Long-term performance of active-fixation pacing leads: a prospective study

BACKGROUND: Despite the increasingly widespread use of active-fixation leads, long-term clinical follow-up of pacing lead outcomes is lacking. The aim was to analyze pacing parameters over a 2-year follow-up. We performed a prospective observational study of consecutive new pacemaker implants using the 1488T St. Jude (100) and the Medtronic 5076 (100) active-fixation leads. Detailed analysis of pacing parameters was collected at implant, day 1, and 1, 3, 6, 12, 18, and 24 months. METHODS AND RESULTS: One hundred patients underwent implantation of 100 dual-chamber pacemakers. Initial pacing parameters in the ventricle were threshold 0.7 +/- 0.2 V, R wave 12.0 +/- 6.5 mV, and impedance 879 +/- 224 Omega. Threshold increased significantly from day 1 (0.7 +/- 0.2 V) to month 1 (0.9 +/- 0.6 V, P < 0.01) and remained stable over the long term. Four of the 100 patients had a threshold >2 V (mean 3.3 +/- 0.9 V) all between day 1 and month 3. For all patients, R wave remained stable, but impedance declined significantly from day 1 (879 +/- 184 Omega) to month 1 (677 +/- 122 Omega, P < 0.01). There were no ventricular lead complications. Initial pacing parameters in the atrium were threshold 0.9 +/- 0.3 V, P wave 3.3 +/- 2.4 mV, and impedance 606 +/- 144 Omega. Threshold remained stable over the long-term follow-up. One of 100 patients had a rise in threshold >2 V (2.2 V) between day 1 and month 1. No patients underwent lead repositioning. Sensing and impedance remained stable over the long term. Patient follow-up was completed in 94% (6 unrelated deaths). There was an 8% incidence of atrial fibrillation. CONCLUSION: Active-fixation leads are generally associated with stable long-term pacing parameters.     

Delayed pericarditis associated with an implantable cardioverter defibrillator implantation using an active-fixation atrial lead

A 57-year-old man with nonischemic dilated cardiomyopathy and ventricular tachycardia underwent routine dual chamber implantable cardioverter defibrillator (ICD) implantation. An active-fixation atrial lead was positioned at the lateral wall of the right atrium. He subsequently developed chronic severe pericarditis. Histopathological findings of the pericardium showed mechanical stimulus localized pericarditis. This case demonstrates that contact of the screw of the active-fixation atrial lead with the pericardium may be a possible mechanism for pericarditis after pacemaker/ICD implantation.     

A simpler solution to the old problem of frozen leads

Pacemaker generator replacement is usually a straightforward and simple procedure. However, it is occasionally complicated by entrapment of the lead in the header. Solutions to this problem have been described previously. We describe a simpler and safer technique to solve this old problem.     

Randomized comparison of J-shaped atrial leads with and without active fixation mechanism

BACKGROUND: In this prospective, randomized, controlled study, we compared the performance of J-shaped active fixation (AF) atrial leads with J-shaped passive fixation (PF) leads, over a 1-year follow-up period. METHODS: A total of 200 consecutive patients were prospectively randomized for implantation with a Medtronic 5568 AF lead model (n = 103; Minneapolis, MN, USA) versus a Medtronic 5592 PF model (n = 97), and all lead-related measurements and complications were recorded over one year. RESULTS: All leads were successfully implanted with a nonsignificant difference in crossover rate to the alternative lead due to failed implantation (1 in the AF and 4 in the PF group, P = NS). Fluoroscopy time during implantation procedure was significantly shorter in the PF group (2.1 +/- 3.6 vs 3.3 +/- 4.5 minute, P < 0.05). Pacing thresholds during implantation were significantly lower in patients with PF leads (0.7 +/- 0.3 V vs 0.9 +/- 0.3 V, P < 0.001) and this difference persisted at 1-year follow-up (0.8 +/- 0.6 V vs 1.3 +/- 0.9 V in PF and AF leads respectively, P < 0.05). Lead-related complications occurred in PF and AF with similar frequency (4% and 9% respectively, P = 0.2). However, pericardial complications occurred only in the AF group (6 cases, P = 0.01). Lead dislodgement was observed in only two cases-both in the PF group (P = 0.3). CONCLUSION: Both types of J-shaped atrial leads had reasonable performance. PF leads required shorter fluoroscopy time for implantation, demonstrated a better pacing threshold over a 1-year follow-up period and had no pericardial complications, while AF lead implantation was complicated by pericardial irritation and/or effusion in 6% cases (P = 0.01).     

