Recurrent Ventricular Arrhythmias Research Articles

FIRST ITALIAN CASE OF TRANSCATHETER TREATMENT OF AORTIC REGURGITATION IN L–VAD PATIENT WITH A DEDICATED DEVICE

Abstract In patients with L–VADs, aortic valve regurgitation is a relatively frequent complication often associated with high mortality. Surgical approaches are extremely complex and often lead to poor outcomes. TAVI can be a feasible solution but it is usually extremely challenging due to the absence of calcification and stenosis. We report the case of a 56–year–old man who underwent LVAD implantation 4years ago as destination therapy for dilated myocardiopathy and chronic multiple myeloma. During the last year, he progressively developed severe pure aortic regurgitation. Last month, he was admitted to our center for heart failure symptoms and recurrent ventricular arrhythmias (VT/VF). The patient was considered at high risk for surgery and evaluated for a transcatheter approach. Due to the absence of calcification and a relatively large annulus, we decided to use the JenaValve Trilogy prosthesis, the only THV CE approved for aortic regurgitation treatment. Unlike other types of THV (self– or balloon expandable), this is specifically designed for AR and does not require significant oversizing to allow correct anchoring. Another advantage in this setting is the possibility of avoiding the reduction of the LVAD flow due to the reduced risk of embolization and the possibility of proceeding to direct implantation without ventricular rapid pacing thanks to the direct anchoring method onto the native aortic leaflets. In this patient, a JenaValve size L bioprosthesis was implanted transfemorally under general anesthesia with an excellent result. The post–operative echocardiography showed a perfectly implanted prosthesis with no intraprosthesis regurgitation and only a mild anterior paravalvular leak with a subsequent improvement of all hemodynamic parameters. In our opinion, when feasible, the JenaValve implant can be a safe and effective therapeutic option in patients with active LVAD devices at high operative risk.

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.

Signal-averaged electrocardiography as a noninvasive tool for evaluating the ventricular substrate in patients with nonischemic cardiomyopathy: reassessment of an old tool.

Signal-averaged electrocardiography (SAECG) provides diagnostic and prognostic information regarding cardiac diseases. However, its value in other nonischemic cardiomyopathies (NICMs) remains unclear. This study aimed to investigate the role of SAECG in patients with NICM. This retrospective study included consecutive patients with NICM who underwent SAECG, biventricular substrate mapping, and ablation for ventricular arrhythmia (VA). Patients with baseline ventricular conduction disturbances were excluded. Patients who fulfilled at least one SAECG criterion were categorized into Group 1, and the other patients were categorized into Group 2. Baseline and ventricular substrate characteristics were compared between the two groups. The study included 58 patients (39 men, mean age 50.4 ± 15.5 years), with 34 and 24 patients in Groups 1 and 2, respectively. Epicardial mapping was performed in eight (23.5%) and six patients (25.0%) in Groups 1 and 2 (p = 0.897), respectively. Patients in Group 1 had a more extensive right ventricular (RV) low-voltage zone (LVZ) and scar area than those in Group 2. Group 1 had a larger epicardial LVZ than Group 2. Epicardial late potentials were more frequent in Group 1 than in Group 2. There were more arrhythmogenic foci within the RV outflow tract in Group 1 than in Group 2. There was no significant difference in long-term VA recurrence. In our NICM population, a positive SAECG was associated with a larger RV endocardial scar, epicardial scar/late potentials, and a higher incidence of arrhythmogenic foci in the RV outflow tract.

