Management Of Arrhythmias Research Articles

Anatomy and Pathology of the Cardiac Conduction System.

The cardiac conduction system is formed of histologically and electrophysiologically distinct specialized tissues uniquely located in the human heart. Understanding the anatomy and pathology of the cardiac conduction system is imperative to an interventional electrophysiologist to perform safe ablation and device therapy for the management of cardiac arrhythmias and heart failure. The current review summarizes the normal and developmental anatomy of the cardiac conduction system, its variation in the normal heart and congenital anomalies, and its pathology and discusses important clinical pearls for the proceduralist.

Atrial Arrhythmias in Adults with Fontan Palliation.

Single ventricle physiology is a rare form of congenital heart disease and was, historically, a uniformly lethal condition. However, the atriopulmonary Fontan operation, and its successive iterations, the lateral tunnel and extracardiac conduit Fontan, became the fundamental approach to treating single ventricle heart disease. Over time, dysrhythmias are some of the most common complications with Fontan physiology, compounding morbidity and mortality. Atrial arrhythmias are prevalent in the Fontan population and occur in about 15-60% of patients with Fontan palliation, increasingly with age. Diagnosing atrial arrhythmias in patients with Fontan palliation may be challenging because of low voltage amplitudes arising from myopathic atrial tissue making it difficult to clearly assess atrial depolarization on surface electrocardiograms (ECG), vague symptoms not suggestive of tachyarrhythmia, or atrial arrhythmia with ventricular rates below 100beats per minute. Intra-atrial reentrant tachycardia (IART) is the most common type of supraventricular tachycardia in adults with Fontan palliation. Acute management of atrial arrhythmias in patients with Fontan palliation involves prompt assessment of a patient's hemodynamic stability, anticoagulation and thrombosis risk, systemic ventricular function, and risk of sedation or anesthesia if needed. Long-term management of atrial arrhythmias is often multifactorial and may include long-term anti-arrhythmic therapy, permanent pacing, and ablation. The best approach for the management of atrial arrhythmias in adults with Fontan palliation is patient-specific and involves collaboration between congenital electrophysiologists, adult congenital cardiologists, and the patient.

Practical guidance to reduce radiation exposure in electrophysiology applying ultra low-dose protocols: a European Heart Rhythm Association review.

Interventional electrophysiology offers a great variety of treatment options to patients suffering from symptomatic cardiac arrhythmia. Catheter ablation of supraventricular and ventricular tachycardia has globally evolved a cornerstone in modern arrhythmia management. Complex interventional electrophysiological procedures engaging multiple ablation tools have been developed over the past decades. Fluoroscopy enabled interventional electrophysiologist throughout the years to gain profound knowledge on intracardiac anatomy and catheter movement inside the cardiac cavities and hence develop specific ablation approaches. However, the application of X-ray technologies imposes serious health risks to patients and operators. To reduce the use of fluoroscopy during interventional electrophysiological procedures to the possibly lowest degree and to establish an optimal protection of patients and operators in cases of fluoroscopy is the main goal of modern radiation management. The present manuscript gives an overview of possible strategies of fluoroscopy reduction and specific radiation protection strategies.

Overview of Cardiac Arrhythmias and Treatment Strategies.

Maintenance of normal cardiac rhythm requires coordinated activity of ion channels and transporters that allow well-ordered propagation of electrical impulses across the myocardium. Disruptions in this orderly process provoke cardiac arrhythmias that may be lethal in some patients. Risk of common acquired arrhythmias is increased markedly when structural heart disease caused by myocardial infarction (due to fibrotic scar formation) or left ventricular dysfunction is present. Genetic polymorphisms influence structure or excitability of the myocardial substrate, which increases vulnerability or risk of arrhythmias in patients. Similarly, genetic polymorphisms of drug-metabolizing enzymes give rise to distinct subgroups within the population that affect specific drug biotransformation reactions. Nonetheless, identification of triggers involved in initiation or maintenance of cardiac arrhythmias remains a major challenge. Herein, we provide an overview of knowledge regarding physiopathology of inherited and acquired cardiac arrhythmias along with a summary of treatments (pharmacologic or non-pharmacologic) used to limit their effect on morbidity and potential mortality. Improved understanding of molecular and cellular aspects of arrhythmogenesis and more epidemiologic studies (for a more accurate portrait of incidence and prevalence) are crucial for development of novel treatments and for management of cardiac arrhythmias and their consequences in patients, as their incidence is increasing worldwide.

