Defibrillator Patients Research Articles

Incidence of systolic heart failure and need for implantable cardiac defibrillators in patients with atrial fibrillation who had catheter ablation versus antiarrhythmic medical therapy

Abstract Background The CASTLE-AF trial demonstrated that patients with atrial fibrillation (AF) and heart failure with reduced ejection fraction (HFrEF) who underwent catheter ablation (CA) showed improved patient outcomes. These outcomes included a reduction in all-cause mortality and heart failure hospitalizations along with an improvement in left ventricular ejection fraction, when compared to those receiving medical therapy alone. However, there is no data regarding development of novel HFrEF and the need for implantable cardiac defibrillator (ICD) in patients with AF who underwent CA vs. those on antiarrhythmic therapy (AAD). Purpose This study aims to assess if there is a difference in the development of HFrEF and the need for ICD intervention amongst AF patients who underwent CA vs. those on AAD. We hypothesize that patients with AF who underwent CA will have a decrease in the development of HFrEF and mitigation in the need for ICD intervention compared to AAD alone. Methods A large retrospective, multicentre database was utilized to identify patients aged 18-80 with AF from 2017-2023. Two cohorts were subsequently established based on treatment received: 1) CA vs. 2) AAD (amiodarone, flecainide, dronedarone, dofetilide, propafenone, sotalol). Patients with crossover between the groups were excluded. Student’s t-test was performed to compare baseline characteristics between cohorts. Relevant comorbidities, atrial fibrillation types, and cardiovascular medications were used for propensity matching. Kaplan Meier curves were calculated to compare outcomes at 5 years such as HFrEF development, ICD implantation, mortality, and hospitalizations. Results Patients that underwent CA (n=32,774) and AAD (n=345,882) were propensity matched yielding 32,670 patients per cohort. CA demonstrated a significantly decreased need for ICD intervention compared to AAD (1.69% vs. 3.28%; HR=0.559; 95% CI [0.503, 0.621], log rank p<0.0001). Secondary outcomes showed significant reduction in development of systolic heart failure (4.83% vs. 10.60%; HR=0.499; 95% CI [0.467, 0.533], log rank p<0.0001), overall hospitalizations (12.03% vs. 27.32%; HR=0.440; 95% CI [0.420, 0.461], log rank p<0.0001), and all-cause mortality (2.38% vs. 14.19%; HR=0.188; 95% CI [0.174, 0.203], log rank p<0.0001) with catheter ablation. Conclusions Patients that underwent CA had a significant reduction in development of systolic heart failure and mitigation in the need for ICD implantation when compared to those on AAD alone. Randomized clinical trials are needed to better understand this relationship and to further define which subpopulation of atrial fibrillation patients would derive the most benefit from CA.

Optimizing patient selection for cardiac resynchronization therapy in a multicenter study of Japanese patients: assessment of the MADIT-ICD benefit group

Abstract Background The MADIT-ICD benefit group, derived from ventricular tachycardia (VT)/ventricular fibrillation (VF) scores and non-arrhythmic mortality scores (Table 1), facilitates the appropriate selection of candidates for implantable cardioverter-defibrillator (ICD) therapy. While the 2021 European Society of Cardiology Guidelines have discussed the advantages and considerations of adding a defibrillator in patients undergoing cardiac resynchronization therapy (CRT), the optimal selection of CRT with or without a defibrillator remains unclear, particularly in Asian populations. This is especially relevant for primary prevention using ICD, which is characterized by fewer cases of ischemic etiology compared to Western countries. Purpose This study aimed to evaluate the utility of the MADIT-ICD benefit group in Japanese CRT patients and identify key indicators for determining the necessity of CRT with or without a defibrillator. Methods We conducted a retrospective, multicenter evaluation of 505 consecutive Japanese CRT patients enrolled between 2012 and 2020. Among these patients, 76% were male, with a mean age of 65 years and a mean body mass index of 22.5 kg/m2. Ischemic etiology was present in 25% of patients, with 20% undergoing secondary prevention. The study assessed the cumulative incidences of VT/VF and non-arrhythmic mortality based on the MADIT-ICD benefit group (lowest, intermediate, and highest). Predictors for each outcome were explored, and the MADIT-ICD benefit group was validated in the Japanese cohort. Results Of the 400 included patients, 60 (15%) were categorized into the lowest MADIT-ICD benefit group, 279 (70%) into the intermediate group, and 61 (15%) into the highest group. Over a median follow-up period of 34 months, VT/VF occurred in 4 (13%), 68 (24%), and 14 (23%) patients in the lowest, intermediate, and highest benefit groups, respectively (Gray’s test, P = 0.027, Figure 1A). Non-arrhythmic death occurred in 15 (25%), 91 (33%), and 9 (15%) patients in the lowest, intermediate, and highest benefit groups, respectively (Log-rank test, P = 0.025, Figure 1B). Multivariable analysis identified MADIT-ICD VT/VF score (hazard ratio [HR] 1.23; 95% confidence interval [CI] 1.12-1.35; P < 0.001) and left bundle branch block (LBBB) (HR 0.48; 95% CI 0.27-0.86; P = 0.014) as significant predictors for VT/VF, while MADIT-ICD non-arrhythmic mortality score (HR 1.16; 95% CI 1.07-1.27; P < 0.001), serum creatinine (Cr) (HR 1.28; 95% CI 1.13-1.45; P < 0.001), and mineral corticoid receptor antagonist (MRA) use (HR 1.84; 95% CI 1.21-2.79; P = 0.004) were significant predictors for non-arrhythmic death (Table 2). Conclusion The MADIT-ICD benefit group, in conjunction with left bundle branch block and renal function, may serve as valuable predictors for determining the necessity of cardioverter-defibrillator therapy in Japanese CRT patients.Table 1 and Figure 1