Noncomplex ventricular arrhythmia associated with greater freedom from recurrent ectopy at 1 year after mitral repair surgery

ObjectiveThe effect of mitral valve (MV) surgery on the natural history of ventricular arrhythmia (VA) in patients with arrhythmic MV prolapse remains unknown. We sought to evaluate the cumulative incidence of VA at 1 year after surgical mitral repair. MethodsA retrospective review of progressively captured data identified 204 consecutive patients who underwent elective MV repair for significant degenerative mitral regurgitation as a first-time cardiovascular intervention in a quaternary reference center between January 2018 and December 2020. A subset of 62 consecutive patients with diagnosed arrhythmic MV prolapse was further evaluated for recurrent VA after MV repair. ResultsThe median age was 62 years (range, 27-77 years) and 26 of 62 (41.9%) were female. The median time from initial mitral regurgitation/MV prolaspe diagnosis-to-referral was 13.8 years (interquartile range [IQR], 5.4-25) and from VA diagnosis-to-referral was 8 years (IQR, 3-10.6). Using the Lown-Wolf classification, complex VA (Lown grade ≥3) was identified in 36 of 62 patients (58%) at baseline, whereas 8 of 62 (13%) had a cardioverter/defibrillator implanted for primary (4/8) or secondary (4/8) prevention. Left ventricular myocardial scar was confirmed in 23 of 34 (68%) of patients scanned at baseline. The prevailing valve phenotype was bileaflet Barlow (59/62; 95.2%). All patients underwent surgical MV repair by the same team. Surgical repair was stabilized with an annuloplasty prosthesis (median size 36 mm [IQR, 34-38]). Concomitant procedures included tricuspid valve repair (51/62; 82.3%), cryo-maze ± left atrial appendage exclusion (14/62, 23%), and endocardial cryoablation of VA ectopy (4/62; 6.5%). The 30-day and 1-year freedom from recurrent VA were 98.4% and 75.9%, respectively. Absent VA after mitral repair was uniformly observed in patients with minor VA at baseline. Absent VA after mitral repair was uniformly observed in patients with minor VA preoperatively. Complex baseline VA was the strongest predictor of recurrent VA (hazard ratio, 10.8; 95% confidence interval, 1.4-84.2; P = .024), irrespective of myocardial fibrosis. ConclusionsIn a series of 62 consecutive patients operated electively for arrhythmic mitral prolapse, VA remained undetected in 75.9% of patients at 1 year. Freedom from recurrent VA was greater among patients without complex VA preoperatively, whereas baseline Lown grade ≥3 was the strongest independent risk factor for recurrent VA at 1 year. These findings attest to the importance of early recognition and prompt referral of patients with mitral prolapse and progressive VA to specialty interdisciplinary care.

Incidence and Predictors for Recurrence of Ventricular Arrhythmia Presenting During Acute Myocarditis: A Multicenter Study.

Management of acute myocarditis (AM) patients experiencing ventricular arrhythmia (VA) during acute illness is controversial, especially regarding early implantable cardioverter-defibrillator (ICD) implantation. The purpose of this study was to evaluate the prevalence of and find predictors for long-term sustained VA recurrence and overall mortality among AM patients with VA. This was a multicenter retrospective analysis of AM patients (verified by cardiac magnetic resonance imaging or myocardial biopsy) with documented VA during the acute illness ("initial VA"). Patients with history of myocardial infarction, heart failure, or VA were excluded. The study endpoint was a composite of sustained VA and overall mortality during follow-up. The study included 69 AM patients with initial VA: sustained monomorphic ventricular tachycardia (MMVT) (n=25), sustained polymorphic ventricular tachycardia (VT)/ventricular fibrillation (n=13), and nonsustained VT (n=31). Age was 44 ± 13 years, and 23 of 69 (33.3%) were women. During median follow-up of 5.5 years, 27 of 69 (39%) patients reached the composite endpoint including sustained VA (n=24) and death (n=11). Initial MMVT, predischarge left ventricular dysfunction (left ventricular ejection fraction<50%), and anteroseptal delayed enhancement on cardiac magnetic resonance imaging were significantly associated with the composite endpoint. On multivariable analysis, initial MMVT (HR: 5.17; 95%CI: 1.81-14.6; P=0.001) and predischarge LV dysfunction (HR: 4.57; 95%CI: 1.83-11.5; P=0.005) were independently associated with the composite endpoint. Using these 2 predictors, we could delineate subgroups with low (∼4%), medium (∼42%), and high (∼82%) 10-year incidence of composite endpoint. AM patients presenting with VA have high incidence of sustained VA recurrence and mortality posthospitalization. Initial MMVT and predischarge LV dysfunction are independently associated with VA recurrence and mortality. Implantable cardioverter-defibrillator implantation may be considered in such high-risk patients.