Atrial Fibrillation Detection Using Electrocardiogram Signal Input to LMD and Ensemble Classifier

Atrial fibrillation (AFib) is a type of heart arrhythmia, marked by an erratic and rapid contraction of the atria. Computer-aided diagnosis of AFib using electrocardiogram (ECG) sensor data may become a valuable tool in the detection and management of this common cardiac arrhythmia. In this letter, we present a new hybrid approach for the automatic classification of ECG signals using the local mean decomposition (LMD) and ensemble boosted trees classifier (EBTC). The LMD algorithm is employed to adaptively decompose the recorded ECG data into product functions (PFs). Four entropy-based features namely, log energy, sure, Shannon, and threshold entropy are computed from each PFs. The Kruskal-Wallis algorithm is employed to check the statistical significance of the obtained features and an EBTC is used for the screening of AFib episodes. The proposed technique achieved the highest classification accuracy of 92.33%, 90.33%, and 90.00% by classifying immediate terminating and non-terminating, terminates after one minute and non-terminating, immediate terminating and terminates after one minute AFib episodes, respectively. The presented method outperforms the existing machine learning-based approaches for detecting AFib using ECG data acquired from the publicly accessible AF Termination Challenge Database.

Editorial on “Management of Cardiac Arrhythmia—Broadening the Horizons of Surgical Interventions”

Editorial on “Management of Cardiac Arrhythmia—Broadening the Horizons of Surgical Interventions”

Pathophysiology and treatment of adults with arrhythmias in the emergency department, part 2: Ventricular and bradyarrhythmias.

In an effort to expedite the publication of articles, AJHP is posting manuscripts online as soon as possible after acceptance. Accepted manuscripts have been peer-reviewed and copyedited, but are posted online before technical formatting and author proofing. These manuscripts are not the final version of record and will be replaced with the final article (formatted per AJHP style and proofed by the authors) at a later time. This is the second article in a 2-part series reviewing the pathophysiology and treatment considerations for arrhythmia. Part 1 of the series discussed aspects related to treating atrial arrhythmias. Here in part 2, the pathophysiology of ventricular arrhythmias and bradyarrhythmias and current evidence on treatment approaches are reviewed. Ventricular arrhythmias can arise suddenly and are a common cause of sudden cardiac death. Several antiarrhythmics may be effective in management of ventricular arrhythmias, but there is robust evidence to support the use of only a few of these agents, and that evidence was largely derived from trials involving patients with out-of-hospital cardiac arrest. Bradyarrhythmias range from asymptomatic mild prolongation of nodal conduction to severe conduction delays and impending cardiac arrest. Vasopressors, chronotropes, and pacing strategies require careful attention and titration to minimize adverse effects and patient harm. Ventricular arrhythmias and bradyarrhythmias can be consequential and require acute intervention. As experts in pharmacotherapy, acute care pharmacists can participate in providing high-level intervention by aiding in diagnostic workup and medication selection.

Management of cardiac arrhythmias in paediatric patients with TANGO2-deficiency disorder

