Implantable Cardioverter Defibrillator Discharges Research Articles

Cardiac MRI Pectoralis Muscle Thickness as a Measure of Sarcopenia: Prognostic Significance, Interreader Agreement, and Physiologic Correlation.

Purpose To evaluate pectoralis muscle thickness at routine cardiac MRI as a marker of sarcopenia, including prognostic significance for major adverse cardiac events (MACE), interobserver agreement, and correlation with physiologic parameters. Materials and Methods This retrospective cohort study included adult patients undergoing cardiac MRI for assessment of suspected cardiomyopathy between October 2018 and February 2020. Measurements of maximum pectoralis major thickness were performed by two experienced radiologists using axial images at the level of the carina. A random subset of 50 patients were re-evaluated to assess intra- and interobserver agreement. The primary end point was MACE, defined as a composite of cardiac death, resuscitated sudden cardiac death, appropriate implantable cardioverter defibrillator discharge, or hospitalization for heart failure. Prognostic significance of pectoralis major thickness measurements for MACE was assessed using Cox proportional hazard models, and correlation between muscle thickness measurements and cardiopulmonary exercise testing (CPET), performed within 1 year of MRI, was assessed using Spearman correlation. Results The study included 1045 patients (mean age, 50 years ± 17 [SD]; 642 male, 403 female). After median follow-up of 3.3 years (IQR: 2.3-3.9 years), MACE occurred in 66 patients. In multivariable models adjusted for patient age, left ventricular ejection fraction, late gadolinium enhancement, and cardiomyopathy cause, pectoralis major muscle thickness was predictive of MACE in both male (hazard ratio [HR], 0.89 [95% CI: 0.85, 0.94]; P < .001) and female patients (HR, 0.85 [95% CI: 0.76, 0.96]; P = .008), with improved model fit in nested models. Pectoralis muscle thickness measurements had excellent intra- and interobserver agreement (intraclass correlation coefficient, 0.99 and 0.95, respectively) and correlated with absolute peak oxygen uptake (r = 0.65, P < .0001) and oxygen uptake efficiency slope (r = 0.61, P < .001) in the subset who underwent CPET within 1 year of MRI (n = 258). Conclusion Pectoralis major muscle thickness at routine cardiac MRI is a simple, reproducible measure of sarcopenia that was associated with MACE occurrence in male and female patients and correlated with CPET parameters. Keywords: Cardiac, Cardiomyopathies, MR Imaging Supplemental material is available for this article. © RSNA, 2024.

Contemporary Management and Prognostic Factors of Arrhythmia Recurrence in Patients with High-Energy Discharge of Cardiac Implantable Electronic Devices.

Background and Objectives: Understanding the underlying causes of implantable cardioverter-defibrillator (ICD) discharges is vital for effective management. This study aimed to evaluate the characteristics of patients admitted following ICD discharge, focusing on myocardial ischemia as a potential exacerbating factor and potential risk factors for VT recurrence. Materials and Methods: This retrospective, single-center study included 81 patients with high energy discharge from cardiac implantable electronic device admitted urgently to the cardiology department from 2015 to 2022. The exclusion criterion was ST-segment elevation acute coronary syndrome. Data were collected anonymously from electronic medical records. Patients were categorized based on coronary angiography, percutaneous angioplasty, presence of significant stenosis, recurrent ventricular tachycardia (VT), and catheter ablation. Clinical variables, including demographic data, echocardiographic parameters, and pharmacotherapy, were analyzed. The primary endpoint was the recurrence of VT during in-hospital stay. Results: Among 81 patients, predominantly male (86.4%), with a mean age of 63.6 years, 55 (67.9%) had coronary artery disease (CAD) as the primary etiology for ICD implantation. Coronary angiography was performed in 34 patients (42.0%) and showed significant stenosis (>50%) in 18 (41.8%) patients, while 8 (26.0%) individuals underwent percutaneous coronary intervention (PCI). Recurrent VT occurred in 21 subjects (26.3%), while ventricular catheter ablation was performed in 36 patients (44.0%). Referral for urgent coronary angiography was associated with presence of diabetes (p = 0.028) and hyperlipidemia (p = 0.022). Logistic regression analysis confirmed NYHA symptomatic class (OR 4.63, p = 0.04) and LVH (OR 10.59, p = 0.049) were independently associated with relapse of VT. CAD patients underwent catheter ablation more frequently (p = 0.001) than those with dilated cardiomyopathy. Conclusions: The study showed a low referral rate for coronary angiography among patients with ICD discharge. Presence of LVH and preexisting symptomatic class influence arrhythmia recurrence. Understanding these associations can guide personalized management strategies for ICD recipients.

Dosing and Safety Profile of Aficamten in Symptomatic Obstructive Hypertrophic Cardiomyopathy: Results From SEQUOIA-HCM.

