Implantable Cardioverter-defibrillator For Secondary Prevention Research Articles

Clinical profile and outcomes of young patients treated with implantable cardioverter defibrillators at a South African tertiary hospital: a review of two decades of implantable cardioverter defibrillator implantation and follow up.

In young patients without atherosclerotic coronary artery disease, the aetiology of sudden cardiac death (SCD) has been described in Europe and North America. However, there are important regional variations and there are limited data on the aetiology and outcome of SCD in South Africa. The objective of this study was to determine the profile and outcomes of young patients treated with implantable cardioverter defibrillators (ICDs) at a South African tertiary hospital. This study was designed as a retrospective review of patients aged 35 years or younger implanted with ICDs at Groote Schuur Hospital. During the study period, 38 patients younger than 35 years were implanted with ICDs. The mean (standard deviation) age at ICD implantation was 25.1 (7.6) years and 63.2% were male. A secondary-prevention ICD was implanted in 57.9% of the patient population, and primary prevention in the remaining 42.1%. Patients with secondary-prevention ICDs presented with ventricular tachycardia (59.1%), ventricular fibrillation (31.8%) and receipt of cardiopulmonary resuscitation but no recorded electrocardiograms (9.1%). Arrhythmogenic right ventricular cardiomyopathy (ARVC) was the leading cause of SCD in the secondary-prevention patient population (36.4%). Idiopathic dilated cardiomyopathy accounted for 50% of the primary-prevention patient population. After a median (interquartile range) follow up 32 (14-90) months, 7.9% died and 5.2% received a heart transplant; 42.1% of the study population received appropriate ICD shock therapies and 18.4% received inappropriate shock therapies. In this single-centre study from South Africa, ARVC and repaired congenital heart disease were the leading causes of SCD in patients younger than 35 years treated with secondary-prevention ICDs. Primary-prevention ICDs were frequently implanted for idiopathic dilated cardiomyopathy.

Effectiveness of the risk stratification proposed by the 2022 European Heart Rhythm Association Expert Consensus statement on arrhythmic mitral valve prolapse

Recently, an expert consensus statement proposed indications where implantation of a primary prevention implantable cardioverter-defibrillator (ICD) may be reasonable in patients with mitral valve prolapse (MVP). The objective was to evaluate the proposed risk stratification by the expert consensus statement. Consecutive patients with MVP without alternative arrhythmic substrates with cardiac magnetic resonance imaging (CMR) were included in a single-center retrospective registry. Arrhythmic MVP (AMVP) was defined as a total premature ventricular complex burden ≥5%, non-sustained ventricular tachycardia (VT), VT, or ventricular fibrillation. The end point was a composite of SCD, VT, inducible VT, and appropriate ICD shocks. In total, 169 patients (52.1% male, median age 51.4 years) were included and 99 (58.6%) were classified as AMVP. Multivariate logistic regression identified the presence of late gadolinium enhancement (OR 2.82, 95%CI 1.45-5.50) and mitral annular disjunction (OR 1.98, 95%CI 1.02-3.86) as only predictors of AMVP. According to the EHRA risk stratification, 5 patients with AMVP (5.1%) had a secondary prevention ICD indication, while in 69 patients (69.7%) the implantation of an ICD may be reasonable. During a median follow-up of 8.0 years (IQR 5.0-15.6), the incidence rate for the composite arrhythmic end point was 0.3%/year (95%CI 0.1-0.8). More than half of MVP patients referred for CMR met the AMVP diagnostic criteria. Despite low long-term event rates, in 70% of patients with AMVP the implantation of an ICD may be reasonable. Risk stratification of SCD in MVP remains an important knowledge gap and requires urgent investigation.

Appropriate Implantable Cardioverter-Defibrillator Therapy in Patients with Ventricular Arrhythmia of Unclear Cause in Secondary Prevention of Sudden Cardiac Death.

In this study, we sought to investigate the occurrence of appropriate implantable cardioverter-defibrillator (ICD) therapies and inappropriate shocks in secondary prevention ICD recipients with ventricular arrhythmia of unclear cause and ventricular arrhythmia in the context of underlying heart disease. In this retrospective study, consecutive patients with an ICD implanted for secondary prevention in the University Medical Center Groningen (UMCG), the Netherlands between 1 January 2012 and 31 December 2018 were included. Patients were classified as having ventricular arrhythmia of unclear cause if no clear cause was found which could explain the index ventricular arrhythmia. The primary outcome was appropriate ICD therapy. The study population consisted of 257 patients. In 220 patients, an underlying heart disease could be identified as the cause of ventricular arrhythmia, while 37 patients had an unclear cause of ventricular arrhythmia. The median age was 64 years (interquartile range (IQR) 53-72 years). Forty-five (18%) patients were women. During a median duration of follow-up of 6.2 years (IQR 4.8-7.8 years), appropriate ICD therapy occurred in 95 (37%) patients. This number was 90 (41%) in the group with a clear etiology and 5 (14%) in the group with an unclear etiology. In multivariable analysis, index ventricular arrhythmia of unclear cause was associated with fewer appropriate ICD therapies (HR 0.37 [95% CI 0.14-0.99]; p = 0.048), as well as an increased risk of inappropriate ICD shocks (HR 3.71 [95% CI 1.17-11.80]; p = 0.026). Index ventricular arrhythmia of unclear cause was significantly associated with fewer appropriate ICD therapies.

