Implantation of subcutaneous implantable cardioverter defibrillators in Europe: results of the European Heart Rhythm Association survey

Occurrence of premature battery depletion in a large multicentre registry of subcutaneous cardioverter-defibrillator patients

AIMS

Subcutaneous implantable cardioverter-defibrillators (S-ICDs) have become established in preventing sudden cardiac death, with some advantages over transvenous defibrillator systems, including a lower incidence of lead failures. Despite technological advancements, S-ICD carriers may suffer from significant complications, such as premature battery depletion (PBD), that led to an advisory for nearly 40 000 patients. This multicentre study evaluated the incidence of PBD in a large set of S-ICD patients.

METHODS AND RESULTS

Data from patients implanted with S-ICD models A209 and A219 between October 2012 and July 2023 across nine centres in Europe and the USA were reviewed. Incidence and implications of PBD, defined as clinically observed sudden drop in battery longevity, were analysed and compared to PBD with the definition of battery depletion within 60 months. Prospectively collected clinical data were obtained retrospectively from medical records, device telemetry, and manufacturer reports. This registry is listed on ClinicalTrials.gov (NCT05713708). Of the 1112 S-ICD devices analysed, 547 (49.2%) were equipped with a potentially affected capacitor linked to PBD occurrence, currently under Food and Drug Administration advisory. The median follow-up time for all patients was 46 [inter-quartile range (IQR) 24-63] months. Clinically suspected PBD was observed in 159 (29.1%) of cases, with a median time to generator removal or replacement of 65 (IQR 55-72) months, indicative of significant deviations from expected battery lifespan. Manufacturer confirmation of PBD was made in 91.7% of devices returned for analysis. No cases of PBD were observed in devices that were not under advisory.

CONCLUSION

This manufacturer-independent analysis highlights a notable incidence of PBD in patients equipped with S-ICD models under advisory, and the rate of PBD in this study corresponds to the rate currently estimated by the manufacturer. To the best of our knowledge, this provides the largest contemporary peer-reviewed study cohort investigating the actual incidence of PBD in S-ICD patients. These findings emphasize the importance of post-market registries in collaboration between clinicians and the manufacturer to optimize safety and efficacy in S-ICD treatment.

Fifteen years of subcutaneous implantable cardioverter-defibrillator therapy: Where do we stand, and what will the future hold?

The subcutaneous implantable cardioverter-defibrillator (S-ICD) has emerged as a feasible alternative to the transvenous ICD in the treatment of ventricular tachyarrhythmias in patients without indications for pacing or cardiac resynchronization therapy. Since its introduction, numerous innovations have been made and clinical experience has been gained, leading to its adoption in current practice and preference in certain populations. Moreover, emerging technologies like the extravascular ICD and the combination of the S-ICD with the leadless pacemaker offer new possibilities for the future. These advancements underscore the evolving role of the S-ICD in management of ventricular tachyarrhythmias. This review outlines implantation considerations, patient selection, and troubleshooting advancements in the last 15 years and provides insights into future perspectives.

Procedure, management, and outcome of subcutaneous implantable cardioverter-defibrillator extraction in clinical practice

AIMS

Subcutaneous implantable cardioverter-defibrillator (S-ICD) therapy is expanding rapidly. However, there are few data on the S-ICD extraction procedure and subsequent patient management. The aim of this analysis was to describe the procedure, management, and outcome of S-ICD extractions in clinical practice.

METHODS AND RESULTS

We enrolled consecutive patients who required complete S-ICD extraction at 66 Italian centres. From 2013 to 2022, 2718 patients undergoing de novo implantation of an S-ICD were enrolled. Of these, 71 required complete S-ICD system extraction (17 owing to infection). The S-ICD system was successfully extracted in all patients, and no complications were reported; the median procedure duration was 40 (25th-75th percentile: 20-55) min. Simple manual traction was sufficient to remove the lead in 59 (84%) patients, in whom lead-dwelling time was shorter [20 (9-32) months vs. 30 (22-41) months; P = 0.032]. Hospitalization time was short in the case of both non-infectious [2 (1-2) days] and infectious indications [3 (1-6) days]. In the case of infection, no patients required post-extraction intravenous antibiotics, the median duration of any antibiotic therapy was 10 (10-14) days, and the re-implantation was performed during the same procedure in 29% of cases. No complications arose over a median of 21 months.

CONCLUSION

The S-ICD extraction was safe and easy to perform, with no complications. Simple traction of the lead was successful in most patients, but specific tools could be needed for systems implanted for a longer time. The peri- and post-procedural management of S-ICD extraction was free from complications and not burdensome for patients and healthcare system.

