Implantable Cardioverter Defibrillator Research Articles

Mitral valve prolapse: arrhythmic risk during pregnancy and postpartum.

Arrhythmic mitral valve prolapse (AMVP) is linked to life-threatening ventricular arrhythmias (VAs), and young women are considered at high risk. Cases of AMVP in women with malignant VA during pregnancy have emerged, but the arrhythmic risk during pregnancy is unknown. The authors aimed to describe features of women with high-risk AMVP who developed malignant VA during the perinatal period and to assess if pregnancy and the postpartum period were associated with a higher risk of malignant VA. This retrospective international multi-centre case series included high-risk women with AMVP who experienced malignant VA and at least one pregnancy. Malignant VA included ventricular fibrillation, sustained ventricular tachycardia, or appropriate shock from an implantable cardioverter defibrillator. The authors compared the incidence of malignant VA in non-pregnant periods and perinatal period; the latter defined as occurring during pregnancy and within 6 months after delivery. The authors included 18 women with AMVP from 11 centres. During 7.5 (interquartile range 5.8-16.6) years of follow-up, 37 malignant VAs occurred, of which 18 were pregnancy related occurring in 13 (72%) unique patients. Pregnancy and 6 months after delivery showed increased incidence rate of malignant VA compared to the non-pregnancy period (univariate incidence rate ratio 2.66, 95% confidence interval 1.23-5.76). The perinatal period could impose increased risk of malignant VA in women with high-risk AMVP. The data may provide general guidance for pre-conception counselling and for nuanced shared decision-making between patients and clinicians.

The difficult discussion on the deactivation of implantable cardioverter devices at the end of life: a systematic review.

Implantable cardioverter defibrillators (ICDs) reliably prevent death due to life-threatening arrhythmias; this may become less relevant in people with more severe heart failure who are reaching the end of life (EOL). This review aimed to explore the ICD deactivation process and identify ethical issues, especially around the initiation of relevant discussions among professionals and patients. Available literature was reviewed using four electronic databases to identify issues that may deter healthcare professionals from having important deactivation discussions and to address considerations for ICD management prior to the EOL. The search resulted in the retainment of 12 studies. Three themes emerged from the data: barriers and facilitators, ethical considerations in clinical practice, and nurse's role. Lack of knowledge, which has been associated with cultural differences, has been found among the barriers, and interdisciplinary education and open communication appeared as facilitators. As clinicians' ethical considerations and fears emerged from the literature, nurses' special role has not been sufficiently supported. Complex care requires facilitation by multidisciplinary teams and education around the device's function regarding EOL issues. Establishing expert consensus statements on advance care planning might help define the distinct roles of each healthcare practitioner involved. Further research is needed in addressing the identified gaps.

Cardiovascular outcomes for people hospitalised with COVID-19 in Australia, and the effect of vaccination: anobservational cohort study.

To assess the frequency of clinical cardiovascular outcomes for people hospitalised with coronavirus disease 2019 (COVID-19), and the impact of vaccination. Observational cohort study. All index admissions of adults with laboratory-confirmed COVID-19 to 21 hospitals participating in the Australian Cardiovascular COVID-19 Registry (AUS-COVID), 4September 2020 - 11 July 2022. Frequency of elevated troponin levels, new arrhythmia, new or deteriorating heart failure or cardiomyopathy, new pericarditis or myocarditis, new permanent pacemaker or implantable cardioverter-defibrillator, and pulmonary embolism. impact of COVID-19 vaccination on likelihood of in-hospital death, intubation, troponin elevation, and clinical cardiovascular events. The mean age of the 1714 people admitted to hospital with COVID-19 was 60.1 years (standard deviation, 20.6 years); 926 were men (54.0%), 181 patients died during their index admissions (10.6%), 299 required intensive care (17.4%). Thirty-eight patients (2.6%) developed new atrial fibrillation or flutter, 27 (2.6%) had pulmonary embolisms, new heart failure or cardiomyopathy was identified in 13 (0.9%), and pre-existing cardiomyopathy or heart failure was exacerbated in 21 of 110 patients (19%). Troponin was elevated in 369 of the 986 patients for whom it was assessed (37.4%); in-hospital mortality was higher for people with elevated troponin levels (86, 23% v 23, 3.7%; P < 0.001). The COVID-19 vaccination status of 580 patients was known (no doses, 232; at least one dose, 348). The likelihood of in-hospital death (adjusted odds ratio [aOR], 0.38; 95% confidence interval [CI], 0.18-0.79) and intubation (aOR, 0.30; 95% CI, 0.15-0.61) were lower for people who had received at least one vaccine dose, but not the likelihood of troponin elevation (aOR, 1.44; 95% CI, 0.80-2.58) or clinical cardiovascular events (aOR, 1.56; 95% CI, 0.59-4.16). Although troponin levels were elevated in a considerable proportion of people hospitalised with COVID-19, clinical cardiovascular events were infrequent, and their likelihood was not influenced by vaccination. COVID-19 vaccination, however, was associated with reduced likelihood of in-hospital death and intubation. Australian and New Zealand Clinical Trials Registry, ACTRN12620000486921 (prospective).