Aficamten, a novel cardiac myosin inhibitor, reversibly reduces cardiac hypercontractility in obstructive hypertrophic cardiomyopathy. We present a prespecified analysis of the pharmacokinetics, pharmacodynamics, and safety of aficamten in SEQUOIA-HCM (Safety, Efficacy, and Quantitative Understanding of Obstruction Impact of Aficamten in HCM). A total of 282 patients with obstructive hypertrophic cardiomyopathy were randomized 1:1 to daily aficamten (5-20 mg) or placebo between February 1, 2022, and May 15, 2023. Aficamten dosing targeted the lowest effective dose for achieving site-interpreted Valsalva left ventricular outflow tract gradient <30 mm Hg with left ventricular ejection fraction (LVEF) ≥50%. End points were evaluated during titration (day 1 to week 8), maintenance (weeks 8-24), and washout (weeks 24-28), and included major adverse cardiac events, new-onset atrial fibrillation, implantable cardioverter-defibrillator discharges, LVEF <50%, and treatment-emergent adverse events. At week 8, 3.6%, 12.9%, 35%, and 48.6% of patients achieved 5-, 10-, 15-, and 20-mg doses, respectively. Baseline characteristics were similar across groups. Aficamten concentration increased by dose and remained stable during maintenance. During the treatment period, LVEF decreased by -0.9% (95% CI, -1.3 to -0.6) per 100 ng/mL aficamten exposure. Seven (4.9%) patients taking aficamten underwent per-protocol dose reduction for site-interpreted LVEF <50%. There were no treatment interruptions or heart failure worsening for LVEF <50%. No major adverse cardiovascular events were associated with aficamten, and treatment-emergent adverse events were similar between treatment groups, including atrial fibrillation. A site-based dosing algorithm targeting the lowest effective aficamten dose reduced left ventricular outflow tract gradient with a favorable safety profile throughout SEQUOIA-HCM. URL: https://www.clinicaltrials.gov; Unique Identifier: NCT05186818.

Cardiac sympathetic activity and lethal arrhythmic events: insight into bell-shaped relationship between 123I-meta-iodobenzylguanidine activity and event rates

Background123I-meta-iodobenzylguanidine (mIBG) has been applied to patients with chronic heart failure (CHF). However, the relationship between 123I-mIBG activity and lethal arrhythmic events (ArE) is not well defined. This study aimed to determine this relationship in Japanese and European cohorts.ResultsWe calculated heart-to-mediastinum (H/M) count ratios and washout rates (WRs) of 827 patients using planar 123I-mIBG imaging. We defined ArEs as sudden cardiac death, arrhythmic death, and potentially lethal events such as sustained ventricular tachycardia, cardiac arrest with resuscitation, and appropriate implantable cardioverter defibrillator (ICD) discharge, either from a single ICD or as part of a cardiac resynchronization therapy device (CRTD). We analyzed the incidence of ArE with respect to H/M ratios, WRs and New York Heart Association (NYHA) functional classes among Japanese (J; n = 581) and European (E; n = 246) cohorts. We also simulated ArE rates versus H/M ratios under specific conditions using a machine-learning model incorporating 13 clinical variables. Consecutive patients with CHF were selected in group J, whereas group E comprised candidates for cardiac electronic devices. Groups J and E mostly comprised patients with NYHA functional classes I/II (95%) and II/III (91%), respectively, and 21% and 72% were respectively implanted with ICD/CRTD devices. The ArE rate increased with lower H/M ratios in group J, but the relationship was bell-shaped, with a high ArE rate within the intermediate H/M range, in group E. This bell-shaped curve was also evident in patients with NYHA classes II/III in the combined J and E groups, particularly in those with a high (> 15%) mIBG WR and with ischemic, but not in those with non-ischemic etiologies. Machine learning-based prediction of ArE risk aligned with these findings, indicating a bell-shaped curve in NYHA class II/III but not in class I.ConclusionsThe relationship between cardiac 123I-mIBG activity and lethal arrhythmic events is influenced by the background of patients. The bell-shaped relationship in NYHA classes II/III, high WR, and ischemic etiology likely aids in identifying patients at high risk for ArEs.

Right Ventricular Strain Derived from Cardiac MRI Feature Tracking for the Diagnosis and Prognosis of Arrhythmogenic Right Ventricular Cardiomyopathy.

