Episodes Of Ventricular Arrhythmias Research Articles

Renal denervation for the management of refractory ventricular arrhythmias

Abstract Background While catheter ablation (CA) has proven effective in managing ventricular arrhythmias (VA) associated with structural heart disease, a portion of patients continue to experience refractory VA despite medical treatment and multiple CA procedures. In such cases, additional techniques, such as autonomic neuromodulation, have been explored. Renal denervation (RDN), traditionally performed for the treatment of resistant arterial hypertension, inhibits the afferent renal sympathetic pathway, leading to reduced efferent sympathetic overactivation on a systemic level. Due to this mechanism, it has also been studied for the management of arrhythmias, including atrial fibrillation and VA, with favorable results. Objective To assess the effectiveness and safety of RDN for the management of refractory VA storms in high-risk patients. Methods A retrospective analysis of RDN procedures for electrical storms, conducted at a tertiary center between February 2020 and September 2023. We analyzed baseline patient characteristics, procedural details, and acute complications. Recurrence of VA after RDN was assessed at one and six months. Results A total of 7 patients underwent RDN for the treatment of refractory VA. The mean age was 56 ± 10 years (6 male). The primary diagnosis was ischemic cardiomyopathy (n=5), with a mean left ventricular ejection fraction (LVEF) of 20 ± 5%, and no history of resistant arterial hypertension. All patients had an implantable cardioverter-defibrillator (ICD) (two with concomitant resynchronization therapy). Five patients had undergone previous endocardial VA ablation. Of the two patients without prior VA ablation, one had a contraindication because of a large left ventricle thrombus, and the other was submitted to an electrophysiological study, but without inducible ventricular tachycardia. In the four weeks before RDN, patients exhibited a mean of 12 ± 18 sustained VA episodes, meeting the criteria for electrical storm (3 ≥ episodes in 24h). During the procedure, there was a mean of 7 ± 8 radiofrequency applications in the right renal artery and 6 ± 10 in the left renal artery. No acute complications were observed. One month after the procedure, VA episodes were reduced to a mean of 0 ± 1, with only two patients experiencing recurrent VA. After six months, the absence of VA recurrence remained consistent, with only one patient experiencing new episodes. There were no deaths during this period. Conclusion In our pilot study, RDN appeared to be a safe and effective treatment for the management of VA.VA episodes before and after RDN

Percutaneous stellate ganglion blockade as an add-on therapy for the treatment of arrhythmic storm

Abstract Introduction Arrhythmic storm (AS) due to repetitive ventricular arrhythmias (VA) is a life-threatening condition that can be resistant to antiarrhythmic therapy. Sympathetic nervous system plays an important role in triggering and maintaining VA. Reducing sympathetic activity by percutaneous stellate ganglion blockade (SBG) may improve outcomes in treating AS. Purpose To evaluate the effect of SBG on outcomes of AS. Methods In this retrospective study, we analyzed 18 patients treated with SBG for AS from August 2017 to May 2022. All patient experienced VA while on antiarrhythmic drug therapy. SBG was performed under ultrasound guidance to avoid vascular structures. Either 0.75% levobupivacaine or 0.5% ropivacaine were applied to block the stellate ganglion after negative aspiration. The decision to perform unilateral or bilateral SBG was left to the operator. Results The majority of patients were male (17/18, 94.4%), mean age was 61.8 ± 13.4 years, mean BMI 28.1 ± 5.39 kg/m2, mean LVEF was 34.4 ± 12.2%, majority had an ischemic cardiomyopathy (12/18, 66.7%). Half of the patients had monomorphic VA (9/18, 50.0%), the other half had polymorphic VA (9/18, 50.0%). Majority of patients were hemodynamically unstable (13/18, 72.2%) and more than a third had a cardiac arrest (7/18, 38.9%). Half of the patients had unilateral SBG (9/18, 50.0%), and the other half bilateral SBG (9/18, 50.0%). SBG was repeated in two patients (2/18, 11.1%). On the repeat procedure, both had bilateral SBG. There were 4 minor complications (4/18, 22.2%) and no major complications. Two patients had intermittent Horner’s syndrome, one had a small hematoma on the puncture site, and one had small hematoma in the mediastinum. All complications resolved on their own and did not require an intervention. In the 72 hours after SBG, 5 patients had a recurrence of VA (5/18, 27.8%). After the discharge, 6 patients also had a recurrence of VA (6/18, 44.4%). SBG significantly reduced mean number of VA episodes in the next 72 hours (12.3 ± 11.1 vs 4.3 ± 10.6; P=0.007) with a mean difference of 8.0 VA episodes (95% CI, 4.5 - 14.0; P=0.007) (Figure 1). One patient died due to recurrent VA leading to ischemic brain damage (1/18, 5.6%). Four patients died due to non-VA related causes (4/18, 22.2%). Two deaths were due to septic shock, the other two due to cardiogenic shock. Details of baseline characteristics and outcomes are in the Figure 2. Conclusion SBG significantly reduces episodes of VA after failed antiarrhythmic drug therapy in patients presenting with AS.A before-after graph of VA after SBG.Baseline and outcomes table.