Hypertrophic cardiomyopathy and competitive sports: let 'em play?

Hypertrophic cardiomyopathy (HCM) is one of the most common cardiovascular genetic conditions. Although most patients with HCM typically do well clinically, there is a small but real incidence of sudden cardiac death. A diagnosis of HCM was previously a reason for complete exclusion in sports, particularly competitive sports.However, many of these recommendations are based on expert consensus, and much data has been published in the last decade furthering the scientific knowledge in this area, and allowing athletes who may have been previously excluded the potential to participate in strenuous activities and competitive sports. With recent publications on participation in sports with HCM, as well as an emphasis on shared decision-making, more athletes with HCM are participating in competitive sports, even at a professional level. Even contact sports in the presence of an implantable cardioverter-defibrillator are no longer mutually exclusive in the current era. Previous guidelines were likely overly restrictive for patients with HCM. Although there is a risk of sudden death that cannot be ignored, the potential for shared decision making as well as medical guidance are entering a new era in all aspects of medicine, particularly in sports participation.

New York Heart Association functional class and implantable cardioverter-defibrillator in non-ischaemic heart failure with reduced ejection fraction: Extended follow-up of the DANISH trial.

Current guidelines recommend implantable cardioverter-defibrillator (ICD) therapy in patients with heart failure, a left ventricular ejection fraction of ≤35%, and New York Heart Association (NYHA) class II-III. However, the evidence regarding the benefit of primary prevention ICD is less consistent in patients with NYHA class III. We investigated the long-term effects of primary prevention ICD implantation according to NYHA class in an extended follow-up study of the DANISH trial. The DANISH trial randomized 1116 patients with non-ischaemic heart failure with reduced ejection fraction (HFrEF) to ICD implantation or usual care. Outcomes were analysed according to NYHA class at baseline (NYHA class II and III/IV). The primary outcome was all-cause mortality. Of the 1116 patients randomized in the DANISH trial, 597 (53.5%) were in NYHA class II at baseline, 505 (45.3%) in NYHA class III, and 14 (1.3%) in NYHA class IV. During a median follow-up of 9.5 years, NYHA class III/IV, compared with NYHA class II, were associated with a greater long-term rate of all-cause mortality (hazard ratio [HR] 1.52, 95% confidence interval [CI] 1.20-1.93) and cardiovascular death (HR 1.95 [1.47-2.60]). ICD implantation, compared with usual care, did not reduce the long-term rate of all-cause mortality (all participants: HR 0.89 [95% CI 0.74-1.08]; NYHA class II: HR 0.85 [0.64-1.13]; NYHA class III/IV: HR 0.89 [0.69-1.14]; pinteraction = 0.78) or cardiovascular death (all participants: HR 0.87 [95% CI 0.70-1.09]; NYHA class II: HR 0.78 [0.54-1.12]; NYHA class III/IV: HR 0.89 [0.67-1.19]; pinteraction = 0.58), irrespective of NYHA class. Similarly, NYHA class did not modify the beneficial effects of ICD implantation on sudden cardiovascular death (all participants: HR 0.60 [95% CI 0.40-0.92]; NYHA class II: HR 0.73 [0.40-1.36]; NYHA class III/IV: HR 0.52 [0.29-0.94]; pinteraction = 0.39). In patients with non-ischaemic HFrEF, ICD implantation, compared with usual care, did not reduce the overall mortality rate, but it did reduce sudden cardiovascular death, regardless of baseline NYHA class. ClinicalTrials.gov NCT00542945.