Purpose To demonstrate the myocardial strain characteristics of patients with arrhythmogenic right ventricular cardiomyopathy (ARVC), based on revised Task Force Criteria (rTFC), and to explore the prognostic value of strain analysis in ARVC. Materials and Methods This retrospective study included 247 patients (median age, 38 years [IQR, 28-48 years]; 167 male, 80 female) diagnosed with ARVC, based on rTFC, between 2014 and 2018. Patients were divided into "possible" (n =25), "borderline" (n = 40), and "definite" (n = 182) ARVC groups following rTFC. Biventricular global strain parameters were calculated using cardiac MRI feature tracking (FT). The primary outcome was defined as a composite of cardiovascular events, including cardiovascular death, heart transplantation, and appropriate implantable cardioverter defibrillator discharge. Univariable and multivariable cumulative logistic regression and Cox proportional hazards regression analysis were used to evaluate the diagnostic and prognostic value of right ventricle (RV) strain parameters. Results Patients with definite ARVC had significantly reduced RV global strain in all three directions compared with possible or borderline groups (all P < .001). RV global longitudinal strain (GLS) was an independent predictor for disease (odds ratio, 1.09 [95% CI: 1.02, 1.16]; P = .009). During a median follow-up of 3.4 years (IQR, 2.0-4.9 years), 55 patients developed primary end point events. Multivariable analysis showed that RV GLS was independently associated with the occurrence of cardiovascular events (hazard ratio, 1.15 [95% CI: 1.07, 1.24]; P < .001). Kaplan-Meier analysis showed that patients with RV GLS worse than median had a higher risk of combined cardiovascular events (log-rank P < .001). Conclusion RV GLS derived from cardiac MRI FT demonstrated good diagnostic and prognostic value in ARVC. Keywords: MR Imaging, Image Postprocessing, Cardiac, Right Ventricle, Cardiomyopathies, Arrhythmogenic Right Ventricular Cardiomyopathy, Revised Task Force Criteria, Cardiovascular MR, Feature Tracking, Cardiovascular Events Supplemental material is available for this article. © RSNA, 2024.

Clinical significance and genetic basis of hypertrophic cardiomyopathy with apical phenotype: comparison of pure-apical form and distal-dominant form

Abstract Background Apical hypertrophic cardiomyopathy (apical HCM) is a variant of HCM first reported in Japan. The definition of apical HCM in the Japanese Circulation Society guideline is left ventricular hypertrophy limited to the level of the apex below the papillary muscle level. On the other hand, apical HCM in Western countries often includes hypertrophy that extends to the ventricular septum beyond the true LV apex. Although these variations may have different clinical characteristics and prognoses, they are often considered the same. Therefore, we previously proposed two phenotypes of apical HCM. Pure-apical form follows the definition of the JCS guideline. Distal-dominant form is defined as demonstrating apical hypertrophy extended to the ventricular septum without basal septal hypertrophy. However, the clinical significance and genetic basis of these phenotypes have not been reported. This study aimed to clarify clinical differences and yield of genetic testing in apical phenotype of HCM. Methods Regarding clinical presentation and prognosis, we retrospectively investigated 111 consecutive HCM patients with apical phenotype. HCM-related adverse events were defined as HCM-related death and nonfatal HCM-related events: heart failure admission, embolic stroke admission, and sustained ventricular tachycardia with hemodynamic instability or appropriate implantable cardioverter-defibrillator discharge. Furthermore, we performed a genetic analysis including 145 genes associated with cardiomyopathy in 69 unrelated patients within the cohort. Results In the cohort, 60 patients were pure-apical, and 51 were distal-dominant. The age at diagnosis was about 60 years, and the majority were male in both groups. The comorbidity rate of hypertension did not indicate a statistically significant difference. During the follow-up period of 10.3 ± 6.9 years, the occurrence of HCM-related adverse events was significantly higher in the distal-dominant group than in the pure-apical group (log-rank p=0.007). Detection rate of pathogenic or likely pathogenic variants in sarcomeric protein-encoding genes was significantly higher in the distal-dominant group than in the pure-apical group (21% vs. 3%; p=0.044). Conclusions Two phenotypes of apical HCM should be recognized and distinguished clinically because they have different prognoses and genetic features.

Fatal Arrhythmic Risks in Cardiac Sarcoidosis With Mildly Impaired Cardiac Function