Abstract Funding Acknowledgements Type of funding sources: None. Background TANGO2-deficiency disorder (TDD) is a rare paediatric condition caused by bi-allelic mutations in the TANGO2 gene. TDD is characterised by susceptibility to metabolic crises with rhabdomyolysis, encephalopathy, lactic acidosis, hypothyroidism and difficult to manage tachyarrhythmias. Aim We describe the electrocardiographic (ECG) findings at baseline and during metabolic crises in patients with TDD. Methods Retrospective, single-centre, case series study of patients with TDD (<18 years), with ECG and subcutaneous Holter monitoring, both during metabolic crises and compensated phases. Results During the period 2013-2021, 12 patients with TDD were found (median age 6.8 years, IQR 2-11.5 years). In the inter-crisis period, bradyarrhythmias were evidenced: 2/12 patients presented sinus bradycardia, 2/12 pauses of 4 and 10 seconds, 1/12 Wenckebach type block; and tachyarrhythmias: 1/12 presented paroxysmal supraventricular tachycardia and 1/12 flutter. 25% had long QT during non-acute phases (median QTc max 476 ms, IQR 456ms-530ms). There were 14 hospitalisations for metabolic crises. 57.1% had QTc interval prolongation, 35.7% ventricular tachycardias (4/14 monomorphic VT, 1/14 torsade de prongs) and 1/14 Brugada type 3 pattern. Three patients died in the context of severe metabolic acidosis and multi-organ involvement (2/12 due to VT and 1/12 due to cardiogenic shock, bradycardia associated with QTc of 635ms and severe ventricular dysfunction). Conclusions In paediatric patients with TDD, the most frequent ECG abnormality was QTc interval prolongation with or without metabolic crises. There is a high risk of tachyarrhythmias, mainly VT, being the main cause of death in children with TDD. Subcutaneous Holter monitoring is recommended. During metabolic crises, there should be close ECG monitoring.

Monitoring for arrhythmia in transthyretin cardiac amyloidosis with remote patch devices

Abstract Funding Acknowledgements Type of funding sources: None. Background/Introduction Transthyretin cardiac amyloidosis (ATTR-CA) is associated with an increased incidence of arrhythmias. We hypothesized that non-invasive, two-week outpatient cardiac rhythm monitoring of patients with ATTR-CA would detect high rates of ventricular tachycardia and atrial fibrillation/flutter (AF). Purpose To characterize arrhythmia in patients with ATTR-CA on two-week, non-invasive cardiac rhythm monitors. Methods 38 patients with ATTR-CA (mean age 76.9 SD 10.0 years, 89.5% male) who underwent two-week remote external patch monitoring were included in this single center retrospective study. An age-matched control group included 38 patients (mean age 73.9 SD 12.3, 76.3% male) who underwent the same cardiac rhythm monitoring as part of neurological workups. Results NSVT was detected on the remote monitor in 81.6% of ATTR-CA patients and AF was detected in 26.3% of patients. ATTR-CA was associated with higher rates of NSVT and AF compared to the control group (28.9% with NSVT and 5.3% with AF). As seen in Figure 1, there were only three ATTR-CA patients without either AF, NSVT, advanced atrioventricular block, or a significant pause detected on remote monitor. Among the ATTR-CA group, at median 45 weeks follow-up, there were 4 heart failure hospitalizations, 2 cardiovascular events (1 episode of sustained VT and 1 stroke), 6 permanent pacemakers placed, and 3 implantable cardioverter-defibrillators placed, including one for sustained VT. NSVT and AF were not associated with a composite of these adverse outcome. Conclusion ATTR-CA was associated with high rates of NSVT and AF on noninvasive remote monitors. While evidence regarding the management of arrhythmias, particularly NSVT/VT, in ATTR-CA remains limited, two-week noninvasive cardiac monitoring can be considered to aid in risk stratification for both atrial and ventricular arrhythmias in ATTR-CA.

Drug management of atrial fibrillation in light of guidelines and current evidence: an Italian Survey on behalf of Italian Association of Arrhythmology and Cardiac Pacing.