Long-term Clinical Outcomes of Implantable Cardioverter Defibrillator Recipients in New Zealand

The long-term clinical outcomes of implantable cardioverter defibrillator (ICD) recipients across New Zealand are unknown. This study provides a detailed analysis of long-term clinical outcomes of ICD recipients in New Zealand over the past decade. All patients with an ICD implant between 2010 and 2019 were identified using the National Minimum Dataset, which collects all public hospital admissions in New Zealand using International Statistical Classification of Diseases and Related Health Problems, Tenth Revision, Australian Modification (ICD10-AM) procedure coding. There were 4,261 patients with a mean follow-up of 4.85±2.76 years. There were 1,739 (40.8%) primary prevention and 2,522 (59.2%) secondary prevention ICD recipients. The median age was 62 years and 78.9% were male. There was no significant difference in all-cause mortality between primary prevention or secondary prevention ICD recipients (21.7% vs 21.9%, p=0.99). In the primary prevention ICD group, heart failure (HF) hospitalisation more frequently occurred (32.7% vs 26.1%, p<0.001) but hospitalisations with ventricular arrhythmia (VA) were less common (16.7% vs 27.1%, p<0.001). Compared with ICD recipients with non-ischaemic aetiology for HF, those with ischaemic HF had higher all-cause mortality (30.0% vs 16.1%, p<0.001), HF hospitalisation (38.0% vs 22.4%, p<0.001), and hospitalisation with VA (27.9% vs 19.4%, p<0.001). In New Zealand ICD recipients, there was no difference in all-cause mortality between primary prevention and secondary prevention ICD implants. However, ICD recipients with ischaemic aetiology for HF had significantly higher all-cause mortality, HF hospitalisation, and hospitalisation with VA.

Ventricular tachycardia as presenting arrhythmia as a determinant of appropriate implantable cardioverter-defibrillator therapy in secondary prevention

Abstract Funding Acknowledgements Type of funding sources: None. Background Sudden cardiac death (SCD) is a leading cause of death. The implantable cardioverter-defibrillator (ICD) is an established therapy to prevent SCD in patients with prior ventricular tachycardia (VT) or ventricular fibrillation (VF). Determination of patient characteristics related to ICD therapies may provide targets for more intensive monitoring or management of ventricular arrhythmias. Therefore, we aimed to find determinants of appropriate ICD therapy. Methods In this retrospective, single-centre study, 223 consecutive secondary prevention ICD recipients were included. Data was obtained on medical history, laboratory measurements, electrocardiography and echocardiography. The primary outcome was appropriate ICD therapy, which included shock and antitachycardia pacing (ATP) given for VF or VT. Backward stepwise Cox regression analysis was performed to find determinants of appropriate therapy. Results The median age of the study population was 65.3 years (interquartile range (IQR) 55.4 – 72.0 years). 188 (84.3%) patients were male. 153 (68.6%) patients had ischemic heart disease. During a median follow-up duration of 6.00 years (interquartile range (IQR) 4.85 – 7.70 years), appropriate ICD therapy occurred in 89 (39.9%) patients, appropriate ICD shock in 65 (29.1%) patients, death in 55 (24.7%), inappropriate shock in 11 (4.9%) and device-related complications in 18 (8.1%). VT as index arrhythmia, QRS fragmentation and diminished right ventricular function were determinants of appropriate device therapy. Interestingly, whereas the majority of patients (141 (63.2%)) had an ICD implanted for initial presentation with VF, the first occurrence of appropriate therapy during follow-up was for monomorphic VT in the majority of patients (84 (94.4%)). Conclusion In patients with a secondary prevention ICD indication, VT as presenting arrhythmia is a determinant of appropriate ICD therapy during follow-up. Most ICD therapies during follow-up were applied for monomorphic VT.

Highlights From the Circulation Family of Journals.

Highlights From the Circulation Family of Journals.

Machine Learning-Based Phenomapping in Patients with Heart Failure and Secondary Prevention Implantable Cardioverter-Defibrillator Implantation: A Proof-of-Concept Study.

