Occurrence Of Inappropriate Shocks Research Articles

Equal performance of the subcutaneous and transvenous implantable cardioverter defibrillator across all age groups in the PRAETORIAN trial

Abstract Introduction The subcutaneous ICD (S-ICD) is developed to overcome lead-related complications and systemic infections, inherent to transvenous ICD (TV-ICD) therapy. In the PRAETORIAN trial the S-ICD proved to be non-inferior to the TV-ICD with regard to inappropriate shocks (IAS) and complications. However, the S-ICD is still mainly the preferred choice in young patients with a long life expectancy and therefore higher risk for lead-related complications. We aimed to evaluate the impact of age on complications and IAS between the S-ICD and TV-ICD. Methods The PRAETORIAN trial is an investigator-initiated, international, multicenter, randomized, two-arm noninferiority trial that was conducted in the United States and Europe. In total 849 patients with a class I or IIa indication for ICD therapy and no pacing indication were randomized to receive an S-ICD (N=426) or TV-ICD (N=423) and followed for a median of 49 months. We compare the occurrence of complications and IAS between increasing quartiles of age. Results Quartile 1 (Q1) consisted of 203 patients aged <55 (109 S-ICD, 94 TV-ICD), Q2 of 199 patients aged 55-62 (100 S-ICD, 99 TV-ICD), Q3 of 232 patients aged 63-69 (111 S-ICD, 121 TV-ICD) and Q4 of 215 patients aged ≥70 (106 S-ICD, 109 TV-ICD). Between the quartiles, there were no significant differences in occurrence of device-related complications (P = 0.32) or IAS (P = 0.66). In Q1, there were 15 (7.4%) complications (5 S-ICD, 10 TV-ICD) and 13 (6.4%) IAS (7 S-ICD, 6 TV-ICD), compared to 20 (10.1%) complications (7 S-ICD, 13 TV-ICD) and 17 (8.5%) IAS (9 S-ICD, 8 TV-ICD) in Q2, 22 (9.5%) complications (12 S-ICD, 10 TV-ICD) and 19 (8.2%) IAS (11 S-ICD, 8 TV-ICD) in Q3 and 18 (8.4%) complications (7 S-ICD, 11 TV-ICD) and 21 (9.8%) IAS (14 S-ICD, 7 TV-ICD) in Q4 (Figure 1.). Figure 2. shows forest plots of the hazard ratios per quartile. Conclusions The S-ICD performed equal to the TV-ICD with regard to IAS and complications between quartiles of age, making the S-ICD a good alternative across all age groups.

Intermuscular two-incision technique for implantation of the subcutaneous implantable defibrillator: 3-year follow-up

Abstract Funding Acknowledgements Type of funding sources: None. Background data on long-term outcome of the intermuscular (IM) two-incision implantation technique for the subcutaneous implantable cardioverted defibrillator (S-ICD) are lacking. Purpose the aim of the present study was to evaluate the outcome of patients underwent S-ICD implantation with the IM two-incision technique during 3-year follow-up. Methods the study population consisted of 105 consecutive patients (79 male; median 50 [13-77] years) underwent S-ICD implantation with the IM two-incision technique. Results according to the PRAETORIAN score, the risk of conversion failure was classified as low in 99 patients (94.3%), intermediate in 6 (5.7%).Ventricular fibrillation was successfully converted at ≤65 J in 97.4% of patients. During a median follow-up of 39 (16-53) months, 10 patients (9.5%) experienced device-related complications and 9 (8.5%) patients reported inappropriate shocks (IAS). Lead-associated complications were the most common (4.7%), including 2 cases of lead failure (1.9%). Pocket complications were reported in 2 patients (1.9%). Extra-cardiac oversensing (3.8%) represented the leading cause of IAS. No T-wave oversensing episodes were recorded. Twelve patients (11.4%) experienced appropriate shocks. Eight patients (7.6%) died during follow-up. IAS or device-related complications did not impact on mortality (HR 0.5; 95%CI 0-4.3; P=0.5; HR 0.7; 95%CI 0.1-6.0; P=0.8, respectively). Conclusions according to our findings, the IM two-incision technique allows for optimal positioning of the device achieving a low PRAETORIAN score with a high conversion rate. IM two-incision technique allows low incidence of pocket complications, shifting the type of complications towards lead-related complications, which represent the most common complications. The IM two-incision technique would not seem to impact the occurrence of IAS. Management of complications are safe without impact on the outcome.

