Polymorphic Ventricular Arrhythmias Research Articles

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.

First experiences with protected VT ablation using surgical Impella 5.5

Abstract Introduction Ablation of ventricular arrhythmias (VA) is still challenging due to the complex substrate of the underlying heart disease. Depending on specific risk factors acute hemodynamic decompensation during or after VT ablation procedures may occur and hemodynamic support may be required. Protected VA ablation with different devices has been evaluated but associated complications like bleeding, vascular closure or weaning from the device have been restrictive. We present data on a dedicated approach to patients with anticipated hemodynamic deterioration using preventive surgical Impella support. Method 5 patients (2 female) underwent protected VT ablation under our standardized protocol. Indication for Impella support was severely impaired left ventricular function and multiple medical therapy refractory ventricular arrhythmias. 4 patients had conventional VT ablation before. Mean age was 66,8 years, mean CHADSVASC 4,4, 1 patient with non-ischemic cardiomyopathy (CMP), 1 with hypertrophic non-obstructive CMP, 3 patients with ischemic CMP. Mean EF was 20%, mean mixed venous saturation was 36 %, mean PAINESD score 27. In all patients a 5.5. Impella was implanted surgically 1 day before planned VT ablation via the right subclavian artery. VT ablation procedure started with substrate mapping, VT induction and activation mapping of the inducible VT to identify the critical VT isthmus. Ablation was directed to dissection of the critical isthmus of inducible VAs and elimination of all late potentials within low voltage areas. The Impella device was explanted after weaning off the hemodynamic support. Results Implantation of Impella 5.5 was successfully performed in all patients in general anesthesia without any complication via surgical approach. Specifically, no access site vascular complications were noted. In 4 patients the VT ablation procedure was performed in analgosedation, 1 patient in GA as this patient was intubated due to recurrent VA requiring defibrillation. Mean procedure time was 125 min, radiation time 1,3 min, inducible VTs 1,3 , median 2 morphologies. In all patients all inducible VTs could be eliminated, in 1 patient polymorphic VA was still inducible at the end of the procedure. Impella was explanted after mean 5,2 days (3-11 days). No complications occurred. All patients were discharged alive on heart failure medication and in 2 patients with amiodaron. At a mean follow up of 3.5 months, all patients are alive without VA recurrence and heart failure decompensation. Conclusion Surgical Impella implantation for protected VT ablation in severe heart failure patients is feasible and allows for effective VT mapping and ablation. Access site safety and protection for heart failure decompensation in addition to the possibility of individually mobilisation and weaning after the procedure make this protocol an attractive option. Prospective evaluation of standardized indication is needed.

Congenital Long QT Syndrome in Children and Adolescents: A General Overview.

Congenital long QT syndrome (LQTS) represents a disorder of myocardial repolarization characterized by a prolongation of QTc interval on ECG, which can degenerate into fast polymorphic ventricular arrhythmias. The typical symptoms of LQTS are syncope and palpitations, mainly triggered by adrenergic stimuli, but it can also manifest with cardiac arrest. At least 17 genotypes have been associated with LQTS, with a specific genotype-phenotype relationship described for the three most common subtypes (LQTS1, -2, and -3). β-Blockers are the first-line therapy for LQTS, even if the choice of the appropriate patients needing to be treated may be challenging. In specific cases, interventional measures, such as an implantable cardioverter-defibrillator (ICD) or left cardiac sympathetic denervation (LCSD), are useful. The aim of this review is to highlight the current state-of-the-art knowledge on LQTS, providing an updated picture of possible diagnostic algorithms and therapeutic management.

Catecholaminergic Polymorphic Ventricular Tachycardia: Clinical Characteristics, Diagnostic Evaluation and Therapeutic Strategies.