Atrial fibrillation is a multifaceted disease requiring personalized treatment, in accordance with current ESC guidelines. Despite a wide range of literature, we still have various aspects dividing the opinion of the experts in rate control, rhythm control and thromboembolic prophylaxis. The aim of this survey was to provide a country-wide picture of current practice regarding atrial fibrillation pharmacological management according to a patient's characteristics. Data were collected using an in-person survey that was administered to members of the Italian Association of Arrhythmology and Cardiac Pacing. We collected data from 106 physicians, working in 72 Italian hospitals from 15 of 21 regions. Our work evidenced a high inhomogeneity in atrial fibrillation management regarding rhythm control, rate control and thromboembolic prophylaxis in both acute and chronic patients. This element was more pronounced in settings in which literature shows a lack of evidence and, consequently, the indications provided by the guidelines are weak or absent. This National survey evidenced a high inhomogeneity in current approaches adopted for atrial fibrillation management by a sample of Italian cardiologist experts in arrhythmia management. Further studies are needed to explore if these divergences are associated with different long-term outcomes.

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

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

T-wave alternans: an ominous pattern for malignant arrhythmias.

We report on a patient with a history of chronic heart failure caused by atrial fibrillation, who developed macrovolt T-wave alternans (TWA) and subsequent malignant arrhythmia after amiodarone treatment. The presence of TWA and QT alternans disappeared after discontinuation of amiodarone and appropriate magnesium replacement. Macroscopic T-wave alternans (TWA) is present when there is visible variation in the amplitude and/or polarity of T waves between beats in the absence of QRS alternans. TWA signifies significant vulnerability during repolarization and may be a harbinger of impending electrical instability. Although macroscopic TWA is not frequently encountered in routine clinical practice. Prompt identification is essential for proper management and prevention of malignant ventricular arrhythmias and sudden cardiac death.

Proarrhythmia associated with antiarrhythmic drugs: a comprehensive disproportionality analysis of the FDA adverse event reporting system.

Objective: This study aimed to identify the different associations between antiarrhythmic drugs (AADs) and arrhythmias, and to determine whether pharmacokinetic drug interactions involving AADs increase the risk of AAD-related arrhythmias compared to using AADs alone. Materials and methods: The disproportionality analysis of AAD-associated cardiac arrhythmias, including AAD monotherapies and concomitant use of pharmacokinetic interacting agents involving AADs, was conducted by using reporting odds ratio (ROR) and information component (IC) as detection of potential safety signals based on FAERS data from January 2016 to June 2022. We compared the clinical features of patients reported with AAD-associated arrhythmias between fatal and non-fatal groups, and further investigated the onset time (TTO) following different AAD regimens. Results: A total of 11754 AAD-associated cardiac arrhythmias reports were identified, which was more likely to occur in the elderly (52.17%). Significant signals were detected between cardiac arrhythmia and all AAD monotherapies, with ROR ranging from 4.86 with mexiletine to 11.07 with flecainide. Regarding four specific arrhythmias in High Level Term (HLT) level, the AAD monotherapies with the highest ROR were flecainide in cardiac conduction disorders (ROR025 = 21.18), propafenone in rate and rhythm disorders (ROR025 = 10.36), dofetilide in supraventricular arrhythmias (ROR025 = 17.61), and ibutilide in ventricular arrhythmias (ROR025 = 4.91). Dofetilide/ibutilide, ibutilide, mexiletine/ibutilide and dronedarone presented no signal in the above four specific arrhythmias respectively. Compared with amiodarone monotherapy, sofosbuvir plus amiodarone detected the most significantly increased ROR in arrhythmias. Conclusion: The investigation showed the spectrum and risk of AAD-associated cardiac arrhythmias varied among different AAD therapies. The early identification and management of AAD-associated arrhythmias are of great importance in clinical practice.

