Deaths and cardiovascular injuries due to device-assisted implantable cardioverter-defibrillator and pacemaker lead extraction

Assessing the Reproducibility of Research Based on the Food and Drug Administration Manufacturer and User Facility Device Experience Data

OBJECTIVE

This article aims to assess the reproducibility of Manufacturer and User Facility Device Experience (MAUDE) data-driven studies by analyzing the data queries used in their research processes.

METHODS

Studies using MAUDE data were sourced from PubMed by searching for "MAUDE" or "Manufacturer and User Facility Device Experience" in titles or abstracts. We manually chose articles with executable queries. The reproducibility of each query was assessed by replicating it in the MAUDE Application Programming Interface. The reproducibility of a query is determined by a reproducibility coefficient that ranges from 0.95 to 1.05. This coefficient is calculated by comparing the number of medical device reports (MDRs) returned by the reproduced queries to the number of reported MDRs in the original studies. We also computed the reproducibility ratio, which is the fraction of reproducible queries in subgroups divided by the query complexity, the device category, and the presence of a data processing flow.

RESULTS

As of August 8, 2022, we identified 523 articles from which 336 contained queries, and 60 of these were executable. Among these, 14 queries were reproducible. Queries using a single field like product code, product class, or brand name showed higher reproducibility (50%, 33.3%, 31.3%) compared with other fields (8.3%, P = 0.037). Single-category device queries exhibited a higher reproducibility ratio than multicategory ones, but without statistical significance (27.1% versus 8.3%, P = 0.321). Studies including a data processing flow had a higher reproducibility ratio than those without, although this difference was not statistically significant (42.9% versus 17.4%, P = 0.107).

CONCLUSIONS

Our findings indicate that the reproducibility of queries in MAUDE data-driven studies is limited. Enhancing this requires the development of more effective MAUDE data query strategies and improved application programming interfaces.

Analysis of 1051 ICD Leads Extractions in Search of Factors Affecting Procedure Difficulty and Complications: Number of Coils, Tip Fixation and Position-Does It Matter?

Background: Implantable cardioverter-defibrillator (ICD) leads are considered a risk factor for major complications (MC) during transvenous lead extraction (TLE). Methods: We analyzed 3878 TLE procedures (including 1051 ICD lead extractions). Results: In patients with ICD lead removal, implant duration was almost half as long (69.69 vs. 114.0 months; p < 0.001), procedure complexity (duration of dilatation of all extracted leads, use of more advanced tools or additional venous access) (15.13% vs. 20.78%; p < 0.001) and MC (0.67% vs. 2.62%; p < 0.001) were significantly lower as compared to patients with pacing lead extraction. The procedural success rate was higher in these patients (98.29% vs. 94.04%; p < 0.001). Extraction of two or more ICD leads or additional superior vena cava (SVC) coil significantly prolonged procedure time, increased procedure complexity and use of auxiliary or advanced tools but did not influence the rate of MC. The type of ICD lead fixation and tip position did not affect TLE complexity, complications and clinical success although passive fixation reduces the likelihood of procedural success (OR = 0.297; p = 0.011). Multivariable regression analysis showed that ICD lead implant duration ≥120 months (OR = 2.956; p < 0.001) and the number of coils in targeted ICD lead(s) (OR = 2.123; p = 0.003) but not passive-fixation ICD leads (1.361; p = 0.149) or single coil ICD leads (OR = 1.540; p = 0.177) were predictors of higher procedure complexity, but had no influence on MC or clinical and procedural success. ICD lead implant duration was of crucial importance, similar to the number of leads. Lead dwell time >10 years is associated with a high level of procedure difficulty and complexity but not with MC and procedure-related deaths. Conclusions: The main factors affecting the transvenous removal of ICD leads are implant duration and the number of targeted ICD leads. Dual coil and passive fixation ICD leads are a bit more difficult to extract whereas fixation mechanism and tip position play a much less dominant role.

Soft, bioresorbable, transparent microelectrode arrays for multimodal spatiotemporal mapping and modulation of cardiac physiology

Transparent microelectrode arrays (MEAs) that allow multimodal investigation of the spatiotemporal cardiac characteristics are important in studying and treating heart disease. Existing implantable devices, however, are designed to support chronic operational lifetimes and require surgical extraction when they malfunction or are no longer needed. Meanwhile, bioresorbable systems that can self-eliminate after performing temporary functions are increasingly attractive because they avoid the costs/risks of surgical extraction. We report the design, fabrication, characterization, and validation of a soft, fully bioresorbable, and transparent MEA platform for bidirectional cardiac interfacing over a clinically relevant period. The MEA provides multiparametric electrical/optical mapping of cardiac dynamics and on-demand site-specific pacing to investigate and treat cardiac dysfunctions in rat and human heart models. The bioresorption dynamics and biocompatibility are investigated. The device designs serve as the basis for bioresorbable cardiac technologies for potential postsurgical monitoring and treating temporary patient pathological conditions in certain clinical scenarios, such as myocardial infarction, ischemia, and transcatheter aortic valve replacement.

Transvenous Lead Extraction: Work in Progress

Cardiac implantable electronic devices are the cornerstone of cardiac rhythm management, with a significant number of implantations annually. A rising prevalence of cardiac implantable electronic devices coupled with widening indications for device removal has fuelled a demand for transvenous lead extraction (TLE). With advancement of tools and techniques, the safety and efficacy profile of TLE has significantly improved since its inception. Despite these advances, TLE continues to carry risk of significant complications, including a superior vena cava injury and mortality. However, innovative approaches to lead extraction, including the use of the jugular and femoral accesses, offers potential for further gains in safety and efficacy. In this review, the indications and risks of TLE are discussed while examining the evolution of this procedure from simple traction to advanced methodologies, which have contributed to a significant improvement in safety and efficacy.

Superior vena cava tear during transvenous lead extraction: Medical management in hemodynamically stable patients

INTRODUCTION

Superior vena cava (SVC) tear is the most lethal complication during transvenous lead extraction (TLE) with a mortality rate as high as 50%. Treatment involves aggressive attempts to maintain cardiac output and immediate sternotomy to localize and repair the vascular tear. Occlusion balloons have been developed to provisionally occlude the lacerated SVC and to provide hemodynamic stability allowing time for surgery. In case of mediastinal hematoma without hemodynamic instability, the strategy remains unclear.

METHODS AND RESULTS

We describe two cases of SVC tear during TLE. The first case was a 60-year-old man who presented with a right ventricular single-chamber defibrillator lead fracture and innominate vein stenosis. The RV lead was removed using a laser sheath causing a mediastinal hematoma with no active bleeding during surgical exploration few hours later. The second case was a 28-year-old man that presented with a right atrial (RA) lead fracture and RV lead insulation failure in a dual-chamber defibrillator (ICD).

CONCLUSION

Both the RA and RV leads were removed with mechanical sheaths, and a mediastinal hematoma was medically managed.

Success and Complication Rates of Transvenous Lead Extraction in a Developing High-Volume Extraction Center: The Zurich Experience

Introduction: Transvenous lead extractions are increasingly performed for malfunction or infection of cardiac implantable electronic devices, but they harvest a potential for complications and suboptimal success. Apart from multicenter registries and reports from highly experienced single centers, the outcome in individual newly developing high-volume centers starting a lead extraction program is less well established. We aimed to evaluate the clinical and radiological success and complication rate at our center, having started a lead extraction program less than a decade ago. Methods: We retrospectively analyzed patients who underwent transvenous lead extraction at the University Hospital Zurich from 2013 to 2021 regarding success as well as complications and compared our results to previously reported outcome rates. Results: A total of 346 patients underwent 350 transvenous lead extractions from January 2013 to December 2021. Combined radiological success was achieved in 97.7% and clinical success in 96.0% of interventions. Procedure-related major complications occurred in 13 patients (3.7%). Death within 30 days after transvenous lead extractions occurred in 13 patients (3.7%), with a procedure-related mortality of 1.4% (five patients). Summary: Transvenous lead extractions in newly developing high-volume centers can be performed with high clinical and radiological success rates, but procedure-related major complications may affect a relevant number of patients. Compared to large single or multicenter registries of experienced centers, the success rate may be lower and the complication rate higher in centers newly starting with lead extraction, which may have important implications for patient selection, procedural planning, proctoring, and safety measures.