Neural network for automatic ICD-EGMs matching in pace-mapping and ablation of ventricular arrhythmias

Abstract Background Mapping of the ventricular arrhythmias (VA) is often not possible due to the non-inducibility of the electrophysiological study (EPS). Since twelve-lead electrocardiograms (ECG) of the clinical ventricular tachycardia (VT) are also often not available, therefore stored implantable cardioverter-defibrillator (ICD) electrograms (EGMs) of the clinical VT are often the only documentation. The pace mapping matching to the stored ICD-EGM template of the clinical VT can help to identify the VT exit site. Automatic objective computing of similarity scores between EGMs is impossible because ICD programmer devices do not have any interface allowing the export of digital EGMs. Therefore, images can only be accessed for similarity by subjective eyeballing. The MatcherNet Siamese neural network takes a pair of EGM images and predicts their similarity. Purpose This study aimed to assess the feasibility of the automatic ICD-EGMs matching by MatcherNet neural network for pace mapping of VT/premature ventricular contraction (PVC) exit site. Methods Consecutive patients undergoing VT ablation or ablation of ventricular fibrillation, triggered by PVC were included in the study, if the clinical VT/PVC was not inducible during EPS but ICD-EGMs of clinical VT/PVC were stored in the device. Electro-anatomical mapping was performed to reveal substrates (low-voltage areas, abnormal potentials, DEEP-potentials, conduction crowding). Subsequently, the low-output pacing from various locations tagged on the 3D map of LV was performed, and the paced ICD-EGM images were stored from the ICD programmer device for offline analysis and calculation of the similarity. RF ablation was conducted based on the substrate map findings, including the area of the most remarkable similarity between paced ICD-EGMs and clinical ICD-EGM templates assessed by eyeballing. The ICD-EGMs similarity scores (Manhattan similarity and Pearson correlation) were predicted by MatcherNet for each pacing site offline and transferred to the 3D map for the assessment of similarity distribution (Figure 1). Results We included 7 patients with VA episodes registered and stored by their ICD. The clinical characteristics are presented in Table1. In all patients, we were able to find the sites of highest ICD-EGM similarity to the clinical template with gradual decrementing of the similarity score at the increasingly distant pacing areas. The site of the highest similarity was collocated with VT substrate and ablation areas in all patients. Abrupt change of the similarity score at the adjacent pacing sites was detected in the 2 cases, indicating the possible protected VT isthmus. After ablation procedure only one patient with DCM experienced VA recurrence. Conclusion This technology opens new possibilities for the utilization of ICD-EGMs during the pace mapping of ventricular tachycardia, especially in the cases of non-inducibility during electrophysiological study.Figure 1Table 1

PERCUTANEOUS LEFT STELLATE GANGLION BLOCK TO INCREASE VENTRICULAR FIBRILLATION THRESHOLD AND DEFIBRILLATION SUCCESS RATE IN ACUTE FULMINANT MYOCARDITIS WITH ELECTRICAL STORM

Abstract Introduction Acute fulminant myocarditis represents a predisposing substrate for life–threatening ventricular arrhythmias (VAs). Percutaneous left stellate ganglion block (PLSGB) usage has been reported for the prevention of recurrent VAs, but clinical data on its acute effect on ongoing ventricular fibrillation (VF) are missing. Case A 57–years–old man suffering gastroenteritis and fever in the past week presented in the ED with typical chest pain. ECG depicted infero–lateral ST–segment elevation, cardiac ultrasound showed a mildly reduced LVEF and coronary angiography ruled out coronary lesions. In the following hours the patient developed frequent premature ventricular complexes with R on T phenomenon triggering short coupled torsade de pointes with rapid degeneration into VF. VAs episodes, initially responsive to single DC shock, kept recurring despite intravenous (iv) amiodarone, iv lidocaine and iv correction of potassium and magnesium. The patient was therefore treated with deep sedation, intubation and ECMO VA placement; still, he reached a status of persistently ongoing VF, refractory even to DC shocks (n=20). Therefore, ultrasound–guided PLSGB using a local bolus of lidocaine 150 mg + ropivacaine 50 mg was performed. After 5 minutes, a single DC shock was delivered, effective in achieving a stable sinus rhythm at 35 bpm with no more recurrences. Despite electrical stabilization, the patient developed a severe cardiogenic shock due to bradycardia and severe biventricular disfunction, treated with vasopressin and dobutamine. In the next 48 hours we observed a significant improvement, resumption of biventricular contractility and absence of VAs recurrences, so the patient was slowly weaned off ECMO and vasopressors. Immunological tests showed Enterovirus IgM positivity, while endomyocardial biopsy was negative for inflammatory infiltrates in the analyzed sections. Cardiac MRI (performed 10 days after onset) showed edema and non–ischemic LGE in the antero–lateral and infero–lateral basal subepicardial regions of the left ventricle, LVEF was 55%. After 15 days from admission, despite ongoing amiodarone and bisoprolol, the patient developed a run of monomorphic VA of 30 beats at 170 bpm, therefore he underwent sICD implantation. Conclusion PLSGB played a key role for the acute management of refractory VF unresponsive to DC shocks, allowing for acute stabilization. More clinical data are needed on acute neuromodulation for electrical storm.