Pulmonary artery pressure monitoring in chronic heart failure: effects across clinically relevant subgroups in the MONITOR-HF trial.

In patients with chronic heart failure (HF), the MONITOR-HF trial demonstrated the efficacy of pulmonary artery (PA)-guided HF therapy over standard of care in improving quality of life and reducing HF hospitalizations and mean PA pressure. This study aimed to evaluate the consistency of these benefits in relation to clinically relevant subgroups. The effect of PA-guided HF therapy was evaluated in the MONITOR-HF trial among predefined subgroups based on age, sex, atrial fibrillation, diabetes mellitus, left ventricular ejection fraction, HF aetiology, cardiac resynchronisation therapy, and implantable cardioverter defibrillator. Outcome measures were based upon significance in the main trial and included quality of life, clinical, and PA pressure endpoints, and were assessed for each subgroup. Differential effects in relation to the subgroups were assessed with interaction terms. Both unadjusted and multiple testing adjusted interaction terms were presented. The effects of PA monitoring on quality of life, clinical events, and PA pressure were consistent in the predefined subgroups, without any clinically relevant heterogeneity within or across all endpoint categories (all adjusted interaction P-values were nonsignificant). In the unadjusted analysis of the primary endpoint quality-of-life change, weak trends towards a less pronounced effect in older patients (Pinteraction = 0.03; adjusted Pinteraction = 0.33) and diabetics (Pinteraction = 0.01; adjusted Pinteraction = 0.06) were observed. However, these interaction effects did not persist after adjusting for multiple testing. This subgroup analysis confirmed the consistent benefits of PA-guided HF therapy observed in the MONITOR-HF trial across clinically relevant subgroups, highlighting its efficacy in improving quality of life, clinical, and PA pressure endpoints in chronic HF patients.

Comparison of outcomes and required tools between transvenous extraction of pacemaker and implantable cardioverter defibrillator leads: Insight from single high-volume center experience.

Reports of comparison with procedural outcomes for implantable cardioverter defibrillator (ICD) and pacemaker (PM) transvenous lead extraction (TLE) are old and limited. We sought to compare the safety, efficacy, and procedural properties of ICD and PM TLE and assess the impact of lead age. The study cohort included all consecutive patients with ICD and PM TLE in the Cleveland Clinic Prospective TLE Registry between 2013 and 2022. Extraction success, complications, and failure employed the definitions described in the HRS 2017 TLE guidelines. A total of 885 ICD leads, a median implant duration of 8 (5-11) years in 810 patients, and 1352 PM leads of 7 (3-13) years in 807 patients were included. Procedural success rates in ICD patients were superior to those of PM in >20 years leads but similar in ≤20 years leads. In the PM group, the complete success rate of TLE decreased significantly according to the increase of lead age, but not in the ICD group. ICD TLE required more extraction tools compared with PM TLE but cases with older leads required non-laser sheath extraction tools in both groups. The most common injury site in major complication cases differed between ICD and PM TLE, although major complication rates showed no difference in both groups (2.7% vs. 1.6%, p = .12). The procedural success rate by TLE is greater for ICD patients than PM patients with leads >20 years old but requires more extraction tools. Common vascular complication sites and the impact of lead age on procedural outcomes and required tools differed between ICD and PM TLE.

De-escalating treatments and transitioning care in a cardiac intensive care units network

