Evaluation and extraction of the Accufix atrial J lead

Late perforation by cardiac implantable electronic device leads: clinical presentation, diagnostic clues, and management

Late intracardiac lead perforation is defined as migration and perforation of an implanted lead after 1 month of cardiac electronic device implantation. It is an under-recognized complication with significant morbidity and mortality, particularly if not recognized early. Two patients with late perforation caused by passive-fixation leads are reported and the clinical features of their presentation and management are reviewed. We conducted a thorough review of the available English language literature pertaining to this complication to draw relevant conclusions regarding presentation, diagnosis, and management. Early recognition of this complication is important as the indications for and numbers of patients who receive cardiac implantable electronic devices continue to expand.

In vivo finite element model-based image analysis of pacemaker lead mechanics

BACKGROUND

Fractures of implanted pacemaker leads are currently identified by inspecting radiographic images without making full use of a priori known material and structural information. Moreover, lead designers are unable to incorporate clinical image data into analyses of lead mechanics.

METHODS

A novel finite element/active contour method was developed to quantify the in vivo mechanics of implanted leads by estimating the distributions of stress, strain, and traction using biplane videoradiographic images. The nonlinear equilibrium equations governing a thin elastic beam undergoing 3-D large rotation were solved using one-dimensional isoparametric finite elements. External forces based on local image greyscale values were computed from each pair of images using a perspective transformation governing the relationship between the image planes.

RESULTS

Cantilever beam forward solution results were within 0.2% of the analytic solution for a wide range of applied loads. The finite element/active contour model was able to reproduce the principal curvatures of a synthetic helix within 3% of the analytic solution and estimates of the helix's geometric torsion were within 20% of the analytic solution. Applying the method to biplane videoradiographic images of a lead acutely implanted in an anesthetized dog resulted in expected variations in curvature and bending stress between compliant and rigid segments of the lead.

CONCLUSIONS

By incorporating knowledge about lead geometric and material properties, the 3-D finite element/active contour method regularizes the image reconstruction problem and allows for more quantitative and automatic assessment of implanted lead mechanics.

Risks of spontaneous injury and extraction of an active fixation pacemaker lead: report of the Accufix Multicenter Clinical Study and Worldwide Registry

BACKGROUND

The Telectronics Accufix pacing leads were recalled in November 1994 after 2 deaths and 2 nonfatal injuries were reported. This multicenter clinical study (MCS) of patients with Accufix leads was designed to determine the rate of spontaneous injury related to the J retention wire and results of lead extraction.

METHODS AND RESULTS

The MCS included 2589 patients with Accufix atrial pacing leads that were implanted at or who were followed up at 12 medical centers. Patients underwent cinefluoroscopic imaging of their lead every 6 months. The risk of J retention wire fracture was approximately 5.6%/y at 5 years and 4.7%/y at 10 years after implantation. The annual risk of protrusion was 1.5%. A total of 40 spontaneous injuries were reported to a worldwide registry (WWR) that included data from 34 672 patients (34 892 Accufix leads), including pericardial tamponade (n=19), pericardial effusion (n=5), atrial perforation (n=3), J retention wire embolization (n=4), and death (n=6). The risk of injury was 0.02%/y (95% CI, 0.0025 to 0. 072) in the MCS and 0.048%/y (95% CI, 0.035 to 0.067) in the WWR. A total of 5299 leads (13%) have been extracted worldwide. After recall in the WWR, fatal extraction complications occurred in 0.4% of intravascular procedures (16 of 4023), with life-threatening complications in 0.5% (n=21). Extraction complications increased with implant duration, female sex, and J retention wire protrusion.

CONCLUSIONS

Accufix pacing leads pose a low, ongoing risk of injury. Extraction is associated with substantially higher risks, and a conservative management approach is indicated for most patients.