Previous studies have failed to implement risk stratification in patients with heart failure (HF) who are eligible for secondary implantable cardioverter-defibrillator (ICD) implantation. We aimed to evaluate whether machine learning-based phenomapping using routinely available clinical data can identify subgroups that differ in characteristics and prognoses. A total of 389 patients with chronic HF implanted with an ICD were included, and forty-four baseline variables were collected. Phenomapping was performed using hierarchical k-means clustering based on factor analysis of mixed data (FAMD). The utility of phenomapping was validated by comparing the baseline features and outcomes of the first appropriate shock and all-cause death among the phenogroups. During a median follow-up of 2.7 years for device interrogation and 5.1 years for survival status, 142 (36.5%) first appropriate shocks and 113 (29.0%) all-cause deaths occurred. The first 12 principal components extracted using the FAMD, explaining 60.5% of the total variability, were left for phenomapping. Three mutually exclusive phenogroups were identified. Phenogroup 1 comprised the oldest patients with ischemic cardiomyopathy; had the highest proportion of diabetes mellitus, hypertension, and hyperlipidemia; and had the most favorable cardiac structure and function among the phenogroups. Phenogroup 2 included the youngest patients, mostly those with non-ischemic cardiomyopathy, who had intermediate heart dimensions and function, and the fewest comorbidities. Phenogroup 3 had the worst HF progression. Kaplan-Meier curves revealed significant differences in the first appropriate shock (p = 0.002) and all-cause death (p 0.001) across the phenogroups. After adjusting for medications in Cox regression, phenogroups 2 and 3 displayed a graded increase in appropriate shock risk (hazard ratio [HR] 1.54, 95% confidence interval [CI] 1.03-2.28, p = 0.033; HR 2.21, 95% CI 1.42-3.43, p 0.001, respectively; p for trend 0.001) compared to phenogroup 1. Regarding mortality risk, phenogroup 3 was associated with an increased risk (HR 2.25, 95% CI 1.45-3.49, p 0.001). In contrast, phenogroup 2 had a risk (p = 0.124) comparable with phenogroup 1. Machine-learning-based phenomapping can identify distinct phenotype subgroups in patients with clinically heterogeneous HF with secondary prophylactic ICD therapy. This novel strategy may aid personalized medicine for these patients.

Inter-American Society of Cardiology (CIFACAH-ELECTROSIAC) and Latin-American Heart Rhythm Society (LAHRS): multidisciplinary review on the appropriate use of implantable cardiodefibrillator in heart failure with reduced ejection fraction

BackgroundOur main objective was to present a multidisciplinary review on the epidemiology of sudden cardiac death (SCD) and the tools that could be used to identify malignant ventricular arrhythmias (VAs) and to perform risk stratification. In addition, indications and contraindications for the use of implantable cardioverter defibrillator (ICD) in general and in special populations including the elderly and patients with chronic kidney disease (CKD) are also given.MethodsAn expert group from the Inter American Society of Cardiology (IASC), through their HF Council (CIFACAH) and Electrocardiology Council (ElectroSIAC), together with the Latin American Heart Rhythm Society (LAHRS), reviewed and discussed the literature regarding the appropriate use of an ICD in people with heart failure (HF) with reduced ejection fraction (HFpEF). Indications and contraindications for the use of ICD are presented in this multidisciplinary review.ResultsNumerous clinical studies have demonstrated the usefulness of ICD in both primary and secondary prevention of SCD in HFpEF. There are currently precise indications and contraindications for the use of these devices.ConclusionsIn some Latin American countries, a low rate of implantation is correlated with low incomes, but this is not the case for all Latin America. Determinants of the low rates of ICD implantation in many Latin American countries are still a matter of research. VA remains one of the most common causes of cardiovascular death associated with HFrEF and different tools are available for stratifying the risk of SCD in this population.

Outcome of patients with idiopathic ventricular fibrillation and correlation with ECG markers of early repolarization

BackgroundEarly repolarization pattern (ERP) has been associated with idiopathic ventricular fibrillation (IVF) and with cardiovascular mortality in the general population. As there is limited data about long- term outcome of IVF, the aim of our study was to observe ventricular arrhythmia (VA) recurrences in these patients and to identify a possible correlation of VA with ECG markers of early repolarization.Methods and resultsWe investigated 56 consecutive IVF patients who received an implantable cardioverter-defibrillator for secondary prevention. ERP was defined as a J-point elevation ≥ 0.1 mV in two or more contiguous inferior or lateral leads. Markers of early repolarization were present in 32.1% of cases with a preponderance of QRS slurring (77.8%). During a mean follow-up of 41.2 months, 11 patients (19.6%) received in total 18 adequate ICD-therapies. VF was most the common cause for ICDtherapy (61.1%) but monomorphic VT also occurred in four patients. Presence of ERP was associated with a significant trend towards arrhythmia recurrences. 38.9% patients with ERP received appropriate ICD-therapies whereas only 10.5% of patients without ERP had arrhythmia recurrence (p = 0.05). Inappropriate ICD-therapies occurred in seven patients (12.5%) with a non-significant trend towards a higher incidence in patients with a transvenous ICD (p = 0.15).ConclusionA significant correlation between ERP and VA recurrences in patients with IVF could be observed. Though monomorphic VA also play a role in the studied IVF-population, our data support the use of the S-ICD in this collective.Graphical abstract