Management of symptomatic inadvertently placed endocardial leads in the left ventricle

Background: There are limited data regarding the clinical care of inadvertently placed endocardial leads in the left ventricle (LV). We clarified the appropriate management within the context of our experience and published literature. Methods: Hospital charts dating from October 2008 to December 2010 were reviewed at a high‐volume cardiovascular tertiary referral center. Six patients were identified with inadvertently placed leads in the LV through an atrial septal defect. Results: Six patients (four males, two females) underwent LV lead removal, four through open surgical intervention and two percutaneously. Three (50%) patients presented with severe mitral regurgitation; one (16%) with a thromboembolic transient ischemic attack and two (33%) were asymptomatic. The mean age was 68.5 ± 8.48 years (55–78). Mean ejection fraction was 38.47 ± 11.1% (25%–50%). Four patients (66%) had a pacemaker and two (33%) had implantable cardioverter defibrillators. Comorbidities consisted of diabetes mellitus (50%), chronic renal failure (16%), severe chronic pulmonary hypertension (16%), and congestive heart failure (33%). Hypertension and coronary arterial disease were present in all patients. All patients had complete extraction or repositioning without intraoperative complications or mortality within 30 days. At 6‐month follow‐up, the patient with severe pulmonary hypertension died of pneumonia and the other five were alive and well. Conclusion: The avoidance and early recognition of inadvertently placed endocardial leads in the LV is imperative in order to avoid potentially serious sequelae and invasive interventions. Treatment usually consists of surgical extraction, although anticoagulation and percutaneous simple traction techniques are an option in certain scenarios. (PACE 2011; 34:1192–1200)     

A safe and simple method for management of frozen pacemaker leads

The traction of frozen leads from the generator header is difficult in some patients. This report describes the authors' experience with frozen leads in which the lead pins were removed by pushing with the tip of screwdriver from the hole created with a scalpel blade at the closed end of the generator header.     

Outcome of young patients with abandoned, nonfunctional endocardial leads

Background: Transvenous leads may fail and may be extracted or abandoned. There are no reports of the outcome of children with abandoned nonfunctional leads.
Methods: We evaluated retrospectively the outcome of these patients, in our population of pacemaker (PM) patients. Data are reported as median (range).
Results: In 18 patients (of 245, 7%) with endocardial pacing systems implanted at 4 (0.3–19) years of age (15 VVIR and 3 DDD PM), 19 leads (16 ventricular, 3 atrial) failed (abnormal threshold increase in seven leads; exit block in nine including three atrial leads; insulation break in three) after 10 (3–15) years, and were abandoned. At 13 (6–30) years of age, seven patients received VDD PM, seven VVIR, three DDD, and one patient an epicardial system. Median number of abandoned leads is one (two in two patients). Final cross-sectional area (CSA) of the implanted leads is eight (2–14) mm². All the procedures were successfully completed. Follow-up (FU) duration is 4 (1–10) years. All new leads are functioning normally. No tricuspid valve dysfunction or new venous occlusion occurred. Two cases of lead endocarditis occurred after 5 and 10 years of follow-up in patients with two ventricular leads. No specific risk factors for endocarditis were identified.
Conclusions: Abandonment of a nonfunctioning lead is a palliative procedure, technically feasible, with no short-term complication. Two patients experienced late endocarditis of the leads.     

Constrictive pericarditis complicating endovascular pacemaker implantation

A patient is described who has 6 months of progressive dyspnea and peripheral edema for 4 years following implantation of an endovascular pacemaker, which was complicated by a large hemorrhagic pericardial effusion. Evaluation was consistent with constrictive pericarditis, which is an extremely unusual complication of pacemaker implantation.     