P8 INTERMUSCULAR TWO–INCISION TECHNIQUE FOR IMPLANTATION OF THE SUBCUTANEOUS IMPLANTABLE CARDIOVERTER DEFIBRILLATOR: 3–YEAR FOLLOW–UP

Abstract Purpose The aim of the present study was to evaluate the outcome of patients underwent subcutaneous implantable cardioverter defibrillator (S–ICD) implantation with the intermuscular (IM) two-incision technique during 3–year followup. Methods The study population consisted of 105 consecutive patients (79 male; median 50 [13-77] years) underwent S–ICD implantation with the IM two-incision technique. The composite primary end point of the study consisted of device–related complications and inappropriate shocks (IAS). Secondary end points included the individual components of the primary end point, death from any cause, appropriate therapy, major adverse cardiac events, hospitalization for heart failure, heart transplantation. Results According to the PRAETORIAN score, the risk of conversion failure was classified as low in 99 patients (94.3%), intermediate in 6 (5.7%).Ventricular fibrillation was successfully converted at ≤65 J in 97.4% of patients. During a median follow–up of 39 (16–53) months, 10 patients (9.5%) experienced device–related complications and 9 (8.5%) patients reported inappropriate shocks (IAS). Leadassociated complications were the most common (5 patients, 4.7%), including 2 cases of lead failure (1.9%). Pocket complications were reported in 2 patients (1.9%). Extra–cardiac oversensing (3.8%) represented the leading cause of IAS. No T–wave oversensing episodes were recorded. Twelve patients (11.4%) experienced appropriate shocks. Eight patients (7.6%) died during follow–up. IAS or device–related complications did not impact on mortality. Conclusions The overall device–related complications and IAS rates over 3 years of follow–up were 9.5% and 8.5%, respectively. According to our findings, the IM two–incision technique allows for optimal positioning of the device achieving a low PRAETORIAN score with a high conversion rate. IM two–incision technique allows low incidence of pocket complications, shifting the type of complications towards lead–related complications, which represent the most common complications. The IM two–incision technique would not seem to impact the occurrence of IAS. Management of complications are safe without impact on the outcome.

Comparison of defibrillation modalities in the paediatric population: IChildren registry, a French observational and multicentric study

The presence of an implantable cardioverter-defibrillator (ICD) in the paediatric population is marked by the occurrence of more frequent complications compared to the adult population, such as lead failure, infections and inappropriate shocks. The objectives of the iChildren study is to carry out an inventory of French practices and to compare the three available defibrillation methods (endovascular, surgical, subcutaneous S-ICD) in terms of effectiveness and safety. We retrospectively included 274 children aged 16 years or younger at the time of the first implantation of an ICD, from most of the major French implanting centres since 2005. Data were collected in an eCRF. The primary composite outcome (PCO) associates the occurrence of lead failure or device infection. We also analyse the rate of appropriate and inappropriate shocks. An endovascular ICD was implanted in 103 patients (38%), a subcutaneous ICD (S-ICD) in 55 patients (20%), a surgical ICD in 116 patients (42%). During a mean follow-up time of 5.7 years, the occurrence of PCO was found in 21% of patients, 5% of the S-ICD patients, 19% of the endovascular patients, 29% of the surgical patients. In univariate analysis, the factors associated with PCO were: young age group, type of ICD. In multivariate analysis, after adjustment, the surgical ICD was associated with the highest risk of PCO (P < 0.05). In the total population, the rate of appropriate shocks was 30%, the rate of inappropriate shocks was 11%, with no statistically significant difference between ICD types at implantation. Surgical implantation of an ICD is associated with more long-term complications, such as lead failure and device infection. There was no statistically significant difference in the occurrence of inappropriate shocks between the 3 defibrillation approaches.