All-cause mortality and incidence of appropriate therapy from a primary preventive implantable cardioverter defibrillator in patients with non-ischemic dilated cardiomyopathy

Abstract Background The DANISH study published in 2016 indicated limited benefit of primary prevention implantable cardioverter-defibrillator (ICD) in patients with non-ischemic dilated cardiomyopathy (niDCM). We aimed to investigate the long-term outcome and incidence of ICD therapy in patients with niDCM implanted on primary prevention indication during 2014-2022. Methods A total of 116 patients with niDCM were prospectively included for primary prevention ICD implantation between 2014 and 2022 in the multicenter IMPROVE study (clinical trials NCT02286908). All patients were examined with electrocardiogram, echocardiography and blood sampling at inclusion. The primary outcome was all-cause mortality, and the secondary outcome was appropriate ICD therapy. Outcomes were compared in patients included from 2014 to end of 2016 (DCM2014-16, n=49) and from 2017-2022 (DCM2017-22, n=67). Results At inclusion, patients in DCM2017-22 were younger (54 years [interquartile range (IQR) 44-68] vs. 64 years [IQR 55-70], p=0.001), had higher left ventricular ejection fraction (LVEF) (33% [IQR 25-38] vs. 24% [IQR 21-31], p<0.001) and less frequently received cardiac-resynchronization therapy defibrillator (6% vs. 29%, p=0.001) compared to DCM2014-16. Over a median 4.4-year follow-up, the all-cause mortality was 14%, of which 10% occurred in the DCM2017-22 patients (2.6 events/100 person-years), and 18% in the DCM2014-16 patients (4.0 events/100 person-years), p=0.38. There was no difference in appropriate ICD therapy between the two groups (p=0.90). Conclusion Patients receiving primary prevention ICD for niDCM after publication of the DANISH study were younger with higher LVEF, indicating a change in clinical practice after the publication. Despite this, there was no significant reduction in all-cause mortality or difference in appropriate ICD therapies. Unchanged mortality and event-rates may indicate the correct identification of high-risk patients.

Predictive value of a positive pocket swab for the occurrence of device infection in implantable cardioverter defibrillator patients undergoing generator replacement or lead revision

Abstract Introduction Bacterial colonization of generator pockets in implantable cardioverter defibrillator (ICD) patients plays a key role in the development of device infection after revision surgery. Pocket swabs taken at revision may be useful for predicting device infection, but their prognostic value is not precisely known. Aim of the study was to evaluate the predictive value of positive pocket swabs for cardiac device infection in ICD patients undergoing revision surgery. Methods A total of 646 consecutive ICD patients from a prospective single-centre ICD-registry who underwent elective device replacement, system upgrade or lead revision between 2014 and 6/2023 were analyzed. Independent predictors for device infection were evaluated by a Cox regression analysis adjusting for age, gender, EF, insulin dependent diabetes, anticoagulation, multiple leads, revision surgery and the PADIT score. Results Positive pocket swabs were obtained in 12% of patients. The baseline characteristics of ICD patients with positive versus negative pocket swabs were similar (Table 1). With an average follow-up of 3 years, the infection rate in patients with positive pocket swabs was around 5 times higher than in patients with negative swabs (19% versus 4%, p < 0.001). In a Cox regression analysis, a positive pocket swab was the strongest independent predictor for device infection during follow-up (hazard ratio 4.26, 95% confidence interval 2.15 – 8.45, Table 2). Conclusion A positive swab from ICD-pockets in patients undergoing generator replacement or lead revision is an independent predictor of device infection during follow-up. These results support the routine collection of pocket swabs from patients undergoing revision surgery.Table 1Table 2

Remote monitoring of cardiac implantable electronic devices using smart device interface versus radiofrequency-based interface: a systematic review

