S-ICD Implantation "Tips and Tricks".

An implantable cardioverter-defibrillator (ICD) was developed to provide protection against sudden cardiac death. Despite being effective in terminating ventricular arrhythmias, traditional transvenous ICDs appeared over time to have certain limitations related to the need for vascular access and the presence of foreign material inside the circulatory system (namely lead failure and infections). A subcutaneous implantable cardioverter-defibrillator (S-ICD) was developed to overcome those limitations and to provide prevention against sudden cardiac death from outside the cardiovascular system. Utilization of that modern method of treatment is constantly increasing worldwide, and new centers incorporate implantation of that system in their portfolio. This review aims to present the most relevant issues related to S-ICD implantation procedure, based on experience of the authors and an extensive literature search.

How likely is the sense-B-noise to affect patients with subcutaneous implantable cardioverter-defibrillators and can we solve that problem in every case?

BACKGROUND: Sense-B-noise is a newly reported possible cause of inappropriate shocks in patients with subcutaneous implantable cardioverter-defibrillators (S-ICDs). The nature of that noise is unknown, it is not related to mechanical failure of the S-ICD system. Reprogramming to the secondary sensing vector is suggested by the producer as a possible solution. METHODS: We analyzed the medical records of S-ICD recipients from two university clinical centers (Gdansk and Szczecin, Poland). Our aim was to determine the rate of sense-B-noise, and whether the secondary sensing vector would be available for reprogramming if such a problem occurred in our patients. RESULTS: The sense-B-noise issue affected three patients in our cohort (3%), which corresponds to the incidence of 0.012 events per patient-year of follow-up. The primary vector was permanently used in 47 patients (52%), secondary in 28 (31%), and alternate in 16 (17%), respectively. Therefore, the total number of patients potentially vulnerable to sense-B noise (with the primary or alternate vector programmed permanently) was 63 (69%). Among those 63 patients, 51 individuals (81%) had also the secondary vector available for permanent use. CONCLUSION: The sense-B-noise affected 3% of patients in our cohort, with an incidence of 0.012 per patient-year of follow-up. Most patients potentially vulnerable to sense-B noise could be reprogrammed to the secondary sensing vector, if necessary. Further investigation of the sense-B-noise issue is needed.

Comparison of Preoperative ECG Screening and Device-Based Vector Analysis in Patients Receiving a Subcutaneous Implantable Cardioverter-Defibrillator.

Background and Objectives: Subcutaneous implantable cardioverter-defibrillators (S-ICDs) provide protection against sudden cardiac death from outside the cardiovascular system. ECG screening is a prerequisite for implantation, but the reproducibility of its results post-operatively in the device is only partial. We aimed to compare the results of ECG screening with device-based sensing vector analysis. Materials and Methods: We screened the hospital records of all S-ICD recipients in our clinic. All of them had pre-operative ECG screening performed (primary, secondary, and alternate vectors). The results were compared with device-based vector analysis to determine the relation of the pre- and post-operative vector availability. Results: Complete ECG screening and device-based vector analysis were obtained for 103 patients. At least two acceptable vectors were found in 97.1% of the patients pre-operatively and in 96.1% post-operatively. When comparing vectors in terms of agreement (OK or FAIL) pre- and post-operatively, in 89.3% of the patients, the result for the primary vector was the same in both situations; for the secondary, it was in 84.5%, and for the alternate, it was in 74.8% of patients, respectively. In 55.3% of patients, all three vectors were labeled the same (OK or FAIL); in 37.9%, two vectors had the same result, and in 6.8%, only one vector had the same result pre- and post-operatively. The number of available vectors was the same pre- and post-operatively in 62.1% of patients, while in 15.5%, it was lower, and in 22.3% of patients, it was higher than observed during screening. Conclusions: Routine clinical pre-operative screening allowed for a good selection of candidates for S-ICD implantation. All patients had at least one vector available post-operatively. The final number of vectors available in the device-based analysis in most patients was at least the same (or higher) than during screening. The repeatability of the positive result for a single vector was high.

Implantation of a dual-chamber pacemaker with epicardial leads in adults using a minimally invasive subxyphoid approach.