Intermuscular two-incision technique for implantation of the subcutaneous implantable cardioverter defibrillator: a 3-year follow-up.

The aim of the present study was to evaluate the outcome of patients underwent subcutaneous implantable cardioverter defibrillator (S-ICD) implantation with the intermuscular (IM) two-incision technique during 3-year follow-up. the study population consisted of 105 consecutive patients (79 male; median 50 [13-77] years) underwent S-ICD implantation with the IM two-incision technique. The composite primary end point of the study consisted of device-related complications and inappropriate shocks (IAS). Secondary end points included the individual components of the primary end point, death from any cause, appropriate therapy, major adverse cardiac events, hospitalization for heart failure, and heart transplantation. According to the PRAETORIAN score, the risk of conversion failure was classified as low in 99 patients (94.3%), intermediate in 6 (5.7%).Ventricular fibrillation was successfully converted at ≤65 J in 97.4% of patients. During a median follow-up of 39 (16-53) months, 10 patients (9.5%) experienced device-related complications, and 9 (8.5%) patients reported IAS. Lead-associated complications were the most common (5 patients, 4.7%), including 2 cases of lead failure (1.9%). Pocket complications were reported in 2 patients (1.9%). Extra-cardiac oversensing (3.8%) represented the leading cause of IAS. No T-wave oversensing episodes were recorded. Twelve patients (11.4%) experienced appropriate shocks. Eight patients (7.6%) died during follow-up. IAS or device-related complications did not impact on mortality. The overall device-related complications and IAS rates over 3 years of follow-up were 9.5% and 8.5%, respectively. According to our findings, the IM two-incision technique allows for optimal positioning of the device achieving a low PRAETORIAN score with a high conversion rate. IM two-incision technique allows low incidence of pocket complications, shifting the type of complications towards lead-related complications, which represent the most common complications. The IM two-incision technique would not seem to impact the occurrence of IAS. Management of complications are safe without impact on the outcome.

Age-related differences and associated outcomes of S-ICD: insights from a large, european, multicenter, real-world registry

Abstract Funding Acknowledgements Type of funding sources: None. Background Young patients often represent the most suitable candidates for an entirely subcutaenous implantable cardioverter defibrillator (S-ICD) system, since they have to face a lifetime of device therapy and they rarely have a pre-existing or concurrent pacing or cardiac resynchronization therapy (CRT) indication. Moreover, S-ICD offers lower rate and a safer management of lead and major procedure-related complications. To date, a few limited case series and experiences with S-ICD in teenagers and young adults have shown that the S-ICD system is safe and feasible in this population, with a rate of inappropriate shocks (IS) comparable to transvenous (TV) ICD, but focused analysis on a large scale are currently lacking in this setting. Purpose The aim of the current study was to compare the age-related differences observed in patient selection, baseline characteristics, and device long-term associated outcomes in a large real world cohort of S-ICD recipients. The primary outcome of the study was defined as the comparisons of the IS rate observed during the entirety of follow up in the teenagers/young adult vs the adult populations. Rate of complications, freedom from sustained ventricular arrhythmic events, overall and cardiovascular mortality were also assessed in the two cohorts and assessed as secondary outcomes. Methods All S-ICD recipients in the ELISIR project were enrolled in the current study. Patients were classified into teenagers + young adults (≤ 30 years old) vs adults (&amp;gt; 30 years old), depending from patient age at device implantation (Figure 1). Rates of device-related complications and IS were compared between the cohorts. Results A total of 1349 patients were extracted from the ELISIR project. Teenagers and young adults represented 12.4% of the registry (n=56 teenagers; n=112 young adults). Patients were followed-up for a median of 23.1 [12.6–37.9] months. Overall, 117 (8.7%) patients experienced inappropriate S-ICD shocks and 100 (7.4%) device related complications were observed, with no age-related differences. IS resulted more frequent in the teenager and young adult cohort (14.3% vs 7.9%; p=0.006). Figure 2 reports Kaplan Meier curves for the occurrence of IS. At univariate analysis, young age was associated with IS, but after correcting for differences in arrhythmic substrate, this association resulted non-significant (aHR: 1.428 [0.883–2.331]; p=0.146). The use of SMART pass algorithm was instead associated to a strong reduction in IS (aHR 0.367 [0.245–0.548]; p&amp;lt;0.001). Conclusion The use of S-ICD in teenagers/young adults resulted safe and effective. Indeed, the rate of complications between teenagers/young adults and adults was not significantly different. Although a higher rate of IS was observed in the teenagers/young adults, when accounting for differences in baseline substrate and comorbidities, young age did not result associated with an increased risk of IS.