Abstract Funding Acknowledgements None. Background Recent data (1) have shown that end-of-life (EOL) management of patients with acute decompensated heart failure (ADHF) in Cardiac Intensive Care Units (CICU) is aggressive, with late or no involvement of palliative care (PC) teams. Purpose To evaluate current PC and EOL practices in a contemporary multicenter registry of patients with ADHF who deteriorated to cardiogenic shock (CS). Methods A survey-based approach was used to collect data on PC and EOL management practices. We enrolled CS patients from 12 participating centers. A subset of 153 patients with ADHF-CS, enrolled between March 2020 and March 2023, was analyzed. We asked participating centers to report their practice regarding de-escalating treatments and transitioning care in the context of EOL, focusing on 1) discussion of implantable cardioverter defibrillator (ICD) deactivation with patients, 2) documentation of do-not-resuscitate (DNR) orders in the patient's medical record, and 3) documentation of advance directives in the patient's medical record. We also examined early PC team involvement and ICD deactivation as indicators of de-escalating treatments and transitional care in ADHF-CS. Results are presented as numbers and percentages (%) for categorical variables and medians (interquartile range, IQR) for continuous variables. Results Baseline characteristics of the population are shown in Table 1. Figure 1 describes the practices of the participating centers. DNR was routinely documented in the medical records in only 5 of 12 centers (41.7%). PC teams were involved in 21 of 153 enrolled ADHF-CS patients (13.7%). Of the 51 patients with an ICD, 17 died: 13 patients (76%) died in the hospital and 4 (24%) died within 6 months of discharge. ICD deactivation occurred in 6 of 17 deceased patients (35.3%). One patient had ICD deactivation supported by home PC services. Conclusions This study shows that the practice of de-escalating therapy, including ICD deactivation, is not routine in the participating centers. Our findings highlight the importance of integrating PC as a concurrent process with intensive care to effectively address the unmet needs of these patients and their families.

What if youth is not enough? Acute coronary syndrome in young patients

Abstract Funding Acknowledgements None. Background Acute Coronary Syndromes (ACS) are the leading cause of mortality in Spain. Further research is needed in order to know risk factors and outcomes in young patients so that medicians could optimize their management and prevention. Purpose Identifying risk factors, clinical characteristics and short-term outcomes in Acute Coronary Syndrome in patients aged 40 and under. Methods A retrospective analysis of patients under 40 years of age who were admitted for ACS, out of 3,859 ACS admissions in Cardiology Intensive Care Unit (CICU) in our hospital between 2012 and 2022. Results 67 patients (1.73%) were included, most of them were males (83.6%). Baseline characteristics are summarized in Table 1. 77.6% had hypertension (HTA), 22.4% had diabetes (DM) and 34.3% had dyslipidemia (DLP). 79.1% were smokers, 9.1% had a history of alcoholism and 29.9% were cocaine users. None of them had a history of stroke, atrial fibrillation (AF). Only 3% had ischemic heart disease. 68.7% of them were ST-elevation myocardial infarction (STEMI) and inferior STEMI was the most common (38.7%). In anterior STEMI (22 patients), 15 had a severe lesion in the mid-left anterior descending artery (LAD), and 6 in the left main stem (LM). Single-vessel disease was the most common (70.8%), with 3-vessel disease in 4.6%. 75.8% received percutaneous coronary intervention (PCI), and 3% underwent bypass surgery. During admission, 10.5% progressed to Killip class III-IV. The ICU mortality was 1.5%. 9% received vasoactive drugs and 4.5% were intubated. Non-invasive ventilation was used in 3% and high-flow nasal cannula oxygen therapy in 5.3%. 3% received intra-aortic balloon pump support and 1.5% underwent dialysis or ultrafiltration. 4.5% received an implantable cardioverter-defibrillator (ICD), although none of them developed bundle branch block or atrioventricular node block, nor AF. After discharge, 11.1% had recurrent ACS, and up to 5.6% underwent PCI again, with a mortality rate of 11.8%. Conclusion Approximately 2% of ACS occur in people younger than 40 years of age. Substance abuse (smoking, cocaine and alcoholism) becomes more prevalent in this group. Prevalence of comorbidities (such as diabetes and nephropathy) are lower, making them less prone to short-term heart failure. However, they are more susceptible to recurrent ischemic events. There is a high incidence of inferior STEMI and LM-STEMI. For these reasons, medicians may need to find out a substance abuse in this group and further research into other risk factors, such as coronary disease family history.Basal characteristicsClinical evolution of patients

Atrioventricular block in patients with acute myocardial infarction in a state of cardiogenic shock

