Aortic perforation by active-fixation atrial pacing lead

This report describes perforation of the aorta related to the implantation of an active-fixation atrial pacing lead, a previously undocumented complication of pacemaker implantation. The complication was related to excessive tissue penetration by the screw at the tip of the lead or perforation of the lead body by the positioning stylet during manipulation whereupon the stylet traversed the atrial wall and aortic wall. Perforation of the aorta should be part of the differential diagnosis of cardiac tamponade after pacemaker implantation.     

Cardiac tamponade as complication of active-fixation atrial lead perforations: proposed mechanism and management algorithm

BACKGROUND: Cardiac tamponade is a rare complication after implantation of dual chamber pacemaker or defibrillator systems. Its pathophysiology and optimal management are not currently well established. METHODS: Three cases of cardiac tamponade following successful implantation of transvenous dual chamber pacemakers with active-fixation atrial leads were identified. RESULTS: All three patients with post-implant cardiac tamponade were suspected to have the same etiology of bleeding into the pericardial space. This was due to protrusion of the helix of the active-fixation atrial pacing lead through the atrial wall with subsequent abrasion of visceral pericardial layer and bleeding from the atrium through the perforation. In two patients, the perforation sites were visualized and repaired during open thoracotomy in the operating room. The third patient underwent lead repositioning under fluoroscopic guidance in the electrophysiology laboratory. CONCLUSION: Based on the reviewed cases, we describe the pathophysiology of, and recommend a safe conservative algorithm for, the management of cardiac tamponade after successful transvenous lead implantation. Percutaneous pericardiocentesis with placement of the pericardial drain followed by lead repositioning under fluoroscopic guidance with surgical backup appears to be safe and effective.     

Postpacemaker implant pericarditis: incidence and outcomes with active-fixation leads

Pericarditis has been noted as a potential complication of pacemaker implantation. This study evaluated the risk of developing pericarditis following pacemaker implantation with active-fixation atrial leads. Included were 1,021 consecutive patients (mean age 73.4+/-0.4 years, range 16-101 years; 45.2% women) undergoing new pacemaker system implantation between 1991 and 1999 who were reviewed for the complication of pericarditis. The incidence and outcomes of postimplantation pericarditis in patients receiving active-fixation atrial leads were compared to those not receiving these leads. Of 79 patients who received active-fixation atrial leads, 4 (5%) developed pericarditis postpacemaker implantation. Of 942 patients with passive-fixation atrial leads or no atrial lead (i.e., a ventricular lead only), none developed pericarditis postoperatively (P < 0.001). Of patients receiving active-fixation ventricular leads only (n = 97), none developed pericarditis. No complications were apparent at the time of implantation in patients who developed pericarditis. Pleuritic chest pain developed between 1 and 28 hours postoperatively. Three patients had pericardial rubs without clinical or echocardiographic evidence of tamponade. They were treated conservatively with acetylsalicylic acid or ibuprofen and their symptoms resolved without sequelae in 1-8 days. One patient (without pericardial rub) died due to cardiac tamponade on postoperative day 6. Postmortem examination revealed hemorrhagic pericarditis with no gross evidence of lead perforation. Pericarditis complicates pacemaker implantation in significantly more patients who receive active-fixation atrial leads. It may be precipitated byperforation of the atrial lead screw through the thin atrial wall. Patients developing postoperative pericarditis should befollowed closely due to the risk of cardiac tamponade.     

Right Ventricular Septal Pacing: The Success of Stylet-Driven Active-Fixation Leads

Background: The detrimental effects of right ventricular (RV) apical pacing on left ventricular function has driven interest in alternative pacing sites and in particular the mid RV septum and RV outflow tract (RVOT). RV septal lead positioning can be successfully achieved with a specifically shaped stylet and confirmed by the left anterior oblique (LAO) fluoroscopic projection. Such a projection is neither always used nor available during pacemaker implantation. The aim of this study was to evaluate how effective is the stylet-driven technique in septal lead placement guided only by posterior-anterior (PA) fluoroscopic view.
Methods: One hundred consecutive patients with an indication for single- or dual-chamber pacing were enrolled. RV septal lead positioning was attempted in the PA projection only and confirmed by the LAO projection at the end of the procedure.
Results: The RV lead position was septal in 90% of the patients. This included mid RV in 56 and RVOT in 34 patients. There were no significant differences in the mean stimulation threshold, R-wave sensing, and lead impedance between the two sites . In the RVOT, 97% (34/35) of leads were placed on the septum, whereas in the mid RV the value was 89% (56/63).
Conclusions: The study confirms that conventional active-fixation pacing leads can be successfully and safely deployed onto the RV septum using a purposely-shaped stylet guided only by the PA fluoroscopic projection. (PACE 2010; 49–53)     

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.     

