Prognostic value of ventricular arrhythmia in early post-infarction left ventricular dysfunction: the French nationwide WICD-MI study.

BACKGROUND AND AIMS: Prophylactic implantable cardioverter-defibrillators (ICDs) are not recommended until left ventricular ejection fraction (LVEF) has been reassessed 40 to 90 days after an acute myocardial infarction. In the current therapeutic era, the prognosis of sustained ventricular arrhythmias (VAs) occurring during this early post-infarction phase (i.e. within 3 months of hospital discharge) has not yet been specifically evaluated in post-myocardial infarction patients with impaired LVEF. Such was the aim of this retrospective study. METHODS: Data analysis was based on a nationwide registry of 1032 consecutive patients with LVEF ≤ 35% after acute myocardial infarction who were implanted with an ICD after being prescribed a wearable cardioverter-defibrillator (WCD) for a period of 3 months upon discharge from hospital after the index infarction. RESULTS: ICDs were implanted either because a sustained VA occurred while on WCD (VA+/WCD, n = 72) or because LVEF remained ≤35% at the end of the early post-infarction phase (VA-/WCD, n = 960). The median follow-up was 30.9 months. Sustained VAs occurred within 1 year after ICD implantation in 22.2% and 3.5% of VA+/WCD and VA-/WCD patients, respectively (P < .0001). The adjusted multivariable analysis showed that sustained VAs while on WCD independently predicted recurrence of sustained VAs at 1 year (adjusted hazard ratio [HR] 6.91; 95% confidence interval [CI] 3.73-12.81; P < .0001) and at the end of follow-up (adjusted HR 3.86; 95% CI 2.37-6.30; P < .0001) as well as 1-year mortality (adjusted HR 2.86; 95% CI 1.28-6.39; P = .012). CONCLUSIONS: In patients with LVEF ≤ 35%, sustained VA during the early post-infarction phase is predictive of recurrent sustained VAs and 1-year mortality.

Efficacy of early use of Percutaneous Stellate Ganglion Block for electrical storms.

BACKGROUND: Electrical Storm (ES) is a life-threatening condition requiring a rapid management. Percutaneous Stellate Ganglion Block (PSGB) proved to be safe and effective on top of standard therapy, but no data are available about its early use. METHODS: We considered all patients enrolled from 1st July 2017 to 30th April 2024 in the STAR registry (STellate ganglion block for Arrhythmic stoRm), a multicentre, international, observational, prospective registry. We aimed to assess the effectiveness of the first PSGB only. Patients were divided into two groups depending on whether they received PSGB before (Early-PSGB, often due to AAD contraindication) or after (Delayed-PSGB) intravenous antiarrhythmic drugs (AADs other than beta-blockers). RESULTS: We considered 180 PSGB (26 Early-PSGB and 154 AAD-first). In the early-PSGB group we observed a statistically significant reduction of treated arrhythmic events in the hour after PSGB compared to the hour before: 0 (0-0) vs 4.5 (1-10), p<0.001 and the extent of the reduction was similar in the Early-PSGB and delayed-PSGB group [-4.5 (-7 to -2) vs. -2.5 (-3.5 to -1.5), p=ns]. The percentage of patients free from arrhythmias was similar in the two groups up to 12 hours after PSGB (81%vs 84%, p=0.6 after one hour; 77% vs 79%, p=0.8 at three hours and 65% vs 69%, p= 0.7 after 12 hours). CONCLUSIONS: PSGB proved to be effective also when used early in the treatment of ES. Due to its rapidity of action, our results may suggest its early use to reduce the number of defibrillations and possibly to reduce the likelihood of a refractory ES.

Modeling Idiopathic Ventricular Fibrillation Using iPSC Cardiomyocytes and Computational Approaches: A Proof-of-Concept Study.

