Lateral atrial septal defect closure with induced ventricular fibrillation versus cardioplegic arrest.

Minimally invasive surgical closure of atrial septal defects is gaining widespread acceptance and can be performed via a right midaxillary thoracotomy. In addition, the procedure can be performed in ischaemic cardiac arrest or fibrillation with a core body temperature between 34-36 °C. OBJECTIVES: We present our single-center results of paediatric patients who underwent surgical ASD II closure via lateral thoracotomy. METHODS: Retrospective analysis. Patients were divided into a cardiac arrest group and a cardiac fibrillation group. All procedures were performed via right midaxillary thoracotomy through a single incision without side ports. RESULTS: All 37 consecutive patients between 03/2019 and 08/2022 (median age 3 years; percentile 25th: 2; 75th: 5 years) in both groups were free of mortality and postoperative morbidity such as haemodynamically relevant residual shunt or malignant arrhythmias. Cardiopulmonary bypass time was significantly shorter in the fibrillation group (mean: 34.7 min. Vs 52.6 min., p 0.01), all patients were weaned off the ventilator immediately postoperatively. Length of ICU stay was not different between the two groups. Postoperative hospital stay was significantly longer in patients with cardiac arrest (mean: 5.6 days vs 4.9 days, p 0.04). Postoperative laboratory parameters did not differ between the two groups. All patients were discharged with normal left ventricular function and normalized cardiac enzymes. CONCLUSIONS: Minimally invasive closure of an atrial septal defect during atrial fibrillation is a safe procedure with results comparable to those of an induced cardiac arrest procedure.

Coronary Vasospasm Presenting in a Catastrophic Way.

Coronary artery vasospasm is an under-recognized yet fatal condition that can manifest as sudden cardiac arrest. A 51-year-old man presented with out-of-hospital cardiac arrest due to ventricular fibrillation during exercise. Coronary angiogram showed severe disease at ostial left main coronary artery and left anterior descending artery (LAD), that was not present anymore on repeated angiography and intravascular ultrasound assessment. Cardiac magnetic resonance demonstrated evidence of prior myocardial infarction in the LAD territory. Acetylcholine challenge test was performed that induced severe left main coronary artery and LAD spasm. Coronary artery vasospasm has contributed to a significant proportion of patients presenting with coronary artery disease. Establishing the correct diagnosis is detrimental to future management of patients. This case highlighted a multimodality approach in the diagnosis of coronary vasospasm.

Ventricular Fibrillation Cardiac Arrest With Endocarditis During Pregnancy.

A 34-year-old pregnant woman collapsed at home without preceding symptoms. Following bystander cardiopulmonary resuscitation, ventricular fibrillation was documented and successfully reverted with an external shock. The electrocardiogram showed sinus rhythm, right bundle branch block, ST-segment depression, and T-wave inversion in anterior leads. She was then brought to the hospital for emergency management.

2 Rare Syndromes in 1 Patient: Determining the Cause of Sudden Cardiac Arrest.

A 19-year-old man survived sudden cardiac arrest caused by ventricular fibrillation during physical activity. The initial suspicion that this was caused by electrolyte imbalance proved to be wrong. Cardiac computed tomography revealed congenital heart disease. Coronary imaging is an essential component of the comprehensive diagnostic workup after sudden cardiac arrest.

Coronary artery compression by dilated pulmonary artery in an early infantile case of tetralogy of Fallot with absent pulmonary valve: ventricular fibrillation as the initial symptom of myocardial ischaemia.

Coronary artery compression by a dilated pulmonary artery is a rare complication in patients with tetralogy of Fallot with absent pulmonary valve. We present a case in which this condition manifested at two months of age, with ventricular fibrillation as the initial symptom of myocardial ischaemia. It is important to recognise that this potentially fatal complication can occur in early infancy.

Out-of-Hospital Cardiac Arrest Outcomes After Ventricular Fibrillation.

INTRODUCTION:  This study is a retrospective review of patients who sustained out-of-hospital cardiac arrest due to ventricular fibrillation. The data were analyzed to decipher predictors of good outcomes as the overall survival rate in the county is significantly higher than the national average. METHODS: The inclusion criteria for the study comprised all patients over the age of 18 for whom a call was made for unresponsiveness. Data for this project included all cardiac arrests due to ventricular fibrillation in the calendar year 2022.  Results: A total of 80 patients sustained cardiac arrest due to ventricular fibrillation. The age range was 27-80 years old. The study has 71% White, 19% African American, 8.7% Hispanic, and 1% other populations. Ninety-five percent received epinephrine, 89% utilized an advanced airway, 60% underwent hypothermia protocol, 24% utilized an AED device, and 14% used a mechanical CPR device. Seventy-six percent were pronounced dead in the ER or the hospital, and 19% survived to discharge. In the survivor population, CPR was initiated in 13 minutes or less and defibrillation occurred in 23 minutes or less. While none of the variables achieved statistical significance, epinephrine use showed a trend toward statistical significance for the outcome of sustained return of spontaneous circulation (ROSC) with a p-value of 0.05346. CONCLUSION: Nineteen percent of patients survived out-of-hospital cardiac arrests in the Polk County hospital system. This is significantly higher than the national average. This likely reflects the emphasis on high-quality CPR and active on-scene management, as no individual variable was statistically significant.