ARRHYTHMOGENIC RIGHT VENTRICULAR CARDIOMYOPATHY AND CARDIAC SARCOIDOSIS: THE GREY ZONE

Abstract Cardiac sarcoidosis (CS) is a rare multisystem disorder characterized by granulomatous infiltration of the myocardium, whose clinical manifestations can be extremely heterogeneus. We report the case of a 47–year–old man with a previous diagnosis of arrhythmogenic right ventricular cardiomyopathy (ARVD). In history he had a marked arrhythmic pattern with multiple episodes of sustained ventricular arrhythmias, biventricular disfunction (LVEF 37%, RVEF 32%) and extensive biventricular transmural late–gadolinium enhancement (greater than 50%) at cardiac RMN. At EKG epsilon wave mainly seen in precordial leads. In November 2022 he was implanted with bicameral defibrillator and in March 2023 he underwent ablation procedure for ventricular tachycardia with RF with endo–epicardial approach. In May 2023 he arrived at our Centre for acute decompensated heart failure. At restored hemodynamic stability, screening for the possible inclusion in transplant list was started. Right heart catheterization (RHC) showed low cardiac index with no pulmonary hypertension. Chest CT unexpectedly showed the presence of multiple micronodules with perilymphatic distribution with confluent appearance compatible with pulmonary sarcoidosis. In consideration of this result, the transplant program was temporarily postponed and investigations for possible cardiac involvement of an inflammatory nature were started. 18F–FDG PET–CT showed pulmonary, splenic, lymphonodal and especially cardiac uptake in the mid–distal segment of the lateral wall of the left ventricle and in the inferior–apical site suspicious for inflammatory pathology. Unfortunately, both lymphonodal and cardiac biopsies were inconclusive because of insufficient material. Nevertheless, the clinical scenario satisfied the Japanese criteria for possible CS; therefore, treatment with prednisone 1 mg/kg was started and a 18F–FDG PET–CT was planned after 3 months of steroid therapy. CS can disguise as a phenocopy of arrhythmogenic right ventricular cardiomyopathy because of several common characteristics, especially arrhythmic presentation. Due to these similarities, a careful overall evaluation of each patient with ARVD is mandatory as several transplant centers have reported cases of CS in explanted heart with a pretransplant misdiagnosis of ARVD or dilated cardiomiopathy. Performing a chest CT in all ARVD patients as part of transplant screening may be considered.

Electrical Storm/Refractory Ventricular Tachycardia.

This simulation case was created for emergency medicine (EM) residents at all levels of training. Cardiac electrical storm (ES) is commonly defined as three or more episodes of sustained ventricular tachycardia, ventricular fibrillation, or three shocks from an implantable defibrillator within a 24 hour period.1 This can occur in up to 30-40% of patients with implantable defibrillators; however, it may also present in a wide variety of patients, including those with structural heart disease, myocardial infarction, electrolyte disturbances, and channelopathies.2,3 With each subsequent episode of ventricular arrhythmia, the arrhythmogenic potential of the heart may increase secondary to increased intracellular calcium dysregulation, myocardial injury, and increased endogenous release of catecholamines. The increased pain and catecholamine release from cardioversion/defibrillation and exogenous epinephrine during cardiac arrest further exacerbates ES.2 This carries a significant mortality risk of up to 12% in the first 48 hours.3This case involves a basic knowledge of the Advanced Cardiac Life Support (ACLS) for ventricular tachycardia, both with and without a pulse, and the application of Sgarbossa criteria in a patient with an ST elevation myocardial infarction (STEMI) which makes it ideal for the PGY-1. However, the case quickly becomes refractory to the basic management prescribed in ACLS, requiring trouble shooting and quick thinking about deeper pathophysiology, a skill that is crucial for all emergency medicine physicians. There are multiple ways to troubleshoot this case, making for a good variety of discussion and recent literature review on the complexities of a relatively common arrhythmia, ventricular tachycardia. By the end of this simulation, learners should be able to: 1) recognize unstable ventricular tachycardia and initiate ACLS protocol, 2) practice dynamic decision making by switching between various ACLS algorithms, 3) create a thoughtful approach for further management of refractory ventricular tachycardia, 4) interpret electrocardiogram (ECG) with ST-segment elevation (STE) and left bundle branch block (LBBB), 5) appropriately disposition the patient and provide care after return of spontaneous circulation (ROSC), 6) navigate a difficult conversation with the patient's husband when she reveals that the patient's wishes were to not be resuscitated. This simulation was performed using high-fidelity simulation followed by an immediate debriefing with nine learners who directly participated in the SIM and twenty-three residents, who were online observers via Zoom. This case was done during our conference day, and there were a total of approximately forty total learners comprised of medical students, PGY-1, PGY-2 and PGY-3 residents. There were several medical students who also observed via Zoom but were not surveyed, and the survey was sent to 32 learners. The case was run three separate times with each session consisting of three-four learners at the same level of training, with other learners in the same level of training observing via Zoom™ video platform. Since we can only have a team of three-four learners participate per group during simulation, the rest of the learners were observing the case and the debrief. There was one simulation instructor and one technician. We sent an online survey to all the participants and the observers after the debrief via surveymonkey.com. The survey collected responses to the following statements: (1) the case was believable, (2) the case had right amount of complexity, (3) the case helped in improving medical knowledge and patient care, (4) the simulation environment gave me a real-life experience and, (5) the debriefing session after simulation helped improve my knowledge. Likert scale was used to collect the responses. A total of thirteen participants responded to the survey. One hundred percent of them either strongly agreed or agreed that the case was believable and that it helped in improving medical knowledge and patient care. Fifty-four percent strongly agreed, 38 percent agreed, and eight percent were neutral about the case having the right amount of complexity. Thirty one percent strongly agreed, 61 percent agreed, and eight percent were neutral about the case giving them real-life experience. All of them agreed that the debriefing session helped them improve their knowledge. The high-fidelity simulation case was helpful with educating learners with ventricular tachycardia and fibrillation. Learners learned how to switch between various ACLS algorithms and how to manage a patient with refractory ventricular fibrillation. Learners enforced their knowledge in how to communicate with patient's family members when the patient does not want resuscitation. Stable ventricular tachycardia, unstable ventricular tachycardia, refractory ventricular tachycardia, electrical storm, STEMI equivalents, medical simulation.