Safe and effective placement of two bipolar silicone leads in the cephalic vein using a hydrophilic guidewire and a split introducer

The cephalic vein (CV) is preferable to the subclavian vein for implanting permanent pacing leads because of fewer complications. Unfortunately, this access is unusable in a substantial number of patients. This prospective study evaluates a technique to increase CV access for the placement of two silicone bipolar leads used in DDD pulse generator implants. A standard cephalic cutdown was performed under local anesthesia and a hydrophilic guidewire (HGW) threaded in the CV. The first (ventricular) bipolar lead was then introduced and positioned. When possible, introduction of the second (atrial) lead followed the same direct access. A failed introduction led to a modified procedure (MP) relying on a "split" introducer (8-9 Fr Plastimed) advanced with a circular motion over the HGW, then removal of the dilator, removal of the HGW, insertion of the pacing lead into the sheath with placement in the right atrium, followed by sheath withdrawal. Over an 18-month period, 90 consecutive patients had DDD pacemakers implanted. The CV was accessible in 76 (84.5%) of 90 patients and the direct introduction of the ventricular lead was obtained in 74 (97.4%) of these. Atrialization proceeded as follows: direct access CV in 14 (18%) of 76 patients, MP access in 54 (71%) of 76 patients, and MP failure in 8 (11%) of 76 patients. Overall, this approach allowed cephalic dual insertion in 68 (89%) of 76 patients. In conclusion, the modified procedure presented in this study allows a dual catheterization with bipolar leads in 89% of patients when a CV is available. This significantly improves the success rate for dual bipolar lead implants in this configuration.     

Multi-center clinical experience with a lumenless, catheter-delivered, bipolar, permanent pacemaker lead: implant safety and electrical performance

PURPOSE: Reduced lead diameter and reliability can be designed into transvenous permanent pacing leads through use of redundant insulation and removal of the stylet lumen. The model 3830 lead (Medtronic Inc., Minneapolis, MN, USA) is a bipolar, fixed-screw, steroid-eluting, lumenless, 4.1-Fr pacing lead. Implantation can be performed in a variety of right heart sites using a deflectable catheter (Model 10600, Medtronic). Lead performance and safety were studied. METHODS: Two prospective trials of 338 implanted subjects from 56 global sites were conducted. Electrical and safety data were obtained at implant, pre-discharge, and up to 18 months post-implant. Leads were implanted at traditional and alternate right heart sites. RESULTS: The study enrolled 338 subjects (204 males, 70.6 +/- 11.6 years) followed-up for a mean of 10.2 months (range, 0-21.6). Mean P-wave amplitudes ranged from 3.2 mV at 3 months to 2.9 mV at 18 months, while mean atrial pulse width thresholds at 2.5 V ranged from 0.07 ms at 3 months to 0.09 ms at 18 months. Mean R-wave amplitudes ranged from 11.3 mV to 11.1 mV and mean ventricular pulse width thresholds at 2.5 V ranged from 0.10 ms to 0.14 ms. There were 22 ventricular and 12 atrial lead complications within 3 months post-implant. Survival from lead-related complications improved to a clinically acceptable rate in the cohort of patients when revised implant techniques were employed. CONCLUSIONS: With the use of recommended implant techniques, the study results support the electrical efficacy and safety of a catheter-delivered, lumenless lead in traditional or alternate right atrium or right ventricle sites through 18 months post-implant.     

Upgrading of VVIR pacemakers with nonfunctional endocardial ventricular leads to VDD pacemakers in adolescents