Recurrent Out-of-Hospital Sudden Cardiac Arrest: Prevalence and Clinical Factors.

Despite improvements in management following survival from sudden cardiac arrest (SCA) and wide availability of implantable cardioverter defibrillators for secondary prevention, a subgroup of individuals will suffer multiple distinct episodes of SCA. The objective of this study was to characterize and evaluate the burden of recurrent out-of-hospital SCA among survivors of SCA in a single large US community. SCA cases were prospectively ascertained in the Oregon Sudden Unexpected Death Study. Individuals that experienced recurrent SCA were identified both prospectively and retrospectively. We ascertained 6649 individuals with SCA (2002-2020) and 924 (14%) survived to hospital discharge. Of these, 88 survivors (10%) experienced recurrent SCA. Of the nonsurvivors (n=5725), 35 had suffered a recurrent SCA. Of the total 123 SCA cases with recurrent SCA, >60% occurred at least 1 year after the initial SCA (median 23 months, range: 6 days to 31 years). SCA occurred despite a secondary prevention implantable cardioverter defibrillator in 22% (n=26). Prevalence of coronary disease (36% versus 25%), hypertension (69% versus 43%), diabetes (44% versus 21%), and chronic kidney disease (35% versus 14%) was significantly higher in recurrent SCA versus single SCA survivors (n=80, P=0.01). Among individuals with no secondary prevention implantable cardioverter defibrillators before recurrent SCA, the majority had apparently reversible etiologies identified at initial SCA, with one-quarter undergoing coronary revascularization and over half diagnosed with noncoronary cardiac etiologies. At least 10% of SCA survivors had recurrent SCA, and a large subgroup suffered their repeat SCA despite treatment for an apparently reversible etiology. A renewed focus on careful assessment of cardiac substrate as well as management of coronary disease, hypertension, diabetes, and chronic kidney disease in SCA survivors could reduce recurrent SCA.

Abstract 9472: Effects of Social Determinants of Health on ICD Shocks, Hospitalizations, &amp; Mortality in the First Year After an ICD

Introduction: Disparities in the receipt of an implantable cardioverter defibrillator (ICD) have been reported. African Americans (AA), women, and those with lower SES are less likely to receive an ICD and more likely to report poor outcomes after ICD implant. The purpose of this study was to determine if social determinants of health (SDOH) were associated with the number of ICD shocks experienced, all cause hospitalization, or mortality in the first year following receipt of an initial ICD. Hypothesis: SDOH (age, race, biological sex, annual income, employment, education, rural vs urban locale) are related to total ICD shocks, all cause hospitalization, and mortality in the first year after an initial ICD. Methods: 301 patients who received an initial ICD (58% primary prevention, 42% secondary prevention) were followed for 1 year. Patients were 64 ± 2 years old, 91% Caucasian, 4% AA, 2% Am Indian (AI), 2% Latinx, 74% male, 87% urban , 65% retired-disabled, 45% household income &lt; $50K, and 48% high school education or less. ICD shocks, hospitalizations, &amp; deaths were verified using the EMR. Descriptive statistics, correlations, and multivariate logistic regression were used to examine for SHOD related disparities in health outcomes over 1 year. Results: There were no significant associations between SDOH and ICD shocks, all cause hospitalization, or mortality over 1 year. ICD shocks : 34 patients (11.3%) had at least 1 ICD shock over 12-months of follow-up. The number of ICD shocks was higher for those who engaged in hazardous drinking (25%: 5% women, 20% men, p=0.03), and those who received an ICD for secondary prevention (primary 8.4%, secondary 15.4% (p=0.04) at baseline.. Hospitalization : 95 patients (31.6%) were hospitalized over the 12 months of follow-up. Mortality : 9 (3%) deaths (67% cardiac related) were recorded over the 12 months, with no associations found between SDOH and mortality. Conclusions: SDOH were not associated with the incidence of ICD shocks, all-cause hospitalization, or mortality in the first year after receipt of an initial ICD. SDOH influences on access to receipt of an initial ICD may have contributed to the observed outcomes post-ICD.