Stent Dilation of Superior Vena Cava and Innominate Vein Obstructions Permits Transvenous Pacing Lead Implantation

The purpose of this study was to assess the feasibility of stent dilation of venous obstructions/occlusions to permit transvenous pacing lead implantation. Innominate vein or superior vena cava (SVC) obstruction may preclude the implantation of transvenous pacing leads. Patients with d-transposition of the great arteries, after a Mustard or Senning procedure, and children with previously placed transvenous pacing leads are at higher risk for this vascular complication. From May 1993 to January 1996, eight pediatric patients who underwent transvenous pacing lead implantation or replacement were found to have significant innominate vein or SVC obstruction or occlusion. Utilizing in-travascular stents, a combined interventional and electrophysiological approach was used to relieve the venous obstruction and to permit implantation of a new transvenous pacing lead. Two patients had complete SVC occlusion requiring puncture through the obstruction with a transseptal needle. Vessel recanalization was achieved with balloon dilation and stent implantation. The remaining six patients had severe venous obstruction with a mean minimum diameter of 3.1 ± 3.3 mm. The mean pressure gradient across the obstructed veins was 8.6 ± 7.3 mmHg. Following implantation of 15 Palmaz P308 stents in eight vessels, the mean diameter increased to 14.2 ± 1.9 mm and the mean pressure gradient across the stented vessels decreased to 1.0 ± 2.0 mmHg, A transvenous pacing lead was implanted successfully through the stent (s) immediately or 6–8 weeks later. Innominate vein and SVC obstruction can be safely and effectively relieved with intravascular stents and permit immediate or subsequent transvenous pacing lead implantation.     

The right ventricular outflow tract: a comparative study of septal, anterior wall, and free wall pacing

BACKGROUND: There is marked heterogeneity in right ventricular outflow tract (RVOT) pacemaker lead placement using conventional leads. As a result, we have sought to identify a reproducible way of placing a ventricular lead onto the RVOT septum. METHODS AND RESULTS: A major determinant is the shape of the stylet used to deliver the active-fixation lead. We compared stylet shapes and configurations in patients who initially had a ventricular lead placed onto the anterior or free wall of the RVOT and then had the lead repositioned onto the septum. All leads were loaded with a stylet fashioned with a distal primary curve to facilitate delivery of the lead to the pulmonary artery, then using a pullback technique the lead was retracted to the RVOT. All lead placements were confirmed by fluoroscopy and electrocardiography. Anterior or free wall placement was achieved by the stylet having either the standard curve or an added distal anterior angulation. In contrast, septal lead positioning was uniformly achieved by a distal posterior angulation of the curved stylet. This difference in tip shape was highly predictive for septal placement (P < 0.001). With septal pacing, a narrower QRS duration was noted, compared to anterior or free wall pacing (136 vs 155 ms, P < 0.001). All pacing parameters were within acceptable limits. CONCLUSION: Using appropriately shaped stylets, pacing leads can now be placed into specific positions within the RVOT and in particular septal pacing can be reliably and reproducibly achieved. This is an important step in the standardization of lead placement in the RVOT.     

Late Complications in Patients with Pectoral Defibrillator Implants with Transvenous Defibrillator Lead Systems: High Incidence of Insulation Breakdown

As the majority of ICDs with transvenous leads are now implanted in tbe pectoral region, complications associated with the technique are being identified. To determine the incidence of lead complications in patients with transvenous defibrillator leads and ICDs implanted in the pectoral region, 132 unselected consecutive patients with transvenous defibrillator leads had ICDs implanted in the pectoral region. Three lead systems were used:(1) lead system 1(45 patients) consisted of a transvenous pacing sensing lead and a superior vena cava coil with a submuscular patch used for defibrillation;(2) lead system 2(36 patients) utilized a CPI Endotak lead system: and(3) lead system 3(51 patients) utilized a Medtronic Transvene lead system. Patients were followed for 3–54 months(cumulative 2,269, mean 18 months). The average duration of follow-up with the three systems was 32, 12, and 11 months, respectively. At 30 months follow-up, all three lead systems had a low incidence of complications. However, there was a 13% overall incidence(45% actuarial incidence) of erosion of the insulation of the pacing sensing lead of system 1 at 50 months of follow-up. All lead complications were seen in patients with ICDs whose weights were > 195 g and volumes > 115 cc. The erosion was probably a consequence of the pressure by the large ICD against the lead in the pectoral pocket. Follow-up with lead systems 2 and 3 is relatively short(average 12 months) but no lead erosions were seen. Pectoral implantation of ICDs with long transvenous leads and large generators is associated with a moderate risk of late complications in the form of insulation breaks caused by pressure of the generator against the leads. The use of less redundant leads coupled with smaller ICDs will probably eliminate this complication.     

