Clusters of ventricular tachycardias signify impaired survival in patients with idiopathic dilated cardiomyopathy and implantable cardioverter defibrillators

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.

[Electrical storm in patients with Automatic Implantable Defibrillator : A single Center study]

BACKGROUND

Electrical storms (ES) are serious cardiac emergencies associated with increased short-term mortality. The true incidence of ES in patients with an implantable cardioverter defibrillator (ICD) is still difficult to estimate because of the heterogeneous definition. The clinical presentation is variable and its management is multidisciplinary.

OBJECTIVE

The aim of the study was to analyze the epidemiological profile and evolution of a group of patients implanted with an ICD who had electrical storms detected by a home monitoring system.

METHODS

This is a single-center retrospective observational study, which included 14 patients who were implanted with ICDs, for primary or secondary prevention between 2008 and 2021. All of them were followed by home monitoring. All these patients had an ES detected by home monitoring and authenticated by ECG.

RESULTS

The mean age of the patients at the time of onset of the electrical storm was 75.4 ± 14.5 years, with extremes ranging from 49 to 101 years. Most of patients (n = 11) were male. The majority of them had underlying ischaemic cardiomyopathy (n = 12). In a third of cases (n = 5) patients were implanted for secondary prevention. The electrical storm was related to recurrent episodes of VT. No cases of VF were detected. Syncope was the most frequent clinical presentation (four patients). Nine patients received internal shocks, with an average of four shocks per patient. The triggering factor was myocardial ischaemia in four cases. Majority of patients were managed in the cardiac intensive care unit. Two patients were admitted to the intensive care unit. In addition to anti-arrhythmic treatment with amiodarone and beta blockers. Nine patients underwent ablation of ventricular tachycardia focus. Mortality was high (in half of the cases) mainly due to a cardiogenic shock.

CONCLUSION

This study shows that OR remain rare, but are still associated with high mortality. Home monitoring makes it possible to manage them earlier.

Multidisciplinary Critical Care Management of Electrical Storm: JACC State-of-the-Art Review

Electrical storm (ES) reflects life-threatening cardiac electrical instability with 3 or more ventricular arrhythmia episodes within 24 hours. Identification of underlying arrhythmogenic cardiac substrate and reversible triggers is essential, as is interrogation and programming of an implantable cardioverter-defibrillator, if present. Medical management includes antiarrhythmic drugs, beta-adrenergic blockade, sedation, and hemodynamic support. The initial intensity of these interventions should be matched to the severity of ES using a stepped-care algorithm involving escalating treatments for higher-risk presentations or recurrent ventricular arrhythmias. Many patients with ES are considered for catheter ablation, which may require the use of temporary mechanical circulatory support. Outcomes after ES are poor, including frequent ES recurrences and deaths caused by progressive heart failure and other cardiac causes. A multidisciplinary collaborative approach to the management of ES is crucial, and evaluation for heart transplantation or palliative care is often appropriate, even for patients who survive the initial episode.

Electrical Storm Has Worse Prognosis Compared to Sustained Ventricular Tachycardia after VT Ablation

Background: Electrical storm (ES) represents a serious heart rhythm disorder. This study investigates the impact of ES on acute ablation success and long-term outcomes after VT ablation compared to non-ES patients. Methods: In this large single-centre study, patients presenting with ES and undergoing VT ablation from June 2018 to April 2021 were compared to patients undergoing VT ablation due to ventricular tachyarrhythmias but without ES. The primary prognostic outcome was VT recurrence, and secondary endpoints were rehospitalization rates and cardiovascular mortality, all after a median follow-up of 22 months. Results: A total of 311 patients underwent a first VT ablation due to ventricular tachyarrhythmias and were included (63 ± 14 years; 86% male). Of these, 108 presented with ES. In the ES cohort, dilated cardiomyopathy as underlying heart disease was significantly higher (p = 0.008). Major complications were equal across both groups (all p > 0.05). Ablation of the clinical VT was achieved in 94% of all patients (p > 0.05). Noninducibility of any VT was achieved in 91% without ES and in 76% with ES (p = 0.001). Patients with ES revealed increased VT recurrence rates during follow-up (65% vs. 40%; log rank p = 0.001; HR 1.841, 95% CI 1.289–2.628; p = 0.001). Furthermore, ES patients suffered from increased rehospitalization rates (73% vs. 48%; log rank p = 0.001; HR 1.948, 95% CI 1.415–2.682; p = 0.001) and cardiovascular mortality (18% vs. 9%; log rank p = 0.045; HR 1.948, 95% CI 1.004–3.780; p = 0.049). After multivariable adjustment, ES was a strong independent predictor of VT recurrence and rehospitalization rates, but not for mortality. In a propensity score-matched cohort, patients with ES still had a higher risk of VT recurrences and rehospitalizations compared to non-ES patients. Conclusions: VT ablation in patients with ES is challenging and these patients reveal the highest risk for recurrent VTs, rehospitalization and cardiovascular mortality. These patients need close follow-ups and optimal guideline-directed therapy.