CLINICAL TRIAL REGISTRATION

URL: http://clinicaltrials.gov/Identifier: NCT02275637.

Implantation of Implantable Cardioverter Defibrillators in Kazakhstan

Background and Objectives:

Implantation of implantable cardioverter-defibrillators (ICD) has increased significantly over the past decade. However, limited data exist regarding practices and policies of ICD implantations in Kazakhstan. We aimed to provide an overview of the current use of ICD in Kazakhstan.

Methods:

Using the Unified Healthcare Information System database of the entire Kazakh adult population, statistical and cost data of ICD implantations in 2017–2019 were evaluated. Cardiologists and electrophysiologists working in cardio surgery centers and departments were asked to go through an online survey focused on subcutaneous-ICD (S-ICD) experience.

Results:

Implantation of traditional transvenous cardioverter-defibrillators for residents of Kazakhstan is fully reimbursed. A total of 2,263 ICD interventions (2,252 new implantations and 11 reimplantations) were performed across the country during the study period. According to the tariffs approved by the Ministry of Health, the reimbursement cost for one ICD case is about 14,061.80 US dollars. The survey showed that only two hospitals have implanted S-ICDs. Among the main reasons why S-ICD is not widely used in the country the following were named: lack of trained staff (61.1% of respondents); the cost of device and lack of reimbursement (38.7%); and lack of pacing function (27.8%).

Conclusion:

The number of ICD implantation in Kazakhstan is steadily continuing to grow, although, compared to developed countries, the implantation rate especially for S-ICD remains low. There is a need in deliberate strategies to remove policy barriers for implementation the most innovative cardiac implantable electronic devices implantations such as S-ICD in the country.

Subcutaneous implantable cardioverter defibrillator: Can it overtake its transvenous counterpart

Over the past decade, the emergence of the subcutaneous implantable cardioverter defibrillator (S-ICD) has provided cardiologists with an option to provide both primary or secondary prevention treatment of sudden cardiac death (SCD) without the associated risks that come with the use of intracardiac leads. S-ICD may prove to be a useful option in those who are young, have thromboembolic risk, immunodeficiency states, unfavorable anatomy due to adult congenital heart disease (ACHD). This article reviews the existing literature to determine whether S-ICD can prove to be a safe alternative in comparison to Transvenous implantable cardioverter defibrillator (TV-ICD) and in which patient population should S-ICD be considered over TV-ICD.

What Promotes Surgeon Practice Change? A Scoping Review of Innovation Adoption in Surgical Practice

OBJECTIVE

The goal of this scoping review was to summarize the literature on facilitators and barriers to surgical practice change. This information can inform research to implement best practices and evaluate new surgical innovations.

BACKGROUND

In an era of accelerated innovations, surgeons face the difficult decision to either acknowledge and implement or forgo new advances. Although changing surgical practice to align with evidence is an imperative of health systems, evidence-based guidelines have not translated into consistent change. The literature on practice change is limited and has largely focused on synthesizing information on methods and trials to evaluate innovative surgical interventions. No reviews to date have grounded their analysis within an implementation science framework.

METHODS

A systematic review of the literature on surgical practice change was performed. Abstracts and full-text articles were reviewed for relevance using inclusion and exclusion criteria and data were extracted from each article. Cited facilitators and barriers were then mapped across domains within the implementation science Theoretical Domains Framework and expanded to the Capability, Opportunity, Motivation, and Behavior model.

RESULTS

Components of the Capability, Opportunity, Motivation, and Behavior model were represented across the Theoretical Domains Framework domains and acted as both facilitators and barriers to practice change depending on the circumstances. Domains that most affected surgical practice change, in order, were: opportunity (environmental context and resources and social influences), capability (knowledge and skills), and motivation (beliefs about consequences and reinforcement).

CONCLUSIONS

Practice change is predicated on a conducive environment with adequate resources, but once that is established, the surgeon's individual characteristics, including skills, motivation, and reinforcement determine the likelihood of successful change. Deficiencies in the literature underscore the need for further study of resource interventions and the role of surgical team dynamics in the adoption of innovation. A better understanding of these areas is needed to optimize our ability to disseminate and implement best practices in surgery.