Idiopathic ventricular fibrillation (IVF) is an unrefined diagnosis representing a heterogeneous patient group without a structural or genetic definition. IVF treatment is not mechanistic-based due to the lack of experimental patient-models. We sought to create a methodology to assess cellular arrhythmia mechanisms for IVF as a proof-of-concept study. Using IVF patient-specific induced pluripotent stem cell-derived cardiomyocytes, we integrate electrophysiological optical mapping with computational modeling to characterize the cellular phenotype. This approach flips the traditional paradigm using a biophysically detailed computational model to solve the problem inversely. Insight into the cellular mechanisms of this patient's IVF phenotype could also serve as a therapeutic testbed.

Evaluating cardiac risks of TASER: An in-depth case study through probable current analysis.

This study investigates the cardiac safety concerns related to TASER discharges centering on a pivotal case that marked the first TASER-related fatality in South Korea. Employing Pratt et al.'s theoretical framework, the research evaluates the potential for ventricular fibrillation (VF) from these discharges. The methodology incorporated a high-resolution waveform analysis using sophisticated equipment and considered specific incident details, including dart impact locations verified through a forensic examination. A human body impedance of 500 Ω, chosen based on empirical studies and coupled with non-inductive resistance for high-voltage handling, was utilized in the model. By applying a heart-current factor from IEC 60479 standards, the study found a VF risk of up to 5% depending on the impact location and current pathways. In this specific case, although the calculated risk did not exceed critical thresholds, the VF risk was high enough to suggest that TASER discharges played a role in the fatal outcome. This study underscores the importance of dart impact location in TASER safety evaluations, contributing to a broader understanding of TASER cardiac risks and providing a basis to advocate for rigorous safety protocols.

Factors associated with stellate ganglion block success in recurrent ventricular arrhythmias.

AIMS: One treatment option for refractory ventricular arrythmias is stellate ganglion block (SGB). We examined differences in SGB success by patient and arrhythmia characteristics and predictors of successful SGB. METHODS AND RESULTS: This was a multicenter analysis of patients treated for refractory ventricular arrythmias in the Czech Republic and the United States. The primary outcome was absence of ventricular arrythmias at 24 h post SGB. SGB effectiveness was examined according to aetiology of cardiomyopathy, arrhythmia type, laterality of SGB, presence of inotropes, and presence of mechanical circulatory support. Binary logistic regression was used to examine variables associated with the primary outcome. In total there were 117 patients with refractory ventricular arrythmias treated with SGB. Overall, the mean age was 63.5 ± 11.0 years, majority of patients were male (94.0%), White (87.2%), and had an implantable cardioverter defibrillator in situ (70.1%). There were no differences in efficacy of SGB based on aetiology of cardiomyopathy (P = 0.623), arrhythmia type (0.852), laterality of block (P = 0.131), and presence of inotropes (P = 0.083). Multivariable analysis demonstrated that increased age was associated with decreased odds of SGB success (odds ratio: 0.96, confidence interval: 0.92-0.99, P = 0.039) whereas increased left ventricular ejection fraction trended towards increased odds of SGB success (odds ratio: 1.05, confidence interval: 0.995-1.11, P = 0.077). CONCLUSIONS: In this multicentre experience, SGB was similarly effective despite the aetiology of cardiomyopathy, type of arrhythmia, laterality, and inotropic or mechanical support. SGB was less effective for the suppression of ventricular arrythmias at 24 h for the elderly.

Validation of Novel Risk Prediction Models in Patients with Brugada Syndrome: A Multicenter Study in Japan.