BACKGROUND: Implantation of transvenous pacemaker systems is a standard method used to treat patients with bradycardia. There are some clinical settings in which that method cannot be used despite existing indications (such as developmental defects of the cardiovascular system and limited venous access or infections). In such cases, an epicardial pacing system may be implanted with cardiac surgery techniques, at a cost of certain surgical risks. The least invasive approach is subxyphoid, but it traditionally allows to place only a ventricular lead and achieve a single-chamber VVI pacing system. AIM: The aim of our study was to determine the feasibility of subxyphoid implantation of dual-chamber pacing systems using thoracoscopic tools, as well as to and examine the short- and mid-term outcomes of such procedures. METHODS: Patients were qualified for an epicardial pacemaker system in case of absolute indications for permanent pacing therapy and coexisting contraindications for a transvenous system. DDD systems were implanted in 10 consecutive patients, in general anesthesia, in a cardiac surgery operating room, using subxyphoid access to pericardial space and a standard set of minimally invasive thoracoscopic tools. RESULTS: Implantation of a dual-chamber pacing system using the above approach was successful in all attempts. No serious complications were observed. Pacing and sensing parameters were appropriate at implantation and remained such during the follow-up of 2-27 months. CONCLUSION: Implantation of a dual-chamber pacing system using a minimally invasive subxyphoid approach is feasible. Appropriate pacing and sensing values may be obtained and they remain stable during follow-up.

A survey study of the use of a subcutaneous implantable cardioverter-defibrillator in various clinical scenarios by expert electrophysiologists in Poland.

BACKGROUND: A subcutaneous implantable cardioverter-defibrillator (S-ICD) has become a recognized alternative to a traditional transvenous implantable cardioverter-defibrillator (T-ICD). Despite the growing evidence of non-inferiority of S-ICD, there are no clear clinical guidelines for selection of either of the two available systems. The aim of the study was to analyze the decisions made in predefined typical clinical scenarios by Polish cardiologists experienced in the use of both S-ICDs and T-ICDs. METHODS: A group of 30 experts of cardiac electrotherapy experienced in the use of S-ICDs was recruited and invited to participate in a web-based anonymous survey. The survey questions regarded the proposed therapy in various but typical clinical scenarios. RESULTS: From the invited 30 experts representing 18 clinical centers, 25 completed the survey. 72% of them declared that the number of S-ICDs implanted at their center during the preceding 12 months exceeded 10, and 40% - that it was over 20. Rates of responders preferring S-ICD or T-ICD in various clinical scenarios are reported and discussed in detail. CONCLUSIONS: Significant divergence of opinion exists among Polish experts regarding the use of a subcutaneous cardioverter-defibrillator. It is especially pronounced on the issue of the use of the system in middle-age patients, in case of complications of the hitherto ICD therapy, or the need of upgrading the existing cardiac implantable electronic device.

Application of Novel Technologies in Cardiac Electrotherapy to Prevent Complications.

(1) Background: Cardiac electrotherapy is developing quickly, which implies that it will face a higher number of complications, with cardiac device-related infective endocarditis (CDRIE) being the most frequent, but not the only one. (2) Methods: This is a retrospective case study followed by a literature review, which presents a patient with a rare but dangerous complication of electrotherapy, which could have been prevented if modern technology had been used. (3) Results: A 34-year-old female was admitted with suspicion of CDRIE based on an unclear echocardiographic presentation. However, with no signs of infection, that diagnosis was not confirmed, though an endocardial implantable cardioverter-defibrillator (ICD) lead was found folded into the pulmonary trunk. The final treatment included transvenous lead extraction (TLE) and subcutaneous ICD (S-ICD) implantation. (4) Conclusions: With the increasing number of implantations of cardiac electronic devices and their consequences, a high index of suspicion among clinicians is required. The entity of the clinical picture must be thoroughly considered, and various diagnostic tools should be applied. Lead dislocation into the pulmonary trunk is an extremely rare complication. Our findings align with the available literature data, where asymptomatic cases are usually effectively treated with TLE. Modern technologies, such as S-ICD, can effectively prevent lead-related problems and are indicated in young patients necessitating long-term ICD therapy.

Subcutaneous implantable cardioverter-defibrillator therapy in Poland: Results of the Polish S-ICD Registry.

BACKGROUND: The use of subcutaneous implantable cardioverter-defibrillators (S-ICD) has been growing in Poland since 2014. The Polish Registry of S-ICD Implantations was run by the Heart Rhythm Section of the Polish Cardiac Society between May 2020 and September 2022 to monitor the implementation of that therapy in Poland. AIMS: To investigate and present the state-of-the-art of S-ICD implantation in Poland. METHODS: Implanting centers reported clinical data of patients undergoing S-ICD implantations and replacements, including age, sex, height, weight, underlying disease, history of pacemaker and defibrillator implantations, indications for S-ICD, electrocardiographical parameters, procedural techniques, and complications. RESULTS: Four hundred and forty patients undergoing S-ICD implantation (411) or replacement (29) were reported by 16 centers. Most patients were in New York Heart Association class II (218 patients, 53%) or I (150 patients, 36.5%). Left ventricular ejection fraction was 10%-80%, median (IQR) was 33% (25%-55%). Primary prevention indications were present in 273 patients (66.4%). Non-ischemic cardiomyopathy was reported in 194 patients (47.2%). The main reason for the choice of S-ICD were: young age (309, 75.2%), risk of infectious complications (46, 11.2%), prior infective endocarditis (36, 8.8%), hemodialysis (23, 5.6%), and immunosuppressive therapy (7, 1.7%). Electrocardiographic screening was performed in 90% of patients. The rate of adverse events was low (1.7%). No surgical complications were observed.