BackgroundThe prognosis and later fatal arrhythmia in cardiac sarcoidosis (CS) with relatively preserved cardiac function were unclear. ObjectivesThis study aimed to evaluate the prognosis and arrhythmic events in patients with CS and mildly impaired cardiac function. MethodsData were collected from a nationwide Japanese cohort survey conducted in 57 hospitals (n = 420); 322 patients with CS with left ventricular ejection fraction (LVEF) >35% were investigated. ResultsVentricular tachycardia (VT) manifestation was present in 50 patients (16%) and absent in 272 (84%), of whom 36 (72%) and 46 (17%), respectively, had an implantable cardioverter-defibrillator (ICD). Over a median of 5 years, 23 all-cause deaths and 31 appropriate ICD discharges were observed. In Kaplan-Meier analysis, all-cause death did not differ between patients with and without VT manifestation (P = 0.660), although appropriate ICD therapy was significantly less used in patients without VT manifestation than in those with VT manifestation (P < 0.001). Of the 272 patients without VT manifestation, 18 had ventricular arrhythmic events (VAEs), including 3 sudden cardiac deaths and 15 appropriate ICD discharges. In multivariate analysis, concomitant nonsustained ventricular tachycardia (NSVT) with atrioventricular block (AVB), lower LVEF, abnormal gallium-67 scintigraphy or 18F-fluorodeoxyglucose positron emission tomography of the heart (Ga/PET), and concomitant NSVT with abnormal Ga/PET at CS diagnosis were independent predictors of VAEs (P = 0.008, P = 0.021, P = 0.049, and P = 0.024, respectively). ConclusionsIf concomitant NSVT with AVB, concomitant NSVT with abnormal Ga/PET, or abnormal Ga/PET is observed in patients with CS and mildly impaired cardiac function (LVEF >35%), ICD should be considered as primary prevention.

Incremental significance of myocardial oedema for prognosis in hypertrophic cardiomyopathy.

To explore the prognosis of myocardial oedema measured by T2 mapping in hypertrophic cardiomyopathy (HCM). A total of 674 patients with HCM (age: 50 ± 15 years, 60.5% males) who underwent cardiovascular magnetic resonance were prospectively enrolled from 2011 to 2020. One hundred healthy controls (age: 48 ± 19 years, 58.0% males) were included for comparison. Myocardial oedema was quantitatively measured by T2 mapping in both global and segmental myocardium. The endpoints were defined as a combination of cardiovascular death and appropriate implantable cardioverter defibrillator discharge. During a median follow-up of 36 months (interquartile range: 24-60 months), 55 patients (8.2%) had cardiovascular events. Patients with cardiovascular events had a higher T2 max, T2 min, and T2 global values (all P < 0.001) than patients who remained event free. Survival analysis demonstrated that patients with HCM with late gadolinium enhancement [LGE(+)] and T2 max ≥44.9 ms had a higher risk of developing cardiovascular events (P < 0.001). A multivariate Cox regression analysis showed that T2 max, T2 min, and T2 global provided significant prognostic value to predict cardiovascular events (all P < 0.001). According to the C-index (0.825, 0.814), net reclassification index (0.612, 0.536, both P < 0.001), and integrative discrimination index (0.029, 0.029, both P < 0.05), T2 max or T2 min significantly increased the predictive performance of established risk factors, including extensive LGE. Patients with HCM with LGE(+) and higher T2 had worse prognosis than those with LGE(+) and lower T2.

High-Sensitivity Cardiac Troponin T Elevation in Hypertrophic Cardiomyopathy Is Associated With Ventricular Arrhythmias

ObjectiveTo investigate the relationship between high-sensitivity cardiac troponin T (hs-cTnT) levels and sudden cardiac death (SCD) in patients with hypertrophic cardiomyopathy (HCM). MethodsA referral HCM population with prospectively obtained hs-cTnT concentration from March 1, 2018, to April 23, 2020, was reviewed. Patients with end-stage renal disease or an abnormal hs-cTnT level not collected in an outpatient protocolled fashion were excluded. The hs-cTnT level was compared with demographic characteristics, comorbidities, conventional HCM-associated SCD risk factors, imaging, exercise testing, and prior cardiac events. ResultsOf 112 included patients, 69 (62%) had an elevated hs-cTnT concentration. The level of hs-cTnT correlated with known risk factors for SCD, including nonsustained ventricular tachycardia (P=.049) and septal thickness (P=.02). When patients were stratified by having a normal vs an elevated hs-cTnT concentration, patients with elevated hs-cTnT concentration were more likely to have experienced an implantable cardioverter-defibrillator discharge for ventricular arrhythmia, ventricular arrhythmia with hemodynamic instability, or cardiac arrest (incidence rate ratio, 2.96; 95% CI, 1.11 to 10.2). When sex-specific hs-cTnT cutoffs were removed, this association was no longer present (incidence rate ratio, 1.50; 95% CI, 0.66 to 3.60). ConclusionIn a protocolized, outpatient HCM population, hs-cTnT elevations were common and were associated with more arrhythmic expressivity of the HCM substrate as indicated by previous ventricular arrhythmias and appropriate implantable cardioverter-defibrillator shocks only when sex-specific hs-cTnT cutoffs were used. Further research should use different hs-cTnT reference values by sex to determine whether an elevated hs-cTnT value is an independent risk factor for SCD in patients with HCM.