Abstract Background Guidelines recommended remote monitoring (RM) in managing patients with Cardiac Implantable Electronic Devices (CIED). In recent years, smart device (phone or tablet) monitoring-based RM (SM-RM) was introduced. SM-RM is a specifically developed application (app) which can be downloaded from app stores using smart devices. The app uses Bluetooth low-energy to communicate automatically and securely with the patient’s CIED. The app then uses a cellular or Wi-Fi internet connection to transfer the data securely to the manufacturer’s repository. Purpose This study aims to systematically review SM-RM versus bedside monitor RM (BM-RM) using radiofrequency in terms of compliance, connectivity, and episode transmission time. Methods We conducted a systematic review, searching three international databases from inception until July 2023 for studies comparing SM-RM (intervention group) versus BM-RM (control group). Results Two propensity score-matched studies with a total of 21978 patients were retrieved (9642 patients in the SM-RM arm and 12336 patients in the BM-RM arm) (1, 2). There is significantly higher compliance among patients using SM-RM compared with patients using BM-RM in both pacemaker and defibrillator patients. There were higher enrolment rates and completed scheduled transmissions among SM-RM compared to BM-RM. Higher connectivity was also seen in patients with SM-RM, and more SM-RM patients transmitted at least once compared to BM-RM patients. Additionally, SM-RM patients had more patient-initiated transmissions compared to BM-RM patients. Younger patients (aged <75) had more patient-initiated transmissions, and a higher proportion had ≥10 such transmissions compared with older patients (aged ≥75) in both SM-RM and BM-RM groups. The episode transmission time of SM-RM patients was also shorter than that of BM-RM patients. Conclusion SM-RM is a step in the right direction, with good compliance, connectivity, and shorter episode transmission time. It allows patients to feel empowered and in control of their health. Further research on cost-effectiveness and long-term clinical outcomes can be carried out in the future.

Sex differences in shocks and device-related complications in subcutaneous implantable-cardioverter defibrillator patients

Abstract Background The use of implantable cardioverter-defibrillators (ICDs) improves the life expectancy of patients at risk of sudden cardiac death. However, ICD treatment comes with the risk of device-related complications. As the lead is the Achilles heel of the transvenous ICD (TV-ICD), the subcutaneous ICD (S-ICD) was developed to overcome the risk of lead-related complications. It is reported for TV-ICDs that women receive less appropriate therapy, but are more likely to experience ICD-related complications than men. It is unclear whether these differences also exist among S-ICD recipients. Purpose This study investigates the differences in appropriate shocks (AS) and device-related complications in men and women implanted with an S-ICD. Methods Retrospective data was collected of all patients implanted with an S-ICD between 2009 and 2022 in our tertiary center. Propensity score matching was used to create two comparable groups that differed by sex. The numbers of patients with an AS and device related-complication requiring intervention were compared between men and women. Differences between the groups were tested using a Fisher’s exact or X2-test. Results A total of 108 men and 108 women were included in this analysis. The median age was 40 years in men and 41 years in women (p=0.747), 61% had a primary prevention indication, and the median follow-up duration was 8 years. AS were seen in 15 women versus 24 men (p=0.156). There were 6 women versus 12 men with a device-related complication requiring intervention (p=0.218) (figure). The most common complication in men was infection (4/12) whereas in women erosion of the pocket occurred most frequently (2/6). Conclusions In this study, there was no significant difference in the number of patients with AS or complication between men and women with an S-ICD. However, a trend was seen towards more shocks and complications in men. The S-ICD may be a more suitable device for women, but further research with a larger sample size is needed.sex differences in S-ICD recipients

Evaluation of cardiac implantable electronic device lead parameters before and after radiotherapy.

Radiotherapy in cancer patients with a pacemaker or an implantable cardioverter defibrillator might damage the device and possibly result in malfunction of the device. We aimed to examine device malfunction and change in lead parameters in this group. The medical records of pacemaker/implantable cardioverter defibrillator patients who underwent radiotherapy at Aalborg University Hospital between July 1, 2016, and June 30, 2021, were reviewed. Treatment was planned according to risk of device malfunction, assessed using local guidelines. Bootstrap linear regression was used to identify possible differences in lead parameters depending on beam energy and anatomical location. One hundred nine patients with a pacemaker/implantable cardioverter defibrillator who received a total of 122 radiotherapy courses in the study period were identified. No device malfunctions or significant changes in lead parameters during radiotherapy were observed. Only the left ventricle lead threshold and impedance were found to be significantly different when compared by beam energy; however, these changes were relatively small and unlikely to be of clinical relevance. No device malfunction or clinically relevant changes in lead parameters were identified in this study, suggesting that radiotherapy of pacemaker/implantable cardioverter defibrillator patients can be regarded as safe when following relevant safety precautions.

Device programing and SMART pass algorithm activation in subcutaneous implantable defibrillator patients: Data from a remote monitoring database.