BACKGROUND: Risk stratification in patients with Brugada syndrome (BrS) is challenging, especially in those at intermediate risk. The Predicting Arrhythmic evenT (PAT) score has recently been demonstrated to be excellent for predicting future arrhythmic events in patients without prior ventricular fibrillation (VF). However, validation studies are lacking. OBJECTIVE: This study aimed to assess the performance of a novel risk stratification model in predicting future VF events in patients with BrS in a Japanese multicenter cohort. METHODS: The PAT score was calculated for 413 patients with BrS (mean age, 50.9±13.6 years; 395 men) from 59 hospitals in Japan, including 314 patients without prior VF. The incidence of developing VF during the follow-up period was investigated. RESULTS: During the 106.8-month follow-up period, 54 patients (13.1%) experienced VF events. Of the 314 patients without prior VF at enrollment, 14 (4.5%) experienced VF events. The incidence of VF events during the follow-up period was significantly higher in patients with PAT scores ≥10 than in those with scores <10 (41/173 [23.7%] vs. 13/240 [5.4%], p<0.0001) in the total cohort. No difference was observed in the incidence of VF events between patients with PAT scores ≥10 and <10 among the 314 patients without prior VF (6/86 [7.0%] vs. 8/228 [3.5%], p=0.22). PAT scores ≥10 predicted future VF events with a sensitivity and specificity of 42.9% and 73.3%, respectively. CONCLUSION: This Japanese multicenter registry demonstrated that the novel risk stratification model could not accurately predict future VF events in patients with BrS, but without prior VF.

Implantable Cardioverter-Defibrillators Among Older Survivors of Out-of-Hospital Cardiac Arrest.

BACKGROUND: Although current guidelines recommend implantable cardioverter-defibrillator (ICD) placement in survivors of out-of-hospital cardiac arrest, contemporary data on secondary-prevention ICDs in survivors of out-of-hospital cardiac arrest remain limited. METHODS AND RESULTS: Using 2013 to 2019 CARES (Cardiac Arrest Registry to Enhance Survival) linked to Medicare, we identified 3226 patients aged ≥65 years with an initial shockable rhythm who survived to discharge without severe neurological disability. Multivariable hierarchical regression models were used to examine the association between patient variables and ICD placement and quantify hospital variation in ICD implantation. The mean age was 72.2 years, 23.5% were women, 10% were Black individuals, and 4% were Hispanic individuals. Overall, 997 (30.9%) patients received an ICD before discharge, 1266 (39.2%) at 90 days, and 1287 (39.9%) within 6 months. Older age (≥85 years), female sex, history of diabetes, calendar year, and presentation with acute myocardial infarction were associated with lower odds of ICD implantation, but race or ethnicity was not associated with ICD implantation. Among 297 hospitals, the median proportion of survivors receiving ICD at discharge was 28.6% (interquartile range, 20%-50%). The relative odds of ICD implantation varied by 62% across hospitals (median odds ratio, 1.62 [95% CI, 1.38-1.82]) after adjusting for case mix. CONCLUSIONS: Fewer than 1 in 3 survivors of out-of-hospital cardiac arrest due to a shockable rhythm received a secondary-prevention ICD before discharge. Although patient variables were associated with ICD implantation, there was no difference by race or ethnicity. Even after adjusting for patient case mix, ICD implantation varied markedly across hospitals.

Idiopathic Ventricular Fibrillation - Just How Much Idiopathic is it?

Idiopathic ventricular fibrillation is diagnosed in survivors of sudden cardiac death that has been caused by ventricular fibrillation without known structural or electrical abnormalities, even after extensive investigation. It is a common cause of sudden death in young adults. Although idiopathic ventricular fibrillation is a diagnosis of exclusion, in many cases only a partial investigation algorithm is performed. The aim of this review is to present a comprehensive diagnostic evaluation algorithm with a focus on diagnostic assessment of inherited arrhythmic syndromes and genetic background.

Neuroprotection with hypothermic reperfusion and extracorporeal cardiopulmonary resuscitation - A randomized controlled animal trial of prolonged ventricular fibrillation cardiac arrest in rats.