Pacing-facilitated Short-long-short Sequences Leading to Ventricular Tachyarrhythmias: A Brief Report.

Pacing-induced recurrent short-long-short sequences constitute an important yet overlooked mechanism for triggering ventricular tachyarrhythmias in patients with cardiovascular implantable electric devices. A careful and thorough retrospective analysis of patients' electrograms allows for a timely diagnosis with appropriate management.

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.

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.

High predicted durability for the novel small-diameter OmniaSecure defibrillation lead.

BACKGROUND: Defibrillation leads remain the Achilles heel of implantable cardioverter-defibrillators. As patients with implantable cardioverter-defibrillators are living longer and battery longevity increases, more durable leads are needed. The LEADR trial evaluated the novel, lumenless, small-diameter, OmniaSecure defibrillation lead and demonstrated favorable safety and efficacy profile as well as zero fractures through 12.7 ± 4.8 months and remains in clinical follow-up. To augment the clinical trial, advanced cardiac lead reliability modeling was used to project long-term lead durability. OBJECTIVE: We aimed to project the 10-year fracture-free survival of the OmniaSecure defibrillation lead using reliability modeling. METHODS: The validated reliability model, which incorporates patient and bench test data, was used to project the 10-year fracture-free survival of the OmniaSecure lead. A subset of LEADR trial patients underwent biplane fluoroscopy imaging during cardiac and patient motion to evaluate the lead's bending curvature in vivo. Bench tests then reproduced these use conditions with greater bending curvatures than observed in patients to exaggerate stress on the lead and to evaluate the lead fatigue strength. RESULTS: The reliability modeling projects a 98.2% fracture-free survival rate of the OmniaSecure lead at 10 years, including a 10-year fracture-free survival rate of 97.9% in adolescents, exceeding both the modeled and clinical 10-year performance of the highly reliable, larger diameter Sprint Quattro lead. CONCLUSION: Consistent with early clinical trial experience, modeling projects highly durable 10-year performance of the OmniaSecure lead, including within the active adolescent pediatric population, which may uniquely benefit from a novel 4.7F defibrillation lead designed for reliability. GOV IDENTIFIER: NCT04863664.

Ventricular fibrillation arrest in aortic dissection presenting as myocardial injury.

An acute aortic dissection can be a tremendously fatal vascular condition if not managed promptly. However, the symptom profile of aortic dissections can be ambiguous to numerous conditions which are more common and greater pursued by clinicians before suspicion of dissection is made. The case presented in this study is of a 61-year-old male who arrives to the emergency department for concern of new-onset chest pain which progresses into ventricular fibrillation arrest prior to diagnosis of aortic dissection. This case report profiles the mimicking possibility of aortic dissection to present as acute myocardial injury, and the utility of models use to differentiate the workup between aortic dissections and acute coronary syndromes.

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.

Graves' Disease Associated With Pulmonary Hypertension and Cardiac Arrest.

Thyrotoxicosis has been associated with several cardiac conditions including atrial fibrillation, congestive heart failure due to left ventricular dysfunction, and cardiomyopathy. However, few cases of ventricular fibrillation as a complication of thyrotoxicosis have been reported. Our case described a 45-year-old male with a history of hypertension and Graves' disease, who presented with 1 week of left-sided chest pain associated with shortness of breath on exertion and occasional palpitations. His workup revealed acute diastolic congestive heart failure secondary to thyrotoxicosis, causing pulmonary hypertension, which led to ventricular fibrillation and cardiac arrest. After being treated with methimazole and metoprolol, the patient's symptoms improved. This case underscores the significance of assertive medical interventions alongside both invasive and non-invasive cardiac procedures. Addressing thyrotoxicosis and ventricular arrhythmia in hyperthyroid patients is crucial to prevent potentially life-threatening complications.

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 < .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 = .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.

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% of patients] female patients; median age, 45 years [interquartile range: 36, 59]; n=14 [100% of patients] 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.

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.