The programing of subcutaneous implantable cardioverter-defibrillators (S-ICD) in clinical practice has been little studied, as the activation status of the SMART Pass filter, which was implemented to reduce inappropriate shocks. We assessed device programing during follow-up and the rate of detected arrhythmias in consecutive S-ICD recipients. We analyzed data from 670 S-ICD patients followed on the remote network at 17 Italian centers for a median of 31 months (25th-75th percentile: 16-51). The enhanced SMART Pass version, introduced in October 2022, was expected to reduce the unintentional deactivation rate. At the latest remote data transmission, the median conditional zone cut-off was set to 210bpm (25th-75th percentile: 200-220), the shock zone cutoff was 250bpm (25th-75th percentile: 240-250), and the SMART Pass was enabled in 586 (87%) patients. During follow-up, 194 automatic deactivation events were reported in 118 (18%) patients. Shocks were delivered in 129 (19%) patients, and untreated arrhythmias were recorded in 136 (20%) patients. The rate of shocks was lower when SMART Pass was enabled -0.12/patient-year (95% CI: 0.10-0.14) versus 0.20 (95% CI: 0.15-0.26) (p=.002), as it was the rate of untreated arrhythmias -0.12/patient-year (95% CI: 0.11-0.14) versus 0.23 (95% CI: 0.18-0.30) (p=.001). The enhanced SMART Pass version was associated with a lower rate of deactivations -0.04/patient-year (95% CI: 0.02-0.05) versus 0.14 (95% CI: 0.12-0.16) (p<.001), and with a reduction in treated and untreated arrhythmias (Incidence rate ratios: 0.40 (95% CI: 0.28-0.53) and 0.40 (95% CI: 0.30-0.55), respectively (p<.001)). Centers tend to program devices to detect high ventricular rates for arrhythmia detection, to minimize inappropriate shock occurrences. SMART Pass activation is associated with lower rates of detected and treated arrhythmias. The enhanced SMART Pass version seems associated with a lower deactivation rate and with a further decrease in treated arrhythmias.

No beneficial use of the wearable cardioverter defibrillator among patients suffering from inherited and congenital heart disease: data from a European multicenter registry.

Data on the use of the wearable cardioverter defibrillator in patients suffering from inherited and congenital heart disease are limited. Consequently, evidence for guideline recommendations in this patient population is lacking. In total 1,675 patients were included in a multicenter registry of eight European centers. In the present cohort, we included 18 patients suffering from congenital and inherited heart disease. Nine patients (50%) were male with a mean age of 41.3 ± 16.4 years. Four patients suffered from hypertrophic cardiomyopathy (HCM), four patients suffered from non-compaction cardiomyopathy (NCCM), two patients were diagnosed with arrhythmogenic right ventricular cardiomyopathy (ARVC) and one patient suffered from muscular dystrophy of the limb-girdle type with cardiac involvement, secondary cardiomyopathy. Three patients presented with Brugada syndrome (BrS). One patient suffered from long-QT syndrome type 1 (LQTS1). Furthermore, two patients had congenital heart defects and one patient suffered from cardiac sarcoidosis (CS). There were no appropriate/inappropriate shocks with the WCD in this cohort. One patient had recurrent self-limiting sustained ventricular tachycardia during the wear time, but actively inhibited a shock and was hospitalized. The compliance rate in this cohort was 77.8% with a mean wear time of 45.3 ± 26.9 days with a mean follow-up time of 570 ± 734 days. 55.6% (10/18) of the patients received an ICD after WCD wear time. This retrospective study of patients with inherited and congenital heart disease shows that WCD use is not beneficial in the majority of patients with inherited and congenital heart disease.

Systematic review and meta-analysis comparing cardiac resynchronization therapy with versus without defibrillation in patients with non-ischemic cardiomyopathy

Abstract Background Cardiac resynchronization therapy (CRT) stands as a notable medical breakthrough for individuals with heart failure and electrical desynchrony. This intervention aims to alleviate symptoms, diminish hospitalization rates, and enhance overall survival, both in conjunction with and without implantable cardioverter-defibrillator (ICD) therapy. Despite these advancements, the role of defibrillator therapy in addition with CRT for patients with non-ischemic cardiomyopathy (NICM) remains a topic of debate. Objective To assess and compare the outcomes of individuals diagnosed with NICM who have underwent CRT with implantable cardioverter-defibrillator (CRT-D) against those who received CRT with a pacemaker only (CRT-P). Methods We conducted a systematic search of PubMed, Embase and Cochrane database during August 2023 for studies comparing CRT-P and CRT-D in patients with nonischemic cardiomyopathy. Results Thirteen studies, including two randomized clinical trials, were incorporated, with a total of 61,326 patients providing 16,446 pooled death events (9,108 in CRT-D and 7,338 in CRT-P). The meta-analysis revealed that CRT-D was associated with a significantly lower risk of all-cause mortality compared to CRT-P (pooled HR 0.74; 95% CI: 0.62-0.88; I2=84%). Subgroup analysis focusing on propensity score-matched studies yielded consistent findings (pooled HR 0.82; 95% CI: 0.77-0.87; I² = 0%, P&amp;lt;0.001). However, subgroup analysis for patients older than 75 years suggested no statistically significant difference in mortality risk within this specific age group (pooled HR 0.96; 95% CI: 0.811-1.15; I² = 39%, P&amp;lt;0.001). Regarding the secondary endpoint of cardiovascular mortality, no significant risk reduction with CRT-D was observed (pooled HR 0.70; 95% CI: 0.49-1.01; I² = 92%), albeit with high heterogeneity. Conclusion Our study suggests that the addition of defibrillator therapy significantly reduces all-cause mortality in CRT-eligible patients with NICM, although results were not observed for patients older than 75 years.All-cause MortalityPatients older 75 years old