PO-04-140 ARRHYTHMIA PRESENTATION AND MANAGEMENT IN PATIENTS WITH CLINICALLY DIAGNOSED CARDIAC SARCOIDOSIS

The diagnosis of cardiac sarcoidosis (CS) is often suspected based on clinical features when histologic evidence is lacking. While the arrhythmic characteristics of CS with histologic evidence meeting the 2014 Heart Rhythm Society criteria (definite or probable CS) have been extensively studied, the arrhythmic presentations and outcomes of clinical CS are less known. To compare arrhythmia manifestations, management, and outcomes between clinically diagnosed and definite/probable CS. We retrospectively analyzed a single-center referral cohort of patients with available electrophysiologic data stratified by CS category (definite/probable or clinical). Patients with clinical CS had no histologic evidence of cardiac or extracardiac sarcoidosis (biopsy negative or not performed) and the diagnosis was based on clinical course (unexplained sustained VT, Mobitz II, or complete AV block) and imaging features (patchy uptake on dedicated cardiac positron emission tomography or late gadolinium enhancement on cardiac magnetic resonance imaging). History of arrhythmias at index evaluation, arrhythmia management, and outcomes were comparatively assessed for patients with definite/probable CS compared to those with clinical CS. The cohort included 629 CS patients (median age 57 years, male 67%, NYHA class I-II 78%), including 12% definite, 54% probable, and 34% clinical CS patients. History of ventricular and supraventricular arrhythmias was more common in clinical CS compared to definite/probable CS (Figure). Accordingly, the rate of antiarrhythmic drug use was higher in clinical (33%) than definite/probable CS (22%, p=0.002). Median follow-up after index evaluation at our institution was 3.1y (IQR 4.2y). The number of incident VT/VF events per patient per year was greater in clinical CS than definite/probable CS (Figure). Catheter ablations for ventricular arrhythmia were more frequent in clinical CS (27%) than definite/probable CS (9%, p<0.001). Patients with clinical CS exhibited a more severe arrhythmic phenotype compared to patients with definite/probable CS. These findings have implications for the management and prognosis of CS patients within this common clinical category.

AP-453071-3 IMPACT OF SEX ON OUTCOMES FOLLOWING AEROBIC EXERCISE TRAINING IN PATIENTS WITH SYMPTOMATIC ATRIAL FIBRILLATION

Aerobic exercise prescription promotes the maintenance of sinus rhythm in patients with atrial fibrillation (AF). There is little data exists on whether this may be modified by patient sex. Compare outcoes between male and female patents amongst a randomized controlled trial of aerobic exercise prescription for patients with symptomatic AF. This study was a prospective, randomized, controlled trial of patients with symptomatic paroxysmal or persistent AF, referred for consideration of AF ablation. Randomization was 1:1 to either aerobic exercise intervention or usual medical care for a period of 6 months with a further 6 months follow-up. The exercise intervention was delivered in a hybrid format of weekly supervised exercise sessions coupled with prescribed home exercise, up to a total of 210 minutes per week. The intervention was led by a clinical exercise physiologist. Management of arrhythmia was at the discretion of a cardiologist blinded to patient randomization. The primary endpoint reported here is recurrent AF without rhythm control strategies. Of the 120 patients enrolled in the study (65±10 years, BMI 30±6, 38% Persistent AF), 51 were female (42.5%). Female patients were less likely to have persistent AF at baseline (19.6%) compared to males (47.8%), had comparable BMI (30.8 v 30.2 kg/m2), were older (68±7 v 63±11 years) and had lower baseline peak oxygen uptake (16±4 v 23±5mL/kg/min, p<0.001). After 12-mnths of follow-up, both male (HR 0.52, 95% CI: 0.29-0.91) and female patients (HR 0.47, 95% CI: 0.23-0.95) in the exercise group had reduced recurrence of AF without anti-arrhythmic medication or AF ablation. Although male and female patients exhibit baseline differences in risk factor profile, aerobic exercise training is equally effective in males and females for the reduction of recurrent arrhythmia amongst patients with symptomatic atrial fibrillation.