Abstract Funding Acknowledgements Type of funding sources: Public hospital(s). Main funding source(s): University Hospital of Virgen Macarena. Introduction Atrioventricular block (AVB) is a complication to consider in patients with acute myocardial infarction (AMI), constituting a factor in decompensation that can contribute to the shock state in some patients. Purpose The study analyzed the incidence of AVB and its relationship with the culprit artery, mortality, and the final need for device implantation. Methods A single-center, observational, retrospective study included patients admitted to the Coronary Care Unit in a state of cardiogenic shock in the context of AMI between July 2011 and September 2022. Results A total of 298 patients with AMI in a state of shock were included. The average age of the sample was 69 years, with 66.7% being male, 66.8% having hypertension, 55% having dyslipidemia, 50% having diabetes, and 33% being smokers. Nearly half of the patients (47.86%) already presented with a Killip Kimball class IV at the time of admission. The left anterior descending artery (LAD) was responsible for the infarction in 57.4% of cases, and the right coronary artery (RCA) in 24.8%. The incidence of AVB was significantly higher in patients with RCA infarctions compared to LAD (39.1% vs. 3.1%) and compared to other vessels (39.1% vs. 6.69%), with this significance remaining in any type of acute coronary syndrome. The need for device implantation was infrequent. Patients with LAD infarctions required more implantation of implantable cardioverter-defibrillators (ICDs) compared to RCA infarctions (4.43% vs. 0.49%), and RCA infarctions required more conventional pacemaker implantation (2.7% vs. 0%). A better prognosis was observed in RCA involvement with lower mortality compared to other vessels (OR 0.35, 95% CI 0.19-1.6; p=0.01) and compared to LAD involvement (OR 0.44, 95% CI 0.23-0.84; p=0.013). Conclusions The incidence of AVB was a particularly common complication in patients in a state of shock with RCA infarctions. However, the mortality was significantly lower in this subgroup of patients. Regardless of the responsible artery, the need for device implantation was infrequent, with a notable need for ICDs in LAD involvement and pacemakers in RCA involvement.

Implantable cardioverter defibrillator deactivation discussions: insights from healthcare professionals to enhance clinical practice and future research.

Implantable cardioverter defibrillator deactivation discussions: insights from healthcare professionals to enhance clinical practice and future research.

Comparative Analysis of Response to Cardiac Resynchronisation Therapy Upgrades in Patients with Implantable Cardioverter-Defibrillators and Pacemakers

Introduction: The efficacy of de novo cardiac resynchronisation therapy (CRT) in patients with heart failure (HF), left ventricular systolic dysfunction (LVSD), and a broad QRS morphology is well established. However, the optimal stage for upgrading patients with existing pacemakers (PPMs) or implantable cardioverter-defibrillators (ICDs) and HF with high-burden right ventricular (RV) pacing remains uncertain. Thus, this multicentre retrospective analysis compared patients with pre-existing PPMs or ICDs who underwent CRT upgrades to investigate the appropriate stage for CRT implantation in these patients and to assess the validity of treating both PPM and ICD recipients under the same recommendation level in the current guidelines. Materials and Methods: A total of 151 participants underwent analysis in this study, comprising 93 upgrades to cardiac resynchronisation therapy with pacemaker (CRT-P) and 58 upgrades to cardiac resynchronisation therapy with defibrillator (CRT-D) across three centres in the UK. The aim of the study was to investigate the safety and efficacy of upgrading to CRT from an existing conventional pacemaker or an ICD in the context of high-burden RV pacing. The analysis was conducted separately for each group, assessing changes in echocardiographic parameters, functional New York Heart Association (NYHA) class, and procedure-related complications. Results: The PPM group had a higher percentage RVP burden compared to the ICD group. Post-upgrade, NYHA functional class and EF and LV volumes improved in both groups; however, the response to an upgrade from a pacemaker was greater compared to an upgrade from an ICD. Post-procedural complication risks were similar across the two subgroups but significantly higher compared to de novo implantation. Conclusions: Within the CRT-P subgroup, participants exhibited better responses than their CRT-D counterparts, evident both in echocardiographic improvements and clinical outcomes. Furthermore, patients with non-ischemic cardiomyopathy (NICM) were better responders than those with ischaemic cardiomyopathy. These findings suggest that international guidelines should consider approaching each subgroup separately in the future.

Morbidity and mortality outcomes of patients requiring isolated tricuspid valve surgery: a retrospective cohort study of 537 patients in New South Wales between 2002 and 2018

ObjectivesThe aim of the study was to evaluate mortality and morbidity outcomes following open-heart isolated tricuspid valve surgery (TVSx) with medium to long-term follow-up.DesignRetrospective cohort study.SettingNew South Wales public and...