Catecholaminergic polymorphic ventricular tachycardia (CPVT) is a severe hereditary arrhythmia syndrome predominantly affecting children and young adults. It manifests through bidirectional or polymorphic ventricular arrhythmia, often culminating in syncope triggered by physical exertion or emotional stress which can lead to sudden cardiac death. Most cases stem from mutations in the gene responsible for encoding the cardiac ryanodine receptor (RyR2), or in the Calsequestrin 2 gene (CASQ2), disrupting the handling of calcium ions within the cardiac myocyte sarcoplasmic reticulum. Diagnosing CPVT typically involves unmasking the arrhythmia through exercise stress testing. This diagnosis emerges in the absence of structural heart disease by cardiac imaging and with a normal baseline electrocardiogram. Traditional first-line treatment primarily involves β-blocker therapy, significantly reducing CPVT-associated mortality. Adjunctive therapies such as moderate exercise training, flecainide, left cardiac sympathetic denervation and implantable cardioverter-defibrillators have been utilized with reasonable success. However, the spectrum of options for managing CPVT has expanded over time, demonstrating decreased rates of arrhythmic events. Furthermore, ongoing research into potential new therapies including gene therapies has the potential to further enhance treatment paradigms. This review aims to succinctly encapsulate the contemporary understanding of the clinical characteristics, diagnostic approach, established therapeutic interventions and the promising future directions in managing CPVT.

Cardiovascular eff ects of psychotropic drugs

Research over the past decade indicates that some psychotropic drugs increase the risk of developing arrhythmias and sudden cardiac death. Many antidepressants and antipsychotic drugs have arrhythmogenic potential and are associated with QT interval prolongation and development of ventricular arrhythmia of the “torsades de pointes” type, while some psychotropic drugs are associated with changes in ECG phenotype of Brugada syndrome and development of polymorphic ventricular arrhythmias.

Clinical profiling and outcomes of viral myocarditis manifesting with ventricular arrhythmias.

Clinical features and risk stratification of patients with viral myocarditis (VM) complicated by ventricular arrhythmias (VA) are incompletely understood. We aim to describe arrhythmia patterns and outcomes in patients with VM and early-onset VA. We present a single-centre study, enrolling patients with VM proven by endomyocardial biopsy, and evidence of VA within 24 h of hospitalization. The incidence of major adverse events (MAE), including all-cause death, severe heart failure, advanced atrioventricular blocks, or major VA, was evaluated during a 24-month follow-up (FU) and compared with a matched group of virus-negative myocarditis. Of patients with VM (n = 74, mean age 47 ± 16 years, 66% males, and left ventricular ejection fraction 51 ± 13%), 20 (27%) presented with major VA [ventricular tachycardia/ventricular fibrillation (VT/VF)], and 32 (44%) had polymorphic VA. Patients with polymorphic VA more commonly had evidence of ongoing systemic infection (24/32 vs. 10/42, P = 0.004) and experienced greater occurrence of MAE at discharge (15/32 vs. 2/42, P < 0.001). However, the incidence of MAE during FU was higher in patients with monomorphic VA compared to those with polymorphic VA (17/42 vs. 2/28, P = 0.002). Patients with monomorphic VA displayed frequently signs of chronic cardiomyopathy and had outcomes comparable with virus-negative myocarditis (log rank P = 0.929). Presentation with VT/VF was independently associated with MAE [at discharge: hazard ratio (HR) 4.7, 95% confidence interval (CI) 1.6-14.0, P = 0.005; during FU: HR 6.3, 95% CI 2.3-17.6, P < 0.001]. In patients with VM, polymorphic VA point to ongoing systemic infection and early adverse outcomes, whereas monomorphic VA suggest chronic cardiomyopathy and greater incidence of MAE during FU. Presentation with VT/VF is independently associated with MAE.

Catecholaminergic Polymorphic Ventricular Tachycardia: A Review of Therapeutic Strategies.