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.

Evaluating Catheter Ablation Versus Conventional Management for Ventricular Arrhythmias in Arrhythmogenic Right Ventricular Cardiomyopathy: A Five-Year Retrospective Cohort Study.

Background Arrhythmogenic right ventricular cardiomyopathy (ARVC) is a challenging genetic disorder marked by ventricular arrhythmias and sudden cardiac death, particularly in athletes and young adults. Despite its clinical significance, the relative effectiveness and safety of catheter ablation versus conventional management in ARVC are not fully delineated. Objective This study evaluates the efficacy and safety of catheter ablation compared to conventional management in reducing ventricular arrhythmias and improving patient outcomes over five years in ARVC patients. Methods In a retrospective cohort design at Lady Reading Hospital, Peshawar, we analyzed 120 ARVC patients from January 2018 to December 2023. Patients were divided into two groups: those undergoing catheter ablation and those receiving conventional management. Primary outcomes assessed were recurrence of ventricular arrhythmias, procedural complications, hospitalization duration, and mortality rates. Logistic regression was adjusted for demographics and clinical variables. Results Catheter ablation significantly lowered the recurrence of ventricular arrhythmias (20% vs. 55%, p<0.01) and reduced hospital stay duration (4 ± 2 days vs. 7 ± 3 days, p<0.05). A trend toward reduced five-year mortality was observed in the catheter ablation group (5% vs. 15%, p=0.07). Age, New York Heart Association class, and exercise capacity emerged as significant predictors of outcomes. Conclusions Catheter ablation outperforms conventional management in reducing the recurrence of ventricular arrhythmias and hospitalization in ARVC patients, with a promising trend toward enhanced survival. These findings advocate for personalized management strategies in ARVC, highlighting the necessity for further research to establish the long-term benefits of catheter ablation.

Early Onset Severe Aortic Stenosis Presenting with Recurrent Ventricular and Supraventricular Arrhythmia and Postoperative Stroke in a 44-year-old Man with Uncontrolled Rheumatoid Arthritis

Calcific aortic stenosis is the most common aetiology of aortic stenosis and is mostly seen in older people. Systemic inflammatory diseases, such as rheumatoid arthritis (RA), are rarely associated with aortic stenosis in the literature. Uncontrolled systemic inflammation related to RA may lead to postoperative complications but this is not well documented. The patient in this case report was a 44-year-old man who had been diagnosed with RA that had been poorly controlled. He had a 7-month history of heart failure symptoms attributed to severe calcific aortic stenosis. He underwent surgical aortic valve replacement, but developed an acute cerebrovascular infarct 2 hours after surgery and recurrent unstable ventricular tachycardia on the first postoperative day warranting 15 synchronised cardioversions. RA is a rare antecedent cause of severe calcific aortic stenosis especially in younger people. Such a valvular complication associated with acute ischaemic stroke and ventricular arrhythmia warrants further study to provide optimal medical management, especially for patients with RA and early cardiovascular complications.

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.

Mid-term outcome of catheter ablation of idiopathic non-outflow tract ventricular arrhythmias