Effects of a Thin-Sized Lead Body of a Transvenous Single Coil Defibrillation Lead on ICD Implantation

SCHUCHERT, A., et al. : Effects of a Thin‐Sized Lead Body of a Transvenous Single Coil Defibrillation Lead on ICD Implantation. In the interest of patients receiving implantable cardioverter defibrillators (ICDs), the clinical benefits of newer and thinner transvenous defibrillation leads have to be determined. The aims of this study were to evaluate the ICD procedure duration and the frequency of lead dislocation at the 3‐month follow‐up of a new defibrillation lead with a thin‐sized lead body and its conventionalsized predecessor. The thin‐sized single coil defibrillation lead (Kainox RV, Biotronik; lead body 6.7 Fr) was implanted in 61 patients and the conventional‐sized defibrillation lead (SPS, Biotronik; lead body 7.8 Fr) in 60 patients. Both leads were connected to a left‐sided, prepectorally implanted Phylax ICD (Biotronik) with active housing. The lead implantation time and total procedure duration were determined. Lead implantation time was defined as the time from lead insertion to the end of the pacing measurements. The total procedure duration spanned skin incision to closure. The incidence of lead repositioning during the lead implantation time and during ventricular fibrillation conversion testing was also assessed. The frequency of lead dislocations was recorded at the 3‐month follow‐up. Mean lead implantation time and total procedure duration of the thin‐sized lead (23 ± 22 minutes 76 ± 37 minutes ) were not statistically different from the time needed for the conventional‐sized lead (22 ± 20 minutes 81 ± 34 minutes ). The number of lead repositionings during the lead implantation time was similar (thin‐sized lead: 1.4 ± 2.4 ; conventional‐sized lead: 1.1 ± 1.9 ). An additional lead repositioning was not necessary during ventricular fibrillation conversion testing in 93.4% of the patients with thin‐sized and in 94.4% with conventional‐sized leads (not significant). At the 3‐month follow‐up, there were four (6.6%) lead dislocations in the thin‐sized and four (6.7%) in the conventional‐sized lead group. In conclusion, the downsized lead body of the new defibrillation lead influenced neither ICD procedure duration nor the incidence of lead dislocation during follow‐up.     

Spurious Discharges Due to Late Insulation Break in Endocardial Sensing Leads for Cardioverter Defibrillators

Despite their similarity to permanent pacemaker leads, endocardial sensing leads for Cardioverter defibrillators have a relatively high failure rate. We describe four patients with endocardial rate sensing leads who developed inappropriate discharges 10–30 months after implantation due to small breaks in the lead insulation. This problem may become increasingly common as the number of Cardioverter defibrillator implants with transvenous leads continues to grow and should be considered in the differential diagnosis of late sensing failure or inappropriate device discharges.     

Effectiveness of excimer laser-assisted pacing and ICD lead extraction in children and young adults

BACKGROUND: High capture thresholds, decreased electrical sensing, and lead fractures continue to be a problem in children undergoing transvenous pacing. The clinician must therefore decide at the time of pacing system revision to either abandon chronically implanted transvenous pacing leads or extract them. METHODS: We report our experience using an excimer laser-assisted (LA) strategy for removing chronically implanted pacing (36) and implantable cardioverter/defibrillator (ICD) (7) leads in children and young adults. The study population consisted of 25 patients, in whom 29 procedures were performed. The patients ranged in age from 8.4 to 39.9 years, median age was 13.9 years, at the time of the extraction procedure. In all procedures, a Spectranectics locking stylet and excimer laser sheath were used to assist in lead extraction. RESULTS: Lead removal was complete for 39 (91%) leads, and partial for four leads. In two patients, the pacing lead tip was retained and in two, the ring electrode from a bipolar pacing lead was left in situ. All ICD leads were removed completely. Two major complications occurred--cardiac perforation and tamponade (1), and thrombosis of the left subclavian/innominate vein (1). LA extraction facilitated the implantation of new pacing or ICD leads in three patients with obstructed venous access. CONCLUSIONS: Removal of pacing and ICD leads using an excimer LA technique was highly successful. Lead removal was complete in 91%. The most common indication for lead removal in our study was lead fracture. Complications were few, but may be significant.     