Assessment of the impact of organisational model of transvenous lead extraction on the effectiveness and safety of procedure: an observational study

OBJECTIVES

To estimate the impact of the organisational model of transvenous lead extraction (TLE) on effectiveness and safety of procedures.

DESIGN

Post hoc analysis of patient data entered prospectively into a computer database.

SETTING

Data of all patients undergoing TLE in three centres in Poland between 2006 and 2021 were analysed.

PARTICIPANTS

3462 patients including: 985 patients undergoing TLE in a hybrid room (HR), with cardiac surgeon (CS) as co-operator, under general anaesthesia (GA), with arterial line (AL) and with transoesophageal echocardiography (TEE) monitoring (group 1), 68 patients-TLE in HR with CS, under GA, without TEE (group 2), 406 patients-TLE in operating theatre (OT) using 'arm-C' X-ray machine with CS under GA and with TEE (group 3), 154 patients-TLE in OT with CS under GA, without TEE (group 4), 113 patients-TLE in OT with anaesthesia team, using the 'arm-C' X-ray machine, without CS (group 5), 122 patients-TLE in electrophysiology lab (EPL), with CS under intravenous analgesia without TEE and AL (group 6), 1614 patients-TLE in EPL, without CS, under intravenous analgesia without TEE and AL (group 7).

KEY OUTCOME MEASURE

Effectiveness and safety of TLE depending on organisational model.

RESULTS

The rate of major complications (MC) was higher in OT/HR than in EPL (2.66% vs 1.38%), but all MCs were treated successfully and there was no MC-related death. The use of TEE during TLE increased probability of complete procedural succemss achieving about 1.5 times (OR=1.482; p<0.034) and were connected with reduction of minor complications occurrence (OR=0.751; p=0.046).

CONCLUSIONS

The most important condition to avoid death due to MC is close co-operation with cardiac surgery team, which permits for urgent rescue cardiac surgery. Continuous TEE monitoring plays predominant role in immediate decision on rescue sternotomy and improves the effectiveness of procedure.

Surgical Management of Cardiac Implantable Electronic Device Complications in Patients Unsuitable for Transvenous Lead Extraction

BACKGROUND

Although surgical approaches for infected or failing cardiac implantable electronic device (CIED) leads are more invasive than transvenous approaches, they are still required for patients considered unsuitable for transvenous procedures. In this study, surgical management with transvenous equipment for CIED complications was examined in patients unsuitable for transvenous lead extraction.Methods and Results: We retrospectively examined 152 consecutive patients who underwent CIED extraction between April 2009 and December 2021 at the Department of Cardiovascular Surgery, Nippon Medical School. Nine patients (5.9%; mean [±SD] age 61.7±16.7 years) who underwent open heart surgery were identified as unsuitable for the isolated transvenous approach. CIED types included 5 pacemakers and 4 implantable cardioverter-defibrillators; the mean [±SD] lead age was 19.5±7.0 years. Indications for surgical management according to Heart Rhythm Society guidelines included failed prior to transvenous CIED extraction (n=6), intracardiac vegetation (n=2), and severe lead adhesion (n=1). Transvenous CIED extraction tools were used in all patients during or before surgery. Additional surgical procedures with CIED extraction included epicardial lead implantation (n=4) and tricuspid valve repair (n=3). All patients were discharged; during the follow-up period (mean 5.7±3.7 years), only 1 patient died (non-cardiac cause).

CONCLUSIONS

Surgical procedures and transvenous extraction tools were combined in the removal strategy for efficacious surgical management of CIED leads. Intensive surgical procedures were safely performed in patients unsuitable for transvenous extraction.

Cardiac tamponade as an inherent but potentially nonfatal complication of transvenous lead extraction: Experience with 1126 procedures performed using mechanical tools

INTRODUCTION

Cardiac tamponade (CT) is one of the most common and dangerous complications of transvenous lead extraction (TLE). So far, however, there has been little discussion about the problem.

METHODS

We analyzed the occurrence of CT in a group of 1226 patients undergoing TLE at a single reference center between June, 2015 and February, 2021. Using standard mechanical devices as first-line tools, a total of 2092 leads had been extracted.

RESULTS

CT occurred in 18 patients (1.47%): due to injury to the wall of the right atrium in 14 patients (1.14%) and other cardiac walls in four patients (0.33%). Younger patient age at first implantation, female gender, high left ventricular ejection fraction (LVEF), lower New York Heart Association class, low Charlson comorbidity index, longer implant duration, and the number of previous procedures related to cardiac implantable electronic devices (CIED) are important patient-related risk factors for CT. Significant procedure-related risk factors include the number of extracted leads, extraction of atrial leads and longer dwell time of extracted leads. Intraoperative transoesophageal echocardiography (TEE) provides a lot of information about pulling on various cardiac structures and is able to detect a very early phase of bleeding to the pericardial sac. As a result of implementing best practices guidance in performing extraction procedures and close collaboration with cardiac surgeons that allowed immediate rescue intervention in our series of 18 CT cases, there were no procedure-related deaths (mortality 0%).

CONCLUSIONS

The need for rescue surgery due to CT has no influence on clinical and procedural success. Early diagnosed (TEE monitoring) and properly managed CT does not generate any additional risk in short- and long-term follow-up after TLE.

Effects and Complications of Subcutaneous Implantable Cardioverter-Defibrillator in the Prevention of Sudden Cardiac Death: A Narrative Review

An implantable cardioverter-defibrillator (ICD) is one of those devices that is a big boom for the prevention of sudden deaths due to heart failure. This particular device has been in use for just a couple of years, but its impact in the domain has brought about a considerable change in the way a specific issue of the cardiovascular system is tackled. Although subcutaneous or hypodermic implantable cardioverter-defibrillator (S-ICD) is considered to be a better alternative as far as transvenous implantable cardioverter-defibrillator (TV-ICD) is concerned, the former, being a newer introduction in the market, needs to be assessed in depth to clearly understand its effects and complications. Various types of research have been conducted on the efficacy of this device, and in most of the studies, the supremacy of this device is clearly evident when compared with other devices that are used for the same purpose. Better innovations in subcutaneous or hypodermic implantable cardioverter-defibrillators would enable them to be manufactured in a more efficient and cost-effective way so that a huge lot of people are benefited from this device. This review article is a whole peep into the various studies done in this domain, thereby providing adequate scientific insights about subcutaneous or hypodermic implantable cardioverter-defibrillators in a very simple and comprehensive manner.

The role of cardiac surgery in transvenous lead extraction. A high-volume center experience with 3207 procedures

Introduction

The guidelines stress the importance of cardiac surgery in the management of life-threatening complications arising from lead removal.

Aim

To delineate the roles of the cardiac surgeon during transvenous lead extraction (TLE).

Material and methods

3207 patients (38.7% F), average age 65.7 years, underwent the extraction of PM/ICD leads using standard non-powered mechanical systems within the last 14 years.

Results

Procedural success 96.1%, clinical success 97.8%, procedure-related death 0.18%, major complications 1.9% (cardiac tamponade 1.2%, hemothorax 0.2%, tricuspid valve damage 0.3%, stroke and pulmonary embolism < 1%). The roles for cardiac surgery in TLE have been categorized into five areas: 1. Emergency cardiac surgery (1.18% of all patients), 2. Late surgical intervention (TLE-related tricuspid valve dysfunction) (0.44%), 3. Cardiac surgery complementing partially successful TLE (0.68%: removal of lead fragments), 4. Epicardial pacemaker implantation through sternotomy for the above-mentioned reasons (0.65%), 5. Delayed surgical intervention after TLE to place epicardial LV leads (0.53%). Additionally, surgical experience can help in prevention and treatment of wound infection after TLE.

Conclusions

Emergency cardiac surgery (mainly due to severe bleeding) is still the most frequent reason for intervention (33.63% (38/113) of all surgical procedures). The other areas of surgical interventions in lead management are: cardiac surgery complementing partially successful TLE, repair or replacement of the malfunctioning tricuspid valve secondary to lead extraction and implantation of permanent epicardial pacing leads after sternotomy or epicardial left ventricle lead to optimize cardiac resynchronization. Experience of a single high-volume lead extraction center confirms the need for close collaboration between the cardiologist and the cardiac surgeon, whose role goes far beyond mere surgical standby.