Eligibility of patients with temporary paced rhythm for a subcutaneous implantable cardioverter-defibrillator.

BACKGROUND: A concomitant use of a pacemaker and a subcutaneous implantable cardioverter-de-fibrillator (S-ICD) may be required in some patients. AIMS: Our study aimed to evaluate the influence of permanent cardiac pacing on the morphology of the QRS complex in the context of S-ICD screening. METHODS: One hundred patients with cardiac electronic implantable devices (CIEDs) were included in whom S-ICD screening could be performed both during intrinsic and paced rhythm. RESULTS: The positive result of screening during spontaneous rhythm for at least one vector (in both supine and standing positions) was obtained in 80% and for 2 vectors in 59% of patients. Positive screening during paced rhythm for at least one vector was recorded in 36% of patients (78% right ventricular and 22% biventricular pacing) and for 2 vectors in 15% of patients (93% right ventricular and 7% biventricular pacing). At least one vector acceptable during both types of rhythm and in both positions was recorded in 23% of patients and at least 2 vectors in 8% of patients. CONCLUSIONS: The use of S-ICD in patients with paced ventricular rhythm is associated with a serious risk of inappropriate sensing due to different QRS morphology during intrinsic and paced rhythm, and it is particularly high in patients in whom periods of spontaneous rhythm interchange with periods of ventricular pacing. That risk has been hardly acknowledged in available reports, but according to our data, it is significant, and therefore it should be considered during S-ICD screening.

Real-Life Inter-Rater Variability of the PRAETORIAN Score Values.

(1) Background: The PRAETORIAN score is a tool developed for postoperative evaluation of the position of subcutaneous implantable cardioverter-defibrillator systems. The aim of our study was to evaluate the real-life inter-rater variability of the PRAETORIAN score, based on chest radiographs of S-ICD patients reviewed by independent clinical raters. (2) Methods: Postoperative chest X-rays of patients that underwent S-ICD implantation were evaluated by five clinical raters who gave values of the PRAETORIAN score. Ratings were then compared in a fully crossed manner to determine the inter-rater variability of the attributed scores. (3) Results: In total, 87 patients were included in the study. In the case of the most important final risk category of the PRAETORIAN score, the mean Light's kappa was 0.804, the Fleiss' kappa was 0.249, and the intraclass correlation was 0.38. The final risk category was identically determined by all five raters in 75.86% of patients, by four raters in 14.94%, and by three raters in 9.20% of patients. (4) Conclusions: The overall inter-rater variability of the PRAETORIAN score in a group of electrophysiologists experienced in S-ICD implantation, yet previously naive to the PRAETORIAN score, and self-trained in its utilization, was only modest in our study. Appropriate use of the score might require training of clinical raters.

Utilization of Subcutaneous Cardioverter-Defibrillator in Poland and Europe-Comparison of the Results of Multi-Center Registries.

The implantation of a subcutaneous cardioverter-defibrillator (S-ICD) may be used instead of a traditional transvenous system to prevent sudden cardiac death. Our aim was to compare the characteristics of S-ICD patients from the multi-center registry of S-ICD implantations in Poland with the published results of the European Snapshot Survey on S-ICD Implantation (ESSS-SICDI). We compared data of 137 Polish S-ICD patients with 68 patients from the ESSS-SICDI registry. The groups did not differ significantly in terms of sex, prevalence of ischemic cardiomyopathy, concomitant diseases, and the rate of primary prevention indication. Polish patients had more advanced heart failure (New York Heart Association (NYHA) class III: 11.7% vs. 2.9%, NYHA II: 48.9% vs. 29.4%, NYHA I: 39.4% vs. 67.7%, p < 0.05 each). Young age (75.9% vs. 50%, p < 0.05) and no vascular access (7.3% vs. 0%, p < 0.05) were more often indications for S-ICD. The percentage of patients after transvenous system removal due to infections was significantly higher in the Polish group (11% vs. 1.5%, p < 0.05). In the European population, S-ICD was more frequently chosen because of patients' active lifestyle and patients' preference (both 10.3% vs. 0%, p < 0.05). Our analysis shows that in Poland, compared to other European countries, subcutaneous cardioverters-defibrillators are being implanted in patients at a more advanced stage of chronic heart failure. The most frequent reason for choosing a subcutaneous system instead of a transvenous ICD is the young age of a patient.