BackgroundCatheter ablation is recommended in patients with frequent and symptomatic ventricular arrhythmias (VAs) in an otherwise normal heart. Right or left outflow tract (OT) are the most common origins, and catheter ablation is highly effective with low complication rates. However, outcome of catheter ablation of VAs other than the OT (non-OTVAs) is limited. The aim of this single-center study was to assess the safety and mid-term outcome of catheter ablation for non-OTVAs.Method and ResultsFrom 2013 to 2018, 251 patients who underwent catheter ablation for idiopathic non-OTVAs were enrolled and grouped according to the origins including His-Purkinje system (HPS, n = 108), papillary muscle / moderator band (PM/MB, n = 47), tricuspid annulus (TA, n = 70), and mitral annulus (MA, n = 26), 244 (97.2%) had acute elimination of VAs. The time of VAs recurrence of the single procedure was 1.69 (0.12,9.72) months, with 66% occurring within the first 3 months. The recurrence rate was significantly higher in the PM/MB group than in the TA (p = 0.025) and MA groups (p = 0.023). The single procedure success rate in all patients was 70.1%, in which 66.7%, 59.6%, 80%, and 76.9% were achieved in the HPS, PM/MB, TA, and MA groups, respectively (p = 0.284). After multiple procedures, the total success rate was 76.5% at the follow-up of 4.38 ± 2.42 years. The rate was significantly lower in the PM/MB group than in the TA group (p = 0.035). In subgroup analysis, no significant difference was observed in the recurrence rate of single procedure in patients with different VA origins within the PM/MB (log-rank test, p = 0.546).ConclusionDespite a certain percentage of recurrences observed in the mid-term follow-up, catheter ablation remained feasible and effective for idiopathic non-OTVAs.

Electrophysiological characteristics and ablation of ventricular arrhythmias originating from the intramural basal inferior septum.

The electrocardiographic and electrophysiological characteristics of ventricular arrhythmia (VA) arising from the intramural basal inferior septum (BIS) have not been specifically addressed to date. The aim of the current study was to characterize intramural BIS-VA and distinguish it from those with endocardial origins besides clarifying the anatomical configurations of the pyramidal space. Fifty-five consecutive patients undergoing catheter ablation of VAs from BIS were identified and divided into three groups: the left ventricular (LV)-BIS group (n = 28), right ventricular (RV)-BIS group (n = 8), and intramural group (Intra, n = 19). Compared with the LV-BIS and RV-BIS groups, patients in the Intra group presented with no adequate earliest activation time at the two-sided BIS and epicardial coronary system [right: 7.79 ± 2.38 vs. left: 7.16 ± 2.59 vs. the middle cardiac vein (MCV): 6.26 ± 1.73 ms, P = 0.173] and poor-matched pacing-produced QRS at each site. Under the intracardiac echocardiography view, the pyramidal base was the broadest part of the septum and served as the division of the two-sided BIS. Focal ablation yielded promising acute-term and long-term procedural success in the LV-BIS and RV-BIS groups. But for the Intra group, VAs disappeared only after stepwise ablation successively targeted early preferential exit. After follow-up, three patients in the Intra group had recurrent VA, and all of them were treated well by a redo procedure or drug therapy. Intramural VAs were relatively common in the BIS region in our series. Intra-procedural mapping was important to distinguish the intramural VAs from other VAs by comparing the local activation time and pacing mapping. Procedural success could be achieved by stepwise ablation on the counterpart sides of the BIS and within the MCV.

Recurrent malignant ventricular arrhythmias and paresthesia—a mystery revealed as aconitine poisoning: a case report

BackgroundWe report a case of a clinical challenge lasting for 12 months, with severe and unresolved clinical features involving several medical disciplines.Case presentationA 53-year-old Caucasian male, who had been previously healthy apart from a moderate renal impairment, was hospitalized 12 times during a 1-year period for a recurrent complex of neurological, cardiovascular, and gastrointestinal symptoms and signs, without any apparent etiology. On two occasions, he suffered a cardiac arrest and was successfully resuscitated. Following the first cardiac arrest, a cardiac defibrillator was inserted. During the 12th admission to our hospital, aconitine poisoning was suspected after a comprehensive multidisciplinary evaluation and confirmed by serum and urine analyses. Later, aconitine was also detected in a hair segment, indicating exposure within the symptomatic period. After the diagnosis was made, no further episodes occurred. His cardiac defibrillator was later removed, and he returned to work. A former diagnosis of epilepsy was also abandoned. Criminal intent was suspected, and his wife was sentenced to 11 years in prison for attempted murder. To make standardized assessments of the probability for aconitine poisoning as the cause of the eleven prior admissions, an “aconitine score” was established. The score is based on neurological, cardiovascular, gastrointestinal, and other clinical features reported in the literature. We also make a case for the use of hair analysis to confirm suspected poisoning cases evaluated after the resolution of clinical features.ConclusionThis report illustrates the medical challenge raised by cases of covert poisoning. In patients presenting with symptoms and signs from several organ systems without apparent cause, poisoning should always be suspected. To solve such cases, insight into the effects of specific toxic agents is needed. We present an “aconitine score” that may be useful in cases of suspected aconitine poisoning.