Balloon venoplasty for right heart catheterization from the arm in patients with subclavian vein stenosis.

In the trans-radial era, arm venous access for right heart catheterization (RHC) is rising. Procedural success is affected by many factors, including subclavian/innominate vein stenosis (SVS) and pre-existing wires or catheters. In a study published previously by the same authors, 2% of cases had unsuccessful RHC through the arm, predominantly due to SVS. Since that study, techniques to improve RHC success rates have been developed, including crossing the stenosis with a coronary guidewire, followed by balloon dilatation. We aimed to determine whether subclavian/innominate venoplasty allows successful RHC in patients with SVS. Our retrospective study included patients who had RHC from the arm between November 1, 2019, and December 31, 2022 that was unsuccessful due to the inability to pass a catheter through the SVS, and then underwent balloon venoplasty. The success rate of completed RHC was then assessed. Out of 2506 RHCs via arm access, 2488 were successful with a catheter alone or over a guidewire. In 18 patients, venoplasty was needed for catheter passage over a guidewire. Post-dilatation, all 18 cases (100%) had successful RHC with a mean procedural time of 35.2 (SD = 15.5) minutes. The most common stenosis site was the subclavian vein in 13 patients (72.2%), and 12 patients (66.7%) had pacemaker/ implantable cardioverter defibrillator wires present. Balloon dilatation of SVS is an efficacious method to improve the success rate of RHC from the arm. It is a safe technique that may prevent cross-over to a different access site, thereby improving patient satisfaction and reducing the possibility of alternate site complications.

Competing Risks for Monomorphic versus Non-Monomorphic Ventricular Arrhythmias in Primary Prevention Implantable Cardioverter Defibrillator Recipients: Global Electrical Heterogeneity and Clinical Outcomes (GEHCO) Study.

Ablation of monomorphic ventricular tachycardia (MMVT) has been shown to reduce shock frequency and improve survival. We aimed to compare cause-specific risk factors of MMVT and polymorphic ventricular tachycardia (PVT)/ventricular fibrillation (VF) and to develop predictive models. The multicenter retrospective cohort study included 2,668 patients (age 63.1±13.0 y; 23% female; 78% white; 43% nonischemic cardiomyopathy, left ventricular ejection fraction 28.2±11.1%). Cox models were adjusted for demographic characteristics, heart failure severity and treatment, device programming, and ECG metrics. Global electrical heterogeneity was measured by spatial QRS-T angle (QRSTa), spatial ventricular gradient elevation (SVGel), azimuth, magnitude (SVGmag), and sum absolute QRST integral (SAIQRST). We compared the out-of-sample performance of the lasso and elastic net for Cox proportional hazards and the Fine-Gray competing risk model. During a median follow-up of 4 years, 359 patients experienced their first sustained MMVT with appropriate ICD therapy, and 129 patients had their first PVT/VF with appropriate ICD shock. The risk of MMVT was associated with wider QRSTa (HR 1.16; 95%CI 1.01-1.34), larger SVGel (HR 1.17; 95%CI 1.05-1.30), and smaller SVGmag (HR 0.74; 95%CI 0.63-0.86) and SAIQRST (HR 0.84; 95%CI 0.71-0.99). The best-performing 3-year competing risk Fine-Gray model for MMVT (ROC(t)AUC 0.728; 95%CI 0.668-0.788) identified high-risk (> 50%) patients with 75% sensitivity, 65% specificity, and PVT/VF prediction model had ROC(t)AUC 0.915 (95%CI 0.868-0.962), both satisfactory calibration. We developed and validated models to predict the competing risks of MMVT or PVT/VF that could inform procedural planning and future RCTs of prophylactic VT ablation.

Electrically Conductive Collagen-PEDOT:PSS Hydrogel Prevents Post-Infarct Cardiac Arrhythmia and Supports hiPSC-Cardiomyocyte Function.