Management of patients with an electrical storm or clustered ventricular arrhythmias: a clinical consensus statement of the European Heart Rhythm Association of the ESC-endorsed by the Asia-Pacific Heart Rhythm Society, Heart Rhythm Society, and Latin-American Heart Rhythm Society.

Electrical storm (ES) is a state of electrical instability, manifesting as recurrent ventricular arrhythmias (VAs) over a short period of time (three or more episodes of sustained VA within 24 h, separated by at least 5 min, requiring termination by an intervention). The clinical presentation can vary, but ES is usually a cardiac emergency. Electrical storm mainly affects patients with structural or primary electrical heart disease, often with an implantable cardioverter-defibrillator (ICD). Management of ES requires a multi-faceted approach and the involvement of multi-disciplinary teams, but despite advanced treatment and often invasive procedures, it is associated with high morbidity and mortality. With an ageing population, longer survival of heart failure patients, and an increasing number of patients with ICD, the incidence of ES is expected to increase. This European Heart Rhythm Association clinical consensus statement focuses on pathophysiology, clinical presentation, diagnostic evaluation, and acute and long-term management of patients presenting with ES or clustered VA.

Divergent electrophysiologic action of dapagliflozin and empagliflozin on ventricular and atrial tachyarrhythmias in isolated rabbit hearts.

The use of SGLT-2 inhibitors has revolutionized heart failure therapy. Evidence suggests a reduced incidence of ventricular and atrial arrhythmias in patients with dapagliflozin or empagliflozin treatment. It is unclear to what extent the reduced arrhythmia burden is due to direct effects of the SGLT2 inhibitors or is solely a marker of improved cardiac function. One hundred five rabbit hearts were allocated to eight groups and retrogradely perfused, employing a Langendorff setup. Action potential duration at 90% of repolarization (APD90), QT intervals, effective refractory periods, conduction velocity, and dispersion of repolarization were obtained with monophasic action potential catheters. A model for tachyarrhythmias was established with the IKr blocker erythromycin for QT prolongation associated proarrhythmia as well as the potassium channel opener pinacidil for a short-QT model. An atrial fibrillation (AF) model was created with isoproterenol and acetylcholine. With increasing concentrations of both SGLT2 inhibitors, reductions in QT intervals and APD90 were observed, accompanied by a slight increase in ventricular arrhythmia episodes. During drug-induced proarrhythmia, empagliflozin succeeded in decreasing QT intervals, APD90, and VT burden whereas dapagliflozin demonstrated no significant effects. In the presence of pinacidil induced arrhythmogenicity, neither SGLT2 inhibitor had a significant impact on cardiac electrophysiology. In the AF setting, perfusion with dapagliflozin showed significant suppression of AF in the course of restitution of electrophysiological parameters whereas empagliflozin showed no significant effect on atrial fibrillation incidence. In this model, empagliflozin and dapagliflozin demonstrated opposite antiarrhythmic properties. Empagliflozin reduced ventricular tachyarrhythmias whereas dapagliflozin showed effective suppression of atrial arrhythmias.

Clinical and Laboratory Predictors of Long-Term Outcomes after Catheter Ablation for a Ventricular Electrical Storm.

Ventricular electrical storm (VES) is characterized by the occurrence of multiple episodes of sustained ventricular arrhythmias (VA) over a short period of time. Radiofrequency ablation (RFA) has been reported as an effective treatment in patients with ventricular tachycardia (VT). The aim of the present study was to indicate the short-term and long-term predictors of recurrent VA after RFA was performed due to VES. A retrospective, single-centre study included patients, who had undergone RFA due to VT between 2012 and 2021. In terms of the short-term (at the end of RFA) effectiveness of RFA, the following scenarios were distinguished: complete success: inability to induce any VT; partial success: absence of clinical VT; failure: inducible clinical VT. In terms of the long-term (12 months) effectiveness of RFA, the following scenarios were distinguished: effective ablation: no recurrence of any VT; partially successful ablation: VT recurrence; ineffective ablation: VES recurrence. The study included 62 patients. Complete short-term RFA success was obtained in 77.4% of patients. The estimated cumulative VT-free survival and VES-free survival were, respectively, 28% and 33% at the 12-month follow-up. Ischemic cardiomyopathy and complete short-term RFA success were predictors of long-term RFA efficacy. Neutrophil to lymphocyte ratio (NLR) and GFR <60 mL/min/1.73 m2 were associated with VES recurrence. NLR ≥2.95 predicted VT and/or VES recurrence with a sensitivity of 66.7% and specificity of 72.2%. Ischemic cardiomyopathy and short-term complete success of RFA were predictors of no VES recurrence during the 12-month follow-up, while NLR and GFR <60 ml/min/1.73 m2 were associated with VES relapse.