Adverse Prognosis of Patients with Septal Substrate After VT Ablation Due to Electrical Storm

BACKGROUND

Data about ventricular tachycardia (VT) ablation in patients with electrical storm (ES) is limited.

OBJECTIVES

This study sought to compare the prognostic outcome of patients undergoing VT ablation after ES with and without a septal substrate.

METHODS

In this large single-center study, consecutive patients presenting with ES and undergoing VT ablation from June 2018 to April 2021 were included. Patients with septal substrate were compared with patients without septal substrate regarding endpoints of cardiovascular mortality, VT recurrences, recurrences of the clinical VT, and rehospitalization rates.

RESULTS

A total of 107 patients undergoing a first VT ablation because of electrical storm (ES) were included (age 65 ± 13 years, 86% male, 45% ischemic cardiomyopathy). Major complications occurred in 11% of all patients with increased postinterventional third-degree atrioventricular blocks among patients with septal substrate (9% vs 0%; P = 0.063). Partial ablation successes were similar (95% with a septal substrate vs 100% without a septal substrate; P = 0.251). Complete ablation success was achieved in 63% with a septal substrate and in 87% without a septal substrate (P = 0.004). After a median 22 months of follow-up, patients with septal substrate died significantly more often from cardiovascular causes (26% vs 7%; log-rank P = 0.018). In univariate analysis cardiovascular mortality for ES patients with septal substrate was 4.1-fold higher (HR: 4.192; CI: 1.194-14.719; P = 0.025). Independent predictors of adverse outcome in multivariable regression analysis were presence of septal substrate (HR: 5.723; P = 0.025) and increased age (HR: 1.104; P = 0.003). Recurrences of any ventricular arrhythmia (67% vs 56%; log rank P = 0.554) and rehospitalization rates (80% vs 66%; log rank P = 0.515) were similar between groups. Recurrences of clinical VT were similar (7% vs 2%; P = 0.252).

CONCLUSIONS

Presence of a septal substrate is associated with adverse long-term cardiovascular mortality in patients admitted for VT ablation after ES. Despite decreased acute ablation successes in these patients, VT recurrence rates were similar to those without a septal substrate during follow-up.

Emergency Management of Electrical Storm: A Practical Overview

Electrical storm is a medical emergency characterized by ventricular arrythmia recurrence that can lead to hemodynamic instability. The incidence of this clinical condition is rising, mainly in implantable cardioverter defibrillator patients, and its prognosis is often poor. Early acknowledgment, management and treatment have a key role in reducing mortality in the acute phase and improving the quality of life of these patients. In an emergency setting, several measures can be employed. Anti-arrhythmic drugs, based on the underlying disease, are often the first step to control the arrhythmic burden; besides that, new therapeutic strategies have been developed with high efficacy, such as deep sedation, early catheter ablation, neuraxial modulation and mechanical hemodynamic support. The aim of this review is to provide practical indications for the management of electrical storm in acute settings.