Myocardial infarction (MI) causes cell death, disrupts electrical activity, triggers arrhythmia, and results in heart failure, whereby 50-60% of MI-associated deaths manifest as sudden cardiac deaths (SCD). The most effective therapy for SCD prevention is implantable cardioverter defibrillators (ICDs). However, ICDs contribute to adverse remodeling and disease progression and do not prevent arrhythmia. This work develops an injectable collagen-PEDOT:PSS (poly(3,4-ethylenedioxythiophene) polystyrene sulfonate) hydrogel that protects infarcted hearts against ventricular tachycardia (VT) and can be combined with human induced pluripotent stem cell (hiPSC)-cardiomyocytes to promote partial cardiac remuscularization. PEDOT:PSS improves collagen gel formation, micromorphology, and conductivity. hiPSC-cardiomyocytes in collagen-PEDOT:PSS hydrogels exhibit near-adult sarcomeric length, improved contractility, enhanced calcium handling, and conduction velocity. RNA-sequencing data indicate enhanced maturation and improved cell-matrix interactions. Injecting collagen-PEDOT:PSS hydrogels in infarcted mouse hearts decreases VT to the levels of healthy hearts. Collectively, collagen-PEDOT:PSS hydrogels offer a versatile platform for treating cardiac injuries.

Long-term follow-up of patients with Brugada syndrome: Foremost risk factors associated with overall arrhythmic events.

Brugada syndrome (BS) is characterized by ST segment elevation in right precordial leads (V1-V3), ventricular tachycardia (VT), ventricular fibrillation (VF), and sudden cardiac death (SCD) in individuals without structural heart disease. The aim of this study is to contribute to the controversial issue of finding the most valuable marker that can predict poor prognosis during follow-up in patients with a diagnosis of BS. A total of 68 patients diagnosed with BS or had Brugada-type ECG change between January 1997 and July 2012 at the Department of Cardiology of Başkent University Faculty of Medicine, Ankara, Turkey, were included in this cohort study. Patients were screened every 6 months for arrhythmia-related syncope, SCD, appropriate and inappropriate defibrillation (shock), AF development and death; collectively defined as "arrhythmic events" and were the primary endpoints. Patients with and without arrhythmic events were compared. The mean age was 34.9 ± 12.2 years (9-71 years), and 52 (76.5%) patients were male. Mean follow-up was 49.6 ± 37.6 months (4-188 months). Univariate analysis showed that male sex (P = .004), type 1 electrocardiographic pattern (P = .008), SCD (P = .036), VT/VF history (P = .046), requirement for electrophysiological studies (P = .034), implantable cardioverter-defibrillator placement (P = .014) were found to demonstrate significant differences in patients with and without arrhythmic events. In multivariable analyzes, spontaneous type 1 ECG presence (HR = 8.54, 95% CI: 0.38-26.37; P = .003) and VT/VF history (HR = 9.21, 95% CI: 0.004-1.88; P = .002) were found to be independently associated with arrhythmic events. We found the presence of spontaneous type 1 ECG and a history of VT/VF to be associated with increased likelihood of overall arrhythmic events in BS. Given the higher risk of poor prognosis, we recommend additional measures in patients with BS who have these features.

Sex differences among subcutaneous defibrillator (S-ICD) recipients: a propensity-matched, multicenter, international analysis from the i-SUSI project.

Women have been historically underrepresented in implantable cardioverter defibrillator (ICD) trials. No data on sex differences regarding subcutaneous-ICDs (S-ICD) carriers have been described. Aim of our study was to investigate sex-related differences among unselected S-ICD recipients. Consecutive patients enrolled in the multicenter, international i-SUSI registry were analyzed. Comparisons between sexes were performed using a 1:1 propensity matching adjusted analysis for age, body mass index (BMI), left ventricular function and substrate. The primary outcome was the rate of appropriate shocks during follow-up. Inappropriate shocks and other device-related complications were deemed secondary outcomes. A total of 1698 patients were extracted from the iSUSI registry; 399 (23.5%) were females. After propensity matching, two cohorts of 374 patients presenting similar baseline characteristics were analyzed. Despite similar periprocedural characteristics and a matched BMI, women resulted at lower risk of conversion failure as per PRAETORIAN score (73.4% vs 81.3%, p = 0.049). Over a median follow-up time of 26.5 [12.7-42.5] months, appropriate shocks were more common in the male cohort (rate/year 3.4%vs1.7%; log-rank p = 0.049), while no significant differences in device-related complications (rate/year: 6.3% vs 5.8%; log-rank p = 0.595) and inappropriate shocks (rate/year: 4.3%vs3.1%; log-rank p = 0.375) were observed. After controlling for confounders, sex remained significantly associated with the primary outcome (aHR 1.648; CI 0.999-2.655, p = 0.048), while not resulting predictor of inappropriate shocks and device-related complications. In a propensity-matched cohort of S-ICD recipients, women are less likely to experience appropriate ICD therapy, while not showing higher risk of device related-complications.