Abstract 16815: Outcomes of Cardiac Sympathetic Denervation via Cautery Ablation for Ventricular Arrhythmia: A Single Center Study

Introduction: Cardiac sympathectomy denervation (CSD) has been demonstrated to reduce ventricular arrhythmia (VA) burden and to improve arrhythmia-free survival. Early evidence for the clinical antiarrhythmic benefits for CSD was established in patients with long-QT syndrome and catecholaminergic polymorphic VT (CPVT). Its benefit has subsequently been shown to extend to other undifferentiated cardiomyopathies. Hypothesis: Literature on CSD for VA has been limited due to a small number of patients. Our retrospective study is to review patients who underwent CSD for VA at our center via cautery ablation. Methods: We identified 9 patients who underwent CSD from 4/2018 to 2/2022. Electronic medical record was reviewed for clinical history and outcomes. Results: Mean age was 52±17 and 5 patients (55.6%) were male. Seven patients (77.8%) had nonischemic cardiomyopathy (NICM) and 2 patients (22.2%) had CPVT. Mean LVEF was 43±19% and 5 patients (55.6%) had heart failure with NYHA class 3±0.7. Five patients (55.6%) underwent CSD in outpatient setting and 4 patients (44.4%) had polymorphic VT. Six patients (66.7%) had prior catheter-based VT ablation, 1 patient (11.1%) had prior ganglion block, and 4 patients (44.4%) had history of VT storm. All patients were on antiarrhythmics ranging from a beta blocker monotherapy to a combination of class Ic, class III, and a beta blocker. Seven patients (77.8%) had a defibrillator prior to CSD. All patients underwent CSD (7 with bilateral and 2 with left only) without any procedural complication. Five patients (55.6%) had recurrence of VA in 423±567 days with follow-up duration of 729±478 days. Three patients (33.3%) underwent heart transplant or LVAD and three patients (33.3%) died in 426±396 days since CSD. Overall, 3 patients (33.3%) including 2 CPVT patients and one NICM patient with normal EF were free of death, sustained VT, or advanced heart failure therapies. Conclusions: CSD via cautery ablation is safe and effective for patients with refractory VA to antiarrhythmics and/or VT ablation. Success rate appeared to be higher in patients with CPVT and normal EF. Lower rate of survival and freedom from VT or transplant/LVAD compared to published literature may reflect our sick population.

Abstract 15291: Early Outcomes With Left Cardiac Sympathetic Denervation for Medically Refractory Idiopathic Ventricular Fibrillation