Abstract 9972: Sex-Related Differences and the Influence of Pregnancy on Cardiac Outcomes in Adults With a Systemic Right Ventricle and Biventricular Physiology

Introduction: Transposition of the great arteries (TGA) with a systemic right ventricle (sRV) and biventricular physiology is associated with increased morbidity and mortality. There is a paucity of data regarding sex-related differences in outcomes in the context of a sRV. Moreover, pregnancy has been associated with deterioration of sRV function in short-term post-partum follow-up, but the long-term impact remains largely unknown. Methods and Results: A retrospective cohort study was conducted on 214 adults, age 44.7±12.3 years, with a sRV and biventricular physiology followed for a median of 13 years at an adult congenital heart disease center. No sex-related difference was identified in the prevalence of atrial or ventricular arrhythmias, permanent pacemaker implantation, hospitalization for heart failure, systemic atrio-ventricular valve intervention, heart transplant, or cardiac death. Among the 82 (38.3%) women, age 44.0±12.5 years, 43 (52.4%) had at least one full-term pregnancy. Women had a lower prevalence of moderate to severe sRV dysfunction than men (21% vs 42.6%, p=0.001) despite similar ages. Beta-blockers (p=0.008), furosemide (p=0.012), and mineralocorticoid receptor antagonists (p=0.028) were less frequently prescribed to women than men. Women had fewer implantable cardioverter-defibrillators (ICDs) for primary prevention than men (3.7% vs 13.6%, p=0.016), with no difference in the prevalence of secondary prevention ICDs (1.2% vs 2.3%, p=1). The four women with a prohibitive maternal mortality risk (modified WHO class IV) complied with recommendations to avoid pregnancy. After excluding these 4 women, no differences regarding frequency of adverse cardiac events, age at the time of event, and proportion with moderate or severe sRV dysfunction were observed in women with (N=43) and without (N=35) pregnancies during 14 years of follow-up. Conclusions: Women with TGA and a sRV had a lower prevalence of moderate to severe systemic ventricular dysfunction than men, along with a lower proportion of primary prevention ICDs. Following risk assessment and counselling with contraindication of pregnancy in the highest risk subgroup, pregnancy had no impact on long-term cardiac outcomes.

Ventricular tachycardia ablation before an implantable cardioverter defibrillator in secondary prevention: is always the best option?

Abstract Background Among patients with an aborted episode of malignant ventricular arrhythmias without a reversible cause, the Implantable Cardioverter Defibrillator (ICD) is considered an important therapy for secondary prevention of sudden cardiac death (SCD). Some authors propose primary catheter ablation and deferred ICD implantation may be the preferred approach in patients with substrate-related ventricular tachycardia. Purpose We want to evaluate the need of secondary time ablation in patients with secondary prevention ICD, when submitted only a medical therapy after the index event. Methods We conducted a retrospective, observational study of 90 patients who consecutively implanted ICD after an aborted episode of malignant ventricular arrhythmias without a reversible/known cause between 2014 and 2020. Patients with Brugada Syndrome, Wolff-Parkinson-White syndrome, QT related diseases and previous ventricular tachycardia (VT) ablation were excluded. Baseline clinical characteristics were analyzed, and a 1-year follow-up was performed: cardiovascular (CV) death, sustain VT), ventricular fibrillation (VF), antitachycardia pacing (ATP), ICD shock, VT ablation. Results Mean age was 58±18 years, 80% (n=72) were male and 65.5% (n=59) had a non-ischemic etiology. Most of the patients (61%; n=56) present with hemodynamic unstable VT or syncope, and 38% (n=34) with SCD [most due to VF (n=30)]. After the index event 41.1% (n=37) and 83.8% (n=75) initiate antiarrhythmic and beta-blocker (BB), respectively. During 1-year follow-up (FUP) 11.1% (n=10) had a sustain VT and 2.2% (n=2) VF leading to ATP and appropriated shock in 11.1% (n=10) and 10% (n=9), respectively. There was 2 CV death [due to acute heart failure (HF)], 8 HF hospitalization and 3 VT ablation during follow-up. The presence of chronic kidney disease at baseline was the only parameter related to 1-year CV death (1.3% vs 18.2%, p=0.039) and HF hospitalization (0% vs 18.2%, p=0.014). The antiarrhythmic after index event was associated with a significant less sustain VT [10% vs 45%, OR 0.114 (IC 95% 0.014 to 0.927] and consequently ATP (adjusted for age) and had a numerical benefit in ICD shock (2.7% vs 15.1%, p=0.076) and need of a secondary time ablation (0% vs 5.7%, p=0.266). Conclusion The ICD implant with antiarrhythmic therapy, as a primary approach to secondary prevention (vs ablation), after an aborted episode of malignant ventricular arrhythmias still showed to be a secure and viable first option. Funding Acknowledgement Type of funding sources: None.