Factors associated with implantable cardioverter-defibrillator shocks in patients suffering from non-ischemic cardiomyopathy.

Although intra-cardiac shocks are a lifesaving approach in patients with systolic heart failure (HF), the probable effective factors related to shock occurrence are less frequently recognized. We designed this study to assess the factors associated with inappropriate or appropriate implantable cardioverter-defibrillator (ICD) shocks in patients with non-ischemic cardiomyopathy (NICM). Ninety-nine patients with NICM who implanted ICD were enrolled from March 2018 to September 2019 and followed up with a three-month interval for up to one year. Shock therapy was defined as either appropriate or inappropriate shock. The odds ratio (OR) of inappropriate shock occurrence was calculated with crude and different adjusted models. The mean age of the population at baseline was 51.9 ± 15.4 years (men: 71%). Baseline data revealed that patients with inappropriate shocks had higher heart rates (HR), worse New York Heart Association (NYHA) class, and anti-tachycardia pacing (ATP) as well as higher percentages of amiodarone usage compared to groups with appropriate or no shock [HR: 96.8 ± 27.8 vs. 79.8 ± 12.1 vs. 76.2 ± 17.6 beats per minute (bpm), P = 0.014; NYHA class IV: 85.7% vs. 74.1% vs. 63.4%, P = 0.041; ATP: 37.5% vs. 29% vs. 5%, P = 0.010; amiodarone usage: 37.5% vs. 25.8% vs. 5%, P = 0.23, respectively]. Further multiple-adjusted OR did not reveal any significant independent association between the aforementioned variables and inappropriate shock incidence. This study indicates no significant independent predisposing factor in the occurrence of inappropriate shocks among patients with NICM. Other studies are required in this regard.

Frequent Home Monitoring of ICD Is Effective to Prevent Inappropriate Defibrillator Shock Delivery.

Recently, in the context of telemedicine, telemonitoring services are gaining attention. They are offered, for example, to patients with implantable cardioverter defibrillators (ICDs). A major problem associated with ICD therapy is the occurrence of inappropriate shocks which impair patients' quality of life and may also be arrhythmogenic. The telemonitoring can provide a valid support to intensify followup visits, in order to improve the prevention of inappropriate defibrillator shock, thus enhancing patient safety. Inappropriate shock generally depends on atrial fibrillation, supraventricular tachycardia, and abnormal sensing (such as those caused by electromagnetic interferences). As a practical example, an unusual case of an ICD patient who risked an inappropriate shock while taking a shower is reported. Continuous remote telemonitoring was able to timely warn cardiologist via GSM-SMS, who were able to detect improper sensing examining the intracardiac electrogram via Web. Patient was promptly contacted and warned to not further come in contact with the hydraulic system and any electrical appliance to prevent an inappropriate defibrillator shock. This demonstrates the effectiveness and usefulness of continuous remote telemonitoring in supporting ICD patients.