Extraction of pacemaker and implantable cardioverter defibrillator leads

The common reasons for removal of pacing and defibrillator leads are infection, malfunction, or design defects such as fracture of J wires in Teletronics Accufix leads (Telectronics Pacing, Englewood, CO), which impose considerable risk for cardiac morbidity and mortality. Chronically implanted leads are fixed to the myocardium by fibrous tissue. Fibrous scar tissue may also encase the lead along its course. Furthermore, fragility of the lead and its tendency to break when extraction force is applied to overcome resistance imparted by the scar tissue add to the challenge of lead extraction. Thus, the extraction of chronically implanted leads is an important issue. Until a few years ago, the only methods available for the removal of chronically implanted leads were traction on the proximal segment of the lead and cardiac surgery. New techniques were developed to extract the leads by a transvenous approach using locking stylets, sheaths, snares, and retrieval baskets. Lead extraction using intravascular countertraction methods has since evolved as a specialty of its own. Progress has also been made in developing other system, such as Excimer laser energy for lead extraction. In this article, we discuss principles, techniques, and experience with these methods of extraction of chronic pacemaker and defibrillator leads.

Migration and right atrial perforation of an Accufix atrial lead retention wire following partial lead removal during myomectomy

A 36-year-old man with a history of hypertrophic obstructive cardiomyopathy presented to the emergency room with "stabbing" chest pain. He had undergone dual-chamber pacemaker implantation in 1993 using an atrial lead (Accufix; Telectronics; Englewood, Colo) and a myomectomy in 1996 during which the distal portion of the atrial lead was removed. Digital fluoroscopy revealed that the retention wire had migrated out of the remaining atrial lead and perforated the right atrium. The retention wire was successfully removed percutaneously. The need for complete removal of the retention wire in the Accufix lead at the time of open-heart surgery is emphasized.

Cost comparison of radiofrequency modification and ablation of the atrioventricular junction in patients with chronic atrial fibrillation

BACKGROUND

Because it is not clear which technique is less expensive, the purpose of this study was to compare the cost of radiofrequency modification and ablation of the atrioventricular (AV) node in drug-refractory patients with atrial fibrillation and an uncontrolled ventricular rate.

METHODS AND RESULTS

The initial nominal charges for a successful procedure were compared in 10 patients with chronic atrial fibrillation who underwent modification of the AV node ($13 109+/-2002) and 14 similar patients who underwent ablation and pacemaker implantation ($28 302+/-2023, P<.001). On the basis of the long-term follow-up of patients who underwent each procedure, it was assumed that 31% of patients selected for the modification procedure would require a permanent pacemaker for inadvertent AV block or because of AV nodal ablation after a failed modification procedure and that the recurrence rate after AV node ablation would be 2%. The annual charges during follow-up were predicted and adjusted for recurrences and the need for additional procedures. The adjusted total charges at 1 year of follow-up were significantly lower for the modification procedure ($19 389+/-2002) than for the ablation procedure ($28 485+/-2023, P<.001). After 10 years of follow-up, the cumulative, adjusted charges for modification were $20 016 (42%) less than for ablation.

CONCLUSIONS

The initial charges generated by AV node modification are significantly lower than for AV node ablation in patients with chronic atrial fibrillation. Even when adjusted for higher failure and recurrence rates, the modification procedure retains a major cost advantage over ablation during long-term follow-up.

Teletronics 330-801 atrial lead extraction via the subclavian approach

BACKGROUND

The Telectronics 330-801 atrial J (801) lead was recalled after reports implicated lead fracture/retention wire protrusion in patient mortality and morbidity. Recent reports suggest that 801 lead extraction may be associated with substantial morbidity and, possibly, excess mortality. We hypothesized that the 801 lead could be extracted using the subclavian approach with a high success rate and acceptable morbidity.

METHODS

We analyzed the clinical outcomes in 60 consecutive patients who underwent 801 lead extraction.

RESULTS

Sixty patients (34 women) with a mean age of 67 +/- 14.8 years had 18 class I, 13 class II, and 29 class III fractures. The lead age was 39 +/- 17 months. The subclavian approach was successful in 58 of 60 patients (96%). Complications, three major and eight minor, occurred in 10 of 60 patients (16%). All complications were successfully treated. There were no deaths. Only concurrent ventricular lead extraction was associated with complications (p = 0.008 by Fisher's exact test).

CONCLUSIONS

Telectronics 801 leads can be successfully extracted using the subclavian approach with acceptable short-term morbidity, low mortality, and excellent long-term results.

Management of distal electrode detachment during lead extraction

A telectronics 330-801 atrial active fixation lead with multiple J retention wire fractures was extracted. Separation of the distal electrode occurred due to antecedent inner conductor fracture between the endocardial electrode pair. Techniques for removal of the free distal electrode are described, including use of biopsy forceps and a snare.