Defibrillation Threshold Testing and Long-term Follow-up in Chagas Disease.

Sudden cardiac death is the most common cause of death in chronic Chagas cardiomyopathy (CCC). Because most CCC patients who are candidates for implantable cardioverter-defibrillators (ICD) meet criteria for high defibrillation threshold values, a defibrillator threshold test (DTT) is suggested. We investigated the use of DTT in CCC patients, focusing on deaths related to ICD and arrhythmic events, as well as treatment during long-term follow-up. We retrospectively evaluated 133 CCC patients who received an ICD mainly for secondary prevention. Demographic, clinical, laboratory data, Rassi score, and DTT data were collected, with p < 0.05 considered significant. The mean patient age was 61 (SD, 13) years and 72% were men. The baseline left ventricular ejection fraction was 40 (SD, 15%) and the mean Rassi score was 10 (SD, 4). No deaths occurred during DTT and no ICD failures were documented. There was a relationship between higher baseline Rassi scores and higher DTT scores (ANOVA = 0.007). The mean time to first shock was 474 (SD, 628) days, although shock was only necessary for 28 (35%) patients with ventricular tachycardia, since most cases resolved spontaneously or through antitachycardia pacing. After a mean clinical follow-up of 1728 (SD, 1189) days, 43 deaths occurred, mainly related to progressive heart failure and sepsis. A routine DTT may not be necessary for CCC patients who receive an ICD for secondary prevention. High DTT values seem to be unusual and may be related to high Rassi scores.

Pacemaker implantation due to cardiac conduction disease in patients with subsequent cardiac sarcoidosis may be a marker of early disease and is associated with adverse 5-year clinical outcome

Abstract Background Sarcoidosis is a rare chronic granulomatous disease of unknown aetiology with potential multi-organ involvement and end-organ dysfunction. Cardiac sarcoidosis (CS) occurs in 5–10% of patients with sarcoidosis though an up to 25% prevalence has been reported by imaging and autopsy studies, suggesting undiagnosed silent disease. Progression of CS, especially if undiagnosed and untreated, may lead to heart failure, atrioventricular block (AVB), ventricular arrhythmias and sudden cardiac death. Aim We sought to determine whether signs of cardiac conduction disease (CCD) prior to the clinical diagnosis of sarcoidosis is associated with poor long-term prognosis in patients with imaging-confirmed cardiac involvement. Method All patients diagnosed with CS since January 1, 2000, at a tertiary centre (n=112) with either primary cardiac localisation (n=70) or cardiac involvement in otherwise primary non-cardiac sarcoidosis (n=42) as per imaging were included. Swedish pacemaker and ICD registry was used to identify patients who received cardiac implantable electronic device (CIED). CCD-related indications for CIED implant were defined as AVB, bi- or trifascicular block. Kaplan-Meier curve analysis and time-dependent Cox regression analysis were used for estimation of risk of death from any cause (primary endpoint), death or upgrade to cardiac resynchronization therapy (CRT, secondary endpoint) at 5 years after CS diagnosis, stratified for history of CIED implantation due to CCD. Hazard ratios were calculated in a univariate model and adjusted for age, gender and the use of implantable cardioverter-defibrillator (ICD). Results Mean age at CS diagnosis was 59±13 years (54% male). Forty-nine patients received CIED implant at a mean age of 54±13 years (14 pacemakers (29%), 14 primary prevention ICDs (29%), 13 secondary prevention ICDs (27%) and 8 CRT-D (16%)). The median time in years from CS diagnosis to CIED implant was for pacemaker −2.5 [IQR 8.5], primary ICD −0.3 [IQR 3.8], secondary ICD −4.0 [IQR 10.4] and CRT-D −0.03 [IQR 1.5]. CIED was implanted prior to CS diagnosis in 29 patients of whom 17 had CCD [MOU1] as the indication for implant. At 5-year follow-up in the CS cohort, 16 patients died and 2 underwent device upgrade to CRT (median 3.2 years [IQR 1.2]). CIED implant prior to CS diagnosis was associated with the primary (HRuni 3.5, 95% CI 1.2–10, p=0.021, Figure 1; HRadj 10.5, 95% CI 1.7–63, p=0.01) and the secondary (HR 3.5, 95% CI 1.2–10, p=0.019; HRadj 8.2, 95% CI 1.6–41.1, p=0.011) endpoints. Conclusion CIED implantation due to CCD can be an early manifestation of undiagnosed CS. It was observed in 15% of all patients with CS and was associated with adverse outcome. Identification of signs of CCD necessitating CIED implant in a middle-aged patient may motivate further diagnostic work-up aimed at timely detection of concealed CS. Funding Acknowledgement Type of funding sources: Foundation. Main funding source(s): Hjärt-Lung fondenAvtal om Läkarutbildning och Forskning

Posttraumatic stress disorder in pediatric patients with implantable cardioverter-defibrillators and their parents.