Short- and long-term patient-reported outcomes of subcutaneous implantable cardioverter-defibrillator therapy

Abstract Background The safety and efficacy of subcutaneous implantable cardioverter-defibrillator (S-ICD) therapy are well-established. However, there is a paucity of patient-reported outcome data, despite the increasing emphasis on incorporating patients' perspectives into quality care assessments. Current guidelines also recommend evaluating psychological status and addressing distress in defibrillator patients. Purpose This study aims to assess perioperative and postoperative pain during S-ICD implantation, along with patient acceptance during follow-up. We also explore associations between these outcomes, clinical characteristics, and implantation variables. Methods A total of 149 consecutive patients (87% male, mean age 53±13 years, body mass index 27±4 Kg/m², ejection fraction 39±14%) who underwent S-ICD implantation across 11 centers were analyzed. Short-term endpoints included pain during and 6 hours after the procedure. Pain intensity was rated on a 10-point visual analogue scale. Long-term endpoint was S-ICD patient acceptance measured (on a 0-to-100 point scale) by the Florida Patients Acceptance Survey (FPAS) score and its components: Return to Function (RTF), Device-Related Distress (DRD), Positive Appraisal (PA), and Body Image Concerns (BIC). The survey was administered 12 months post-implantation. Results The S-ICD generator was positioned in an intermuscular pocket in 140 (94%) patients. Serratus anterior plane block (SAPB) was performed in 103 (69%) patients. 72 (48%) patients underwent the defibrillation testing. Implantation success was reported in all patients without operative complications. Overall, pain intensity during implantation was 2 [25th-75th percentile: 1-4], and 1 [1-2] for static pain and 2 [1-3] for dynamic pain, 6 hours post-procedure. SAPB was associated with significantly lower pain intensity during implantation (2 [1-3] vs. 4 [2-5], p&amp;lt;0.001) and non-significantly lower values of dynamic pain intensity 6 hours post-procedure (1 [1-2] versus 2 [1-3], p=0.076). The other tested variables, i.e. age, sex, body habitus, ejection fraction, omission of defibrillation testing, were not associated with different pain levels. S-ICD acceptance scores were favorable overall (total FPAS 77 [63-87], RTF 69 [56-88], DRD 25 [10-45], PA 88 [75-100], BIC 13 [0-38]). Patients who underwent SAPB exhibited better RTF (75 [56-88] versus 63 [50-69], p=0.002) and PA (88 [75-100] versus 75 [69-94], p=0.004). Conclusions S-ICD implantation resulted in minimal discomfort, especially with novel anesthetic techniques. Overall, patients reported good acceptance of the S-ICD. Improved acceptance was observed in patients who underwent SAPB, highlighting the significance of enhanced patient implantation experience for long-term outcomes.

Efficacy of a gentamycin-collagen sponge to prevent infection in implantable cardioverter defibrillator patients undergoing revision surgery - results of a monocentric ICD registry observational study

Abstract Introduction Despite the obvious benefits, the use of implantable cardioverter defibrillators (ICDs) is associated with serious complications, including infections. In particular, device replacement or revision procedures are associated with an increased risk of infection. Aim of the study was to compare the cardiac device infection rate with and without the use of the gentamycin-collagen sponge (GCS) in patients undergoing device replacement or revision procedures of implanted ICDs. Methods A total of 491 consecutive ICD patients from a prospective single-centre ICD-registry who underwent elective device replacement, system upgrade or lead revision between 2017 and 6/2023 were analyzed. From September 2020 onwards, a GCS was inserted into the device pocket (GCS group, n = 256). These patients were compared to the patients implanted/ revised between 2017 and 8/2020 (control group, n = 235). Results The baseline characteristics and the PADIT score were similar in both groups (Table 1). The GCS was well tolerated and there were no complications associated with the GCS. The mean follow-time was 15 + 10 months in the GCS group and 30 + 11 months in the control group. The Kaplan-Meier estimated infection rate after one year was 1.0% in the GCS group and 3.5% in the control group (p = 0.03, Figure 1). Time from revision to infection was 144 + 134 days in the GCS group vs. 362 + 297 days in the control group. Conclusion Adjunctive use of a GCS was associated with a lower incidence of device infections than standard-of-care infection-prevention strategies alone.