Introduction: Treatment options for patients with recurrent ventricular arrhythmias (VAs) refractory to pharmacotherapy and/or ablation are minimal. Although left cardiac sympathetic denervation (LCSD) is well established in long QT syndrome (LQTS) and catecholaminergic polymorphic ventricular tachycardia (CPVT), LCSD’s role in idiopathic ventricular fibrillation (IVF) is less clear. Here, we report our single-center experience regarding the early outcomes of LCSD in patients with IVF. Hypothesis: To determine the efficacy of LCSD on reducing VAs in IVF patients refractory to conventional therapy. Methods: A retrospective analysis of the electronic health record of patients with IVF between January 2000 to April 2023 was performed. Cardiac event rates [defined as arrhythmic syncope/seizure, appropriate implantable cardioverter defibrillator (ICD) therapy, sudden cardiac arrest (SCA), or sudden cardiac death (SCD)] before and after LCSD for each patient were calculated and a Wilcoxon signed rank test was performed. Results: In total, 94 patients (41% female) were classified as IVF. Overall, 15/94 patients (16%) had LCSD due to refractory VAs (60% male; mean age at LCSD 36 ± 20 years) despite beta-blocker treatment (100%) or combined drug therapy (67%). In total, 14 patients (15%) had an electrophysiology study performed before LCSD of which 10 (67%) had VAs ablation. All patients had a structurally normal heart and genetic testing performed in 14/15 patients (93%) confirmed absence of genetic cardiomyopathies and channelopathies. SCA was the sentinel event in 10 of 15 patients (67%); 14 patients (93%) had an ICD in place. The average follow-up time after LCSD was 3 ± 4 years. The VA event rate before LCSD was 4 ± 3 events per year and was reduced to 1 ± 3 per year (p&lt;0.04) after LCSD. Patients had a median of 3.2 less events per year after LCSD (p=0.02) with 7 patients (47%) having no post-LCSD recurrences thus far while 3 (20%) patients were deemed LCSD non-responders with no reduction of event rate. Conclusions: LCSD represents a substrate-independent, anti-fibrillatory treatment option for patients with life-threatening, genetic arrhythmias. While not curative, the early outcomes of LCSD for patients with medically refractory IVF are promising.

Future direction of substrate-based catheter ablation in Brugada syndrome and other inherited primary arrhythmia syndromes: Systematic review and meta-analysis.

Inherited Primary Arrhythmias Syndromes (IPAS), especially Brugada syndrome (BrS), have been associated with arrhythmogenic substrates that can be targeted through ablation. This meta-analysis evaluated the outcomes of catheter ablation (CA) in different types of IPAS based on procedural guidance and location. A systematic search was conducted across multiple databases to identify studies reporting on ventricular arrhythmia (VA) events before and after CA in IPAS, including BrS, Long-QT syndrome (LQTS), Early repolarization syndrome (ERS), and Idiopathic ventricular fibrillation (IVF). The primary outcomes were VA recurrence and VA burden, evaluated through conditional subgroup analysis. Procedural data were collected as secondary outcomes. A total of 21 studies involving 584 IPAS patients who underwent CA were included. Following a mean follow-up duration of 33.5 months, substrate-based ablation demonstrated efficacy in reducing VA recurrence across all types of IPAS [RR 0.23; 95% CI (0.13-0.39); p < .001; I 2 = 74%]. However, activation guidance ablation was found to be effective only in IVF cases. Although recurrences still occurred, CA was successful in reducing VA burden [MD -4.70; 95% CI (-6.11-(-3.29); p < .001; I 2 = 74%]. The mean size of arrhythmogenic substrate was 15.70 cm2 [95% CI (12.34-19.99 cm2)], predominantly distributed in the epicardial right ventricular outflow tract (RVOT) in BrS cases and LQTS [Proportion 0.99; 95% CI (0.96-1.00) and Proportion 0.82; 95% CI ( 0.59-1.00), respectively]. Substrate-based CA has demonstrated effective prevention of VA and reduction in VA burden in IPAS cases.

Management of refractory intramural left ventricular summit ventricular arrhythmia: Acute success using bipolar radiofrequency catheter ablation with recurrence.

Bipolar radiofrequency catheter ablation (RFCA) is a novel strategy for refractory or recurrent ventricular arrhythmias (VAs) resistant to conventional ablation methods. Lesions created during bipolar RFCA are larger than those created during sequential unipolar ablation. We present a case of refractory LV summit VAs, which identified the origin using a 2.7-F over-the-wire microelectrodes catheter, and it was successfully treated with bipolar RFCA in the acute phase.

Myocardial scarring and recurrence of ventricular arrhythmia in patients surviving an out-of-hospital cardiac arrest.