An implantable cardioverter-defibrillator (ICD) in the pediatric patient (and the precipitating events that led to ICD placement) can be traumatic for patients and their families and may lead to posttraumatic stress disorder (PTSD). This study aimed to estimate the prevalence of PTSD in pediatric patients with an ICD and their parents and identify the factors associated with PTSD incidence. Pediatric participants with an ICD aged 8-21 years and parents of children aged 0-21 years completed surveys that included demographic characteristics and PTSD measures. Pediatric participants completed additional psychosocial measures, such as anxiety and depression self-report questionnaires. Fifty youth (30% female) and 43 parents (70% female) completed the measures. Six of 50 youth (12%) met the screening criteria for a likely PTSD diagnosis, while 20 of 43 parents (47%) met the cutoff for PTSD on the screening measure. Children with PTSD were more likely to have had a secondary prevention ICD (83% vs 17%; P=.021), meet the clinical cutoff for depression (67% vs 16%; P= .005), and had higher shock anxiety scores (31.7 vs 17.9; P= .003) than children without PTSD. Female gender (57% vs 23%; P = .043) and patient depression (31% vs 5%; P = .042) were associated with PTSD in parents. Parents were found to be more likely to meet the criteria for PTSD than youth. In youth, PTSD was associated with medical and psychosocial factors, whereas PTSD in parents was associated with being female and child depression. Clinic-based screenings and management planning of emotional functioning are warranted to address psychological distress in patients and parents.

EP News: Allied Professionals

In this multcenter, international, randomized controlled trial, Tung et al (Circulation May 4, 2022; doi:10.1161/CIRCULATIONAHA.122.060039, PMID 35507499) sought to assess the efficacy of early catheter ablation of ventricular tachycardia (VT) at the time of implantable cardioverter-defibrillator (ICD) implantation as compared with conventional therapy. The Pan-Asia United States Prevention of Sudden Cardiac Death trial enrolled patients from centers in China, Japan, South Korea, and Taiwan who had structural heart disease (SHD) and an indication for secondary prevention ICD or who had VT inducible at the time of electrophysiology study (EPS) and met criteria for primary prevention ICD.

QRS fragmentation is associated with increased risk of ventricular arrhythmias in high-risk patients; Data from the SMASH 1 Study.

IntroductionQRS fragmentation (fQRS), defined as the presence of additional spikes within the QRS complex, has been associated with myocardial conduction abnormalities and arrhythmogenicity.ObjectiveWe aimed to assess whether fQRS is associated with incident ventricular arrhythmias (VA) in high‐risk patients treated with implantable cardioverter‐defibrillator (ICD) for primary and secondary prevention.MethodsIn a prospective observational multicenter study, we included 495 patients treated with ICD. fQRS was analyzed according to previously validated criteria, by two physicians blinded for outcome data. Incident VA were obtained from ICD recordings.ResultsECG recordings interpretable for fQRS were available in 459 patients (93%), aged 66 ± 12 years with left ventricular ejection fraction 40% ± 13%. fQRS was present in 52 patients (11%) with comparable baseline characteristics to patients without fQRS, except higher age, higher prevalence of coronary artery disease (CAD), lower prevalence of cardiomyopathy, and more frequently a secondary prevention ICD indication. Among patients with native QRS, those with fQRS had similar QRS duration and axis to those without fQRS. During 3.1 ± 0.7 years follow‐up, 126 patients (28%) had ≥1 VA . fQRS was associated with increased risk of VA (HR 3.41 [95% CI 2.27–5.13], p < .001), which persisted after adjusting for age, gender, sex, BMI, CAD, heart failure, renal function, ICD indication, QRS duration, QRS axis, Q waves, and bundle branch block. fQRS was more strongly associated with VA in patients with a primary (HR 6.05 [95% CI 3.16–11.60]) versus secondary (HR 2.39 [95% CI 1.41–4.04]) ICD indication (p‐for‐interaction = .047).ConclusionsfQRS is associated with threefold increased risk of VA in high‐risk patients, independent of established risk factors.