Extracorporeal cardiopulmonary resuscitation (ECPR) facilitates resuscitation with immediate and precise temperature control. This study aimed to determine the optimal reperfusion temperature to minimize neurological damage after ventricular fibrillation cardiac arrest (VFCA). Twenty-four rats were randomized (n = 8 per group) to normothermia (NT = 37°C), mild hypothermia (MH = 33°C) or moderate hypothermia (MOD = 27°C). The rats were subjected to 10 minutes of VFCA, before 15 minutes of ECPR at their respective target temperature. After ECPR weaning, rats in the MOD group were rapidly rewarmed to 33°C, and temperature maintained at 33°C (MH/MOD) or 37°C (NT) for 12 hours before slow rewarming to normothermia (MH/MOD). The primary outcome was 30-day survival with overall performance category (OPC) 1 or 2 (1 = normal, 2 = slight disability, 3 = severe disability, 4 = comatose, 5 = dead). Secondary outcomes included awakening rate (OPC ≤ 3) and neurological deficit score (NDS, from 0 = normal to 100 = brain dead). The survival rate did not differ between reperfusion temperatures (NT = 25%, MH = 63%, MOD = 38%, p = 0.301). MH had the lowest NDS (NT = 4[IQR 3-4], MH = 2[1-2], MOD = 5[3-5], p = 0.044) and highest awakening rate (NT = 25%, MH = 88%, MOD = 75%, p = 0.024). In conclusion, ECPR with 33°C reperfusion did not statistically significantly improve survival after VFCA when compared with 37°C or 27°C reperfusion but was neuroprotective as measured by awakening rate and neurological function.

Circulating Autoantibodies Targeting TREK-1 in Patients With Short-Coupled Ventricular Fibrillation.

BACKGROUND: Short-coupled ventricular fibrillation (SCVF) is increasingly being recognized as a distinct primary electrical disorder and cause of otherwise unexplained cardiac arrest. However, the pathophysiology of SCVF remains largely elusive. Despite extensive genetic screening, there is no convincing evidence of a robust monogenic disease gene, thus raising the speculations for alternative pathogeneses. The role of autoimmune mechanisms in SCVF has not been investigated so far. The objective of this study was to screen for circulating autoantibodies in patients with SCVF and assess their role in arrhythmogenesis. METHODS: This is a prospective, single-center, case-control study enrolling cardiac arrest survivors diagnosed with SCVF or idiopathic ventricular fibrillation (IVF) between 2019 and 2023 at the Institut Universitaire de Cardiologie et de Pneumologie de Québec, Université Laval Inherited Arrhythmia Clinic in Canada. Plasma samples were screened for autoantibodies targeting cardiac ion channels using peptide microarray technology. Identified target autoantibodies were then purified from pooled plasma samples for subsequent cellular electrophysiological studies. RESULTS: Fourteen patients with SCVF (n=4 [29%] female patients; median age, 45 years [36, 58]; n=14 [100%] non-Hispanic White) and 19 patients with idiopathic ventricular fibrillation (n=8 [42%] female patients; median age, 49 years [38, 57]; n=19 [100%] non-Hispanic White) were enrolled in the study and compared with 38 (n=20 [53%] female subjects; median age, 45 years [29, 66]; n=36 [95%] non-Hispanic White) sex-, age- and ethnicity-matched healthy controls. During the study period, 11 (79%) SCVF probands experienced ventricular fibrillation recurrence after a median of 4.3 months (interquartile range, 0.3-20.7). Autoantibodies targeting cardiac TREK-1 (TWIK [tandem of pore-domains in a weakly inward rectifying potassium channel]-related potassium channel 1 were identified in 7 (50%) patients with SCVF (P=0.049). Patch clamp experiments demonstrated channel-activating properties of anti-TREK-1 autoantibodies that are antagonized by quinidine in both HEK293 cells and human induced pluripotent stem cell-derived cardiomyocytes. CONCLUSIONS: Patients with SCVF harbor circulating autoantibodies against the cardiac TREK-1 channel. Anti-TREK-1 autoantibodies not only present the first reported biomarker for SCVF, but our functional studies also suggest a direct implication in the arrhythmogenesis of SCVF.

Failure to treat ventricular tachycardia or ventricular fibrillation by implantable cardioverter-defibrillators.