Background: In some children with ventricular rate responsive demand (VVIR) pacemakers (PM), transvenous leads fail for technical reasons or patient's growth.
Aim: The aim of this study is to describe our experience in adolescents with a nonfunctional ventricular lead in whom the lead was abandoned and an additional VDD lead was implanted. Of the 136 children who received a VVIR PM with an endocardial lead in our center, seven patients aged 7 (0.3–12) years [median (range)] at initial implantation, after 10 (5–15) years showed lead malfunction and underwent atrial synchronous ventricular inhibited pacing (VDD) PM upgrading at 16 (10–20) years.
Results: The VDD lead was inserted through the ipsilateral subclavian vein in five patients, the contralateral in two (venous occlusion in one and for operator choice in the first patient). The tip was positioned into the right ventricular apex, the atrial dipole along the lateral atrial wall. Fluoroscopy times were not significantly different from those measured in SSI PM implantation and in VVIR dual-chamber demand pacing (VVIR-DDD) upgrading. There were no intraprocedural complications. Follow-up duration is 12 (6–62) months. The VDD PM showed good function, no undersensing or oversensing. Tricuspid damage, new venous occlusion, and "twisting" of the two leads at x-ray were not documented. The first patient showed an infection of the old PM pocket after 1 year, local pain after 3 years, and endocarditis of the leads after 5 years.
Conclusion: The upgrading of VVIR PM to VDD PM with the abandonment of the nonfunctional lead is feasible, with no intraprocedural complications and good PM function. Lead endocarditis occurred in one patient.     

High Rate of Late Dislodgements of an Active Fixation Atrial Lead

Between May 1985 and May 1991 we implanted 115 DFH-leads as unipolar atrial leads. The active fixation mechanism of this electrode consists of two sickle-shaped anchoring hooks which are placed at a distance of 0.9 mm parallel to the distal flat end of the electrode. All leads were affixed to the free wall of the right atrium. One hundred eight leads (93.9%) were implanted for dual chamber pacing and seven leads (6.1%) for single chamber atrial pacing. Parameters measured at implantation were (mean values): stimulation threshold 1.06 ± 0.42 V at 0.5 msec pulse width, P wave amplitude 5.12 ± 2.04 mV, and lead impedance 560 ± 76.1 Ohms. Within the first week after implantation, three early dislodgements occurred (2.6%). The follow-up period averaged 30.4 ± 16.2 months (range 2–76 months). During this time, 14 late macrodislodgements (12.2%) occurred after a mean period of 18.4 months (range 2–59 months). All of them required reoperation. The active fixation mechanism of the DEH-lead appears to be unreliable, if implanted in the free wall of the right atrium for dual chamber pacing.     

Steroid-Tipped Leads Versus Porous Platinum Permanent Pacemaker Leads: A Controlled Study

WISH, M., ET AL.: Steroid-Tipped Leads Versus Porous Platinum Permanent Pacemaker Leads: A Controlled Study. There is little data directly comparing steroid-tipped permanent pacemaker leads to otherwise state-of-the-art porous platinum leads. Eighteen patients receiving unipolar generators capable of low voltage outputs were randomized at the time of implant to receive either steroid-tipped leads or porous platinum leads. All leads were unipolar, tined, passive fixation, and placed in the right ventricular apex or atrial appendage. This study is single center. At implant, threshold pulse width was determined at 3 voltages (2.5, 1.5, and 0.8 V). Follow-up thresholds were determined at weeks 1, 2, 3, and 4, and at 3 and 6 months. There was no difference in implant thresholds or amplitudes for sensing. By 2 weeks postimplant, lower thresholds were noted for the steroid leads, and this discrepancy grew more significant with time. There was no significant postimplant rise in threshold for steroid-tipped leads. At 6 months, the average threshold pulse width for ventricular steroid leads at 0.8 V was 0.3 ± 0.1 msec. In contrast, five patients with standard leads did not capture at maximum pulse width at 0.8 V (p < 0.0001). There was no significant difference in the amplitude of the chronic atrial electrogram. This study shows steroid-tipped leads to offer a significant advantage in reducing thresholds early postimplant and chronically.     

Lead stuck (frozen) in header: salvage by bone cutter versus other techniques. jfisher@montefiore.org