Catheter Ablation for Ventricular Tachycardia in Patients With Desmoplakin Cardiomyopathy

BackgroundDesmoplakin (DSP) pathogenic/likely pathogenic (P/LP) variants are associated with malignant phenotypes of arrhythmogenic cardiomyopathy (DSP-ACM). Reports of outcomes after ventricular tachycardia (VT) ablation in DSP-ACM are scarce. ObjectivesIn this study, the authors sought to report on long-term outcomes of VT ablation in DSP-ACM. MethodsPatients with P/LP DSP variants at 9 institutions undergoing VT ablation were included. Demographic, clinical, and instrumental data as well as all ventricular arrhythmia (VA) events were collected. Sustained VAs after the index procedure were the primary outcome. A per-patient before and after ablation comparison of rates of VA episodes per year was performed as well. ResultsTwenty-four DSP-ACM patients (39.3 ± 12.1 years of age, 62.5% male, median 6,116 [Q1-Q3: 3,362-7,760] premature ventricular complexes [PVCs] per 24 hours, median 4 [Q1-Q3: 2-11] previous VA episodes per patient at ablation) were included. Index procedure was most commonly endocardial/epicardial (19/24) The endocardium of the right ventricle (RV), the left ventricle (LV), or both ventricles were mapped in 8 (33.3%), 9 (37.5%), and 7 (29.2%) cases, respectively. Low voltage potentials were found in 10 of 15 patients in the RV and 11 of 16 in the LV. Endocardial ablation was performed in 18 patients (75.0%). Epicardial mapping in 19 patients (79.2%) identified low voltage potentials in 17, and 16 received epicardial ablation. Over the following 2.9 years (Q1-Q3: 1.8-5.5 years), 13 patients (54.2%) experienced VA recurrences. A significant reduction in per-patient event/year before and after ablation was observed (1.4 [Q1-Q3: 0.5-2.4] to 0.1 [Q1-Q3: 0.0-0.4]; P = 0.009). Two patients needed heart transplantation, and 4 died (3 of heart failure and 1 noncardiac death). ConclusionsVT ablation in DSP-ACM is effective in reducing the VA burden of the disease, but recurrences are common. Most VT circuits are epicardial, with both LV and RV low voltage abnormalities. Heart failure complicates clinical course and is an important cause of mortality.

Early Ventricular Arrhythmias after Left Ventricular Assist Device Implantation

BackgroundWhile sustained ventricular arrhythmias are a common complication following durable left ventricular assist device (LVAD) implantation, the incidence, risk factors, and prognostic implications of early postoperative ventricular arrhythmias (EVAs) in contemporary LVAD patients are poorly understood. MethodsA single-center retrospective analysis was performed of patients who underwent LVAD implantation from 10/1/2006-10/1/2022. EVA was defined as an episode of sustained ventricular arrhythmia identified ≤30 days after LVAD implantation. ResultsA total of 789 patients underwent LVAD implantation (age: mean 62.9 years ± 0.5, HeartMate 3: 41.4%, destination therapy: 43.3%). EVAs occurred in 100 (12.7%) patients. A history of ESRD (OR 5.6, CI 1.45-21.70), preoperative electrical storm (OR 2.82, CI 1.11-7.16) and appropriate ICD therapy prior to implantation (OR 2.8, CI 1.26-6.19) are independently associated with EVAs. EVA was associated with decreased 30-day survival (HR 3.02; 1.1-8.3 95% CI; p = 0.032). There was no difference in transplant-free survival time between patients with and without EVAs (HR 0.82; 0.5-1.4 95% CI; p = 0.454). ConclusionEVAs are common after durable LVAD implantation and are associated with increased risk of 30-day mortality.

Time for a new destination: foregoing surgical sympathectomy after successful stellate ganglion block in patients with refractory ventricular tachycardia

Abstract Background Electrical storm (ES) is defined as &amp;gt;3 episodes of sustained ventricular arrhythmias in 24 hours and is associated with increased mortality. ES portends a poor prognosis with limited effective treatment options. Stellate ganglion block (STGB) can be used in patients with ES for temporary control of VT. When STGB is successful, patients can be referred for surgical sympathectomy for longer term management. We postulated that STGB can be used as a bridge to other treatments for refractory VT. Purpose To evaluate the efficacy of STGB as a bridge to interventions other than surgical sympathectomy in patients with refractory VT. Additionally, we assessed STGB as an adjunctive therapy to medical optimization when the cause for ES is temporary (e.g., QT prolonging medications, acute ischemia) foregoing the need for long term interventions. Methods This is a single center retrospective study. We enrolled 12 consecutive patients admitted from July 2018 to September 2022 for ES that received a STGB. The primary clinical outcome was cessation of VT for 24 hours beginning 1 hour after STGB was performed. Secondary clinical outcome of the study was freedom from VT until discharge after STGB. Primary safety outcomes were major procedural complications or death within 48 hours after STGB. Results Sixty-seven percent of the patients were male, with a mean age of 58 years and an average left ventricular ejection fraction of 32%. Two-thirds of the patients had ischemic VT of which half were status post CABG and the other half were status post PCI. In the first 24 hours after STGB, 91% of patients were without recurrent VT. Fifty percent of patients did not have recurrent VT from 24 hours after SGB was performed until discharge. Three patients were referred for catheter ablation. No patients received surgical sympathectomy. There were no major complications or deaths within 48 hours of STGB. Conclusion STGB is a safe and effective procedure that can be utilized as a bridge to VT interventions other than surgical sympathectomy. For patients with ES, STGB is also effective at temporarily suppressing VT allowing time for medical optimization and the withdrawal of provoking agents which perpetuate ES. Further research is necessary to determine optimal timing and patient selection for STGB when used as a bridge for alternative VT therapies.Clinical Impact of VT after STGBElectrical Storm Characteristics