The role of cardiac surgeon in transvenous lead extraction: experience from 3462 procedures

INTRODUCTION

The professional society guidelines recommend that transvenous lead extraction (TLE) operating teams collaborate closely with cardiac surgeons in the management of life-threatening complications.

METHODS AND RESULTS

We assessed the role of cardiac surgeons participating in 3462 TLE procedures at a high-volume center between 2006 and 2021. The roles for cardiac surgery in TLE can be categorized into five areas: emergency surgical interventions for the management of cardiac laceration and severe bleeding (1.184%), cardiac surgery complementing partially successful TLE or vegetation removal (0.693%), delayed surgical treatment of TLE-related tricuspid valve dysfunction (0.751%), epicardial pacemaker implantation through sternotomy during emergency, complementing or delayed surgical interventions (0.607%) and delayed epicardial lead implantation (0.491%). Isolated damage to the wall of the right atrium was the most common cause of cardiac tamponade (53.66% of emergency surgeries) followed by injury to the right ventricle and vena cava (both 7.317%).

CONCLUSIONS

Emergency cardiac surgery for the management of severe hemorrhagic complications is still the most common treatment option. The remaining areas include surgery complementing partially successful TLE: repair of tricuspid valve or epicardial ventricular lead placement to achieve permanent cardiac resynchronization. The experience at a single high-volume TLE center indicates the necessity of close collaboration with the cardiac surgeons whose roles appear broader than the mere surgical standby. Mortality in patients who survived cardiac surgery during transvenous lead extraction does not differ from the survival of other patients after TLE without complications requiring surgical intervention. This article is protected by copyright. All rights reserved.

Efficacy and mortality of rotating sheaths versus laser sheaths for transvenous lead extraction: a meta-analysis

BACKGROUND

Rotating and laser sheaths are both routinely used in transvenous lead extraction (TLE) which can lead to catastrophic complications including death. The efficacy and risk of each approach are uncertain. To perform a meta-analysis to compare success and mortality rates associated with rotating and laser sheaths.

METHODS

We searched electronic academic databases for case series of consecutive patients and randomized controlled trials published 1998-2017 describing the use of rotating and laser sheaths for TLE. Among 48 studies identified, rotating sheaths included 1,094 patients with 1,955 leads in 14 studies, and laser sheaths included 7,775 patients with 12,339 leads in 34 studies. Patients receiving rotating sheaths were older (63 versus 60 years old) and were more often male (74% versus 72%); CRT-P/Ds were more commonly extracted using rotating sheaths (12% versus 7%), whereas ICDs were less common (37% versus 42%), p > 0.05 for all. Infection as an indication for lead extraction was higher in the rotating sheath group (59.8% versus 52.9%, p = 0.002). The mean time from initial lead implantation was 7.2 years for rotating sheaths and 6.3 years for laser sheaths (p > 0.05).

RESULTS

Success rates for complete removal of transvenous leads were 95.1% in rotating sheaths and 93.4% in laser sheaths (p < 0.05). There was one death among 1,094 patients (0.09%) in rotating sheaths and 66 deaths among 7,775 patients (0.85%) in laser sheaths, translating to a 9.3-fold higher risk of death with laser sheaths (95% CI 1.3 to 66.9, p = 0.01).

CONCLUSIONS

Laser sheaths were associated with lower complete lead removal rate and a 9.3-fold higher risk of death.

Predictors of perforation during lead extraction: Results of the Canadian Lead ExtrAction Risk (CLEAR) study

BACKGROUND

Transvenous lead extraction can have serious adverse events, such as cardiac or vascular perforation. Risk factors have not been well characterized.

OBJECTIVE

The purpose of this study was to identify factors associated with perforation and death, and to characterize lead extraction in a large contemporary population.

METHODS

We performed a retrospective multicenter study examining patients undergoing lead extraction at 8 Canadian institutions from 1996 through 2016. Demographic and clinical data were used to identify variables associated with perforation and mortality using logistic regression modeling.

RESULTS

A total of 2325 consecutive patients (age 61.9 ±16.5 years) underwent extraction of 4527 leads. Perforation rate was 2.7% (63/2325) and 30-day mortality was 1.6% (38/2325), with mortality of 0.4% due to perforation (10/2325). Variables associated with perforation included no previous cardiac surgery (odds ratio [OR] 3.33; 95% confidence interval [CI] 1.54-7.19; P = .002), female sex (OR 3.27; 95% CI 1.91-5.60; P <.001); left ventricular ejection fraction ≥40% (OR 2.81; 95% CI 1.28-6.14; P = .010); lead age >8 years (OR 2.64; 95% CI 1.52-4.60; P <.001); ≥2 leads extracted (OR 2.49; 95% CI 1.23-5.04; P = .011); and diabetes (OR 2.12; 95% CI 1.16-3.86; P = .014). Variables associated with death included infection as indication for extraction (OR 3.85; 95% CI 1.38-10.73; P = .010); anemia (OR 3.14; 95% CI 1.38-6.61; P = .003), and patient age (OR 1.04; 95% CI 1.01-1.07; P = .012).

CONCLUSION

Risk factors associated with perforation in lead extraction include no history of cardiac surgery, female sex, preserved left ventricular ejection fraction, lead age >8 years, ≥2 leads extracted, and diabetes.

A Study of Major and Minor Complications of 1500 Transvenous Lead Extraction Procedures Performed with Optimal Safety at Two High-Volume Referral Centers

Background: Transvenous lead extraction (TLE) is the preferred management strategy for complications related to cardiac implantable electronic devices. TLE sometimes can cause serious complications. Methods: Outcomes of TLE procedures using non-powered mechanical sheaths were analyzed in 1500 patients (mean age 68.11 years; 39.86% females) admitted to two high-volume centers. Results: Complete procedural success was achieved in 96.13% of patients; clinical success in 98.93%, no periprocedural death occurred. Mean lead dwell time in the study population was 112.1 months. Minor complications developed in 115 (7.65%), major complications in 33 (2.20%) patients. The most frequent minor complications were tricuspid valve damage (TVD) (3.20%) and pericardial effusion that did not necessitate immediate intervention (1.33%). The most common major complication was cardiac laceration/vascular tear (1.40%) followed by an increase in TVD by two or three grades to grade 4 (0.80%). Conclusions: Despite the long implant duration (112.1 months) satisfying results without procedure-related death can be obtained using mechanical tools. Lead remnants or severe tricuspid regurgitation was the principal cause of lack of clinical and procedural success. Worsening TR(Tricuspid regurgitation) (due to its long-term consequences), but not cardiac/vascular wall damage; is still the biggest TLE-related problem; when non-powered mechanical sheaths are used as first-line tools.

Analysis of Risk Factors for Major Complications of 1500 Transvenous Lead Extraction Procedures with Especial Attention to Tricuspid Valve Damage

Background: Transvenous lead extraction (TLE) is a relatively safe procedure, but it may cause severe complications such as cardiac/vascular wall tear (CVWT) and tricuspid valve damage (TVD). Methods: The risk factors for CVWT and TVD were examined based on an analysis of data of 1500 extraction procedures performed in two high-volume centers. Results: The total number of major complications was 33 (2.2%) and included 22 (1.5%) CVWT and 12 (0.8%) TVD (with one case of combined complication). Patients with hemorrhagic complications were younger, more often women, less often presenting low left ventricular ejection fraction (LVEF) and those who received their first cardiac implantable electronic device (CIED) earlier than the control group. A typical patient with CVWT was a pacemaker carrier, having more leads (including abandoned leads and excessive loops) with long implant duration and a history of multiple CIED-related procedures. The risk factors for TVD were similar to those for CVWT, but the patients were older and received their CIED about nine years earlier. Any form of tissue scar and technical problems were much more common in the two groups of patients with major complications. Conclusions: The risk factors for CVWT and TVD are similar, and the most important ones are related to long lead dwell time and its consequences for the heart (various forms of fibrotic scarring). The occurrence of procedural complications does not affect long-term survival in patients undergoing lead extraction.