BACKGROUND: Normally functioning implantable cardioverter-defibrillators (ICDs) with intact lead systems occasionally fail to deliver therapy for ventricular tachycardia/fibrillation (VT/VF) or deliver it only after clinically significant delays (failure-to-treat). OBJECTIVE: We aimed to investigate ICD failure-to-treat VT/VF in a large patient cohort. METHODS: We searched the US Food and Drug Administration's online Manufacturer and User Facility Device Experience (MAUDE) database from 2019 to 2023 for manufacturer-verified reports in which normally functioning ICDs failed to treat VT/VF. RESULTS: We identified 854 reports classified as deaths (n = 96 [11.2%]), injuries (n = 585 [68.5%]), or malfunctions (n = 173 [20.3%]) for normally functioning ICDs. The most common causes were misclassification as supraventricular tachycardia (SVT) or atrial fibrillation (AF; 54.8%), undersensing (21.1%), and failure to satisfy programmed rate/duration criteria (8.7%). Most events caused by misclassification as SVT/AF (89.5%) and failure to satisfy rate/duration criteria (70.3%) were VT; most caused by undersensing were either VF (54.4%) or not specified as VT or VF (19.4%). Undersensing caused 65.6% of deaths, although it represented only 21.1% of reports. In the United States, the number of reports increased faster than that of ICD patients. CONCLUSION: In the largest reported series of failure-to-treat VT/VF by normally functioning ICDs, the most common cause was misclassification of VT as SVT/AF; the most common cause of death was undersensing of VF. Although relatively few patients with normally functioning ICDs experience failure-to-treat VT/VF, the absolute number of verified MAUDE reports suggests that more work is needed to quantify the magnitude of the problem, to identify root causes, and to develop solutions.

Successful treatment of sepsis-induced cardiomyopathy with 36 hours refractory ventricular fibrillation: A case report.

Sepsis-induced cardiomyopathy (SIC) is generally characterized by decreased cardiac ejection fraction (EF) reversibility, less cardiac response to fluid resuscitation and catecholamine, and rarely complicated with refractory ventricular fibrillation (RVF). Once RVF is induced, the mortality rate of sepsis patients will be greatly increased. In this case, we reported a 26-year-old female patient who was diagnosed sepsis-induced cardiomyopathy (SIC), presented with RVF for 36 hours. The patient was maintained by the mechanical circulatory support (MCS) devices and experienced twice defibrillation. Finally, the patient was discharged without intracardial thrombosis and severe craniocerebral complications. This case suggested that early application of MCS and appropriate frequency of defibrillation may help the prognosis of SIC with RVF.

Clinical performance of AED shock advisory system with integrated Analyze Whilst Compressing algorithm for analysis of the ECG rhythm during out-of-hospital cardiopulmonary resuscitation: A secondary analysis of the DEFI 2022 study.

Objective: This study involving automated external defibrillators (AEDs) in early treatment of refibrillation aims to evaluate the performance of a new shock advisory system (SAS) during chest compressions (CC) in out-of-hospital cardiac arrest (OHCA) patients. Methods: This work focuses on AED SAS performance as a secondary outcome of DEFI 2022 clinical prospective study, which included first-analysis shockable OHCA patients. SAS employs the Analyze Whilst Compressing (AWC) algorithm to interact with both cardiopulmonary resuscitation (CPR) and shock advice by conditional operation of two-stage ECG analysis in presence or absence of chest compressions. AWC is triggered by the first-shock recommendation. Then, after 1 min of CPR, ECG analysis during CC decides between two treatment scenarios. For patients with refibrillation, CPR is paused for immediate confirmation analysis and shock advice. For patients with non-shockable rhythms, CPR is continued for 2 min until standard analysis. Results: Clinical data from 285 OHCA patients with shock recommendation at the first-analysis by AEDs (DEFIGARD TOUCH7, Schiller Médical) consisted of 576 standard analyses, 2011 analyses during CC, 577 confirmation analyses in absence of CC. Global AED SAS performance meets the standard recommendations for arrhythmia analysis sensitivity (94.9%) and specificity (>99.3%). AWC provided innovative treatment of shockable rhythms by stopping CPR earlier than 2 min in most ventricular fibrillations (92.9%), while most non-shockable patients (86.5-95.2%) benefitted from continuous CPR for at least 2 min. Conclusion: This study provides positive evidence for routine use of AEDs with AWC-integrated algorithm for ECG analysis during CPR by first-responders in early OHCA treatment.Clinical Trial Registration: Registration number: NCT04691089, trial register: ClinicalTrials.gov.