Mitral annulus disjunction: a detailed magnetic resonance study of phenotype and clinical significance

Abstract Background The clinical significance and arrhythmogenic propensity of mitral annulus disjunction (MAD) are not well established. Our aim was to characterize MAD in all-comers, analyzing the mitral valve apparatus in detail, scar burden and clinical outcomes. Methods Single-center retrospective analysis of all consecutive patients with MAD described by cardiovascular magnetic resonance (CMR) between 2010-2022. Medical history, imaging and arrhythmia data were analysed. Cardiovascular mortality was assessed. MAD was defined as a separation ≥2mm between the left ventricular myocardium and the mitral annulus. Presence and pattern of left ventricle (LV) late gadolinium enhancement (LGE) was assessed. Scar in the papillary muscles and areas adjacent to the MAD was identified as MAD-related. Ventricular arrhythmias (VA) were grouped into non-sustained (ectopies&amp;gt;10%/24h or ventricular tachycardia) or sustained. Results Out of 341 patients who were initially identified as possibly having MAD, MAD was confirmed in 222. Mean age was 49.2±19.3 years, 126 were male (56.8%). Mean longitudinal MAD extent was 5±2.6mm, while circumferential involvement of a single segment (60º) was most commonly seen (n=99, 44.6%). The inferior wall was the affected segment (n=116, 52.2%) with more extensive MAD, followed by the inferolateral wall (n=71, 32%). Mitral valve (MV) annulus expanded during systole in patients with MAD ≥6mm, while annular contraction occurred in those with MAD &amp;lt;6mm. Annular expansion was associated with MV prolapse (p=0.003), billowing (p=0.018) and curling (p&amp;lt;0.001). LV LGE was present in 82 patients (36.9%), with 23 patients (10.4%) showing MAD-related LGE, but no association with disease extent (MAD length or circumferential involvement). Median follow-up time was 1392 (872-1922) days. No episode of sustained VA was observed. In univariable analysis non-sustained VA was significantly more prevalent in patients with MAD ≥6mm (p=0.002), although this tendency faded after multivariate analysis (p=0.053). The presence of non-sustained VA was associated with global LV LGE (p=0.005), but not MAD-related LGE in isolation - Table 1. Three patients died of cardiovascular causes (1.4%), but none had extensive MAD or MAD-related LGE. None died of sudden cardiac arrest. To the best of our knowledge, this is the biggest dataset of MAD patients that simultaneously analysis phenotype, including LGE, and clinical outcomes. Conclusion Mitral valve dysfunction (prolapse/billowing) is linked to MAD severity. Scar is common, not related to the extent of MAD, but a predictor of VAs independently of its location. The risk of sustained ventricular arrhythmias and cardiovascular death appears to be low in this all-comers population.Table 1

Arrhythmogenic cardiomyopathy phenotype associated with the pathogenic founder variant c.1211dup in PKP2

Abstract Background Arrhythmogenic cardiomyopathy results in life-threatening ventricular arrhythmia and heart failure. Phenotypic features vary according to genetic aetiology. Genotype-phenotype research is therefore crucial for patient counselling and treatment decisions such as implantable cardioverter defibrillator therapy. By collecting data from patient records we characterized the clinical phenotype associated with variant c.1211dup (p.Val406Serfs*4) in the plakophilin-2 gene (PKP2), common in the Dutch population. Purpose We aimed to investigate the incidence of ventricular arrhythmia and heart failure in families carrying the PKP2 c.1211dup variant. Furthermore, we aimed to determine the founder status of this variant, and compare phenotype severity with other truncating PKP2 variants. Methods Clinical data were collected retrospectively from medical records of 106 PKP2 c.1211dup heterozygous carriers (&amp;gt;85% of known carriers in The Netherlands) in a Castor EDC database. Using occurrence of ventricular arrhythmia and heart failure, event-free survival was compared between males and females, and probands and family members, using log-rank tests. Using data from a central curated arrhythmogenic cardiomyopathy database, c.1211dup was compared to three other truncating PKP2 variants (c.235C&amp;gt;T (p.Arg79*), c.397C&amp;gt;T (p.Gln133*) and c.2489+1G&amp;gt;A (p.?)) on ventricular arrhythmia-free survival by a Cox proportional hazards model, corrected for sex and proband status. Results Forty-seven carriers (44%) were diagnosed with arrhythmogenic cardiomyopathy at 41 years on average. As shown in figure 1, 29 participants (27%) experienced episodes of ventricular arrhythmia and 12 (11%) developed heart failure, with male carriers showing significantly higher risks than females on both endpoints (p&amp;lt;0.05). Based on available magnetic resonance imagery and echocardiographic data, 46% of carriers showed either right ventricular dilatation and/or dysfunction, and a substantial minority of 37% showed some form of left ventricular involvement. Both geographical distribution of carriers (figure 2) and haplotype analysis suggested PKP2 c.1211dup to be a founder variant originating from the South-Western coast of the Netherlands. Finally, a Cox proportional hazards model suggested significant differences in ventricular arrhythmia-free survival between four PKP2 truncating founder variants, including c.1211dup. Conclusions The PKP2 c.1211dup variant is a Dutch founder variant associated with a typical right ventricular-dominant arrhythmogenic cardiomyopathy phenotype, but also notable left ventricular involvement. Males were most susceptible to the frequent ventricular arrhythmia, and less frequent heart failure was observed in general. Finally, c.1211dup possibly leads to a more severe phenotype than other Dutch PKP2 founder variants.Phenotype onset stratified by sexGeographic distribution carriers