Long-term outcomes of non-systematic device reimplantation following lead extraction in selected patients

Following the removal of cardiovascular implantable electronic devices (CIEDs), reassessment of the need for a new device is vital. Some patients may have exhibited an improvement in rhythm or cardiac function and may thus no longer meet the guideline requirements for reimplantation. However, the long-term outcomes of non-systematic device reimplantation remain unknown. In the present study, it was hypothesized that the implantation of pacing systems in selected patients following lead extraction is safe. In order to confirm this hypothesis, a total of 854 patients (aged between 28 and 82 years) who underwent the removal of a CIED were enrolled in the present study and they were all reassessed to determine whether a new device following lead extraction was necessary. In order to determine which patients would undergo non-systematic device reimplantation, the standard guidelines, the criteria and the wishes of the patient were all taken into consideration. Patients remained device-free unless an adverse clinical event occurred that required reimplantation. The primary study endpoint was the rate of sudden death or reimplantation. Between January, 2014 and December, 2019, 854 consecutive patients underwent pacing system extraction, of whom 210 patients (24.6%) underwent non-systematic device reimplantation following careful reassessment (the non-reimplantation group). Among the 210 patients, 162 (77.1%) were fitted with pacemakers, 26 (12.4%) underwent cardiac resynchronization therapy or cardiac resynchronization therapy-defibrillator and 22 (10.5%) were implanted with a cardioverter-defibrillator. During a mean follow-up period of 40.4 months, 86 patients reached the primary endpoint of the study, including 54 out of 210 patients (25.7%) who experienced an adverse clinical event that required reimplantation and 32 out of 210 patients (15.2%) who experienced sudden death. Reimplantation of a new device was not required in ~25% of the patients. On the whole, the present study demonstrates that following pacing system removal, non-systematic device reimplantation associated with close surveillance is safe for selected patients.

Strategies to increase the INGEVITY lead strength during lead extraction procedures based on laboratory bench testing

Background

The INGEVITY lead (Boston Scientific, St Paul, MN, USA) has excellent clinical performance. However, its single filar design results in decreased lead tensile strength and a possible challenging extraction. This study's goal is to evaluate techniques for extracting the INGEVITY lead.

Methods

Two‐ and three‐dimensional models were created to simulate lead extraction from a right atrial appendage lead implant with a left subclavian approach and lead/fibrosis attachment sites. Standard and unique lead extraction preparation strategies were evaluated. Traction forces were measured from a superior approach alone or in combination with a femoral approach.

Results

For lead extraction via the superior approach, leaving the terminal on the lead was the only factor influencing maximum tolerated load (p‐value = .0007). Scar attachment provided greater lead tensile strength by transferring traction loading forces to the polyurethane outer insulation but dependent on insulation integrity. The strongest extraction rail was seen with a simulated femoral snaring of a locking stylet within the INGEVITY lead. Deployed screw retraction was most successful by rotating a Philips LLD#2 stylet (Philips Healthcare, Amsterdam, Netherlands) within the lead.

Conclusion

Results from in vitro simulations of INGEVITY lead extraction from an atrial location found the lead has low maximum tensile strength resulting in a poor extraction rail with common extraction tools and methods. However, the strength of the INGEVITY Lead extraction rail can be significantly increased by leaving the lead terminal intact and femoral snaring of the locking stylet within the lead. Such techniques may improve extraction of the INGEVITY lead.

Implant Fibrosis and the Underappreciated Role of Myofibroblasts in the Foreign Body Reaction

Body implants and implantable medical devices have dramatically improved and prolonged the life of countless patients. However, our body repair mechanisms have evolved to isolate, reject, or destroy any object that is recognized as foreign to the organism and inevitably mounts a foreign body reaction (FBR). Depending on its severity and chronicity, the FBR can impair implant performance or create severe clinical complications that will require surgical removal and/or replacement of the faulty device. The number of review articles discussing the FBR seems to be proportional to the number of different implant materials and clinical applications and one wonders, what else is there to tell? We will here take the position of a fibrosis researcher (which, coincidentally, we are) to elaborate similarities and differences between the FBR, normal wound healing, and chronic healing conditions that result in the development of peri-implant fibrosis. After giving credit to macrophages in the inflammatory phase of the FBR, we will mainly focus on the activation of fibroblastic cells into matrix-producing and highly contractile myofibroblasts. While fibrosis has been discussed to be a consequence of the disturbed and chronic inflammatory milieu in the FBR, direct activation of myofibroblasts at the implant surface is less commonly considered. Thus, we will provide a perspective how physical properties of the implant surface control myofibroblast actions and accumulation of stiff scar tissue. Because formation of scar tissue at the surface and around implant materials is a major reason for device failure and extraction surgeries, providing implant surfaces with myofibroblast-suppressing features is a first step to enhance implant acceptance and functional lifetime. Alternative therapeutic targets are elements of the myofibroblast mechanotransduction and contractile machinery and we will end with a brief overview on such targets that are considered for the treatment of other organ fibroses.

Predictors of lead break during transvenous lead extraction

BACKGROUND

The incidence, predictors, and clinical impact of lead break during transvenous lead extraction (TLE) were previously unknown.

METHODS

We included consecutive patients who underwent TLE between September 2013 and July 2019 at our institute. Lead break during removal was defined as lead stretching and becoming misshapen, as assessed by fluoroscopy.

RESULTS

A total of 246 patients underwent TLE for 501 leads. At a patient level, complete success was achieved in 226 patients (91.9%). At a lead level, 481 leads (96.0%) were completely removed and 101 leads (20.1%) were broken during the procedure. Of 392 identified pacemaker leads, 71 (18.3%) were broken during the TLE procedure. A multivariable analysis confirmed high lead age (odds ratio [OR] 1.12, 95% confidence interval (CI) 1.07-1.17; P < .001), passive leads (OR 2.29 95% CI 1.09-4.80; P = .028), coradial leads (OR 3.45 95% CI 1.72-6.92; P < .001), and insulators made of nonpolyurethane (OR 2.38 95% CI 1.03-5.26; P = .04) as predictors of lead break. Broken leads needed longer procedure times and were associated with a higher rate of cardiac tamponade.

CONCLUSIONS

Lead age, coradial bipolar leads, passive leads, and leads without polyurethane insulation were predictors of lead break and could increase the difficulty of lead extraction.

Location of Superior Vena Cava Tears in Transvenous Lead Extraction

BACKGROUND

Superior vena cava (SVC) tears are rare but potentially lethal complications associated with transvenous lead extraction. When lacerations occur, surgeons need to be prepared for an emergent response. Nonetheless, little is known about the precise whereabouts of these lesions. Understanding the location and injury patterns enables a more anticipated and targeted surgical response.

METHODS

We collected data via physician interviews after an SVC laceration occurred. These physicians were identified through the US Food and Drug Administration's Manufacturer and User Facility Device Experience database and independent physician reports of adverse events. We identified 116 reports of SVC tears between July 1, 2016, and July 31, 2018. For an SVC tear to be included in our registry, a cardiothoracic surgeon had to be physically present to confirm the injury via emergent sternotomy. In each case, the surgeon recorded the SVC injury's exact location after a repair was attempted.

RESULTS

During the study period, 116 SVC tears were confirmed by sternotomy. Tears occurred in any combination of the following locations: SVC-innominate vein, body of the SVC, and SVC-right atrial junction. The majority of tears (n = 72; 62%) were located in the isolated body of the SVC, followed by the SVC-right atrial junction (n = 23;19.8%) and the SVC-innominate junction (n = 17;14.6%). Combined tears were rare, accounting for only 3.6% (n = 4) of the adverse events recorded.

CONCLUSIONS

Most SVC tears occurred in the isolated body of the SVC. The second most common location was the SVC-right atrial junction. The SVC-innominate junction was the third most common location for these injuries. Combined tears were uncommon.