Device programming and SMART pass algorithm activation in subcutaneous implantable defibrillator patients: data from a remote monitoring database

Abstract Background In subcutaneous implantable cardioverter-defibrillator (S-ICD) recipients, a previous study demonstrated very low rates of delivered shocks and inappropriate shocks on programming a conditional zone between 200 and 250 bpm and a shock zone for arrhythmias &amp;gt;250 bpm. The extent to which this programming approach is adopted in clinical practice has been little studied, as the activation status of the SMART Pass filter, that was implemented to reduce inappropriate shocks and enhanced over time. Purpose We assessed device programming during follow-up and the rate of detected arrhythmias in a cohort of consecutive S-ICD recipients. Methods We analyzed data from 670 S-ICD patients followed on the remote network at 17 Italian centers for a median of 31 months (25th-75th percentile: 16-51). The enhanced SMART Pass version was available for all patients after October 2022. It makes the deactivation monitor less sensitive to premature ventricular contractions or other transient amplitude changes while maintaining arrhythmia sensitivity and specificity, and it was expected to reduce unintentional deactivation rate. Results At the last remote data transmission, the median programmed conditional zone cut-off was set to 210 bpm (25th-75th percentile: 200-220), the shock zone cut-off was 250 bpm (25th-75th percentile: 240-250), and the SMART Pass was enabled in 586 (87%) patients. During follow-up, 194 automatic deactivation events (0.10/patient-year) were reported in 118 (18%) patients. The SMART Pass-disabled time was 13% of the total observation period. Shocks were delivered in 129 (19%) patients (rate: 0.13/patient-year), and untreated arrhythmias were recorded in 136 (20%) patients (rate: 0.14/patient-year). The rate of shocks was lower when SMART Pass was enabled – 0.12/patient-year (95% CI: 0.10-0.14) versus 0.20 (95%CI: 0.15-0.26) (p=0.002), as it was the rate of untreated arrhythmias – 0.12/patient-year (95% CI: 0.11-0.14) versus 0.23 (95%CI: 0.18-0.30) (p=0.001). The enhanced SMART Pass version was associated with a lower rate of deactivations – 0.04/patient-year (95%CI: 0.02-0.05) versus 0.14 (95% CI: 0.12-0.16) (p&amp;lt;0.001), and with a reduction in treated and untreated arrhythmias (Incidence rate ratios: 0.40 (95%CI: 0.28-0.53) and 0.40 (95%CI: 0.30-0.55), respectively (p&amp;lt;0.001)). Conclusions In current clinical practice, S-ICD implantation centers often program high cut-off rates for arrhythmia detection. Most patients have SMART Pass consistently enabled during follow-up. This is associated with significantly lower rates of detected and treated arrhythmias. The enhanced SMART Pass version seems associated with lower deactivation rate, and with further decrease in treated and untreated detected arrhythmias.

Remote monitoring of cardiac implantable electronic devices using smart device interface versus radiofrequency‐based interface: A systematic review

AbstractBackgroundGuidelines recommended remote monitoring (RM) in managing patients with Cardiac Implantable Electronic Devices. In recent years, smart device (phone or tablet) monitoring‐based RM (SM‐RM) was introduced. This study aims to systematically review SM‐RM versus bedside monitor RM (BM‐RM) using radiofrequency in terms of compliance, connectivity, and episode transmission time.MethodsWe conducted a systematic review, searching three international databases from inception until July 2023 for studies comparing SM‐RM (intervention group) versus BM‐RM (control group).ResultsTwo matched studies (21 978 patients) were retrieved (SM‐RM arm: 9642 patients, BM‐RM arm: 12 336 patients). There is significantly higher compliance among SM‐RM patients compared with BM‐RM patients in both pacemaker and defibrillator patients. Manyam et al. found that more SM‐RM patients than BM‐RM patients transmitted at least once (98.1% vs. 94.3%, p &lt; .001), and Tarakji et al. showed that SM‐RM patients have higher success rates of scheduled transmissions than traditional BM‐RM methods (SM‐RM: 94.6%, pacemaker manual: 56.3%, pacemaker wireless: 77.0%, defibrillator wireless: 87.1%). There were higher enrolment rates, completed scheduled and patient‐initiated transmissions, shorter episode transmission time, and higher connectivity among SM‐RM patients compared to BM‐RM patients. Younger patients (aged &lt;75) had more patient‐initiated transmissions, and a higher proportion had ≥10 transmissions compared with older patients (aged ≥75) in both SM‐RM and BM‐RM groups.ConclusionSM‐RM is a step in the right direction, with good compliance, connectivity, and shorter episode transmission time, empowering patients to be in control of their health. Further research on cost‐effectiveness and long‐term clinical outcomes can be carried out.