Incremental prognostic value of left atrial and biventricular feature tracking in dilated cardiomyopathy: a long-term study

BackgroundDespite the use of cardiovascular magnetic resonance (CMR) feature tracking (FT) imaging to detect myocardial deformation, the optimal strain index in dilated cardiomyopathy (DCM) is unclear. This study aimed to determine whether atrial and biventricular strains can provide the greatest or joint incremental prognostic value in patients with DCM over a long follow-up period. MethodsFour hundred-twelve DCM patients were included retrospectively. Comprehensive clinical evaluation and imaging investigations were obtained, including measurements of CMR-FT derived left atrial (LA) reservoir, conduit, booster strain (εs, εe, εa); left ventricular (LV) and right ventricular (RV) global longitudinal, radial, circumferential strain (GLS, GRS, GCS). All patients were followed up for major adverse cardiac events (MACE) including all-cause mortality, heart transplantation, and implantable cardioverter defibrillator discharge. The predictors of MACE were examined with univariable and multivariable Cox regression analysis. Subsequently, nested Cox regression models were built to evaluate the incremental prognostic value of strain parameters. The incremental predictive power of strain parameters was assessed by Omnibus tests, and the model performance and discrimination were evaluated by Harrell C-index and integrated discrimination improvement (IDI) analysis. Patient survival was illustrated by Kaplan–Meier curves and differences were evaluated by log-rank test. ResultsDuring a median follow-up of 5.0 years, MACE were identified in 149 (36%) patients. LAεe, LVGLS, and RVGLS were the most predictive strain parameters for MACE (AUC: 0.854, 0.733, 0.733, respectively). Cox regression models showed that the predictive value of LAεe was independent from and incremental to LVGLS, RVGLS, and baseline variables (HR 0.74, 95% CI 0.68–0.81, P < 0.001). In reclassification analysis, the addition of LAεe provided the best discrimination of the model (χ2 223.34, P < 0.001; C-index 0.833; IDI 0.090, P < 0.001) compared with LVGLS and RVGLS models. Moreover, LAεe with a cutoff of 5.3% further discriminated the survival probability in subgroups of patients with positive LGE or reduced LVEF (all log-rank P < 0.001). ConclusionLAεe provided the best prognostic value over biventricular strains and added incremental value to conventional clinical predictors for patients with DCM.

Single beta-blocker or combined amiodarone therapy in implantable cardioverter-defibrillator and cardiac resynchronization therapy—defibrillator patients: Insights from the German DEVICE registry

Because of its antiarrhythmic potency and due to the lack of alternatives, amiodarone is often used for antiarrhythmic therapy in patients with implantable cardioverter-defibrillator (ICD) or cardiac resynchronization therapy-defibrillator systems. To date, robust data on the safety and clinical benefit of amiodarone therapy in these patients are missing. The purpose of this study was to assess the periprocedural and postprocedural outcomes of combined therapy with beta-blockers plus amiodarone compared to treatment with single beta-blockers in the "real-life" cohort of ICD recipients of the German DEVICE registry. A total of 4499 patients who underwent ICD implantation, revision, or upgrade in 49 centers participating in the German DEVICE registry were enrolled from March 2007 to February2014. Amiodarone had no significant effect on the success of defibrillation testing. Early implantation-associated complications were similar between the groups. However, 1-year overall mortality was significantly higher in the beta-blocker plus amiodarone cohort (adjusted hazard ratio 2.09; P <.001). Interestingly, among the surviving patients, amiodarone was not associated with a significantly reduced risk of ICD discharges or syncopal events. Furthermore, the occurrence of ventricular tachycardia (VT) storm or incessant VTs and the number of patients scheduled for intracardiac ablation did not differ among both groups, whereas the rate of rehospitalization was lower in the cohort with only beta-blockers. Although amiodarone has no adverse effect on the success of defibrillation testing, our data suggest an increased all-cause mortality under amiodarone therapy, especially in the subgroups of patients with sinus rhythm or severely reduced left ventricular function. In surviving patients, rates of arrhythmic events were comparable.

Abstract 11615: The Prevalence and Association of Exercise Test Abnormalities With Sudden Cardiac Death and Transplant-Free Survival in Childhood Hypertrophic Cardiomyopathy