Major adverse clinical events associated with implantation of a leadless intracardiac pacemaker

BACKGROUND

Leadless intracardiac pacemakers were developed to avoid the complications of transvenous pacing systems. The Medtronic Micra™ transcatheter pacemaker is one such system. We found an unexpected number of major adverse clinical events (MACE) in the Food and Drug Administration's Manufacturers and User Facility Device Experience (MAUDE) database associated with Micra implantation.

OBJECTIVE

The purpose of this study was to describe these MACE and compare them to implant procedure MACE in MAUDE for Medtronic CapSureFix™ active-fixation transvenous pacing leads.

METHODS

During January 2021, we queried the MAUDE database for reports of MACE for Micra pacemakers and CapSureFix leads using the simple search terms "death," "tamponade," and "perforation." Reports from 2016-2020 were included.

RESULTS

The search identified 363 MACE for Micra and 960 MACE for CapSureFix leads, including 96 Micra deaths (26.4%) vs 23 CapSureFix deaths (2.4%) (P <.001); 287 Micra tamponades (79.1%) vs 225 tamponades for CapSureFix (23.4%) (P <.001); and 99 rescue thoracotomies for Micra (27.3%) vs 50 rescue thoracotomies for CapSureFix (5.2%) (P <.001). More Micra patients required cardiopulmonary resuscitation (21.8% vs 1.1%) and suffered hypotension or shock (22.0% vs 5.8%) than CapSureFix recipients (P <.001). Micra patients were more likely to survive a myocardial perforation or tear if they had surgical repair (P = .014).

CONCLUSION

Micra leadless pacemaker implantation may be complicated by myocardial and vascular perforations and tears that result in cardiac tamponade and death. We estimate the incidence is low (<1%). Rescue surgery to repair perforations may be lifesaving. MACE are significantly less for implantation of CapSureFix transvenous ventricular pacing leads.

A systematic review of the quality of cardiovascular surgery studies that extracted data from the MAUDE database

OBJECTIVE

To investigate opportunities and limitations of using the Manufacturer and User Facility Device Experience (MAUDE) database for cardiovascular surgery research, we analyzed the quality of studies having ever used MAUDE, in the field of cardiovascular surgery.

METHODS

We systematically searched the Cochrane Library, PubMed, EMBASE, and Google Scholar for randomized and nonrandomized studies, from inception to July 2019. Two authors evaluated the quality of the retrieved observational studies, according to the National Institutes of Health quality assessment tool for either case series or cross-sectional studies. These tools quantify the quality of case series and cohorts/cross-sectional studies, respectively, with nine and 14 queries.

RESULTS

Fifty-eight studies were included in the final qualitative review. Of 58 identified studies, 32 were case series, 8 were abstracts of case series, and 13 were reviews or case discussion with an included series from MAUDE. Also, five articles were cross-sectional studies. Of the 32 formal case series, 26 (81%) were found to have poor quality. The most common reasons for a poor quality designation included a lack of consecutive participants, undetermined comparability of participants, and undetermined follow-up adequacy. Only one out of five cross-sectional studies had fair quality; four others were evaluated as poor quality studies.

CONCLUSIONS

Cardiovascular surgery studies using the MAUDE database, whether case series or cross-sectional design, are mostly of poor quality. Their low quality is partly caused by poor study design, but mainly by intrinsic limitations to the MAUDE database: cases recruited are not consecutive; patient characteristics are not detailed enough to allow a meaningful comparison of patient characteristics between different patient entries; outcome measures are unclear; there is a limited follow-up; and time-to-event data are lacking. We conclude that the quality of cardiovascular surgery publications that rely on data from MAUDE could be improved if investigators were to extract all relevant data points from MAUDE entries, then apply standard quality assessment tools in compiling and reporting the data. MAUDE might be improved if it used medical case report standards during the process of reporting and indexing adverse events. To calculate the incidence rate of any adverse event, all event-free cases, as well as all adverse events in patients using a device, are required. Neither of these two variables is available in the MAUDE at the time of writing.

Benefits of routine prophylactic femoral access during transvenous lead extraction

BACKGROUND

The number of patients requiring lead extraction has been increasing in recent years. Despite significant advances in operator experience and technique, unexpected complications may occur. Prophylactic placement of femoral sheaths allows for immediate endovascular access for emergency procedures and may shorten response time in the event of complications.

OBJECTIVE

The purpose of this study was to assess the benefits of routine prophylactic femoral access in patients undergoing transvenous lead extraction (TLE) and to evaluate the methods, frequency, and efficacy of the emergency measures used in those patients.

METHODS

We conducted a retrospective analysis of patients who underwent TLE from January 2012 to February 2019. The data were analyzed with regard to procedural complications and deployment of emergency measures via femoral access.

RESULTS

Two hundred eighty-five patients (mean age 65.3 ± 15.5 years) were included in the study. Median lead dwell time was 84 months (interquartile range 58-144). Overall complication rate was 4.2% (n = 12), with 1.8% major complications (n = 5). Clinical success rate was 97.2%. Procedure-related mortality was 1.1% (n = 3). Femoral sheaths were actively engaged in 9.1% (n = 26) of cases. Deployment of snares was the most common intervention (n = 10), followed by prophylactic (n = 6) or emergency placement (n = 1) of occlusion balloons, temporary pacing (n = 3), venous angioplasty (n = 3), diagnostic venography (n = 3), and extracorporeal membrane oxygenation (n = 1). We did not observe any femoral vascular complications due to prophylactic sheath placement.

CONCLUSION

Routine prophylactic placement of femoral sheaths shortens response time and quickly establishes control in the event of various complications that may occur during TLE procedures.

In Vivo Intravascular Pacing Using a Wireless Microscale Stimulator

Millions of patients worldwide are implanted with permanent pacemakers for the treatment of cardiac arrhythmias and conduction disorders. The increased use of these devices has established a growing clinical need to mitigate associated complications. Pacemaker leads, in particular, present the primary risks in most implants. While wireless power transfer holds great promise in eliminating implantable device leads, anatomical constraints limit efficient wireless transmission over the necessary operational range. We thereby developed a transmitter-centered control system for wireless power transfer with sufficient power for continuous cardiac pacing. Device safety was validated using a computational model of the system within an MRI-based anatomical model. The pacer was then fabricated to meet the acute constraints of the anterior cardiac vein (ACV) to enable intravascular deployment while maintaining power efficiency. Our computational model revealed the wireless system to operate at > 50 times below the tissue energy absorption safety criteria. We further demonstrated the capacity for ex vivo pacing of pig hearts at 60 beats per minute (BPM) and in vivo pacing at 120 BPM following pacer deployment in the ACV. This work thus established the capacity for wireless intravascular pacing with the potential to eliminate complications associated with current lead-based deep tissue implants.

Salvage of Exposed Cardiac Implants Using Fasciocutaneous Rotation Flaps

INTRODUCTION

Implantation rates of cardiac implantable electrophysiological devices (CIEDs) are rising, mainly because of the expansion of implantable cardioverter-defibrillators indications for primary prevention. As the CIED usage increases, CIED-related complications are also in rise. Transvenous approach and laser utilization techniques are replacing the open heart surgeries, for removal of CIED systems that are suspected to be infected. In this study, we aimed to share our new method of fasciocutaneous flap coverage results of patients with exposed CIED systems who were not eligible for the CIED replacement surgery for various reasons.

PATIENTS AND METHODS

Patients operated with rotational fasciocutaneous flaps with addition of pectoralis fascia, owing to their exposed CIEDs between June 2016 and January 2019, were enlisted. Patients with signs of infection whether systemic or limited to the CIED pocket with or without positive blood cultures were referred to infectious diseases department and not included in this study. Patients included in the study were evaluated retrospectively in terms of demographic data, implanted CIED type, time elapsed from implantation to exposure, from referral to flap coverage operation, total follow-up time, survival ratios during follow-up, and complications related to flap coverage operation. In addition, indications for CIED implantation, patient comorbidities, and culture results obtained from the capsule encompassing the CIED battery unit were included to the evaluation.