Subcutaneous implantable cardioverter defibrillator indication in prevention of sudden cardiac death in difficult clinical situations: A French expert position paper

The introduction of a new technology always raises questions about its place compared with the reference technology. The use of an implantable cardioverter defibrillator to prevent sudden cardiac death is now a widely proven technique, with a clear statement of its indication in the guidelines. More recently, a subcutaneous implantable cardioverter defibrillator has been introduced, and appears to be an attractive technique as it removes the need to implant a lead inside the right ventricle to treat the patient, which should dramatically decrease the risk of complications over time. Currently, only one model of subcutaneous implantable cardioverter defibrillator is available on the market; its indications are the same as for transvenous implantable cardioverter defibrillators, except for patients who need stimulation because of conduction disorders or ventricular tachycardias that can potentially be treated effectively by antitachycardia pacing. The different technical characteristics of transvenous versus subcutaneous implantable cardioverter defibrillators therefore raise the question of which to choose in different clinical settings. The experts who participated in the preparation of this manuscript had three meetings, organized by the company Boston Scientific. Each expert prepared the draft of a section corresponding to a clinical situation. The choice between transvenous versus subcutaneous implantable cardioverter defibrillator was then voted on by all the experts. The results of the votes are presented in this manuscript, as it seemed important to us to show the disparities of opinion that can exist in certain situations. The votes were cast independently and anonymously.

Multicentre early experience with totally subcutaneous cardioverter-defibrillators in Poland

INTRODUCTION

Implantable cardioverter-defibrillators (ICD) have a strong position in the prevention of sudden death. Nowadays, the most commonly used high-energy cardiac devices are transvenous ICDs. A new technology of totally subcutaneous ICDs (S-ICD) was invented and recently introduced into clinical practice in order to reduce lead-related complications of conventional ICDs. The aim of this paper is to present early experience with this new technology implemented in a few centres in Poland.

MATERIAL AND METHODS

Medical records of patients who had S-ICD-related interventions in Poland were retrospectively analysed.

RESULTS

During the first year of S-ICD introduction into the Polish health system 18 patients underwent surgery connected with S-ICDs. Majority of them (17 patients) were implanted de novo. In one patient surgical revision of a device implanted abroad was performed. Most of patients (78%) had S-ICDs implanted for secondary prevention. Inability of transvenous system implantation due to venous access obstruction or high risk of infection related with transvenous leads accounted for 83% of indications for S-ICD. Only in three patients were S-ICDs implanted due to young age and active mode of life. The implantations of S-ICDs were performed without important early or late complications. During follow-up one patient had episodes of ventricular arrhythmia successfully terminated with high-energy shocks. One patient died due to progression of heart failure.

CONCLUSIONS

S-ICD implantation procedure has been successfully and safely introduced in Polish clinical routine. Nevertheless, despite clear indications in recent ESC guidelines, this therapy is not directly reimbursed in Poland and needs individual application for refund.

Leakage current from transvenous and subcutaneous implantable cardioverter defibrillators (ICDs): A risk to the rescuer?

BACKGROUND

Implantable cardioverter-defibrillators (ICDs) are a well-established therapy for patients at risk of life-threatening ventricular arrhythmias. With rising implant rates, the risk of a rescuer performing chest compressions during discharge is increasing, leading to concerns over rescuer safety from the resultant leakage current. More recently, subcutaneous ICDs (S-ICD) have been developed, which utilise a higher energy and more superficial electrodes compared with transvenous ICDs (T-ICD), raising safety concerns further.

OBJECTIVE

We measured the current a rescuer would potentially receive from T-ICDs and S-ICDs if they were in contact with the patient at the time of ICD discharge to assess its magnitude in relation to international safety standards.

METHODS

Surface voltages adjacent to ICD electrodes were measured on patients undergoing defibrillation threshold checks. Rescuer current was then calculated assuming a total rescuer circuit impedance of 1696 Ω.

RESULTS

Twenty-five patients were recruited. Rescuer current from S-ICDs was significantly higher than those from T-ICDs (S-ICD: Median RMS 135 mA range 91 mA-164 mA, T-ICD: Median RMS 31 mA, range 9 mA-75 mA, P < 0.0001). Surface voltages (median RMS) to which the rescuer is likely to be exposed are higher when performing chest compressions from the patient's left side compared with the right (127 V vs 67 V respectively, 95% CI of difference -34 V to -67 V, P < 0.0001).

CONCLUSIONS

Rescuers performing chest compressions on ICD patients are at risk from leakage current, particularly from S-ICDs. Chest compressions should be performed from the opposite side to the ICD to reduce rescuer risk.

Duration of hospital admission, need of on-demand analgesia and other peri-procedural and short-term outcomes in sub-cutaneous vs. transvenous implantable cardioverter-defibrillators

BACKGROUND

Post-procedural recovery following sub-cutaneous ICD (S-ICD) implantation is feared to be more painful and to require more prolonged hospital admission. The purpose of this study was to compare peri-procedural and short clinical outcomes of the S-ICD vs. the Transvenous ICD (TV-ICD).

METHODS

We conducted a single-center cross-sectional study including all consecutive patients who underwent S-ICD implantation by the same operator since January 2016 and a gender and age-matched control group with all single chamber TV-ICD implanted patients over a contemporary time period.