Introduction: Hypertrophic cardiomyopathy (HCM) can be associated with an abnormal exercise response. In adults with HCM, an abnormal exercise stress test (EST) is predictive of heart failure outcomes. Our goal was to determine if an abnormal exercise response is associated with adverse outcomes in pediatric HCM patients. Methods: : In an international cohort study with 20 centers (PRIMaCY), children &lt;18 years with primary HCM were included. Abnormal EST was defined as an abnormal heart rate or blood pressure response, arrhythmias and/or ischemic ECG changes on exercise. Sudden cardiac death (SCD) events were defined as a composite of SCD and aborted SCD including appropriate implantable cardioverter defibrillator discharges. Using Kaplan-Meier survival analyses, we analyzed the association of abnormal EST with SCD and transplant-free survival. Results: Of 724 eligible patients, 604 underwent at least one EST on follow-up. There were no differences in clinical characteristics between those with or without an EST. The median age at EST was 13.8yrs (IQR 11.0-15.7yrs), 76% were male, 55% were on beta-blockers. 299 (49.5%) had an abnormal EST. Patients with an abnormal EST had more severe septal hypertrophy, higher left atrial diameter z-scores, higher resting LV outflow gradient at first evaluation, and a higher proportion were genotype-positive (p&lt;0.05) compared to those with a normal EST. An abnormal EST was associated with lower 5-year transplant-free survival (99% vs. 95%, p=0.0082) and lower 5-year freedom from SCD events (96% vs. 92%, p=0.025) (Figure 1). Conclusions: Exercise abnormalities are common in childhood HCM. An abnormal EST in children with HCM was associated with lower transplant-free survival and more SCD events. Further analysis will determine if the inclusion of EST results can increase the predictive accuracy of current pediatric SCD risk prediction models.

Prediction of Sudden Cardiac Arrest After Alcohol Septal Ablation for Hypertrophic Obstructive Cardiomyopathy: ASA-SCARRE Risk Score

This study aimed to derive a new score, the Alcohol Septal Ablation-Sudden Cardiac ARREst (ASA-SCARRE) risk score, that can be easily used to evaluate the risk of sudden cardiac arrest events (sudden cardiac death, resuscitation, or appropriate implantable cardioverter-defibrillator discharge) after alcohol septal ablation (ASA) in patients with hypertrophic obstructive cardiomyopathy. We analyzed 1,834 patients from the Euro-ASA registry (49% men, mean age 57 ± 14years) who were followed up for 5.0 ± 4.3years (9,202 patient-years) after ASA. A total of 65 patients (3.5%) experienced sudden cardiac arrest events, translating to 0.72 events per 100 patient-years. The independent predictors of sudden cardiac arrest events were septum thickness before ASA (hazard ratio 1.09 per 1mm, 95% confidence interval 1.04 to 1.14, p <0.001) and left ventricular outflow tract (LVOT) gradient at the last clinical checkup (hazard ratio 1.01 per 1mm Hg, 95% confidence interval 1.01 to 1.02, p=0.002). The following ASA-SCARRE risk scores were derived and independently predicted long-term risk of sudden cardiac arrest events: "0" for both LVOT gradient <30mmHg and baseline septum thickness <20mm; "1" for LVOT gradient ≥30mm Hg or baseline septum thickness ≥20mm; and "2" for both LVOT gradient ≥30mm Hg and baseline septum thickness ≥20mm. The C statistic of the ASA-SCARRE risk score was 0.684 (SE 0.030). In conclusion, the ASA-SCARRE risk score may be a useful and easily available clinical tool to predict risk of sudden cardiac arrest events after ASA in patients with hypertrophic obstructive cardiomyopathy.

Effects of renal denervation therapy on cardiac function and malignant arrhythmia in patients with reduced left ventricular ejection fraction and narrow QRS complexes treated with implantable cardioverter defibrillator.

Objective : The purpose of this study was to explore the effects of renal denervation (RDN) on cardiac function and malignant arrhythmia in patients with reduced left ventricular ejection fraction (HFrEF) and narrow QRS treated with an implantable cardioverter defibrillator (ICD). Methods: A total of 20 eligible HFrEF patients [left ventricular ejection fraction (LVEF) <40%] and narrow QRS complexes (QRS duration <120 ms) were randomized into either the ICD plus RDN group or the ICD only group during 17 April 2014 to 22 November 2016. Clinical data, including clinical characteristics, blood biochemistry, B-type natriuretic peptide, echocardiographic indexes, 6-min walk distance (6MWD), New York Heart Association (NYHA) classification, and count of ICD discharge events before and after the operation were analyzed. Patients were followed up for up to 3 years post ICD or ICD plus RDN. Results: Baseline clinical data were comparable between the two groups. Higher LVEF (%) (mixed model repeated measure, p = 0.0306) (39.50% ± 9.63% vs. 31.20% ± 4.52% at 1 year; 41.57% ± 9.62% vs. 31.40% ± 8.14% at 3 years), systolic blood pressure (p = 0.0356), and longer 6MWD (p < 0.0001) as well as reduction of NYHA classification (p < 0.0001) were evidenced in the ICD plus RDN group compared to ICD only group during follow-up. Patients in the ICD plus RDN group experienced fewer ICD discharge events (2 vs. 40) and decreased diuretic use; rehospitalization rate (30% vs. 100%, p = 0.0031) and cardiogenic mortality rate (0% vs. 50%, p = 0.0325) were also significantly lower in the ICD plus RDN group than in the ICD only group during follow-up. Conclusion: ICD implantation plus RDN could significantly improve cardiac function and cardiac outcome as well as increase exercise capacity compared to ICD only for HFrEF patients with narrow QRS complexes.