RESULTS

A total of 13 patients with exposed CIEDs have undergone total capsulectomy and CIED system coverage with rotational fasciocutaneous flaps. The mean patient age ± SD was 60.2 ± 13.4 years. The average time elapsed from CIED implantation to exposure was 27.3 ± 15.4 months. The average time spanned from initial referral to operation was 6 ± 1.6 days. The most prevalent comorbidity was diabetes mellitus. The average time elapsed during operation for pectoral fascia incorporated rotation flaps was 90 ± 10.6 minutes. Coagulase negative staphylococci were the dominant species (46.5%) obtained from capsule cultures. Apart from 1 case of hematoma, no early or late operation-related complication was encountered.

CONCLUSIONS

A more precise definition of contamination and infection has to be made in guidelines, which may lead the first group to be treated without extraction. Surgical method defined in this study can be used for the treatment of patients in contaminated CIED subgroup, conserving individuals from risks of device extraction.

Morphometric Characterization of Human Coronary Veins and Subvenous Epicardial Adipose Tissue-Implications for Cardiac Resynchronization Therapy Leads

Subvenous epicardial fat tissue (SEAT), which acts as an electrical insulation, and the venous diameter (VD) both constitute histomorphological challenges for optimal application and lead design in cardiac synchronization therapy (CRT). In this study, we characterized the morphology of human coronary veins to improve the technical design of future CRT systems and to optimize the application of CRT leads. We retrospectively analyzed data from cardiac computed tomography (CT) of 53 patients and did studies of 14 human hearts using the postmortem freeze section technique and micro CT. Morphometric parameters (tributary distances, offspring angles, luminal VD, and SEAT thickness) were assessed. The left posterior ventricular vein (VVSP) had a mean proximal VD of 4.0 ± 1.4 mm, the left marginal vein (VMS) of 3.2 ± 1.5 mm and the anterior interventricular vein (VIA) of 3.9 ± 1.3 mm. More distally (5 cm), VDs decreased to 2.4 ± 0.6 mm, 2.3 ± 0.7 mm, and 2.4 ± 0.6 mm, respectively. In their proximal portions (15 mm), veins possessed mean SEAT thicknesses of 3.2 ± 2.4 (VVSP), 3.4 ± 2.4 mm (VMS), and 4.2 ± 2.8 mm (VIA), respectively. More distally (20-70 mm), mean SEAT thicknesses decreased to alternating low levels of 1.3 ± 1.1 mm (VVSP), 1.7 ± 1.1 mm (VMS), and 4.3 ± 2.6 mm (VIA), respectively. In contrast to the VD, SEAT thicknesses alternated along the further distal vein course and did not display a continuous decrease. Besides the CRT responsiveness of different areas of the LV myocardium, SEAT is a relevant electrophysiological factor in CRT, potentially interfering with sensing and pacing. A sufficient VD is crucial for successful CRT lead placement. Measurements revealed a trend toward greater SEAT thickness for the VIA compared to VVSP and VMS, suggesting a superior signal-to-noise-ratio in VVSP and VMS.

Quantitative and Qualitative Assessment of Adhesive Thrombo-Fibrotic Lead Encapsulations (TFLE) of Pacemaker and ICD Leads in Arrhythmia Patients-A Post Mortem Study

The demand for cardiac implantable electronic devices for arrhythmia therapy is still unabated and rising. Despite onward optimizations, lead-related problems such as infections or fractures often necessitate lead extraction. Due to adhesive thrombo-fibrotic lead encapsulations (TFLE) transvenous lead extraction is challenging and risky. However, knowledge on TFLEs and possible correlations with technical lead parameters and dwelling time (DT) were hitherto insufficiently studied. Therefore, we analyzed TFLEs of 62 lead from 35 body donor corpses to gain information for a potential lead design optimization. We examined both TFLE topography on the basis on anatomical landmarks and histo-morphological TFLE characteristics by means of histological paraffin sections and scanning electron microscopy of decellularized samples. The macroscopic analysis revealed that all leads were affected by TFLEs, mainly in the lead bearing veins. Half (47.2%) of the right-ventricular leads possessed adhesions to the tricuspid valve. On average, 49.9 ± 21.8% of the intravascular lead length was covered by TFLE of which 82.8 ± 16.2% were adhesive wall bindings (WB). The discrete TFLEs with at least one WB portion had a mean length of 95.0 ± 64.3 mm and a maximum of 200 mm. Neither sex, DT nor certain technical lead parameters showed distinct tendencies to promote or prevent TFLE. TFLE formation seems to start early in the first 1-2 weeks after implantation. The degree of fibrotization of the TFLE, starting with a thrombus, was reflected by the amount of compacted collagenous fibers and likewise largely independent from DT. TFLE thickness often reached several hundred micrometers. Calcifications were occasionally seen and appeared irregularly along the TFLE sheath. Leadless pacemaker systems have the advantage to overcome the problem with TFLEs but hold their own specific risks and limitations which are not fully known yet.

A Multi-Dimensional Analysis of a Novel Approach for Wireless Stimulation

The elimination of integrated batteries in biomedical implants holds great promise for improving health outcomes in patients with implantable devices. However, despite extensive research in wireless power transfer, achieving efficient power transfer and effective operational range have remained a hindering challenge within anatomical constraints.

OBJECTIVE

We hereby demonstrate an intravascular wireless and batteryless microscale stimulator, designed for (1) low power dissipation via intermittent transmission and (2) reduced fixation mechanical burden via deployment to the anterior cardiac vein (ACV, ∼3.8 mm in diameter).

METHODS

We introduced a unique coil design circumferentially confined to a 3 mm diameter hollow-cylinder that was driven by a novel transmitter-based control architecture with improved power efficiency.

RESULTS

We examined wireless capacity using heterogenous bovine tissue, demonstrating >5 V stimulation threshold with up to 20 mm transmitter-receiver displacement and 20° of misalignment. Feasibility for human use was validated using Finite Element Method (FEM) simulation of the cardiac cycle, guided by pacer phantom-integrated Magnetic Resonance Images (MRI).

CONCLUSION

This system design thus enabled sufficient wireless power transfer in the face of extensive stimulator miniaturization.

SIGNIFICANCE

Our successful feasibility studies demonstrated the capacity for minimally invasive deployment and low-risk fixation.

Is Venoplasty an Alternative to Lead Extraction for Patients With Venous Obstruction?

BACKGROUND

Indications for cardiovascular implantable electronic devices (CIEDs) have increased over time. Patients may require lead replacement or implantation due to lead failure or need for device upgrade. Venous obstruction is a common finding in these patients and often poses difficulties for operators. Venoplasty as an alternative to lead extraction emerges as an important intervention in the treatment of selected patients, particularly with a view to minimising procedural risk.

METHODS

Nine (9) patients with CIED related venous occlusion were treated with venoplasty at our institution between April 2006 and October 2019. Six (6) of nine patients were initially referred to our institution for consideration of transvenous lead extraction in the setting of venous occlusion. These patients are the subjects of the case series. Patient demographics, indication for venoplasty and procedural outcomes were examined.

RESULTS

We present a series of six patients in whom venoplasty has been performed at our centre as an alternative to lead extraction. Device and patient characteristics have been examined as well as radiation exposure and fluoroscopy time. The median age of our cohort was 64.5 years (range: 37-81 years) and 67% were female. Luminal calibre was improved in all patients allowing lead replacement, device upgrade or relief of symptoms. Procedural complications were not observed, and all patients remained free of symptoms related to venous occlusion at 3-month follow-up.

CONCLUSIONS

We present venoplasty as a viable alternative to lead extraction in high risk patients or in those who favour a less invasive approach.

Eligibility for subcutaneous implantable cardioverter-defibrillator in patients with left ventricular assist device

Purpose

The subcutaneous implantable cardioverter-defibrillator (S-ICD) could be a promising alternative to the conventional transvenous ICD in patients with LVAD due to its reduced risk of infection. However, surface ECG is altered following LVAD implantation and, since S-ICD detection is based on surface ECG, S-ICD could be potentially affected. The aim of the present study was to analyze S-ICD eligibility in patients with LVAD.

Methods

Seventy-five patients implanted with an LVAD were included in this prospective single-center study. The ECG-based screening test and the automated screening test were performed in all patients.