Abstract 13790: Efficacy of Stellate Ganglion Block for Refractory Ventricular Arrhythmias: An Updated Systematic Review

Background: Stellate ganglion block (SGB) has emerged as an alternative approach to refractory ventricular arrhythmias (VAs). However, data on the outcome of SGB for refractory VAs are limited. Objective: This study aimed to assess the in-hospital efficacy of SGB in refractory VAs. Method: A systematic search was performed in MEDLINE and EMBASE according to the PRISMA guidelines from July 2017 to October 2022. Studies reporting the characteristics of in-hospital VAs before and after the SGB were included. Studies that had missing outcomes were excluded. Results: Of 515 publications reviewed, 162 patients (60.6 ± 13.6 years of age, 81.5% male) were included across 27 studies. Amongst, 103 patients (63.6%) had ischemic cardiomyopathy, and the mean ejection fraction was 29.8 ± 12.7%. Prior to the SGB procedure, 100 patients (61.7%) required two or more anti-arrhythmic medications control. Following SGB, there was a significant 92% reduction of VAs episodes from 13.9 ± 18.5 to 0.9 ± 2.1 (p&lt;0.01) during the hospitalization (31±35 days). Of the reported patients, 46.5% remained free of VAs, and 53.5% had recurrences before discharge. Among 61 patients who required additional neuromodulation after SGB in the same hospitalization, 32 patients (52.5%) received repeated SGB, 15 patients (24.6%) underwent surgical sympathectomy, and 14 patients (23%) underwent catheter ablation. Of the reported patients, 75.4% of patients survived throughout the hospital course. Conclusion: SGB significantly reduced VAs episodes in patients with refractory VAs during hospitalization. More than three-quarters of the patients survived following the SGB for refractory VAs. This highlights the potential effective role of SGB in managing refractory VAs. Figure Change in Ventricular Arrhythmias Burden after Stellate Ganglion Block

Efficacy and safety of in-hospital treatment of Covid-19 infection with low-dose hydroxychloroquine and azithromycin in hospitalized patients: A retrospective controlled cohort study

ObjectivesIn this study we evaluate the efficacy and safety of a treatment protocol with standard dose of hydroxychloroquine plus azithromycin in patients hospitalized with COVID-19 infection. MethodsWe conducted a retrospective analysis to compare the 28-day mortality rate in 352 patients treated with hydroxychloroquine with or without azithromycin (HCQ-group) in our hospital with a contemporary control group of 3533 patients receiving standard of care from the Belgian Collaborative Group on COVID-19 Hospital Surveillance. ResultsAll patients who received at least one dose of treatment were included in the analysis. A statistically significant reduction in crude mortality rate at 28 days was observed in the HCQ-group compared to standard of care (16.8% vs 25.9%,p ​= ​0.001).Patients in the treatment group were on average younger (69,7 vs73,1 years, p ​= ​0,0002), were less likely to smoke or to have malignancy and more likely to be male. Patients in the treatment group were more likely to be obese, immunocompromised or to have arterial hypertension, liver disease and lung disease.After adjustment for these variables the OR for mortality was 0.635 (95%CI 0.464–0.875). Patients who did not receive HCQ had a 57% higher risk of mortality. A survival benefit in the treatment group was consistent across all age groups. 13 patients discontinued treatment due to side effects (4 with QTc-prolongation>60msec (1.1%) and 9 because of gastro-intestinal symptoms (2.55%)). No episodes of ventricular arrhythmia or torsade de pointes were recorded during treatment. ConclusionTreatment of COVID-19 using a combination of hydroxychloroquine plus azithromycin was safe and was associated with a statistically significant mortality benefit in the treatment of COVID-19 infection in hospitalized patients. Our findings do not support the current negative recommendations regarding this treatment.

Electrical storm management in the cardiac care unit

Electrical storm (ES) is characterized by at least three separate episodes of ventricular arrhythmia (VA) over 24 h that require treatment or an incessant VA lasting >12 h. The incidence is higher in patients with implantable cardioverter-defibrillators (ICDs) in secondary prevention and the main manifestation is monomorphic VA. ES onset represents a major event in the history of patients with cardiomyopathies that significantly worsens prognosis. The management of ES is complex and requires a multidisciplinary approach including a comprehensive clinical assessment, resuscitation and sedation management skills, ICD reprogramming, ablation, and neuromodulation procedures. ES early recognition and prompt treatment initiation increase the chances of therapeutic success. Each one of these aspects will be properly discussed in the present decalogue. Notably, ES management remains a challenge, with only limited available evidence from small retrospective series and a substantial lack/limited number of randomized or prospective trials. The spectrum of available antiarrhythmic drugs is limited, as well as their efficacy. The future hope is that larger prospective studies will be able to answer important questions, concerning the most effective pharmacologic strategies, the timing for the invasive treatment, the indications for acute neuromodulation strategies and for the circulatory support tools.