Prediction of recurrent ventricular arrhythmia (VA) in survivors of an out-of-hospital cardiac arrest (OHCA) is important, but currently difficult. Risk of recurrence may be related to presence of myocardial scarring assessed with late gadolinium enhancement cardiac magnetic resonance (LGE-CMR). Our study aims to characterize myocardial scarring as defined by LGE-CMR in survivors of a VA-OHCA and investigate its potential role in the risk of new VA events. Between 2015 and 2022, a total of 230 VA-OHCA patients without ST-segment elevation myocardial infarction had CMR before implantable cardioverter-defibrillator implantation for secondary prevention at Copenhagen University Hospital, Rigshospitalet, and Hospital Clínic, University of Barcelona, of which n = 170 patients had a conventional (no LGE protocol) CMR and n = 60 patients had LGE-CMR (including LGE protocol). Scar tissue including core, border zone (BZ) and BZ channels were automatically detected by specialized investigational software in patients with LGE-CMR. The primary endpoint was recurrent VA. After exclusion, n = 52 VA-OHCA patients with LGE-CMR and a mean left ventricular ejection fraction of 49 ± 16% were included, of which 18 (32%) patients reached the primary endpoint of VA. Patients with recurrent VA in exhibited greater scar mass, core mass, BZ mass, and presence of BZ channels compared with patients without recurrent VA. The presence of BZ channels identified patients with recurrent VA with 67% sensitivity and 85% specificity (area under the ROC curve (AUC) 0.76; 95% CI: 0.63-0.89; p < .001) and was the strongest predictor of the primary endpoint. The presence of BZ channels was the strongest predictor of recurrent VA in patients with an out of-hospital cardiac arrest and LGE-CMR.

COVID-19 as a potential trigger for refractory arrhythmias and electrical storm in a patient with dilated cardiomyopathy: a case report

Arrhythmias occur both in the acute coronavirus disease 2019 (COVID-19) and in the post-acute period, which may be associated with the long-term SARS-CoV-2 persistence. In a case report, patient with primary dilated cardiomyopathy, an implanted cardioverter-defibrillator, recurrent ventricular arrhythmias, and an electrical storm are presented. The patient was repeatedly hospitalized in a city hospital, where electrical cardioversion, antiarrhythmic therapy, radiofrequency ablation of recurrent ventricular tachycardia regions, including emergency ("lifesaving") combined catheter radiofrequency destruction of the electrical storm substrate, was performed. Subsequently, against the background of ongoing postoperative therapy, massive pulmonary embolism (PE) suddenly developed, which led to the death. Autopsy established that the cause of the patient’s death was massive pulmonary embolism; SARS-CoV-2 and enterovirus was detected in the myocardium. Based on an autopsy study, the patient was diagnosed with primary dilated cardiomyopathy with secondary active chronic lymphocytic myocarditis.

Bilateral Cardiac Sympathetic Denervation as a Safe Therapeutic Option for Ventricular Arrhythmias.

The recurrence of ventricular arrhythmias (VAs) in patients who have already undergone treatment with antiarrhythmic medication, catheter ablation, and the insertion of implantable cardioverter defibrillators is not uncommon. Recent studies have shown that bilateral cardiac sympathetic denervation (BCSD) effectively treats VAs. However, only a limited number of studies have confirmed the safety of BCSD as a viable therapeutic option for VAs. This single-center study included 10 patients, who had a median age of 54 years (interquartile range [IQR], 45-65 years) and a median ejection fraction of 58.5% (IQR, 56.2%-60.8%), with VAs who underwent video-assisted BCSD. BCSD was executed as a single-stage surgery for 8 patients, while the remaining 2 patients initially underwent left cardiac sympathetic denervation followed by right cardiac sympathetic denervation. We evaluated postoperative complications, the duration of hospital stays, and VA-related symptoms before and after surgery. The median hospital stay after surgery was 2 days (IQR, 2-3 days). The median surgical time for BCSD was 113 minutes (IQR, 104-126 minutes). No significant complications occurred during hospitalization or after discharge. During the median follow-up period of 13.5 months (IQR, 10.5-28.0 months) from surgery, no VA-related symptoms were observed in 70% of patients. The benefits of a short postoperative hospitalization and negligible complications make BCSD a safe, alternative therapeutic option for patients suffering from refractory VAs.