Results

Fifty-five (73.3%) patients had either a positive ECG-based or automated screening test. Out of these, 28 (37.3%) patients were found eligible for S-ICD implantation with both screening tests performed. ECG-based screening test was positive in 50 (66.6%) patients; automated screening test was positive in 33 (44.0%) patients. Three ECG-based screening tests could not be evaluated due to artifacts. With the automated screening test, in 9 (12.0%) patients, the test yielded no result.

Conclusions

Patients implanted with an LVAD showed lower S-ICD eligibility rates compared with patients without LVAD. With an S-ICD eligibility rate of maximal 73.3%, S-ICD therapy may be a feasible option in these patients. Nevertheless, S-ICD implantation should be carefully weighed against potential device-device interference. Prospective studies regarding S-ICD eligibility before and after LVAD implantation are required to further elucidate the role of S-ICD therapy in this population.

Use of the new rotating dilator sheath TightRail™ for lead extraction: A bicentric experience

AIM

The aim of this study is to assess the safety and efficacy of the new bidirectional rotational mechanical sheath TightRail™ (Spectranetics) for lead extraction.

METHODS AND RESULTS

This is a bicentric prospective study that included patients who underwent a transvenous lead extraction (TLE) in two Italian centers (San Raffaele Hospital and Humanitas Gavazzeni Hospital). From November 2016 to December 2018, 26 patients underwent a TLE procedure in which the TightRail™ was used. The new TightRail Sub-C was used in 20 (76%) patients to overcome the fibrosis between the vessel and the first rib. Median age was 69 (IQR 60.7-79.5) years. The indication for TLE were infection (57.7%) or lead dysfunction (42.3%). A total of 57 leads (range 1-4), 40 of which using the TightRail (range 1-4), were extracted. Overall mean implant duration was 98.2.0 ± 66.5 months. Mean age of the lead extracted with the TightRail sheath was 99.1 ± 70.2 months and was higher compared to that of the leads extracted manually (84.4 ± 60.3 months, P = .001). The overall clinical success was 100% and complete procedural success without the use of a snare was achieved in 98.3%. There were no cases of death or major complications and only two minor complications occurred. All patients were event-free at 6-month follow-up.

CONCLUSION

This initial experience using the TightRail™ suggests a high safety and efficacy profile for extractions in a wide range of lead age.

Financial and resource costs of transvenous lead extraction in a high-volume lead extraction centre

OBJECTIVES

Transvenous lead extraction (TLE) poses a significant economic and resource burden on healthcare systems; however, limited data exist on its true cost. We therefore estimate real-world healthcare reimbursement costs of TLE to the UK healthcare system at a single extraction centre.

METHODS

Consecutive admissions entailing TLE at a high-volume UK centre between April 2013 and March 2018 were prospectively recorded in a computer registry. In the hospital's National Health Service (NHS) clinical coding/reimbursement database, 447 cases were identified. Mean reimbursement cost (n=445) and length of stay (n=447) were calculated. Ordinary least squares regressions estimated the relationship between cost (bed days) and clinical factors.

RESULTS

Mean reimbursement cost per admission was £17 399.09±£13 966.49. Total reimbursement for all TLE admissions was £7 777 393.51. Mean length of stay was 16.3±15.16 days with a total of 7199 bed days. Implantable cardioverter-defibrillator and cardiac resynchronisation therapy defibrillator devices incurred higher reimbursement costs (70.5% and 68.7% higher, respectively, both p<0.001). Heart failure and prior valve surgery also incurred significantly higher reimbursement costs. Prior valve surgery and heart failure were associated with 8.3 (p=0.017) and 5.5 (p=0.021) additional days in hospital, respectively.

CONCLUSIONS

Financial costs to the NHS from TLE are substantial. Consideration should therefore be given to cost/resource-sparing potential of leadless/extravascular cardiac devices that negate the need for TLE particularly in patients with prior valve surgery and/or heart failure. Additionally, use of antibiotic envelopes and other interventions that reduce infection risk in patients receiving transvenous leads should be considered.

Algorithm for the analysis of pre-extraction computed tomographic images to evaluate implanted lead-lead interactions and lead-vascular attachments

BACKGROUND

The number of lead extractions is growing because of the greater population and increasing age of individuals with a cardiac implantable electronic device. Lead extraction procedures can be complex undertakings with risk of significant mortality, and vascular tears in the superior vena cava are of greatest concern.

OBJECTIVE

The purpose of this study was to study whether a novel algorithm that analyzes pre-extraction computed tomographic (CT) images can determine the likelihood and location of lead-lead interactions and lead-vessel attachment within patients' venous vasculatures. This information can be used to identify potential case challenges in the planning stages.

METHODS

We developed an algorithm to estimate the presence and position of lead-lead interactions and lead-vessel adherences by tracking distance between the leads and distance between the lead and superior vena cava in a sample of 12 patients referred to the United Heart and Vascular Clinic for lead extractions due to infection (n = 5), lead failure (n = 5), and tricuspid regurgitation (n = 2).

RESULTS

Preliminary results indicate that the developed algorithm successfully identified lead-lead and lead-vascular attachments compared to review of CT images by medical experts.

CONCLUSION

With future validation and clinical implementation, this algorithm could aid physician preparedness by minimizing intraprocedural emergencies and may improve patient outcomes.

Evaluation of Secrecy Capacity for Next-Generation Leadless Cardiac Pacemakers

Secure communication can be considered as an integral part of the next generation implantable medical devices. With the advent of Physical Layer Security (PLS) methods, confidential messages can be transmitted without the use of encryption keys. For analyzing the effectiveness of PLS for next-generation leadless cardiac pacemakers, we provide secrecy analysis using a performance metric of secrecy capacity. Secrecy capacity defines the secure transmission rate between legitimate nodes without leakage of information to an eavesdropper and depends on respective channel attenuations. The legitimate and eavesdropper channel attenuations are evaluated by 3D numerical electromagnetic simulations using a detailed human model. We do not assume eavesdropper to be located in specific directions or positions and considers it to be located anywhere around the body. We evaluate the secrecy capacity by defining a spherical grid for eavesdropper positions around the body with a radius of 1 m. The secrecy capacity of the entire space is evaluated by extrapolating the grid to different radial distances using free space path loss model. Moreover, by fixing application based secure communication rate, the entire space is divided into secure and in-secure volumes. The in-secure volume consists of all the eavesdropper positions from which the pacemaker can be eavesdropped. We also evaluated the angle from which the maximum leakage of information takes place and referred it as "Eve's sweet spot angle." Data for channel attenuations from phantom and in-vivo experiments is also utilized to validate and observe the differences between simulations and experiments. This article will help in design of the communication module of implanted leadless cardiac pacemakers with enhanced security on the physical layer.

Safety and In-Hospital Outcomes of Transvenous Lead Extraction for Cardiac Implantable Device-Related Infections: Analysis of 13 Years of Inpatient Data in the United States

OBJECTIVES

The aim of this study was to investigate the safety and in-hospital outcomes of transcutaneous lead extraction (TLE) associated with device-related infection (DRI) in the United States from 2003 to 2015.

BACKGROUND

DRI remains the most serious complication and the most common indication for lead extraction in patients with cardiac implantable electronic devices. The rates of DRI and associated lead extraction have been growing in line with the increasing number of cardiac implantable electronic device implantations worldwide.

METHODS

Data for this study were drawn from the National (Nationwide) Inpatient Sample. The International Classification of Diseases-9th Revision-Clinical Modification coding system was used to identify hospitalizations with TLE for DRI and to investigate the rates of major adverse events.

RESULTS

From a total of approximately 100 million unweighted hospitalizations over the 13-year study period, 12,257 unweighted observations were identified. This represents 59,082 (95% confidence interval [CI]: 58,982 to 59,182) patients who underwent TLE for DRI during the study period. A large majority of patients (75%) were older than 60 years. Patients were predominantly male (70%) and Caucasian (76%), and 80% had at least 1 comorbidity. The median length of stay was 8 days (interquartile range 5 to 14 days). At least 1 major adverse event occurred in 10.42% of procedures. The all-cause in-hospital mortality rate was 4.11%. Independent predictors of mortality were weight loss (adjusted odds ratio [aOR]: 4.02; 95% CI: 3.13 to 5.17), congestive heart failure (aOR: 3.28; 95% CI: 2.48 to 4.34), chronic kidney disease (aOR: 2.09; 95% CI: 1.70 to 2.56), pericardial complications (aOR: 2.87; 95% CI: 1.79 to 4.61), and procedure-related pulmonary injury (aOR: 2.06; 95% CI: 1.25 to 3.40).