Substrate Characterization and Outcomes of Ventricular Tachycardia Ablation in Amyloid Cardiomyopathy: A Multicenter Study.

BACKGROUND: Sustained ventricular tachycardia (VT) in cardiac amyloidosis is uncommon, and the substrate and outcomes of catheter ablation are not defined. METHODS: We included 22 consecutive patients (mean age, 68±10 years; male sex, 91%) with cardiac amyloidosis (ATTR [transthyretin], n=16; light chain, n=6) undergoing catheter ablation for VT/ventricular fibrillation (VF) between 2013 and 2023 in a retrospective, observational, international study. The primary efficacy outcome was recurrent VT/VF during follow-up, while the primary safety end point included major procedure-related adverse events. RESULTS: The indication for ablation was drug-refractory VT in 17 patients (77%), and premature ventricular complex-initiated polymorphic VT/VF in 5 patients (23%). Catheter ablation was performed using endocardial (n=17.77%) or endo-epicardial approaches (n=5.23%). Complete endocardial electroanatomical voltage maps of the left and right ventricles were obtained in 17 (77%) and 10 (45%) patients, respectively. Each patient had evidence of low-voltage areas, most commonly involving the interventricular septum (n=16); late potentials were recorded in 16 patients (73%). A median of 1 (1-2) VT was inducible per patient; 12 of the 26 mappable VTs (46%) originated from the interventricular septum. Complete procedural success was achieved in 16 patients (73%), with 4 (18%) major procedure-related adverse events. After a median follow-up of 32 (14-42) months, sustained VT/VF recurrence was observed in 9 patients (41%); survival free from VT/VF recurrence was 56% (95% CI, 36%-86%) at 36-month follow-up, and most patients remained on antiarrhythmic drugs. A significant reduction in per patient implantable cardioverter defibrillator therapies was noted in the 6-month period after ablation (before: 6 [4-9] versus after: 0 [0-0]; P<0.001). In multivariable analysis, complete procedural success was associated with reduced risk of recurrent VT/VF (hazard ratio, 0.002; P=0.034). CONCLUSIONS: Catheter ablation can achieve control of recurrent VT/VF in more than half of patients with cardiac amyloidosis, and the reduction in VT/VF burden post-ablation may be relevant for quality of life. Septal substrate and risk of procedure-related complications challenge successful management of patients with cardiac amyloidosis and VT/VF.

Late gadolinium enhancement in early repolarization syndrome.

BACKGROUND: In patients with Brugada syndrome, myocardial fibrosis can be identified through epicardial biopsy or cardiac magnetic resonance (CMR) imaging with late gadolinium enhancement (LGE). However, the myocardial alterations in patients with early repolarization syndrome (ERS) remain poorly elucidated. OBJECTIVE: The objective of this study was to investigate the presence of myocardial fibrosis in patients with ERS by LGE in CMR. METHODS: We retrospectively evaluated 20 patients with ERS, all of whom exhibited J waves in the contiguous 2 leads. The location of J waves was classified as in the septum (V1-V2), anterior (V3-V4), lateral (I, aVL, V5-V6), inferior (II, III, aVF), or posterior (V7-V9) regions. To compare the distribution of LGE on CMR imaging with J waves, sections on short-axis view of the left ventricle (LV) were categorized as located in the septum, anterior, lateral, inferior, and posterior regions. RESULTS: Overall, 85% of ERS patients displayed LGE, which was more prevalent in the septum and posterior regions, followed by the inferior and lateral regions. The presence or absence of J waves and LGE coincided in 61% of LV areas, whereas discordance between the distributions of J waves and LGE was observed in 38%. LGE was most frequent in the septum (75%), where its reflection in J waves may be less robust. The appearance of LGE was not associated with symptoms, electrical storm, or ventricular fibrillation occurrence during follow-up. CONCLUSION: LGE is common in patients with ERS, and the distribution of J waves and LGE coincides in approximately 60% of LV areas.