Does sports participation increase risk in patients with long QT syndrome? Results from a large French cohort.

Sports practice, especially in competition, is usually restrained in patients diagnosed with long QT syndrome (LQTS). Although data are scarce, a low incidence of cardiac arrhythmic events (CAEs) during sports practice is reported. We aim to evaluate the incidence of CAE during sports practice in LQTS patients. All consecutive patients above 18 years of age diagnosed with LQTS and prospectively followed at the referral centre for inherited arrhythmia syndrome received a survey to retrospectively assess their sports practice prior to and after the diagnosis of LQTS. Two hundred and forty-six patients were included (57% females). The median age was 43 years, and the median QTc was 457 ms (428; 482). Patients reported a total of 4092 years [1376 (34%) after diagnosis] of sports practice: 2905 (77%) [1138 (39%) after diagnosis] years of leisure practice and 1187 (23%) [238 (20%) after diagnosis] years of competitive practice. One hundred and eighty (73%) patients practiced sport prior to the diagnosis of LQTS and 170 (69%) after. Prior to the diagnosis, four (2%) patients presented a CAE during leisure sports practice and one during competition. After diagnosis, only one patient presented a CAE, appropriately treated by an implantable cardioverter defibrillator discharge, in the context of beta-blocker non-compliance. The CAE event rate was 0.0007 events/year in the 1376 years of total sports practice after the diagnosis of LQTS. After the diagnosis of LQTS, the occurrence of CAE is very low during sports practice, even in competitive practice. There was no CAE in patients properly treated with beta-blocker therapy with good compliance.

Very long-term prognosis in patients with hypertrophic cardiomyopathy: a longitudinal study with a period of 20years.

AimsWe aim to clarify the prognosis on patients with hypertrophic cardiomyopathy (HCM) for a follow‐up period of more than 10 years.Methods and resultsWe retrospectively analysed 102 consecutive patients with HCM diagnosed by 31 December 2000. Complete and detailed clinical records were obtained for 93 (91%) of the 102 patients. Sixty‐three (68%) of the 93 patients were men, and the mean age of the patients at the initial evaluation was 51.5 ± 13.0 years. During the mean follow‐up period of 19.6 ± 8.1 years (median 20.1 years), HCM‐related deaths occurred in 20 patients (21% [1.1%/year]). HCM‐related adverse events (including HCM‐related deaths and nonfatal HCM‐related events: hospitalization for heart failure, embolic stroke admission, and sustained ventricular tachycardia with haemodynamic instability or appropriate implantable cardioverter‐defibrillator discharge) occurred in 45 patients (48%). The first HCM‐related adverse events occurred in approximately 20% of the patients in every decade, the first decade to the third decade, from the initial evaluation. Forty‐seven patients (51%) had documentation of atrial fibrillation at the last follow‐up. There were seven patients in the end‐stage HCM group at the initial evaluation, and 22 patients (24%) had progression to end‐stage HCM during the follow‐up period.ConclusionsIn our cohort of patients, HCM‐related mortality was relatively favourable. However, approximately half of the patients suffered from HCM‐related adverse events during the follow‐up period of 20 years. It is important for HCM patients to be carefully followed up over the long‐term because HCM is a lifelong disease.

Outcomes of implantable cardioverter-defibrillator implantation in HIV-infected patients: A single-center retrospective cohort study.

BackgroundHIV‐infected individuals have a known increased risk of sudden cardiac death (SCD) compared to uninfected individuals. Implantable cardioverter‐defibrillators (ICDs) are standard therapy for preventing SCD; however, there is limited data on the outcomes of ICDs in HIV‐infected individuals.HypothesisHIV‐infected subjects receive a higher number of appropriate ICD therapies than uninfected controls.MethodsThis is a retrospective cohort study of 35 consecutive HIV‐Infected patients and 36 uninfected controls matched by age, race, and gender who were treated at the University of North Carolina Medical Center in the outpatient or inpatient setting from 2014 to the present and had undergone ICD implantation. For HIV‐infected subjects, a multivariate Poisson regression analysis was performed to evaluate the association between covariates and ICD therapies.ResultsAmong HIV‐infected subjects, the mean CD4 count was 582.5 cells/mm3 and 69% had an undetectable viral load. The median follow‐up was 6.4 years. HIV‐infected subjects had both a higher number of appropriate ICD shocks or antitachycardia pacing (ATP) therapy per person‐year as well as a higher number of inappropriate ICD shocks per person‐year than uninfected controls (1.512 vs. 0.590 and 0.122 vs. 0.0166, respectively, p < .001 for both comparisons). After multivariate adjustment, the presence of detectable/unsuppressed viral load at the time of ICD implantation was an independent predictor of both of the following in HIV‐infected subjects: (1) appropriate ICD discharge (p = .004), and (2) appropriate ICD discharge or appropriate ATP therapy (p < .001).ConclusionHIV‐infected subjects had a higher number of appropriate ICD discharge or ATP therapy per person‐year than matched uninfected controls.