Malfunction of a Sheath-Retracting Active-Fixation Pacemaker Electrode Due to Impacted Endocardium

A patient is described in whom a sheath-retracting active-fixation pacemaker electrode dislodged shortly after successful transvenous implantation in the right atrial appendage. Attempts to reposition the lead were unsuccessful. Examination of the explanted electrode disclosed that inability to reposition the electrode was due to the fact that impacted tissue around the electrode "screw" prevented its being re-advanced out of its polyurethane housing. (PACE, Vol. 5, March-April, 1982)     

Cardiac pacing: memories of a bygone era

The first cardiac pacemaker implants occurred in the late 1950s and involved insertion of epicardial or epimyocardial leads and abdominal pulse generators. By the mid 1960s, cardiologists were making attempts to insert transvenous leads into the right ventricle. These early unipolar leads had large, polished, high polarization electrodes, no fixation device, and no lumen in which to place a stylet for lead positioning. The lead implantation procedures were usually long and the irradiation to both patient and operator excessive. Pulse generators were powered by zinc-mercury cells, which were large, unreliable, and prone to sudden output failure. Postoperative complications such as lead dislodgement, exit block, and premature power source failure were very common with most patients requiring further surgery within a year. Little has been written of this period and in particular the experiences of the operators, such that today's pacemaker implanters have virtually no knowledge of this bygone era. This historical report by four Australian cardiologists details the operative procedures and follow-up management of those original pacemaker recipients.     

Right ventricular outflow tract placement of defibrillation leads: five year experience

Over a 5-year period, 112 patients (89 male/23 female, mean age 65 years) underwent right ventricular outflow tract (RVOT) placement of permanent active-fixation transvenous pacing/defibrillating leads. At implantation, the pacing threshold was 0.6 +/- 0.3 V at 0.5 ms pulse duration and R wave amplitude was 10.9 +/- 4.9 mV. The defibrillation threshold (DFT) of right-sided implants was 17.7 +/- 3.4 J while that of left-sided implants was 16.1 +/- 3.3 J. Patients were followed at 1 and 3 month postimplant and at six-month intervals thereafter. At mean follow-up of 22.5 +/- 17.5 months (range 1-47 months) there were no lead dislodgments, unsuccessful shock therapies, or failure to sense or pace for bradycardia or tachycardia. Death was not sudden in the 17 patients who died. We conclude that RVOT pacing-defibrillation lead implantation is safe, efficacious, and potentially attractive because preliminary evidence suggests that it may not be associated with the adverse hemodynamic effects of pacing at the right ventricular apex.     

The world survey of cardiac pacing and cardioverter defibrillators: calendar year 2001

A worldwide cardiac pacing and ICD survey was undertaken for calendar year 2001. Fifty countries, 22 from Europe, 16 from the Asia Pacific region, 3 from the Middle East and Africa, and 9 from the Americas contributed to the survey. The United States had by far the largest number of cardiac pacemaker implants, although Germany had the highest new implants per million population. Virtually all countries that participated in the 1997 survey showed significant increases in implant numbers over the 4 years. High degree atrioventricular block and sick sinus syndrome remain the major indications for implantation of a cardiac pacemaker with < 2% biventricular pacing in those countries that implanted such systems in 2001. There remains a high percentage of VVIR pacing in the developing countries with only a few countries using substantial numbers of single lead VDD and AAIR systems. There has been an increase in the use of DDDR systems in most countries since the 1997 survey. Pacing leads were predominantly transvenous, bipolar, and passive fixation. There was an increased use of active-fixation leads in the atrium. There was a significant rise in the use of ICDs with the largest usage occurring in the United States. A group of enthusiastic survey coordinators has now been established. Recruitment of new countries will hopefully continue to obtain a fully global experience of cardiac pacing and ICD usage.     