Association between defibrillation-to-adrenaline interval and short-term outcomes in patients with out-of-hospital cardiac arrest and an initial shockable rhythm

AimThe optimal timing of adrenaline administration after defibrillation in patients with out-of-hospital cardiac arrest (OHCA) and an initial shockable rhythm is unknown. We investigated the association between the defibrillation-to-adrenaline interval and clinical outcomes. MethodsBetween 2011 and 2020, we enrolled 1,259,960 patients with OHCA into a nationwide prospective population-based registry in Japan. After applying exclusion criteria, 20,905 patients with an initial shockable rhythm documented at emergency medical services (EMS) arrival who received adrenaline after defibrillation were eligible for this study. Multivariable logistic regression analysis was used to predict favourable short-term outcomes: prehospital return of spontaneous circulation (ROSC), 30-day survival, or a favourable neurological outcome (Cerebral Performance Category 1 or 2) at 30 days. Patients were categorised into 2-minute defibrillation-to-adrenaline intervals up to 18 min, or more than 18 min. ResultsAt 30 days, 1,618 patients (8%) had a favourable neurological outcome. The defibrillation-to-adrenaline interval in these patients was significantly shorter than in patients with an unfavourable neurological outcome [8 (5–12) vs 11 (7–16) minutes; P < 0.001]. The proportion of patients with prehospital ROSC, 30-day survival, or a favourable neurological outcome at 30 days decreased as the defibrillation-to-adrenaline interval increased (P < 0.001 for trend). Multivariable analysis revealed that a defibrillation-to-adrenaline interval of > 6 min was an independent predictor of worse prehospital ROSC, 30-day survival, or neurological outcome at 30 days when compared with an interval of 4–6 min. ConclusionA longer defibrillation-to-adrenaline interval was significantly associated with worse short-term outcomes in patients with OHCA and an initial shockable rhythm.

Comparison of infection and complication rates associated with transvenous vs. subcutaneous defibrillators in patients with stage 4 chronic kidney disease: a multicenter long-term retrospective follow-up.

Patients with progressive chronic kidney disease (CKD) are at higher risk of infections and complications from cardiac implantable electronic devices (CIED). In patients with a primary or secondary prophylactic indication, implantable cardiac defibrillators (ICD) can prevent sudden cardiac deaths (SCD). We retrospectively compared transvenous-ICD (TV-ICD) and intermuscularly implanted subcutaneous-ICD (S-ICD) associated infections and complication rates together with hospitalizations in recipients with stage 4 kidney disease. We retrospectively analyzed 70 patients from six German centers with stage 4 CKD who received either a prophylactic TV-ICD with a single right ventricular lead, 49 patients, or a S-ICD, 21 patients. Follow-Ups (FU) were performed bi-annually. The TV-ICD patients were significantly older. This group had more patients with a history of atrial arrhythmias and more were prescribed anti-arrhythmic medication compared with the S-ICD group. There were no significant differences for other baseline characteristics. The median and interquartile range of FU durations were 55.2 (57.6-69.3) months. During FU, patients with a TV-ICD system experienced significantly more device associated infections (n = 8, 16.3% vs. n = 0; p < 0.05), device-associated complications (n = 13, 26.5% vs. n = 1, 4.8%; p < 0.05) and device associated hospitalizations (n = 10, 20.4% vs. n = 1, 4.8%; p < 0.05). In this long-term FU of patients with stage 4 CKD and an indication for a prophylactic ICD, the S-ICD was associated with significantly fewer device associated infections, complications and hospitalizations compared with TV-ICDs.

Cardiac implantable electronic devices and bloodstream infections: management and outcomes.

Bloodstream infection (BSI) of any cause may lead to device infection in cardiac implantable electronic device (CIED) patients. Aiming for a better understanding of the diagnostic approach, treatment, and outcome, patients with an implantable cardioverter defibrillator (ICD) and cardiac resynchronization therapy and defibrillator (CRT-D) hospitalized with BSI were investigated. This is a single-centre, retrospective, cohort analysis including consecutive ICD/CRT-D patients implanted between 2012 and 2021. These patients were screened against a list of all hospitalized patients having positive blood cultures consistent with diagnosed infection in any department of a local public hospital. The total cohort consisted of 515 patients. Over a median follow-up of 59 months (interquartile range 31-87 months), there were 47 BSI episodes in 36 patients. The majority of patients with BSI (92%) was admitted to non-cardiology units, and in 25 episodes (53%), no cardiac imaging was performed. Nearly all patients (85%) were treated with short-term antibiotics, whereas chronic antibiotic suppression therapy (n = 4) and system extraction (n = 3) were less frequent. Patients with BSI had a nearly seven-fold higher rate (hazard ratio 6.7, 95% confidence interval 3.9-11.2; P < .001) of all-cause mortality. Diagnostic workup of defibrillator patients with BSI admitted to a non-cardiology unit is often insufficient to characterize lead-related endocarditis. The high mortality rate in these patients with BSI may relate to underdiagnosis and consequently late/absence of system removal. Efforts to increase an interdisciplinary approach and greater use of cardiac imaging are necessary for timely diagnosis and adequate treatment.