Challenges and strategies regarding anaesthetic management of twin pregnancy undergoing redo aortic valve replacement.

INTRODUCTION AND IMPORTANCE: Redo aortic valve replacement in twin pregnancy presents significant challenges because of the elevated risks for both maternal and fetal health. Mortality rates range from 12 % to 21 % in specialised centres, with previous cardiac surgeries further elevating the risk. Pregnancy complicates cardiac surgery, with fetal mortality rates as high as 16-33 %. PRESENTATION OF CASE: A 31-year-old woman, 15 weeks pregnant with twins and with a history of mechanical aortic valve replacement, presented with worsening breathlessness and grade III dyspnoea. Echocardiography revealed severe valve obstruction, necessitating redo-aortic valve replacement and posterior aortic root enlargement. Despite intraoperative challenges, including ventricular fibrillation and postoperative heart block, she underwent successful surgery and pacemaker implantation, with both mother and fetuses remaining stable. DISCUSSION: Optimal timing of surgery is crucial, considering fetal developmental vulnerability in the first trimester and maternal cardiac workload in the third trimester. Second-trimester risks are comparable to non-pregnant patients. A limited understanding of fetal-placental perfusion during bypass necessitates cautious management strategies, with emerging techniques like pulsatile perfusion showing promise. Anaesthesia selection prioritises fetal safety while monitoring fetal distress during surgery remains challenging. To achieve successful outcomes for both mother and babies in a twin pregnancy undergoing a redo aortic valve replacement, careful timing, appropriate surgical techniques, and meticulous perioperative care are essential. CONCLUSION: A multidisciplinary approach is crucial for managing twin pregnancy following redo aortic valve surgery. Careful planning, close monitoring, and specialised surgical and anaesthetic techniques are key to minimising risks to both mother and fetus.

Defibrillation strategies for patients with refractory ventricular fibrillation: A systematic review and meta-analysis.

AIM: The aim of this study was to summarize the existing evidence about the effectiveness of double defibrillation (DD) in comparison to standard defibrillation for patients with refractory ventricular fibrillation (RVF). DD encompasses double "sequential" external defibrillation (DSeq-D) and double "simultaneous" defibrillation (DSim-D), with the study also shedding light on the respective effects of DSeq-D and DSim-D. METHODS: Investigators systematically searched PubMed, EMBASE and Cochrane Central databases for randomized controlled trials (RCTs) and cohort studies from their inception until June 06, 2024. The rate of survival to hospital discharge was the primary outcome, while the incidence of return of spontaneous circulation (ROSC), termination of ventricular fibrillation (VF), survival to hospital admission and good neurologic outcome were secondary outcomes. Relative ratios (RR) and 95% confidence intervals (CIs) were calculated for each outcome. Heterogeneity was assessed using I square value. RESULTS: A total of 6 trials, comprising 1360 patients, were included. One was an RCT, and five were observational cohort studies. The RCT showed that, compared to standard defibrillation, DSeq-D was associated with higher incidences of survival to hospital discharge, termination of VF, ROSC and good neurologic outcome. However, the pooled results of cohort studies found no benefit of DD over standard defibrillation in survival to hospital discharge (RR, 0.91; 95% CI, 0.46-1.78), nor in secondary outcomes. Furthermore, subgroup analysis suggested DSim-D was linked with lower ROSC rate compared to standard defibrillation (RR, 0.65; 95% CI, 0.49-0.86), while there was no significance between DSeq-D and standard defibrillation (RR, 1.00; 95% CI, 0.70-1.42). CONCLUSIONS: The benefit of DSeq-D in survival to hospital discharge for RVF patients was found in the RCT, but not in cohort studies. Additionally, DSim-D should be applied with greater caution for RVF patients. Further validation is needed through larger-scale and higher-quality trials. TRIAL REGISTRY: INPLASY; Registration number: INPLASY202340015; URL: https://inplasy.com/.