Catecholaminergic polymorphic ventricular tachycardia (CPVT) is an inherited arrhythmia syndrome characterized by bidirectional or polymorphic ventricular arrhythmia provoked by exercise or emotion. Most cases are caused by pathogenic variants in the gene encoding the cardiac ryanodine receptor (RYR2). The options for treating patients with CPVT have increased during the years, and evidence suggests that these have led to lower arrhythmic event rates. In addition, numerous potential new therapies are being investigated. In this review, we summarize the state of knowledge on both established and potential future treatment strategies for patients with CPVT and describe our approach to their management.

C70 WEARABLE CARDIOVERTER DEFIBRILLATOR IN LONG QT SYNDROME DURING PREGNANCY: TIME TO USE THE SHIELD

Abstract Introduction Long QT Syndrome (LQTS) is a rare cardiac channelopathy characterized by a high risk of lethal arrhythmias. Pregnancy and post–partum period may induce an increased vulnerability, so an appropriate prevention is needed. Case presentation A 31–year–old primigravid woman at 36 weeks of pregnancy was referred to our Cardiomyopathy Unit located in a tertiary centre for LQTS screening. The patient had a family history of LQTS (mother and brother) and Brugada syndrome (cousin). The 12–lead ECG (Figure 1) showed a long QT interval (QT corrected: 508 msec), while the transthoracic echocardiogram was unremarkable. The genetic test performed is still ongoing. The patient reported sporadic episodes of palpitations at rest and the following 24–hour ambulatory ECG revealed a very high burden of polymorphic ventricular arrhythmias, with about sixteen thousand premature ventricular complexes and a non–sustained ventricular tachycardia. Therefore, due to the patient’s high–risk for life–threatening arrhythmic events, metoprolol 25 mg o.d. was initiated and a wearable cardioverter defibrillator (WCD) with remote monitoring was provided during pregnancy and labour. After 3 weeks a caesarean delivery in epidural analgesia was performed and managed by a pregnancy heart team including a cardiologist, gynaecologist, obstetrician, and anaesthetist in close cardiac monitoring. No maternal or infant complications occurred, without arrhythmic episodes detected by the device. The WCD will be maintained also in the post–partum period with a narrow follow–up of the patient. Discussion In pregnant high–risk LQTS patients, beta–blockers are the first line therapeutic option, but they do not able to interrupt lethal arrythmias in out–of–hospital setting. The implantable cardiac defibrillator is not the best choice, due to the concerns about radiation exposure and anaesthesia during pregnancy. Moreover, lead–associated thrombosis and infections during pregnancy were reported in literature. The WCD is the ideal option in these cases. It is an external device suited for transient higher arrhythmic risk periods. Moreover, it allows a remote monitoring of arrhythmic burden (figure 2) which may help clinicians in guiding the follow–up and the therapeutic management of the patient. One drawback is the need of continuous patient’s compliance. Finally, a pregnancy heart team is mandatory in presence of these rare cardiac syndromes.

PO-04-222 OUTFLOW TRACT VERSUS NON-OUTFLOW TRACT VENTRICULAR ARRHYTHMIAS IN ATHLETES: MYOCARDIAL SUBSTRATE AND LONG-TERM CLINICAL OUTCOMES