CONCLUSIONS

These results reflect the high rate of complications and mortality for TLE due to DRI in real-world experience, highlighting the importance of comorbidities, especially congestive heart failure and chronic kidney disease, as significant predictors of mortality in these patients.

Transfemoral extraction of pacemaker and implantable cardioverter defibrillator leads using Needle's Eye Snare: a single-center experience of more than 900 leads

The femoral approach with the Needle's Eye Snare (NES) is often used for bailout after failure of the superior approach for transvenous lead extraction (TLE). The safety and efficacy of the NES as a first-line tool for TLE remain unclear. The medical records of patients who underwent TLE via the femoral approach utilizing the NES from May 2014 to June 2019 in Peking University People's Hospital were retrospectively reviewed. Nine hundred and eighty-five leads were extracted in 492 patients (369 men; mean age 72.8 ± 29.0 years). The median (range) number of leads extracted per patient was 2 (1-6). The mean indwelling time of all extracted leads was 112.6 ± 52.0 months. The complete procedure success rate, clinical success rate, and failure rate were 94.1% (463/492), 97.8% (481/492), and 1.1% (11/492), respectively. Major complications including death occurred in nine patients (1.9%), of whom eight developed cardiac tamponade. Among these eight patients, emergency pericardiocentesis followed by rescue surgical repair if necessary was successful in 6 (75.0%) and failed in 2 (25.0%). No significant differences were found in the clinical success rate or major complications rate between patients with pacemakers and implantable cardioverter defibrillators, or between patients with infected and uninfected leads. A femoral approach with the NES is safe and effective for TLE of both pacing and defibrillator leads and could be considered a first-line approach. Cardiac tamponade was the most frequent cardiovascular complication. A strategy of emergency pericardiocentesis followed by a rescue surgical approach seems to be reasonable technique to treat a cardiac tamponade.

Echocardiographic assessment of residuals after transvenous intracardiac lead extraction

Detection of residual fibrotic tissue, called ghosts, after lead extraction is a new phenomenon in cardiology. This paper aims at describing the phenomenon of ghosts and determining their characteristic features. The study group consisted of 580 consecutive patients who underwent transvenous lead extraction (TLE) due to local infection, endocarditis and a superfluous lead. Each patient was clinically examined with the application of transthoracic echocardiography and transesophageal echocardiography directly before and after TLE. In the study population ghosts were detected in 110 patients (19%), and in 470 cases (81%) fibrotic tissue residuals were not found. Ghosts were most often located along the originally implanted lead's route. Longer ghosts were found after the removal of cardiac resynchronization therapy (CRT) and dual chamber pacing (DDD) devices. The local infection and infective endocarditis are associated with a larger number of ghosts revealed after the removal procedure (p = 0.006). The type of the implanted device: CRT/ICD/double chamber pacemaker/single chamber pacemaker, similar to the number of leads, did not impact on the number of the detected ghosts. The relationship between abrasions of the leads and the presence of ghosts proved significant, however (p = 0.043). TLE is associated with the presence of fibrotic tissue residuals in approx. 19% of patients. Indications for lead extraction due to local infection and endocarditis yielded significantly more cases of ghosts than in the entire patient population. The presence of abrasions is a good predictor for the presence of ghosts on the leads.

The Diagnosis and Treatment of Pacemaker-Associated Infection

BACKGROUND

Approximately 105 000 cardiac electronic devices are newly implanted in Germany each year. Germany has the highest implantation rate with respect to population of any European country. Infections in cardiac implants are serious complications, with an associated in-hospital mortality of 5-15%. It is thus very important to optimize the diagnostic and therapeutic strategies by which such infections can be detected early and treated effectively.

METHODS

This review is based on pertinent publications retrieved by a search in PubMed, with special attention to the current recommendations of international medical specialty societies.

RESULTS

According to the international literature, the incidence of device-associated infection is 1.7% (in six months) for implanted defibrillators and 9.5% (in two years) for resynchronization devices. No absolute figures on infection rates are available for Germany. Infection can involve either the site where the impulse generator is implanted or the intravascular portion of the electrodes. The most important elements of the diagnostic evaluation are: assessment of the local findings; pathogen identification by culture of peripheral blood, swabs of the infected site, or material recovered at surgery; and transesophageal echocardiography to detect endocarditic deposits on the electrodes or cardiac valves. The treatment consists of appropriate antibiotic administration and the complete removal of all foreign material. These special extractions are generally performed via the transvenous route. With the aid of various sheath systems, the procedure can be carried out safely and effectively, with a success rate above 95% and a complication rate below 3%. The indications for the implantation of a new device after eradication of the infection should be critically reassessed.

CONCLUSION

Untreated infection carries a high mortality. Evaluation and treatment according to a standardized clinical algorithm facilitate correct and timely diagnosis and the choice of an appropriate therapeutic strategy.

Reported mortality with rotating sheaths vs. laser sheaths for transvenous lead extraction

Aims

Rotating sheaths and laser sheaths are commonly used for transvenous lead extraction. This study aims to compare observed mortality between both approaches.

Methods and results

The Manufacturer and User Facility Device Experience database was searched from 2011 to 2016 to determine number of deaths associated with each sheath. An independent analytics firm provided estimates for number of cases done, allowing calculation of market share. A sensitivity analysis was performed to determine relative risk (RR) of mortality at the calculated market share (36% rotating/64% laser) and two others. Additional sensitivity analyses assumed underreporting of deaths associated with rotating sheaths. An estimated 50 545 extractions were performed. Thirteen deaths were associated with rotating sheaths compared to 167 with laser sheaths. Of these, 92% (rotating) and 95% (laser) were due to cardiovascular injury. At the calculated market share, the RR of death was 7.2 times greater with laser sheaths [95% confidence interval (CI) 4.1–12.7, P < 0.0001]. At market share estimates of 25% rotating/75% laser and 45% rotating/55% laser, the RR of death with laser sheaths was 4.3 (95% CI 2.4–7.5, P < 0.0001) and 10.5 times greater (95% CI 6.0–18.5, P < 0.0001), respectively. The RR of death remained significant when assuming deaths with rotating sheaths were underreported and when deaths using both sheaths were attributed to the rotating sheath.

Conclusions

Lead extraction with laser sheaths appears to be associated with a higher risk of mortality compared to rotating sheaths. Further studies are warranted to confirm this finding.

Endovascular Occlusion Balloon for Treatment of Superior Vena Cava Tears During Transvenous Lead Extraction

Background:

Superior vena cava (SVC) tears are one of the most lethal complications in transvenous lead extraction. An endovascular balloon can occlude the SVC in the event of a laceration, preventing blood loss and offering a more controlled surgical field for repair. An early study demonstrated that proper use of this device is associated with reduced mortality. Thereafter, high-volume extractors at the Eleventh Annual Lead Management Symposium developed a best practice protocol for the endovascular balloon.

Methods:

We collected data on adverse events in lead extraction from July 1, 2016, to July 31, 2018. Data were prospectively collected from both a US Food and Drug Administration–maintained database and physician reports of adverse events as they occurred. We gathered case details directly from extracting physicians. Confirmed SVC tears were analyzed for patient demographics, case details, and index hospitalization mortality.

Results:

From July 1, 2016, to July 31, 2018, 116 confirmed SVC events were identified, of which 44.0% involved proper balloon use and 56.0% involved no use or improper use. When an endovascular balloon was properly used, 45 of 51 patients (88.2%) survived in comparison to 37 of 65 patients (56.9%) when a balloon was not used or improperly used ( P =0.0002). Furthermore, multivariate regression modeling found that proper balloon deployment was an independent, negative predictor of in-hospital mortality for patients who experienced an SVC laceration (odds ratio, 0.13; 95% CI, 0.04–0.40; P <0.001).

Conclusions:

From July 1, 2016, through July 31, 2018, patients undergoing lead extraction were more likely to survive SVC tears when treatment included an endovascular balloon.