Genetic Diagnostics Contribute to the Risk Stratification for Major Arrhythmic Events in Pediatric Patients with Long QT Syndrome Type 1–3

Long QT syndrome (LQTS) is an inherited arrhythmic disorder associated with sudden cardiac death (SCD). This study aimed to identify the clinical and molecular genetic risk factors that contribute to major arrhythmic events (MAEs) in patients with genetically confirmed childhood onset LQTS 1–3. This study was a retrospective double-center study. An MAE was defined as the occurrence of SCD, aborted SCD, appropriate implantable cardioverter defibrillator discharge, or sustained ventricular tachycardia. During a median follow-up of 4.6 years (range 0.1–24.3 years), MAEs occurred in 18 (17.8%) of 101 patients diagnosed with LQTS at a median of 7.7 years (range 0.0–18.0 years) despite the use of beta-blockers in 91.6% of patients at the last follow-up. A multivariate analysis identified a genetic diagnosis of LQTS2 and LQTS3 and variants within the KCNH2 S5-loop-S6 pore region as independent risk factors for MAEs, independent of the QTc value or a history of syncope detected from a univariate analysis. MAEs occur frequently in childhood onset LQTS despite beta-blocker treatment. A detailed molecular genetic diagnosis can contribute to the arrhythmia risk stratification and optimize the use of preventive measures in this vulnerable patient population.

Thoracoscopic sympathectomy decreases disease burden in patients with medically refractory ventricular arrhythmias.

OBJECTIVESThoracic sympathectomy has been shown to be effective in reducing implantable cardioverter-defibrillator (ICD) shocks and ventricular tachycardia recurrence in patients with channelopathies, but the evidence supporting its use for refractory ventricular arrhythmias in patients without channelopathies is limited. This is a single-centre cohort study of bilateral R1–R4 thoracoscopic sympathectomy for medically refractory ventricular arrhythmias.METHODSClinical information was examined for all bilateral thoracoscopic R1–R4 sympathectomies for ventricular arrhythmias at our institution from 2016 through 2020.RESULTSThirteen patients underwent bilateral thoracoscopic R1–R4 sympathectomy. All patients had prior ICD implant. Patients had a recent history of multiple ICD discharges (12/13), catheter ablation (10/13) and cardiac arrest (3/13). Ten patients were urgently operated on following transfer to our centre for sustained ventricular tachycardia. Seven patients had ventricular tachycardia ablations preoperatively during the same admission. Five patients were in intensive care immediately preoperatively, with 3 requiring mechanical ventilation. Three patients suffered in-hospital mortality. Kaplan–Meier analysis estimated 73% overall survival at 24-month follow-up. Among the 10 patients who survived to discharge, all were alive at a median follow-up of 8.7 months (interquartile range 0.6–26.7 months). Six of 10 patients had no further ICD discharges. Kaplan–Meier analysis estimated 27% ICD shock-free survival at 24 months follow-up for all patients. Three of 10 patients had additional ablations, while 2 patients underwent cardiac transplantation.CONCLUSIONSBilateral thoracoscopic sympathectomy is an effective option for patients with life-threatening ventricular arrhythmia refractory to pharmacotherapy and catheter ablation.

The clinical characteristics of patients admitted to the emergency department because of implantable cardioverter defibrillator shock

Aim: To present the clinical spectrum of the Emergency Department (ED) patients with presumed electrical shocks. Material and methods: The electronic recordings of the patients admitted to the ED of Unversity Hospital in Wroclaw between April 2020 and June 2021 were searched for the words: discharge, electrical storm, syncope, con¬vulsions. The received patients recordings were checked and all patients with electrical shocks from implantable cardioverter defibrillators (ICDs) both real and presumed were included into the study. Patients were divided into three groups: patients hospitalized due to adequate ICD discharges, patients hospitalized for other reason who had adequate interventions in the ICD memory and patients with incorrectly diagnosed ICD interventions. Results: The study group consisted of 26 patients. There was 18 men aged 65.9±10.9 and 8 women aged 68.1±12.4 (p=0.66). A total of 20 patients had electrical shocks confirmed by ICD memory checking and 6 patients had no ICD shocks. Conclusions: ED visits due to discharges of ICDs are rare. The medical history of ICD discharge could be misleading, because some patients interpret different symptoms or acoustic signals of the ICDs as a discharge. The ICD patients with syncope, unconsciousness, history of seizures should have their ICD checked for the possible discharges.