Outflow tract ventricular arrhythmias (OT-VA) are common in healthy subjects without structural heart disease (SHD), and are generally considered benign. However, athlete-specific data on the clinical meaning of different ventricular arrhythmia (VA) morphologies are scarce. To assess the prevalence of SHD as well as long-term clinical and sports medicine outcomes in a cohort of athletes with OT-VA undergoing a comprehensive diagnostic assessment, by comparing them with athletes with non-outflow tract VAs (nOT-VA). We conducted a multi-center, observational, retrospective study enrolling athletes who were referred because of complex VAs (>500 PVCs/24 h, exercise-induced VAs, nonsustained or sustained ventricular tachycardia). Athletes were categorized into two groups: OT-VA, in case of monomorphic ventricular arrhythmias of left bundle branch block and inferior axis morphology; nOT-VA, in case of polymorphic VAs or monomorphic VAs of right bundle branch block or left bundle branch block and superior/intermediate axis. The two co-primary outcomes were survival free from all-cause death or sustained VAs and sports practice at last follow-up. 175 athletes with complex ventricular arrhythmias (OT-VA,n=82; nOT-VA,n=93) were included in the present analysis; clinical characteristics are resumed in the Table. Remarkably, the prevalence of signs of SHD was higher in nOT-VA compared to OT-VA (Table). A final diagnosis of idiopathic VA was more common in OT-VA compared to nOT-VA and, accordingly, catheter ablation was more commonly performed in the former group. Over a median follow-up of 61(43-85) months, there were 2 cardiac arrests and 1 appropriate ICD shock, all occurring in athletes in the nOT-VA group with in vivo evidence of SHD and polymorphic VAs, for an overall prevalence of a primary outcome event of 0 and 3% in the OT-VA and the nOT-VA groups, respectively (p=0.25). At last follow-up, 31 athletes (18%) practiced competitive sports (OT-VA vs. nOT-VA,p=0.23), while 92 (53%) were leisure-time athletes (OT-VA vs. nOT-VA,p=0.91). Our data confirm that the prevalence of an underlying SHD substrate is lower in athletes with OT-VA than in athletes with nOT-VA, and that all major adverse cardiac events occurred in athletes with polymorphic VAs. Nevertheless, a comprehensive workup with liberal use of cardiac magnetic resonance allowed the identification of SHD in a substantial minority of athletes with OT-VA, with clear implications for sports eligibility assessment.

Successful pregnancy in a high-risk catecholaminergic polymorphic ventricular tachycardia patient

Objective: To report the case of a successful pregnancy outcome in a severely symptomatic woman affected by catecholaminergic polymorphic ventricular tachycardia (CPVT) carrier of a novel variant in ryanodine receptor 2 (RYR2) followed by a review of the current literature. Case(s): A 27-year-old primigravida affected by CPVT was referred to our tertiary care hospital after an implantable cardioverter defibrillator (ICD) shock. The patient also received medical treatment with metoprolol and flecainide. A healthy baby was born by Cesarean section at 31 weeks after the onset of preterm labor and premature rupture of membranes. CPVT is a rare inherited cardiac condition characterized by episodic polymorphic ventricular arrhythmias with a structurally normal heart. These are usually triggered by exercise or emotional stress and can lead to syncope or even sudden cardiac death. Treatment of this condition comprises betablockers in isolation or in addition to other antiarrhythmics, left cardiac sympathetic denervation and/or ICD. Conclusion: This case illustrates the importance of a multidisciplinary approach in this clinical scenario and the benefits of an optimization of the medical treatment, and demonstrates that, even in severely affected patients, a successful pregnancy is possible under close control. However, the risk of arrhythmic events and the course of pregnancy remain largely unknown in patients with CPVT, and further investigation is needed.

Neuromodulation for the Treatment of Refractory Ventricular Arrhythmias

BackgroundNeuromodulation is increasingly recognized as a therapeutic strategy for patients with refractory ventricular arrhythmias (VAs). Percutaneous stellate ganglion blockade (SGB), transcutaneous magnetic stimulation (TcMS), and surgical cardiac sympathetic denervation (CSD) have all been utilized in this setting. ObjectivesThis study sought to characterize contemporary use and outcomes of these neuromodulation techniques for patients with refractory VA. MethodsThis retrospective cohort study included all patients at the Hospital of the University of Pennsylvania with antiarrhythmic drug (AAD)-refractory VA from 2019 to 2021 who were treated with SGB, TcMS, or CSD. ResultsA total of 34 patients (age 61 ± 14 years, 15 polymorphic VAs [44%], refractory to 1.8 ± 0.8 AADs) met inclusion criteria. SGB was performed on 11 patients (32%), TcMS on 19 (56%), and CSD on 7 (21%). Neuromodulation was associated with a reduction in the number of episodes of sustained VAs from 7 [IQR: 4-12] episodes in the 24 hours before the initial neuromodulation strategy to 0 [IQR: 0-1] episodes in the subsequent 24 hours (P < 0.001). During 1.2 ± 1.1 years of follow-up, 21 (62%) experienced recurrent VAs, and among those patients, the median time to recurrence was 3 [IQR: 1-25] days. Outcomes were similar among patients with monomorphic and polymorphic VAs. Among patients who had an acute myocardial infarction within 30 days before neuromodulation, the burden of VAs decreased from 11 [IQR: 7-12] episodes to 0 episodes in the 24 hours after treatment. ConclusionsAutonomic neuromodulation with SGB, TcMS, or CSD in patients with AAD-refractory VAs is safe and results in substantial acute reduction of VA although recurrent arrhythmias are common, and not all patients experience a reduction in arrhythmia burden.