Long-Term Thrombosis after Transvenous Permanent Pacemaker Implantation

To assess the efficacy of prophylactic administration of anticoagulant and antiaggregant drugs to prevent venous thrombosis after long-term transvenous permanent pacemaker implantation, venograms were performed in 100 consecutive patients at the elective replacement of the pacemaker. Mean follow-up period after initial transvenous permanent pacemaker implantation was 6.0 years. The venograms demonstrated normal in 77 patients. The remaining 23 venograms showed venous stenosis in 11 patients and total obstruction in 12 patients. Twenty-one of these 23 patients had venous collateral circulation. No difference was found in the incidence of venous abnormalities according to the route of entry, the lead insulation, the total number of the implanted leads, and anticoagulant and antiaggregant drugs. All these patients have remained asymptomatic. In conclusion, the incidence of venous thrombosis after long-term transvenous pacing is 23% and the causes of venous thrombosis may be endothelial trauma and underlying venous stenosis. As this article describes a retrospective limited study, we cannot find the efficacy of prophylactic administration of anticoagulant and antiaggregant drugs to prevent venous thrombosis formation after transvenous permanent pacemaker implantation. Further prospective study will be needed to assess the efficacy of prophylactic administration of anticoagulant and antiaggregant drugs.     

Perforation of the Right Ventricle by Transvenous Defibrillator Leads: Prevention and Treatment

A series of 78 consecutive implants of the transvene PCD (Medtronic, Inc.) defibrillator system is presented and the occurrence of right ventricular perforation in 4 patients reported (5.2%). Diagnosis of perforation is made using four signs: (1) decrease in arterial blood pressure without any other explanation; (2) decrease in pulsatility of the cardiac silhouette as monitored by fluoroscopy; (3) increased size of the cardiac silhouette; and (4) abnormal position of the transvenous lead too far out toward the left ventricle along the pericardial outline. Perforation causes rapid and dramatic cardiac tamponade due to the large diameter and stiffness of the coil carrier lead. Immediate drainage of the hemopericardium must be carried out using the transxiphoid approach. The use of a thin blue-coded lead stylet (0.014-inch gauge) is recommended over the stiffer maroon-coded stylet. Since treatment must be carried out immediately, it is advised that a surgeon either perform, assist, or be immediately available whenever one of these systems is implanted.     

ICD Leads:

GRADAUS, R., et al .: ICD Leads: Design and Chronic Dysfunctions. The treatment of ventricular tachyarrhythmias has changed over the last 10 years. Implantable cardioverter defibrillators (ICDs), once used only as a last resort therapy, have now become the treatment of choice. This change occurred before the first results of randomized studies on ICD therapy in patients with life-threatening ventricular tachyarrhythmias were published by the end of 1997. Technological advances of ICD therapy, in particular the development of transvenous leads, were to a large extent responsible for this change. Modern leads are characterized by their multilumen design that incorporates straight wires and coiled conductors into a single electrode body. Conductors and insulation are sheathed with additional insulation layers. The most frequently used insulating materials are silicone, polyurethane, and fluoropolymers. Lead failures are an important complication of ICD therapy. Fractured conductors, compression, creeping, or insulation defects from abrasion can cause such lead dysfunctions. Chronically implanted leads will inevitably have an increased risk of failure due to defects despite all technological advances. In the light of improving survival figures in patients with ventricular tachyarrhythmias and increasing numbers of ICD implantations, lead failures are becoming a clinical problem of ever increasing importance. Therefore, the question of which lead types necessitate extraction when a certain failure occurs and which leads can be left in place. Despite continuous improvements in lead extraction systems and growing experience in their use, the extraction of any pacemaker or ICD lead is associated with some risk of complications. (PACE 2003; 26[Pt. I]:649–657)     

Removal of Endocardial Defibrillation Leads

Two patients, each with an endocardial defibrillation lead system (Endotak O62), required lead removal; one because of chronic lead infection and the second because of spurious shocks caused by lead insulation damage. Neither lead could be removed by simple traction. The defective lead was removed by a combination of catheterization techniques including a steerable ablation catheter and traction, both under general anesthesia. The lead with the insulation defect was rapidly removed with a locking stylet, suggesting that endocardial lead defibrillating leads can be removed similarly to pacemaker leads, thus avoid thoracotomy.     

An Efficient Technique for Implantation of Atrial Leads from the Left Side

Implantation of an endocardial lead into the right atrial appendage is itself a simple procedure but may offer complexity if the lead is introduced from the left side of the body. Experimentation on eight corpses allowed determination of an efficient method of rapid and reliable implantation of a lead using an S-shaped stylet. The method has been used successfully in 65 clinical instances.