Promising Therapies for Atrial Fibrillation and Ventricular Tachycardia

Sudden cardiac death due to arrhythmias, such as atrial fibrillation or ventricular tachycardia, account for 15–20% of all deaths. Myocardial infarction increases the burden of atrial fibrillation and ventricular tachycardia by structural and electrical remodeling of the heart. The current management of new-onset atrial fibrillation includes electric cardioversion with very high conversion rates and pharmacologic cardioversion, with less a than 50% conversion rate. If atrial fibrillation cannot be converted, the focus becomes the control of the symptoms ensuring a constant rhythm and rate control, without considering other contributory factors such as autonomic imbalance. Recently, a huge success was obtained by developing ablation techniques or addressing the vagal nerve stimulation. On the other hand, ventricular tachycardia is more sensitive to drug therapies. However, in cases of non-responsiveness to drugs, the usual therapeutic choice is represented by stereotactic ablative therapy or catheter ablation. This review focuses on these newly developed strategies for treatment of arrhythmias in clinical practice, specifically on vernakalant and low-level tragus stimulation for atrial fibrillation and stereotactic ablative therapy for drug-refractory ventricular tachycardia. These therapies are important for the significant improvement of the management of atrial fibrillation and ventricular tachycardia, providing: (1) a safer profile than current therapies, (2) higher success rate than current solutions, (3) low cost of delivery.

Arrhythmic Recurrence and Outcomes in Patients Hospitalized With First Episode of Electrical Storm

Electrical storm (ES) is a life-threatening condition that may lead to recurrent arrhythmias, need for ventricular mechanical support, and death. The study aimed to assess the burden of arrhythmia recurrence and in-hospital outcomes of patients admitted for ES in a large urban hospital. We performed a retrospective analysis of patients admitted with ventricular arrhythmias from January 2018 to June 2021 and identified 61 patients with ES, defined as 3 or more episodes of ventricular tachycardia (VT) or ventricular fibrillation (VF) within 24 hours. We reviewed the in-hospital outcomes and compared outcomes between patients who had no recurrence of VT/VF after the first 24 hours (34 [56%]), those with recurrence of 1 or 2 episodes of VT/VF within a 24-hour period (15 [24%]), and patients with 3 or more recurrent VT/VF events consistent with recurrent ES after the first 24 hours (12 [20%]). Patients with recurrent ES had significantly higher in-hospital mortality as compared with those with recurrent VT/VF not meeting criteria for ES or no recurrences of VT/VF (3 [25%] vs 0 [0%] vs 0 [0%]; p = 0.002). Moreover, patients with recurrent ES also had higher rates of the combined end points of ventricular mechanical support and death (7 [58%] vs 1 [6%] vs 1 [3%], p <0.001), invasive mechanical ventilation and death (10 [83%] vs 2 [13%] vs 2 [6%], p <0.001), catheter ablation or death (12 [100%] vs 7 [47%] vs 12 [35%], p <0.001) and heart transplantation and death (3 [25%] vs 2 [13%] vs 0 [0%], p = 0.018). In conclusion, patients admitted with ES have a high risk of in-hospital recurrence, associated with extremely poor outcomes.

Incidence, Predictors and Clinical Impact of Ventricular Electrical Storm in Arrhythmogenic Cardiomyopathy Patients with an Implantable Cardioverter-Defibrillator: A Single-Center Report with Medium-Term Follow-Up

Background

Implantable cardioverter–defibrillator (ICD) is the most effective strategy for prevention of ventricular tachyarrhythmia in patients with arrhythmogenic cardiomyopathy (ACM). However, some patients receive ventricular electrical storm (VES), characterized by multiple episodes of sustained ventricular tachyarrhythmia. The purpose of this study was to determine the incidence, predictors and prognostic implications of VES in ACM patients with an ICD.

Methods

A total of 88 patients with definite ACM who received an ICD and followed up continuously were included in this study. VES was defined as the occurrence of ≥3 separate episodes of sustained ventricular arrhythmias within a 24-hour period.

Results

During a median follow-up time of 4.0 years (range 1.6–6.9), VES occurred in 19/88 patients (21.6%). The interval between the ICD implantation and the first VES ranged from 1 month to 128 months. The median number of ventricular tachyarrhythmia events per VES was 7.5 (range 3–32). Multivariate analysis showed that VES was associated with a high body mass index (BMI) [adjusted hazard ratio (HR) 1.21, 95% confidence interval (CI) 1.00–1.45, P=0.048)] and extensive T-wave inversion (TWI) (HR 23.39, 95% CI 1.74–314.58, P=0.017). Kaplan–Meier method showed that patients with VES did not have a worse cardiac mortality compared to those without such an event.

Conclusion

There is a relatively high incidence of VES in ACM patients. The presence of high BMI and extensive TWI were strong predictors of VES occurrence in ACM patients with ICD. VES does not independently confer increased cardiac mortality.