A Common East Asian aldehyde dehydrogenase 2*2 variant promotes ventricular arrhythmia with chronic light-to-moderate alcohol use in mice

Chronic heavy alcohol use is associated with lethal arrhythmias. Whether common East Asian-specific aldehyde dehydrogenase deficiency (ALDH2*2) contributes to arrhythmogenesis caused by low level alcohol use remains unclear. Here we show 59 habitual alcohol users carrying ALDH2 rs671 have longer QT interval (corrected) and higher ventricular tachyarrhythmia events compared with 137 ALDH2 wild-type (Wt) habitual alcohol users and 57 alcohol non-users. Notably, we observe QT prolongation and a higher risk of premature ventricular contractions among human ALDH2 variants showing habitual light-to-moderate alcohol consumption. We recapitulate a human electrophysiological QT prolongation phenotype using a mouse ALDH2*2 knock-in (KI) model treated with 4% ethanol, which shows markedly reduced total amount of connexin43 albeit increased lateralization accompanied by markedly downregulated sarcolemmal Nav1.5, Kv1.4 and Kv4.2 expressions compared to EtOH-treated Wt mice. Whole-cell patch-clamps reveal a more pronounced action potential prolongation in EtOH-treated ALDH2*2 KI mice. By programmed electrical stimulation, rotors are only provokable in EtOH-treated ALDH2*2 KI mice along with higher number and duration of ventricular arrhythmia episodes. The present research helps formulate safe alcohol drinking guideline for ALDH2 deficient population and develop novel protective agents for these subjects.

Survival, ventricular arrhythmia, and implantable cardioverter-defibrillator usefulness in toxic cardiomyopathy due to substance abuse.

Toxic dilated cardiomyopathy (T-DCM) due to substance abuse is now recognized as a potential cause of severe left ventricular dysfunction. The burden of ventricular arrhythmias (VA) and the role of a prophylactic implantable cardioverter-defibrillator (ICD) are not well documented in this population. We aim to assess the usefulness of ICD implantation in a T-DCM cohort. Patients younger than 65 years with a left ventricular ejection fraction (LVEF)<35% followed at a tertiary center heart failure (HF) clinic between January 2003 and August 2019 were screened for inclusion. The diagnosis of T-DCM was confirmed after excluding other etiologies, and substance abuse was established according to the DSM-5 criteria. The composite primary endpoints were arrhythmic syncope, sudden cardiac death (SCD), or death of unknown cause. The secondary endpoints were the occurrence of sustained VA and/or appropriate therapies in ICD carriers. Thirty-eight patients were identified, and an ICD was implanted in 19 (50%) of these patients, only one for secondary prevention. The primary outcome was similar between the two groups (ICD vs. non-ICD; p=1.00). After a mean follow-up of 33±36 months, only two VA episodes were reported in the ICD group. Three patients received inappropriate ICD therapies. One ICD implantation was complicated with cardiac tamponade. Twenty-three patients (61%) had an LVEF ≥35% at 12 months. VA are infrequent in the T-DCM population. The prophylactic ICD benefit was not observed in our cohort. The ideal timing for potential prophylactic ICD implantation in this population needs further studies.

Effects of CRT on atrial and ventricular arrhythmias in patients with HF

Abstract Funding Acknowledgements Type of funding sources: None. Introduction Cardiac resynchronization therapy (CRT) is an accepted treatment for patients with heart failure (HF). Cardiac arrhythmias present a significant and complex issue in this patient group. Evidence exploring the influence of CRT on cardiac arrhythmias rate variations is limited. Purpose Our research investigates the effectiveness of CRT in the treatment of existing and newly diagnosed atrial and ventricular arrhythmias, and impact of epicardial lead position on these arrhythmias rate variations, as well as on the CRT response. Methods This single-center, prospective, observational study included 75 consecutive patients admitted for CRT implantation over a 12-month period. All included patients had episodes of atrial and/or ventricular arrhythmias, diagnosed by 12-lead ECG or 24-hour Holter monitoring. Pre-procedural demographic characteristics were collected for all patients, including ECG records, NYHA functional class, echocardiographic assessment of left ventricular ejection function and questionnaire for quality-of-life. During device follow up atrial and ventricular arrhythmias appearance was monitored. Additional assessment of echocardiographic parameters, NYHA - functional class, quality of life and rate of major cardiovascular complications and rehospitalizations was performed. Results The mean age of the patients was 62.4 ± 10.3 years, with 74.6% male and 25.3% females. 72% had a non-ischemic HF etiology. Pre-procedural paroxysmal AF was present in 34.7%, persistent AF in 36%, PVCs in 32%, NSVT 16%, and VT in 18,7% patients. 55% of the included patients were responders to CRT. Our results showed decrease in rate of all ventricular arrhythmias, with significant reduction in the percentage of VT (p=0.003), regardless of CRT response. Significant reduction of PVCs and NSVT rate (p=0.012 &amp; p=0.024) was found in the responder group of patients. Regarding AF, our results showed a decrease in the number of AF events in both patient groups, however this was most visible in the responder patients with paroxysmal AF (p=0.057). In CRT responders, left ventricular pacing lead was most commonly located in a lateral branch vein of the CS with middle and mid/lateral position. In terms of quality of life and general condition of the patients, we noticed a significant improvement in the NYHA - functional class (p &amp;lt;0.001), as well as in both parts of the quality-of-life assessment questionnaire (p=0.0135, p&amp;lt;0.001). Conclusion CRT is an effective treatment for atrial and ventricular arrhythmias in HF patients, especially in responders to this therapy. LV epicardial lead position proved to be very important influence in the process of LV reverse remodeling, which is in direct correlation of the CRT responders and its effectiveness in reducing the rate of cardiac arrhythmias.