Inappropriate Shocks in Patients with ICDs: Single Chamber versus Dual Chamber

BackgroundDespite the technological evolution of the implantable defibrillator, one of the questions that remains is the possible benefit of the dual chamber versus single chamber implantable cardioverter defibrillator (ICD) in reducing inappropriate shocks.ObjectiveTo evaluate which type of device provides fewer inappropriate shocks (dual chamber versus single chamber) in patients with implantable cardioverter defibrillators (ICDs).MethodsMeta-analysis of randomized studies published in the literature comparing dual-chamber implantable cardioverter defibrillators to single chamber devices which have been known to cause, as an evaluated endpoint, inappropriate shocks. ResultsThe dual-chamber implantable cardioverter showed no benefit in reducing the number of inappropriate shocks. In fact, the opposite was shown. In the analysis of fixed effects, the association tended to favor single-chamber implantable cardioverter defibrillators (OR = 1.53, CI 95%: 0.91-2.57), despite the absence of statistical significance (p = 0.11). We highlight the heterogeneity observed in the results (I2 = 53%), which motivated a replication of the analysis using a model of random effects. However, significant differences remained in the occurrence of inappropriate shocks in both groups (OR = 1.1, 95% CI: 0.37-3.31; p = 0.86). To complement the analysis, we proceeded to perform sensitivity analysis, which showed that the exclusion of a study resulted in the lowest heterogeneity observed (I2=24%) and the association with inappropriate shocks significantly favored the single chamber cardiodefibrillator (OR = 1.91; 95% CI: 1.09-3.37; p = 0.27).ConclusionsIt was determined that there was no clear evidence of superiority of any of the devices evaluated.

Tools and strategies for the reduction of inappropriate implantable cardioverter defibrillator shocks

Implantable cardioverter defibrillators (ICDs) have been shown to provide a survival benefit in patients at high risk of sudden cardiac death. A major problem associated with ICD therapy is the occurrence of inappropriate shocks which impair patients' quality of life and may also be arrhythmogenic. Despite recent technological advances, the incidence of inappropriate shocks remains high, thus posing a challenge that we have to meet. In the present review we summarise the available tools and the strategies that can be followed in order to reduce inappropriate ICD shocks.

Atrial fibrillation predicts appropriate shocks in primary prevention implantable cardioverter-defibrillator patients

Atrial fibrillation (AF) is often present in patients with left ventricular dysfunction who receive an implantable cardioverter-defibrillator (ICD). The purpose of this study was to investigate whether AF is associated with appropriate shocks and cardiovascular mortality in primary prevention ICD patients with left ventricular dysfunction. We included 80 primary prevention ICD patients with left ventricular dysfunction and compared the outcome between patients with a history of AF (n=29) and patients with no history of AF (n=51). The primary endpoint was occurrence of appropriate shocks. Secondary endpoints were: (1) the composite of cardiovascular mortality/appropriate shocks; and (2) inappropriate shocks. During follow-up (median 8 months, range 1-60), patients with a history of AF more often received appropriate shocks than patients with no history of AF (24 vs. 6%, P=0.03). The composite endpoint of cardiovascular mortality/appropriate shocks was also more likely to occur in patients with a history of AF (34 vs. 12%, P=0.02). History of AF predicted appropriate shocks (HR 6.9, 95% CI 1.7-27.5, P=0.006) and the composite endpoint of cardiovascular mortality/appropriate shocks (adjusted HR 5.1, 95% CI 1.7-15.1, P=0.003). There were no differences in occurrence of inappropriate shocks. Our study demonstrates that history of AF is associated with increased risk of appropriate shocks and cardiovascular mortality in primary prevention ICD patients with left ventricular dysfunction.