Recent insights into mechanisms and clinical approaches to electrical storm

Electrical storm, characterized by repetitive ventricular tachycardia/fibrillation (VT/VF) over a short period, is becoming commoner with widespread use of implantable cardioverter-defibrillator (ICD) therapy. Electrical storm, sometimes called "arrhythmic storm" or "VT-storm", is usually a medical emergency requiring hospitalization and expert management, and significantly affects short- and long-term outcomes. This syndrome typically occurs in patients with underlying structural heart disease (ischemic or non-ischemic cardiomyopathy) or inherited channelopathies. Triggers for electrical storm should be sought but are often unidentifiable. Initial management is dictated by the hemodynamic status, while subsequent management typically involves ICD interrogation and reprogramming to reduce recurrent shocks, identification/management of triggers like electrolyte abnormalities, myocardial ischemia, or decompensated heart failure, and antiarrhythmic-drug therapy or catheter ablation. Sympathetic nervous system activation is central to the initiation and maintenance of arrhythmic storm, so autonomic modulation is a cornerstone of management. Sympathetic inhibition can be achieved with medications (particularly beta-adrenoreceptor blockers), deep sedation, or cardiac sympathetic denervation. More definitive management targets the underlying ventricular arrhythmia substrate to terminate and prevent recurrent arrhythmia. Arrhythmia targeting can be achieved with antiarrhythmic medications, catheter ablation or more novel therapies such as stereotactic radiation therapy that targets the arrhythmic substrate. Mechanistic studies point to adrenergic activation and other direct consequences of ICD-shocks in promoting further arrhythmogenesis and hypocontractility. Here, we review the pathophysiologic mechanisms, clinical features, prognosis, and therapeutic options for electrical storm. We also outline a clinical approach to this challenging and complex condition, along with its mechanistic basis.

Electrical Storm as an Independent Mortality Risk in Patients with Preserved or Moderately Reduced Left Ventricular Function

Electrical storm (ES), defined by 3 or more occurrences of ventricular arrhythmias within 24 hours, has been shown to be associated with an increased risk of mortality; however, detailed information remains lacking. We aimed to examine the incidence and determinants of ES and its impact on mortality in patients enrolled in the nationwide implantable cardioverter-defibrillator (ICD) registry.We studied 1,256 patients (age 65 ± 12 years) who had structural heart disease with an ICD. The patients were classified into reduced ejection fraction (EF < 35%; 657 (52%) patients) and preserved or moderately reduced EF (EF ≥ 35%; 599 (48%) patients).ES occurred in 49 (7%) and 36 (6%) patients in the EF < 35% and EF ≥ 35% groups (log-rank P = 0.297) during the median follow-up of 2.3 years. ICD with resynchronization therapy was associated with a lower incidence of ES in patients with EF < 35%. Non-ischemic heart disease and diuretics were associated with ES in patients with EF ≥ 35%. During the follow-up, 10/49 (20%) patients with ES and 80/608 patients (13%) without ES died in patients with EF < 35%, while 7/36 (19%) patients with ES and 38/563 patients (7%) without ES died in those with EF ≥ 35%. We have created 4 Cox multivariate models. All models showed approximately 2-fold higher hazard ratios in patients with EF ≥ 35% compared to EF < 35%.Our study showed that the determinants of ES differed between EF < 35% and EF ≥ 35%. The impact of ES for mortality was numerically higher in EF ≥ 35% than in EF < 35%, although a significant interaction was not detected.

The clinical impact of paroxysmal arrhythmias on the hospital outcomes of patients admitted with cirrhosis: propensity score matched analysis of 2011-2017 US hospitals

BACKGROUND

We evaluate the effects of paroxysmal arrhythmia on the hospital outcomes of patients admitted with cirrhosis.

RESEARCH DESIGN AND METHODS

2011-2017 National Inpatient Sample was used to isolate patients with decompensated/compensated cirrhosis, stratified by paroxysmal arrhythmia (supraventricular: PSVT and ventricular: PVT). The cohorts were matched using propensity-score matching and compared to mortality, length of stay, cost, and cardiac complications (cardioversion, cardiogenic shock, cardiac arrest, and ventricular fibrillation).

