

Transvenous traction for the removal of retained pacemaker electrodes is common practice with few reported complications. This case reports a patient with a DDD pacemaker with extruded electrodes, who died of a myocardial rupture at the atrial lead site after prolonged (i.e., after 24 hours) traction was applied.

Complications associated with retained pacemaker leads

Retention of functionless pacemaker leads may occur following mechanical or infective problems (potentially or definitely infected) or after electrical failure of the lead. One hundred nineteen patients with a pacemaker lead (or leads) retained between 1970 and 1990 were reviewed retrospectively. Lead retention after an intervention dictated by potential or definite infection of the pacing system resulted in complications in 27 of 53 patients (51%), which in 22 patients (42%) were major (septicemia, superior vena cava syndrome, and further surgery under general anesthesia for recurrent "infective" problems) including three deaths. Complications were less likely if lead retention occurred after electrical failure with three minor and two major (surgery under general anesthesia, superior vena cava syndrome) complications in 66 patients (P less than 0.001). Bacteriology of swabs taken at the time of retention in the patients with potential or definite infection was unhelpful in predicting future complications: 8/18 patients (44%) whose swabs were negative had complications of which 5/18 (28%) were major. In our experience retention of functionless pacemaker leads after an intervention dictated by potential or definite infection of the pacing system, is associated with significant morbidity and mortality and should be avoided.

Advances in pacing therapy for bradycardia

Advances have been made rapidly in the field of cardiac pacing. The most significant technologic advance is that of pacemakers capable of rate-adaptive pacing. Multiple types of sensors are now used for rate-adaptive pacing; some are commercially available and many are undergoing clinical investigation. In the near future, clinical investigation will begin on pacemakers that incorporate dual simultaneous sensors for rate-adaptive pacing. Significant improvement has been made in electrode design. Electrodes with low thresholds allow improved battery longevity. Steroid-eluting leads have proven reliable and capable of avoiding the early threshold rise seen with other electrodes. Standardization of pacemaker connector dimensions is now under way. The International Standards Organization has established the guidelines for connector standardization, and the guidelines have been adopted by the major manufacturers. The ultimate "smart" pacemaker would be capable of autoprogramming most or all of its programmable features. Many autoprogramming features have already been incorporated, and several others such as automatic programming of output and sensitivity are under investigation.

Extraction of implanted transvenous pacing leads: a review of a persistent clinical problem

Within a few months of implantation, permanent pacemaker leads become ensheathed in fibrocollagenous tissue. This tissue may anchor the lead so that it is difficult, dangerous, or impossible to remove it. Leads with bulbous or finned tips are particularly resistant to extraction. The risks of applying traction to an entrapped lead include induction of bradycardia or ventricular tachycardia and fibrillation, invagination of the right ventricle, avulsion of the right ventricular myocardium or tricuspid valve, hemopericardium, and cardiac tamponade. Forceful traction may result in uncoiling of the conductor, disruption of the insulation, or complete fracture, leaving an intravascular remnant that may embolize or be a source for thrombosis. Although fixation and abandonment of an inactive chronically implanted lead is frequently appropriate and is known to pose little long-term risk, the retained inactive lead may interact adversely with a new active lead and then increase the risk of venous thrombosis, serve as a potential nidus for infection, or produce spurious electrical sensing signals that may be sensed by the pulse generator. Absolute indications for lead removal are those in which there would be a life-threatening situation if the lead were to remain in situ. In the absence of an absolute indication, the decision to proceed with extraction must be made by weighing the potential for serious morbidity or mortality against risks of the extraction technique. Techniques for lead removal include traction and open cardiotomy operations. When a portion of the lead is intravascular, forceps, snares, baskets, countertraction, or lead-transection devices may be used to retrieve the fragment.

Chronic transvenous pacemaker lead removal using a unique, sequential transvenous system

Transvenous removal of 43 consecutive chronic pacemaker leads was successful in 28 patients. For leads not removed by traction at the pacemaker connection terminal, a unique locking stylet was advanced through the inner coil lumen and engaged at the tip to allow traction without lead elongation. Leads not extracted with the locking stylet alone had traction maintained on the stylet as sheaths were advanced over the lead to dilate and detach any fibrous tissue adherent to the lead. By applying traction at the pacemaker connection terminal, 2 leads were removed. The locking stylet alone extracted 9 leads. Both the locking stylet and sheaths were necessary to explant 32 leads. There were 15 right atrial and 22 right ventricular leads completely removed. Additionally, 6 right ventricular leads were subtotally removed leaving only the tip in the right ventricular apex. Avulsed myocardium was removed with the lead in 1 patient without sequelae. A subacute hemothorax developed in 1 patient 18 days after discharge requiring drainage, and subclavian vein thrombosis developed in another, which was successfully treated with anticoagulation. Hypotension occurred in 1 patient during final positioning of new leads, which responded to conservative treatment. Chronic pacemaker leads can be reliably removed without thoracotomy. Both a unique locking stylet to allow traction without lead elongation and a sheath to dilate and detach adherent fibrous tissue are needed for consistent success. Recognized complications included myocardial avulsion without sequelae, subacute hemothorax, subclavian vein thrombosis and transient hypotension.

Pacemaker-induced superior vena cava syndrome: report of four cases and review of the literature

Superior vena cava syndrome due to transvenous pacing leads is a rare event. We describe four cases. One occurred among 3,100 primary pacemaker insertions performed at our institution. In the other three cases the primary insertion had been performed elsewhere. Over 30 cases have been reported previously. Local infection, which preceded the development of superior vena cava syndrome in each of our four cases, and the presence of a severed retained lead, as in three of our cases, are important predisposing factors. There is no strong evidence that multiple lead insertion, if each lead remains intact, significantly increases the risk. The pathology at the site of obstruction includes thrombosis and in some cases fibrotic narrowing. Venous angiography is useful to show the site of obstruction, the extent of collateral circulation and to assess the response to treatment. Treatment should include removal of any infected pacemaker apparatus, anticoagulation and, if symptoms are of recent onset, thrombolytic therapy. Most patients improve but in those who do not angioplasty or surgical relief of the obstruction may be helpful.