Long-term follow-up of implantable cardioverter-defibrillators in children: Indications and outcomes.

BACKGROUND: Validation data of the use of implantable cardioverter-defibrillators (ICD) in the pediatric population is insufficient, with limited follow-up periods. OBJECTIVES: The aim of the study was to report on 17 years of experience with implantable cardioverter-defibrillator (ICD) therapy in children and young adults. MATERIAL AND METHODS: This retrospective review included patients below the age of 18 years at the time of ICD implantation between May 2000 and December 2017. For the statistical analysis, the sample was divided into groups by gender and the type of indications for ICD implantation (primary vs secondary prevention). RESULTS: The study group included 20 children (8 female, 12 male) who underwent ICD implantation for primary or secondary prevention of sudden cardiac death (SCD). The average age at the time of the initial procedure was 15.6 years (range: 3.8-17.7 years). Primary electrical disease (PED) was present in 9 patients, cardiomyopathy (CMP) in 9 and 2 others had congenital heart defects (CHDs). The median follow-up time was 6.7 years (range: 0.4-12.5 years). The outcomes of ICD therapy were analyzed. No differences between the sexes were found in terms of treatment strategy effectiveness (p > 0.05). The girls were more often treated as primary prevention (p = 0.009). After implantation, all the patients were on optimal pharmacotherapy. Alltogether there were 126 ICD interventions in 11 patients, including 23 inadequate interventions (IA) in 2 children (18.2%).Three children (15%) died due to electrical storms. In the per-procedure analysis, the overall freedom rate from ICD lead replacement was 90%, 80% and 57% at 1, 5 and 10 years of observation, respectively. CONCLUSIONS: Implantable cardioverter-defibrillator implantation indications in children are more heterogeneous in comparison to adult population. In the pediatric population undergoing ICD implantation, the treatment strategy is influenced by gender. The rate of inappropriate ICD discharges (IA) in our group of pediatric patients was low. Rigorous pharmacotherapy and individual ICD programming seemed of paramount importance. Lead malfunctions LF constituted the most prevalent complication observed.

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.

Infections of cardiac implantable electronic devices: Epidemiology, classification, treatment, and prognosis.

The increasing number of implantation procedures of implantable cardiac electronic devices (ICEDs) leads to a substantial growth of a cohort of patients in whom complications of such a therapy occur. Infective complications are among the most severe ones, as they are often associated with poor prognosis. Depending on the criteria applied, the incidence of cardiac device infection (CDI) is estimated at 0.5-2.2%. Many risk factors of CDIs have been identified, among which the most important are numerous previous cardiac electrotherapy procedures and their complexity, and the lack of perioperative antibiotic prophylaxis. Appropriate diagnosis of a suspected CDI is of utmost importance, as well as the correct classification of the infection, which leads to adequate treatment. Management of a CDI should include complete removal of the implanted device. Additionally, empirical and then targeted antibiotic therapy should be instituted. The prognosis of CDI may, nonetheless, be unfavorable. Despite appropriate treatment, the total mortality rate of such complication is estimated to be as high as 35%.

Polish single-centre follow-up of subcutaneous implantable cardioverter-defibrillator (S-ICD) systems implanted for the prevention of sudden cardiac death.

BACKGROUND AND AIM: Subcutaneous implantable cardioverter-defibrillator (S-ICD) is an effective and modern tool used to protect patients at risk of sudden cardiac death (SCD) from potentially life-threatening ventricular arrhythmias. The first S-ICD systems were implanted in Poland in 2014, but since that time the national experience with that therapy has been limited. Our analysis summarises the single-centre experience at the Department of Cardiology and Electrotherapy of the Medical University of Gdansk with the use of S-ICD from the year 2014 to 2017. METHODS AND RESULTS: The S-ICD therapy was used in 12 patients (five male, seven female, mean age 57.2 ± 12.5 years), in eight of them for the secondary prevention of SCD. No surgical complications of implantation procedures were observed during the perioperative hospitalisation nor during follow-up. During the mean follow-up of 14 ± 13 months we observed the appropriate function of the systems and a ventricular fibrillation episode successfully terminated by the device in one patient, two cases of S-ICD sensing problems (one of which led to inadequate intervention of the device), and an episode of atrial fibrillation also leading to inadequate intervention in another patient. CONCLUSIONS: S-ICD, being an effective and safe method used to treat patients at risk of SCD, may be safely and successfully introduced into clinical practice in centres new to that field. The number of complications during the initial experience and introduction of that method may be kept low if the operating team is experienced enough in cardiac electrotherapy.