RESULTS

Thirty-one patients (sex ratio 1/5; mean age 58.7±13.2years) with S-ICD were compared to 31 matched TV-ICD patients. Duration of the implant procedure was significantly longer for the S-ICD (58.0±24.4min vs 41.7±20.8min TV-ICD, p<0.01). Mean fluoroscopy time for the TV-ICD was 3.5±3.6min vs 0.1±0.01min for all S-ICD patients (p<0.01). Requirement of on-demand analgesia administration, and duration of hospitalization (1.5days for both groups; p=NS) were similar in the two groups. No peri-procedural events were reported, and after a mean follow-up of 6months, the only complication was a pocket infection requiring reintervention in the TV-ICD group.

CONCLUSIONS

The S-ICD appears to be as effective and safe as the conventional single chamber TV-ICD. Duration of hospital admission and need of on-demand analgesia are also comparable for S-ICD patients.

The Italian subcutaneous implantable cardioverter-defibrillator survey: S-ICD, why not?

Aims

A recommendation for a subcutaneous-implantable cardioverter-defibrillator (S-ICD) has been added to recent European Society of Cardiology Guidelines. However, the S-ICD is not ideally suitable for patients who need pacing. The aim of this survey was to analyse the current practice of ICD implantation and to evaluate the actual suitability of S-ICD.

Methods and results

The survey ‘S-ICD Why Not?’ was an independent initiative taken by the Italian Heart Rhythm Society (AIAC). Clinical characteristics, selection criteria, and factors guiding the choice of ICD type were collected in consecutive patients who underwent ICD implantation in 33 Italian centres from September to December 2015. A cardiac resynchronization therapy (CRT) device was implanted in 39% (369 of 947) of patients undergoing de novo ICD implantation. An S-ICD was implanted in 12% of patients with no CRT indication (62 of 510 with available data). S-ICD patients were younger than patients who received transvenous ICD, more often had channelopathies, and more frequently received their device for secondary prevention of sudden death. More frequently, the clinical reason for preferring a transvenous ICD over an S-ICD was the need for pacing (45%) or for antitachycardia pacing (36%). Nonetheless, only 7% of patients fulfilled conditions for recommending permanent pacing, and 4% of patients had a history of monomorphic ventricular tachycardia that might have been treatable with antitachycardia pacing.

Conclusion

The vast majority of patients needing ICD therapy are suitable candidates for S-ICD implantation. Nevertheless, it currently seems to be preferentially adopted for secondary prevention of sudden death in young patients with channelopathies.

Initial experience with the subcutaneous implantable cardioverter-defibrillator with the real costs of hospitalization analysis in a single Polish center

BACKGROUND

The recent introduction of an entirely subcutaneous implantable cardioverter-defibril-lator (S-ICD) represents an important progress in the defibrillation technology towards a less invasive approach. This is a single-center observational study of S-ICD implantations in Poland.

METHODS

The S-ICD was implanted in 11 patients with standard indications for an ICD. Patients in whom the device was implanted were evaluated for adverse events and device function at hospital discharge. All hospitalization costs were calculated and summed up for all patients. Costs were divided into following categories: medical materials, pharmaceuticals, operating theatre staff, cardiology depart-ment staff, laboratory tests, non-laboratory tests and additional non-medical costs.

RESULTS

The mean age of patients was 51.6 ± 16.4 years, 9 were men and 2 were women. Four pa-tients had atrial fibrillation as the basal rhythm, 1 patient had atrial flutter and 6 patients had sinus rhythm. All patients had at least one condition that precluded the use of a traditional ICD system or the S-ICD was preferred due to other conditions, i.e. a history complicated transvenous ICD therapy (18%), anticipated higher risk of infection (27%), lack or difficult vascular access (18%), young age and anticipated high cumulated risk of lifetime device therapy (36%). The mean duration of the im-plantation procedure was 2 h. One patient developed a postoperative pocket hematoma. Mean total time of hospitalization was 28 (6-92) days. Average cost of hospitalization per patient was 21,014.29 EUR (minimal = 19,332.71 EUR and maximal = 24,824.14 EUR).

CONCLUSIONS

S-ICD implantation appears to provide a viable alternative to transvenous ICD, espe-cially for patients without pacing requirements.

[Management of inappropriate shocks/T-wave-oversensing in S-ICD®-patients]

Inappropriate shocks are a feared complication after implantable cardioverter-defibrillator (ICD) implantation and have a tremendous impact on quality of life. Inappropriate shocks in patients with subcutaneous ICD (S-ICD®, Boston Scientific, Marlborough, MA, USA) have various underlying causes. This review summarizes the current literature on this topic and lists possible treatment options.