Hospital Variation in Epinephrine Administration Before Defibrillation for Cardiac Arrest Due to Shockable Rhythm.

Contrary to advanced cardiac life support guidelines that recommend immediate defibrillation for shockable in-hospital cardiac arrest (IHCA), epinephrine administration before first defibrillation is common and associated with lower survival at a "patient-level." Whether this practice varies across hospitals and its association with "hospital-level" IHCA survival remains unknown. The purpose of this study was to determine hospital variation in rates of epinephrine administration before defibrillation for shockable IHCA and its association with IHCA survival. Observational cohort study. Five hundred thirteen hospitals participating in the Get With The Guidelines Resuscitation Registry. A total of 37,668 adult patients with IHCA due to an initial shockable rhythm from 2000 to 2019. Epinephrine before first defibrillation. Using multivariable hierarchical regression, we examined hospital variation in epinephrine administration before first defibrillation and its association with hospital-level rates of risk-adjusted survival. The median hospital rate of epinephrine administration before defibrillation was 18.8%, with large variation across sites (range, 0-68.8%; median odds ratio: 1.54; 95% CI, 1.47-1.61). Major teaching status and annual IHCA volume were associated with hospital rate of epinephrine administration before defibrillation. Compared with hospitals with the lowest rate of epinephrine administration before defibrillation (Q1), there was a stepwise decline in risk-adjusted survival at hospitals with higher rates of epinephrine administration before defibrillation (Q1: 44.3%, Q2: 43.4%; Q3: 41.9%; Q4: 40.3%; p for trend < 0.001). Administration of epinephrine before defibrillation in shockable IHCA is common and varies markedly across U.S. hospitals. Hospital rates of epinephrine administration before defibrillation were associated with a significant stepwise decrease in hospital rates of risk-adjusted survival. Efforts to prioritize immediate defibrillation for patients with shockable IHCA and avoid early epinephrine administration are urgently needed.

The effect of virtual interactive nurse-led support group intervention on fatigue, shock anxiety, and acceptance of implantable cardioverter defibrillator patients: a randomized trial

BackgroundImplantable cardioverter defibrillators (ICD), as a gold and standard treatment for fatal cardiac arrhythmia, may lead to some physical and psychological problems for the patients. Therefore, performing some interventions to reduce or eliminate these issues is crucial. This study aimed to determine the effect of virtual interactive nurse-led support group intervention on fatigue, shock anxiety, and acceptance of ICD patients.MethodsThis is a clinical trial study on 72 patients with ICD. They were randomly allocated to the intervention (n = 36) and control (n = 36) groups. A virtual interactive nurse-led support group intervention through WhasApp was performed for one month. Multidimensional fatigue inventory, Florida Shock Anxiety Scale, and Florida Patient Acceptance Scale were used. Data were analyzed to perform the analysis of data through SPSS, using independent and paired-t test, Mann-Whitney U test, Wilcoxon test, and ANCOVA.ResultsBefore the intervention, no significant difference was observed between the two groups with regard to fatigue, shock anxiety, and ICD acceptance. However, after the intervention, a significant difference was found between the two groups with regard to fatigue, shock anxiety, and ICD acceptance (P < 0.05).ConclusionThis study showed that virtual interactive nurse-led support group intervention reduced fatigue and shock anxiety and improved the ICD acceptance.Practice implicationsThis flexible, accessible, and interactive nurse-led support group intervention is suggested to be used for ICD patients.Trial registrationThis trial was registered and approved by Iranian Registry of Clinical Trials (Trial Id: 60,738, date: (24/02/2022). (https://www.irct.ir/trial/60738).

The Effect of Education, Telephone Monitoring on Self-Efficacy and Shock Anxiety of Implantable Cardioverter Defibrillator Patients

Objective: Implantable cardioverter defibrillators (ICDs), which are used in the treatment of fatal ventricular arrhythmias, have many life-saving benefits. On the other hand, it has negative effects in terms of physical, social and psychological aspects by commonly causing anxiety and depression. The aim of this study is to examine the effects of education and telephone monitoring on self-efficacy and shock anxiety in patients with implantable cardioverter defibrillator implantation.&#x0D; Methods: 65 patients hospitalized for ICD insertion were randomly divided into intervention (n=33) and control (n=32) groups. The intervention group was given a training booklet prepared by one-on-one training about ICD. Telephone monitoring was performed once every two weeks for three months and then once a month. No intervention was applied to the control group. Self-Efficacy and Outcome Expectation Scales, Florida Shock Anxiety Scale were applied in the third and sixth months after ICD implantation in both groups.&#x0D; Results: The self-efficacy scores at the sixth month were higher in the intervention group than in the control group (p=.03). There was no difference between the shock anxiety scores at 3 months (p=.58) and 6 months (p=.64) between the groups. Shock anxiety mean scores of both groups in the 6th month are lower than the mean scores in the 3rd month (p