DIAGNOSTIC UTILITY OF HOLTER MONITORING IN CATECHOLAMINERGIC POLYMORPHIC VENTRICULAR TACHYCARDIA

Catecholaminergic polymorphic ventricular tachycardia (CPVT) is a rare genetic arrhythmia predisposing to a high risk of sudden death during periods of adrenergic stress. The diagnosis hinges on the exercise stress test, which induces progressive polymorphic and bidirectional ventricular arrhythmias in affected patients. Genetic testing usually identifies a missense variant in the cardiac ryanodine receptor (RyR2). When arrhythmia symptoms are reported by patients, it is also common to perform a Holter monitor, which may identify ventricular arrhythmias.

TRPM4 inhibition by meclofenamate suppresses Ca2+-dependent triggered arrhythmias.

Cardiac arrhythmias are a major factor in the occurrence of morbidity and sudden death in patients with cardiovascular disease. Disturbances of Ca2+ homeostasis in the heart contribute to the initiation and maintenance of cardiac arrhythmias. Extrasystolic increases in intracellular Ca2+ lead to delayed afterdepolarizations and triggered activity, which can result in heart rhythm abnormalities. It is being suggested that the Ca2+-activated nonselective cation channel TRPM4 is involved in the aetiology of triggered activity, but the exact contribution and in vivo significance are still unclear. In vitro electrophysiological and calcium imaging technique as well as in vivo intracardiac and telemetric electrocardiogram measurements in physiological and pathophysiological conditions were performed. In two distinct Ca2+-dependent proarrhythmic models, freely moving Trpm4-/- mice displayed a reduced burden of cardiac arrhythmias. Looking further into the specific contribution of TRPM4 to the cellular mechanism of arrhythmias, TRPM4 was found to contribute to a long-lasting Ca2+ overload-induced background current, thereby regulating cell excitability in Ca2+ overload conditions. To expand these results, a compound screening revealed meclofenamate as a potent antagonist of TRPM4. In line with the findings from Trpm4-/- mice, 10 µM meclofenamate inhibited the Ca2+ overload-induced background current in ventricular cardiomyocytes and 15 mg/kg meclofenamate suppressed catecholaminergic polymorphic ventricular tachycardia-associated arrhythmias in a TRPM4-dependent manner. The presented data establish that TRPM4 represents a novel target in the prevention and treatment of Ca2+-dependent triggered arrhythmias.

УРОВЕНЬ ТЕСТОСТЕРОНА СЫВОРОТКИ КРОВИ КАК ПРЕДИКТОР ЛЕКАРСТВЕННО-ИНДУЦИРОВАННОГО УДЛИНЕНИЯ ИНТЕРВАЛА QT И ПОЛИМОРФНОЙ ЖЕЛУДОЧКОВОЙ ТАХИКАРДИИ У ПАЦИЕНТОВ МУЖСКОГО ПОЛА, ПРИНИМАЮЩИХ АНТИАРИТМИЧЕСКИЕ СРЕДСТВА III КЛАССА