CI-452770-1 USE OF ARTIFICIAL INTELLIGENCE ALGORITHMS TO REDUCE TRANSMISSIONS IN IMPLANTABLE LOOP RECORDERS

Implantable loop recorders (ILRs) are frequently used for arrhythmia diagnosis and management. Remote monitoring (RM) facilitates earlier response to alerts. However, this has resulted in significant increase in clinic workloads due to growing alert burden. A large component of this excess workload has related to inaccuracies related to artefact or over-sensing. The use of artificial intelligence (AI) may help to reduce and streamline workflow. To assess the impact of the AccuRhythmTM in a large independent remote monitoring dataset to determine the impact on the number of transmissions and the how the implementation of AI has improved the burden of downloads from Medtronic LINQ II. The AccuRhythmTM AI algorithm applies deep learning algorithms to the LINQ II data addressing false alerts. For this study, the PaceMateTM RM system was utilized. This system is a partially automated, vendor-neutral RM software system. The system presents RM data acquired from all vendors in a standardized format and includes all RM alerts transmitted by CIED patients undergoing RM via PaceMate LiveTM. All patients, who transmitted at least one episode during the one-month period before (January 2022) and after (April 2022) implementation of the AccuRhythmTM AI algorithm were evaluated. We included 661 patients with a mean age of 64.9±15.4 years who transmitted in both January and April. There was a statistically significant reduction in alerts transmitted per patient from January (ranging from 0 to 63 alerts per patient; mean 1.4, median 0, IQR=1) compared to after activation of the AI algorithm in April (range 0 to 36 alerts per patient; mean 0.98, median 0, IRQ=1; p<0.001). (Figure) This represented a 20.4% reduction in alerts per patient with the AI algorithm. In addition to the reduction in alerts transmitted, there was also a significant reduction in the number of episodes per patient attached to each transmission from January (range 0 to 211 episodes per patient; mean 4.5, median 0, IQR=3) compared to April (range 0 to 110 episodes per patient; mean 3.9, median 0, IQR=1; p<0.001), (Figure) representing a 39.7% reduction in episodes per patient with the AI algorithm. The implantation of an AI algorithm for LINQ II devices, significantly reduced alert burden by 20% and episode burden by 40% in a large, unselected group of patients. The implementation of AI algorithms have an essential role in facilitating the reduction of clinic workloads due to RM.

PO-04-103 WIDE COMPLEX TACHYCARDIA IN ACUTE ANTI-NMDA RECEPTOR ENCEPHALITIS

NA NA NA A 20-year-old male with no known past medical history presented with two months of episodic right-sided weakness. An extensive workup was notable for a lumbar puncture that was positive for antibodies to the N-methyl-D-aspartate (NMDA) receptor, confirming anti-NMDA receptor (NMDAR) encephalitis. Baseline cardiac workup included a transthoracic echocardiogram (TTE) that showed left ventricular (LV) hypokinesis with borderline ejection fraction (EF 52%), and an ECG showing sinus tachycardia (Figure-A). While admitted, the patient developed shock, necessitating intubation and vasopressors. Serial ECGs while in shock showed sinus tachycardia, a prolonged QTc, and broad sail-like T wave in V1 (similar to type 1 Brugada pattern), with ST elevations in aVR and diffuse ST depressions inferolaterally (Figure-B). Serial troponins were minimally elevated (0.11 ug/L) and TTE showed no regional wall motion abnormalities, so invasive coronary angiography was not pursued. During progressive shock, the patient developed a wide complex tachycardia (WCT, Figure-C), that was thought to most likely be LV outflow tract ventricular tachycardia. The patient became hemodynamically unstable with the WCT, necessitating amiodarone, lidocaine, and ultimately five cardioversions. Repeat TTE showed severe biventricular dysfunction, and the patient needed veno-arterial extracorporeal membrane oxygenation (VA-ECMO). Ultimately, the patient’s biventricular function recovered, and he was able to be decannulated from VA-ECMO. He was managed with intravenous immunoglobulin, steroids and rituximab for his anti-NMDAR encephalitis. Cardiac arrhythmias are a known complication of anti-NMDAR encephalitis in up to one-third of patients. To the best of our knowledge, this is the first case of anti-NDMAR encephalitis associated with diffuse ST elevations suggestive of ischemia. Models suggest NMDA receptor-mediated signaling in the nervous system can alter the vagal outflow to the heart, leading to sinus brady/tachycardia. Other explanations for ECG changes in our patient include focal myocarditis/vasospasm. This is an unusual case of marked ST elevation and sustained VT in anti-NMDAR encephalitis. Pathogenesis and management of arrhythmias related to this condition warrant further study.