It is occasionally difficult to disconnect leads from headers at the time of pulse generator replacement without injuring the fragile leads. Over a 2.5-year period we encountered this problem in six cases (1.7% of pulse generator replacements). The posterior portion of the header was clipped off using an orthopedic bone cutter in four cases. The cut was aligned with the deep end of the lead socket in the header. A metal rod was then used to push the lead out of the socket. Bench testing of alternative methods was done on previously explanted pulse generators that were firmly held in a vice. Motorized microtools were used to drill holes from the end of the header to the deep end of the socket; or with a rotary saw attachment to slice off the back of the header, allowing a retained lead to be pushed out. The latter was also done with a hand held razor saw, and attempts were made with a scalpel. Lead removal in the clinical cases was accomplished quickly in the four cases using the bone-cutter, without trauma to the lead. Bench testing results varied. The bone cutter was the most efficient method for most brands, but was ineffective on one. The motorized tool was difficult to position, produced sprays of plastic particles, and would have been risky in a clinical setting. The razor saw was difficult to use safely, or efficiently, except in some headers that resisted the bone cutter. The scalpel failed except in one "soft header" pacemaker. An orthopedic bone cutter is a useful tool for removing a retained lead from a pulse generator header. Different header designs and materials necessitate knowledge of several lead detachment methods.     

Incidence of complications in patients with implantable cardioverter/defibrillator who receive additional transvenous pace/sense leads

BACKGROUND: Implantation of an additional pace/sense (P/S) lead is commonly used in patients with implantable cardioverter/defibrillators (ICDs) to overcome P/S defects of integrated defibrillation leads (HV-P/S leads). No information is available about the clinical outcome and the incidence of complications in these patients. METHODS: Retrospective analysis was performed in 151 patients (125 male, age 54.9 +/- 13.6 years, LVEF 48.1 +/- 17.8%, CAD in 86 [57%], DCM in 24 [16%], ARVCM in 11 [7%]) who received an additional P/S lead between 1990 and 2002 (54 patients with abdominal and 97 patients with pectoral ICD system). Statistical analysis was done using Kaplan-Meier survival curves. RESULTS: The average follow-up (FU) after implantation of the additional P/S lead was 43 +/- 27 months. In total 117 patients [77.5%] remain implanted; 22 patients died due to cardiac-related reasons. After a FU of 23 +/- 23 months, 43 patients [28.5%] experienced lead-related problems after implantation of the additional P/S lead: oversensing in 23 [53.5%], insulation defect in 3 [7.0%], fracture in 1 [2.3%], system infection in 4 [9.3%], and defect of the HV-P/S lead in 6 [14.0%] patients. The event-free cumulative survival of the additional P/S lead after 1, 2, and 5 years was 87.0%, 79.8%, and 59.4%, respectively (for pectoral leads: 89.6%, 82.0%, and 60.0%, respectively). CONCLUSIONS: Implantation of an additional P/S lead in case of failure of an HV-P/S lead is safe. However, it is associated with a substantial rate of complications during FU. Therefore, extraction of damaged defibrillation leads instead of implantation of P/S leads should be favored.     

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.     

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.     

Current of injury predicts acute performance of catheter-delivered active fixation pacing leads

BACKGROUND: During pacemaker lead (PPML) implantation, the implanter must assess lead stability (fixation) and pacing threshold adequacy. Implanters rely principally on lead impedance (IMP) and pacing threshold measurements after fixation of the PPML to determine adequacy of pacing sites. Continuously monitoring lead parameters during fixation might better identify predictors of acute lead stability and performance. METHODS: At the time of PPML implantation with a catheter delivered, fixed screw, 4-Fr PPML (Medtronic 3830, Minneapolis, MN, USA) patients underwent measurements of R-wave amplitude, slew rate, and current of injury (COI) (maximum and at 80 ms) during each turn of the helix. Lead stability was tested with traction applied to the lead body. RESULTS: Eighteen patients (age 70 +/- 9 years, 9 males) were studied. Right ventricular lead positioning was attempted 43 times; 26 positions demonstrated good fixation and 18 had satisfactory threshold. Sites of good fixation consistently showed larger COI (maximum and at 80 ms) compared to poor fixation sites throughout each turn of the helix; R wave, slew rate, and IMP did not differ significantly. When all measures of COI were examined in a stepwise regression model only the final measure of COI at 80 ms proved significantly associated with acute stability (P = 0.032). CONCLUSIONS: Lead stability and threshold adequacy are predictable from assessment of the magnitude of injury current. Continuous monitoring of lead parameters during fixation does not appear to confer any benefit over assessment of the parameters after final rotation of the lead. A negative COI is associated with poor threshold and/or fixation.