Background. A decrease in serum testosterone level in men is associated with QT interval prolongation on the standard ECG due to changes in the functioning of potassium and calcium ion channels. The scientific literature provides relatively little information on the combined effects of testosterone deficiency and intake of class III antiarrhythmic drugs on the process of myocardial repolarization and development of polymorphic ventricular arrhythmias associated with drug-induced QT prolongation (LQTS). The aim of this study was to establish the prognostic value of serum testosterone levels for the development of drug- induced QT interval prolongation and polymorphic ventricular tachycardia (PVT). Material and methods. To achieve this goal, 59 male patients were examined, mainly those with coronary heart disease, arterial hypertension and cardiac arrhythmias, 29 (49.2%) of which had drug-induced LQTS and 30 (50.8%) were with normal values of the QT interval while taking antiarrhythmic therapy. All patients underwent clinical, laboratory and instrumental studies, including the determination of serum testosterone levels. Results. The patients with drug-induced LQTS had lower testosterone levels compared to patients without LQTS (p&lt;0.001), especially in the middle and older age groups according to the WHO age classification (p=0.009). An inverse correlation relationship (p&lt;0.01) was found between the serum testosterone level and a number of electrocardiographic parameters, including the duration of the corrected QT interval (R=-0.56), the interval T peak - T end (R=-0.58) and corrected cardioelectrophysiological balance index (R=-0.43). Testosterone levels were lower in patients with drug-induced LQTS and PVT than in patients without PVT (p=0.031). The testosterone value ≤13.43 nmol/ml demonstrated high sensitivity (100%) and specificity (78.43%), as well as a fairly high area under the ROC curve (0.917) and can be used to predict non-sustained PVT in male patients taking amiodarone and sotalol (OR=5.50 [95% CI 3.14; 9.63]). Conclusions. Our data indicate an important pathophysiological role of testosterone in the genesis of drug-induced LQTS and PVT development in male patients. Given the small size of the study sample, the applicability of this indicator needs to be tested on a larger group of patients.

EP News: Allied Professionals

Two articles were recently published, both investigating the treatment of catecholaminergic polymorphic ventricular tachycardia (CPVT). CPVT is an inherited arrhythmic syndrome characterized by bidirectional or polymorphic ventricular arrhythmias occurring during exercise or emotional stress. CPVT can lead to syncope and sudden cardiac death (SCD). CPVT should always be considered in young patients with structurally normal heart and electrocardiogram presenting with exercise- or stress-induced unexplained syncope or aborted SCD.

PO-698-06 NEUROMODULATION FOR THE TREATMENT OF REFRACTORY VENTRICULAR ARRHYTHMIAS

Neuromodulation of sympathetic tone is increasingly recognized as a therapeutic strategy for patients with refractory ventricular arrhythmias (VA). Percutaneous stellate ganglion blockade (SGB), transcutaneous magnetic stimulation (TcMS), and surgical sympathetic denervation (SD) have all been utilized in this setting. To describe our experience with autonomic neuromodulation for the treatment of refractory VA. This retrospective cohort study included all patients at the Hospital of the University of Pennsylvania with antiarrhythmic drug (AAD) refractory VA from 2019-2021 who were treated with SGB, TcMS, or SD. A total of 33 patients (age 60±14 years, 25 (76%) male, 14 (42%) polymorphic VA) met inclusion criteria. VA were refractory to 1.8±0.8 AAD. SGB was performed on 11 patients (33%), TcMS on 19 (56%), and SD on 6 (18%). Two patients underwent both SGB and SD, and one patient underwent both SGB and TcMS. Two patients who underwent SGB had the procedure repeated after 1 and 5 days respectively due to recurrent VA. SGB was performed on the left-side in 5 (46%) and was bilateral in 6 (54%) patients. SGB was guided by ultrasound in 9 (82%), fluoroscopy in 3 (27%), or anatomic landmarks with no imaging in 1 (9%). Lidocaine was the most common agent used (n=9). SD was performed on the left-side in 1 (17%) and was bilateral in 5 (83%). SD was performed via thoracotomy in 1 (17%) due to body habitus and via video-assisted thoracoscopic surgery in 5 (83%). There were no complications of any neuromodulation approach. Neuromodulation was associated with a reduction in the number of episodes of sustained VA from 10.4±11.3 episodes in the 24-hours prior to the initial neuromodulation strategy to 1.3±3.1 episodes in the subsequent 24-hours (p<0.001) with no decrease in 5 patients (15%). During 602±250 days of follow-up, 18 (55%) experienced recurrent ventricular arrhythmias and among those patients, the time to recurrence was 22±44 days. Recurrence was similar in patient in monomorphic (58%) vs polymorphic VA (50%). Autonomic neuromodulation with SGB, TcMS, or SD in patients with AAD refractory VT is safe and results in substantial acute reduction of VA burden in the majority although recurrent arrhythmias are common and not all patients experience a reduction in arrhythmia burden.