Transplacental Treatment of Fetal Tachyarrhythmia: Current Trends and Future Perspectives

Fetal arrhythmias complicate 1% of pregnancies. Although most of them have a benign and intermittent course, sustained fetal tachyarrhythmias constitute an emerging situation, which is associated with high fetal morbidity and mortality. However, one of the major milestones in fetal therapy is the pharmacologic management of fetal arrhythmias by crossing the placental barrier. To date, there is no consensus on the first-line antiarrhythmic treatment for fetal tachyarrhythmias. The role of sotalol in therapeutic management, the use of flecainide versus digoxin as first line of treatment, the need for fetal intramuscular treatment administration, or the best treatment in case of fetal hydrops are situations whose application or management are controversial. The current paper is a scoping review of observational and experimental evidence, addressing the types of best management strategies for each type of tachyarrhythmia and the optimal pharmacological dose, considering precautions and safety elements. Finally, we will highlight new therapeutic perspectives and future diagnostic and therapeutic strategies.

Sudden Cardiac Death: An Update on Commotio Cordis.

Sudden cardiac death (SCD) is one of the leading causes of cardiovascular mortality, and it is caused by a diverse array of conditions. Among these is commotio cordis, a relatively infrequent but still significant cause, often seen in young athletes involved in competitive or recreational sports. It is known to be caused by blunt trauma to the chest wall resulting in life-threatening arrhythmia (typically ventricular fibrillation). The current understanding pertains to blunt trauma to the precordium, with an outcome depending on factors such as the type of stimulus, the force of impact, the qualities of the projectile (shape, size, and density), the site of impact, and the timing of impact in relation to the cardiac cycle. In the management of commotio cordis,a history of preceding blunt chest trauma is usually encountered. Imaging is mostly unremarkable except for ECG, which may show malignant ventricular arrhythmias. Treatment is focused on emergent resuscitation with the advanced cardiac life support protocol algorithm, with extensive workup following the return of spontaneous circulation. In the absence of underlying cardiovascular pathologies, implantable cardiac defibrillator insertion is not beneficial, and patients can even resume physical activity if the workup is unremarkable. Proper follow-up is also key in the management and monitoring of re-entrant ventricular arrhythmias, which are amenable to ablative therapy. Prevention of this condition involves protecting the chest wall against blunt trauma, especially with the use of safety balls and chest protectors in certain high-risk sporting activities. This study aims to elucidate the current epidemiology and clinical management of SCD with a particular focus on a rarely explored etiology, commotio cordis.

Stereotactic Arrhythmia Radioablation Treatment of Ventricular Tachycardia: Current Technology and Evolving Indications

Ventricular tachycardia in patients with structural heart disease is a significant cause of morbidity and mortality. According to current guidelines, cardioverter defibrillator implantation, antiarrhythmic drugs, and catheter ablation are established therapies in the management of ventricular arrhythmias but their efficacy is limited in some cases. Sustained ventricular tachycardia can be terminated by cardioverter-defibrillator therapies although shocks in particular have been demonstrated to increase mortality and worsen patients' quality of life. Antiarrhythmic drugs have important side effects and relatively low efficacy, while catheter ablation, even if it is actually an established treatment, is an invasive procedure with intrinsic procedural risks and is frequently affected by patients' hemodynamic instability. Stereotactic arrhythmia radioablation for ventricular arrhythmias was developed as bail-out therapy in patients unresponsive to traditional treatments. Radiotherapy has been mainly applied in the oncological field, but new current perspectives have developed in the field of ventricular arrhythmias. Stereotactic arrhythmia radioablation provides an alternative non-invasive and painless therapeutic strategy for the treatment of previously detected cardiac arrhythmic substrate by three-dimensional intracardiac mapping or different tools. Since preliminary experiences have been reported, several retrospective studies, registries, and case reports have been published in the literature. Although, for now, stereotactic arrhythmia radioablation is considered an alternative palliative treatment for patients with refractory ventricular tachycardia and no other therapeutic options, this research field is currently extremely promising.