Implantable cardioverter-defibrillator therapy in the very young - Patient characteristics procedural outcome and one-year follow-up - A subgroup analysis of the german DEVICE registry

Abstract Funding Acknowledgements Type of funding sources: None. Background The implantable cardioverter-defibrillator (ICD) and cardiac resynchronization therapy defibrillator (CRT-D) are well-established and essential therapeutic pillars for patients with heart failure and survivors of sudden cardiac death. The number of young patients receiving ICD or CRT-D has been increasing in the last decades. Understanding the key differences between the typically older ICD population and younger patients is paramount to optimized patient care. Methods The DEVICE registry prospectively enrolled patients undergoing ICD/CRT implantation or revision from 50 German centers between 2007–2014. Data on patient characteristics, procedural outcome, adverse events and mortality during the initial stay and follow-up was collected. All patients under the age of 45 years were identified and included into a comparative analysis with the remaining population. Results A total number of 4181 patients were enrolled into the registry, of which 236 patients (5.6%) were under the age of 45 years. Median age was 38.0 [31.0; 42.0] vs. 69.0 [60.0; 75.0] years, p&amp;lt;0.001), compared to older patients. Young patients were more likely to receive an ICD (91.5 vs. 69.4%, p&amp;lt;0.001), than CRT device and were less likely to suffer from non-cardiac comorbidities (20.3 vs. 67.4%, p&amp;lt;0.001). Coronary artery disease was less common in young patients (15.7 vs. 63.6%, p&amp;lt;0.001), whereas hypertrophic cardiomyopathy (11.0 vs. 2.5%, p&amp;lt;0.001) and primary cardiac electrical diseases (14.0 vs. 1.6%, p&amp;lt; 0.001) were encountered more often. Mean left-ventricular ejection fractions were 42.4±18.5 vs. 31.5±11.8%, respectively (p&amp;lt;0.001) with less young patients in NYHA functional class III/IV (19.5 vs. 45.3%, p&amp;lt;0.001). Primary symptom at presentation was chronic heart failure for older patients (19.5 vs. 34.8%, p&amp;lt;0.001) and survived sudden cardiac death (30.9 vs. 15.6%, p&amp;lt;0.001) for young patients. Thus, ICD for secondary prevention was more common in young patients (53.8 vs. 43.2%, p&amp;lt;0.001). There were no detectable differences in postoperative complications (3.0 vs. 4.1%, p=0.500) or in-hospital mortality (0.0 vs. 0.3%, p=1.000). Median follow-up time was 514 [398; 669] vs. 458 [391; 563] days (p=0.006). Device-associated complications requiring revision were more common in young patients (16.3 vs. 8.2%, p&amp;lt;0.001) and all-cause 1-year-mortality after implantation was lower (3.1 vs. 7.3%, p=0.029; HR 0.42, 95%CI: 0.19-0.94). Even though there was no difference in rates of rehospitalization between groups (32.1 vs. 32.4%, p=0.93), young patients were re-admitted more often for "cardiac" reasons (82.7 vs. 58.9%, p&amp;lt;0.001). Conclusion Rates for procedural complications and in-hospital mortality were very low and without differences between both age groups. However younger patients experienced a higher rate of postoperative complications requiring revision and had higher readmission rates for cardiac reasons, potentially due to a more active lifestyle.

Improved prediction of electrical storm in patients with prior myocardial infarction and implantaImproved prediction of electrical storm in patients with prior myocardiable cardioverter defibrillator

Abstract Funding Acknowledgements Type of funding sources: None. Aims To evaluate predictors of electrical storm (ES), including chronic total occlusion in an infarct-related coronary artery (infarct-related artery CTO, IRACTO), in a cohort of patients with prior myocardial infarction (MI) and implantable cardioverter-defibrillators (ICD). Methods Multicenter observational cohort study including 643 consecutive patients with prior MI and a first ICD implanted between 2005 and 2018 at three tertiary hospitals. All the patients included in the study had undergone a diagnostic coronary angiography before ICD implantation. The variable prior ventricular arrhythmias (VA+) was positive in patients with secondary prevention ICDs and in those with at least one appropriate ICD therapy after primary prevention implantation. Results During a median follow-up of 42 months 59 patients (9%) suffered ES. The presence of at least one IRACTO not revascularized (IRACTO-NR) was associated with a significantly higher cumulative incidence of ES (14.5% vs 4.8%, p&amp;lt;0.001). IRACTO-NR maintained a significant association with ES after adjustment for potential confounders (HR 2.3, p=0.005) and was an independent predictor of ES together with VA+ and LVEF. The best cut-off of LVEF to predict ES was ≤38%. A risk-prediction model based on IRACTO-NR, VA+ and LVEF≤38% identified three categories of ES risk (low, intermediate and high), with progressively increasing cumulative incidence of ES (2.2%, 9% and 20%). Conclusion In a cohort of patients with prior MI and ICD, IRACTO-NR is an independent predictor of ES. A new risk-prediction model allowed the identification of three categories of risk, with potentially important clinical implications.