Pooled Analysis of Complications with Transvenous ICD Compared to Subcutaneous ICD in Patients with Catecholaminergic Polymorphic Ventricular Arrhythmia.

Background: Catecholaminergic polymorphic ventricular tachycardia (CPVT) is associated with arrhythmic events which may lead to sudden cardiac death (SCD). A leading therapy for CPVT besides medical treatment with beta-blockers is the use of an implantable cardioverter-defibrillator (ICD). For this paper we compared data from a pooled analysis to get further evidence about the complications of transvenous and subcutaneous ICDs. Methods: We gathered data from a search of PubMed, Web of Science, Cochrane Library and Cinahl. For our analysis, we chose 30 studies with a total number of 784 patients. We compared the data regarding complications caused by different ICD device types. Results: During a mean follow up of 38.9 months for the patients with ICD implantation (n = 337), data showed a complication rate of 101 (30%). A total of 330 (98%) of them received a transvenous-ICD (T-ICD) and 7 (2%) a subcutaneous-ICD (S-ICD). A total of 97 (29.4%) of the T-ICD patients and 4 (57.1%) of the S-ICD patients had at least one complication. Of the 234 complications that occurred in T-ICD patients 152 (65%) were inappropriate shocks due to supraventricular arrhythmias, T/R-wave oversensing or electrode defect, 26 (11.1%) lead fracture/failure, 1 (0.4%) electrode defect, 46 were (19.7%) events of electrical storms, 1 (0.4%) thromboembolic event, 2 (0.8%) cases of endocarditis and 6 (2.6%) infections of the ICD-pocket. Ten (100%) of the complications for the four patients with the S-ICD were an event of an inappropriate shock due to supraventricular arrhythmias, T/R-wave oversensing or electrode defect. Conclusion: Subcutaneous ICDs (S-ICD) show a certain advantage over T-ICDs regarding lead-related complications. Nevertheless, they still show problems with inappropriate shocks and other ICD related complications. Therefore, a case-by-case decision is advised, but the continuous improvement of S-ICD might make it an overall advantageous therapy option in the future.

Occurrence and morphology of ventricular arrhythmias in apparently normal hearts in relation to late gadolinium enhancement on cardiovascular magnetic resonance.

Cardiac magnetic resonance (CMR) is the gold standard for evaluating myocardial fibrosis. Few studies have explored the association between ventricular arrhythmias (VAs) and fibrosis in apparently normal hearts. We aimed to investigate the association between the occurrence and morphology of VAs and left ventricular late gadolinium enhancement (LV-LGE) in patients without known structural heart diseases. This study enrolled 78 patients with apparently normal hearts who underwent 24-h ambulatory Holter electrocardiogram (ECG) and CMR examinations simultaneously. The presence and extent of LGE was determined using CMR imaging and compared based on occurrence and morphology of VAs. The clinical characteristics were also recorded and calculated. LV-LGE was observed in 19 (37.3%) and 4 (14.8%) patients with and without VAs, respectively (P = 0.039). It was more frequently observed in patients with polymorphic VAs (P = 0.024). The polymorphic VAs had a higher tendency of LGE extent than monomorphic VAs, while the difference did not reach statistical significance (P = 0.055). In multivariable analyses, the presence of polymorphic VAs [hazard ratio (HR) 11.19, 95% CI 1.64-76.53, P = 0.014] and hypertension (HR 4.64, 95% CI 1.08-19.99, P = 0.039) were associated with greater prevalence of LV-LGE. In patients without structural heart diseases, besides hypertension, multiple VA morphologies on Holter ambulatory ECG measurements is another important marker of increased incidence of myocardial fibrosis.