Automatic implantable cardioverter defibrillator (AICD) implantation as secondary prevention of cardiac sarcoidosis-associated ventricular tachycardia

  Background: Cardiac sarcoidosis can cause a wide range of symptoms, including shortness of breath, chest pain, oedema, and fatal arrhythmias such as ventricular tachycardia (VT). Because the symptoms can be nonspecific, diagnosing cardiac sarcoidosis can be challenging. Treatment options may include corticosteroids to reduce inflammation, immunosuppressive drugs to prevent further damage, medications to control symptoms, ablation procedures, and defibrillators to prevent cardiac arrest. Case: A 60-year-old woman who has sarcoidosis affecting multiple organs including cardiac sarcoidosis, non-ischemic cardiomyopathy with reduced ejection fraction, and hypertension, was admitted with tachycardia, shortness of breath, and a recently fired automatic implantable cardioverter defibrillator (AICD). Three months prior, the patient was admitted for a syncopal episode and diagnosed with cardiac sarcoidosis through cardiac magnetic resonance imaging (MRI) and positron emission tomography (PET), which demonstrated active inflammation, and an AICD was implanted. During this admission, the patient had an episode of ventricular tachycardia and was treated with amiodarone and lidocaine. The patient received steroids, sacubitril/valsartan, and methotrexate. After 48 hours of observation, the patient was discharged without further events. Conclusion: Cardiac sarcoidosis is a rare but serious disease that can lead to life-threatening cardiac complications such as ventricular tachycardia. Early diagnosis and aggressive management are crucial for improving outcomes and preventing sudden cardiac death. AICD implantation as a secondary prevention in cardiac sarcoidosis might prevent cardiac arrest.

Active Arrhythmia Pattern: A Novel Predictor of ICD Shocks-A Subanalysis From the PARTITA Study.

In the PARTITA trial (Does Timing of Ventricular Tachycardia Ablation Affect Prognosis in Patients With an Implantable Cardioverter Defibrillator?), antitachycardia pacing (ATP) predicted the occurrence of implantable cardioverter defibrillator (ICD) shocks. Catheter ablation of ventricular tachycardia after the first shock reduced the risk of death or worsening heart failure. A threshold of ATPs that might warrant an ablation procedure before ICD shocks is unknown. Our aim was to identify a threshold of ATPs and clinical features that predict the occurrence of shocks and cardiovascular events. We analyzed data from 517 patients in phase A of the PARTITA study. We used classification and regression tree analysis to develop and test a risk stratification model based on arrhythmia patterns and clinical data to predict ICD shocks. Secondary end points were worsening heart failure and cardiovascular hospitalization. Classification and regression tree classified patients into 6 leaves by increasing shock probability. Patients treated with ≥5 ATPs in 6 months (active arrhythmia pattern) had the highest risk of ICD shocks (93% and 86%, training and testing samples, respectively). Patients without ATPs had the lowest (1% and 2%). Other predictors included left ventricle ejection fraction<35%, age of <60 years, and obesity. Survival analysis revealed a higher risk of worsening heart failure (hazard ratio, 5.45 [95% CI, 1.62-18.4]; P=0.006) and cardiovascular hospitalization (hazard ratio, 7.29 [95% CI, 3.66-14.5]; P<0.001) for patients with an active arrhythmia pattern compared with those without ATPs. Patients with an active arrhythmia pattern (≥5 ATPs in 6 months) are associated with an increased risk of ICD shocks, as well as heart failure hospitalization and cardiovascular hospitalization. These data suggest that additional treatments may be helpful to this high-risk group as a preventive strategy to reduce the incidence of major events. Further prospective randomized trials are needed to confirm the benefits of early ventricular tachycardia ablation in this setting.