ECG changes in psychiatric patients on psychotropic medications

Abstract Funding Acknowledgements Type of funding sources: None. Background Suicide and euthanasia accounts for 14.3% of deaths in those with psychiatric conditions. The rest are attributed to preventable causes such as cardiovascular disease, respiratory disease, and infections. Several psychotropic medications have been associated with sudden death due to their effect on prolonging QT interval, resulting in the development of a polymorphic ventricular arrhythmia, Torsades de Pointes (TdP). TdP may be self-limiting or lead to sudden cardiac arrest and death. Purpose This study aims to evaluate the cardiotoxic effects of psychotropic medications. Method This is a descriptive retrospective study of patients submitted to the local psychiatric wards within one year. Patients with psychotropic drug prescriptions were included while patients below 18 years old, pregnant, or did not have ECG performed were excluded. The control group consisted of sex- and age- matched patients with ECG conducted for occupational health purposes. Multiple regression models were conducted to investigate the predictors of significant ECG differences. Result Of the 154 psychiatric inpatients admitted, exclusions were 44 patients due to exclusion criteria and 19 patients due to difficulty in physical file access. The study population (n = 91) had a mean age of 36.7 years old with 40.7% female and 59.3% male. The predominant diagnoses were schizophrenia and delusional disorders (58.2%). 86 psychiatric patients (94.5%) were prescribed antipsychotic drugs (APD). A significantly higher proportion of psychiatric patients has a history of smoking (p &amp;lt; 0.001), alcohol consumption (p = 0.001), and illicit drug use (p &amp;lt; 0.001). They also exhibited significantly more co-morbid illnesses including hypertension (p = 0.022), hyperlipidaemia (p = 0.013), diabetes (p = 0.026) and thyroid disease (p = 0.023) than the control population. Psychiatric patients had a significantly higher mean heart rate (79.9 vs 69.6 ms; p &amp;lt; 0.001) and QTc interval (452.2 vs 418.6ms; p &amp;lt; 0.001). Mean QTc interval was significantly longer for psychiatric patients in both male (454.2 vs 414.5ms; p &amp;lt; 0.001) and female (449.3 vs 425.6 ms; p = 0.029) gender. Psychotropic drug use is a significant predictor for both prolonged heart rate (p &amp;lt; 0.001) and prolonged QTc interval (p &amp;lt; 0.001). Electrolyte imbalance is a significant predictor of prolonged QTc interval only (p = 0.036). One year follow of both groups detected only 1 psychiatric patient with palpitation. Conclusion Psychiatric patients on psychotropic medications have a longer baseline heart rate and QTc interval, which was not associated with MACE at 1 year. None of the underlying comorbidities and lifestyle choices were significant predictors of this. Electrolyte abnormalities and psychotropic drug use significantly predicted QTc prolongation. However, these findings were largely driven by APD use. A follow-up study of a longer period is recommended to investigate whether patients with prolonged QTc interval are of higher risk of MACE occurrence.

Changes in QTc interval after hydroxychloroquine therapy in patients with COVID-19 infection: a large, retrospective, multicentre cohort study

ObjectiveTo evaluate the extent of hydroxychloroquine-induced corrected QT (QTc) prolongation and its relation to COVID-19 infection severity and incidence of polymorphic ventricular arrhythmias and sudden arrhythmic deaths.DesignA large-scale cohort study...