RESULTS

In compensated cirrhosis, 2,453 had PSVT with matched controls; 5,274 had PVT with matched controls. Those with PSVT had higher mortality (aOR 1.55 95%CI 1.23-1.95) and higher rates of cardioversion and cardiogenic shock; likewise, those with PVT had higher mortality (aOR 2.41 95%CI 2.09-2.78) and higher rates of all complications. In decompensated cirrhosis, 1,598 had PSVT with matched controls; 4,178 had PVT with matched controls. Those with PSVT had higher mortality (aOR 1.57 95%CI 1.28-1.93) and higher rates of cardioversion, cardiogenic shock, cardiac arrest; those with PVT had higher mortality (aOR 2.25 95%CI 1.98-2.56) and higher rates of all complications.

CONCLUSION

The findings from this study show that in either decompensated or compensated cohort, those with paroxysmal arrhythmias are at a higher risk of in-hospital mortality and adverse cardiac outcomes.

Clinical management of electrical storm: a current overview

The number of patients affected by electrical storm has been continuously increasing in emergency departments. Patients are often affected by multiple comorbidities requiring multidisciplinary interventions to achieve a clinical stability. Careful reprogramming of cardiac devices, correction of electrolyte imbalance, knowledge of underlying heart disease and antiarrhythmic drugs in the acute phase play a crucial role. The aim of this review is to provide a comprehensive overview of pharmacological treatment, latest transcatheter ablation techniques and advanced management of patients with electrical storm.

Electrical storm: Prognosis and management

Electrical storm is present when a cluster of ventricular arrhythmias (VAs) occurs within a short time frame. The most widely accepted definition is 3 or more episodes of VA within a 24-h period, although prognostic risk begins to rise when 2 or more events occur within 3months. Electrical storm often presents as a medical emergency in the form of recurrent implantable cardiac defibrillator (ICD) shocks, recurrent syncope in patients with no ICD or low cardiac output symptoms. Management often requires a multimodality approach including ICD management, pharmacologic therapy, catheter ablation and modulations of the autonomic nervous system. In this article, we review the definition, prognosis and management of electrical storm.

Efficacy of antitachycardia pacing alert by remote monitoring of implantable cardioverter-defibrillators for out-of-hospital electrical storm

BACKGROUND

Remote monitoring (RM) has been shown to reduce all-cause mortality in patients with implantable cardioverter-defibrillators or cardiac resynchronization therapy defibrillators (ICD/CRT-D). Not all devices transmit an alert for antitachycardia pacing (ATP) therapy, and it is unknown whether differences of RM alert affect the outcomes of electrical storm (ES).

METHODS

We enrolled 42 patients with ICD/CRT-D whose out-of-hospital ES were detected by RM between 2013 and 2020. We divided their 54 episodes into two groups (ATP-alert-on; 22, ATP-alert-off; 32), and clinical outcomes were compared between the two groups.

RESULTS

In 35 of 54 episodes of ES, ventricular tachycardia (VT) could be terminated within 24 h of ES onset just by ATP (ATP-alert-on: 14, ATP-alert-off: 21); however, many patients subsequently received shock delivery for VT. Among the 35 episodes, only in ATP-alert-on group, seven patients were prompted to visit our hospital without ICD shock through confirmation of ES by ATP-alert. Episodes that led to shock delivery 24 h or longer after the ES onset were significantly less common in the ATP-alert-on group (ATP-alert-on: 1/14, ATP-alert-off: 9/21, p = .03). Although there were no significant differences in the number of shock deliveries between episodes in the two groups, the number of ATP deliveries were significantly fewer in the ATP-alert-on group (12[7-26] vs. 29[16-53] in ATP-alert-off group, p = .03). Multivariate logistic regression analyses showed that the only ATP-alert significantly reduced ATP deliveries (HR = 0.14, 95%CI = 0.04-0.57, p = .003).

CONCLUSION

Remote monitoring with an ATP-alert function during electrical storm may reduce appropriate ICD therapy through prompting early review.

Electrical storm reveals worse prognosis compared to myocardial infarction complicated by ventricular tachyarrhythmias in ICD recipients

Both acute myocardial infarction complicated by ventricular tachyarrhythmias (AMI–VTA) and electrical storm (ES) represent life-threatening clinical conditions. However, a direct comparison of both sub-groups regarding prognostic endpoints has never been investigated. All consecutive implantable cardioverter-defibrillator (ICD) recipients were included retrospectively from 2002 to 2016. Patients with ES apart from AMI (ES) were compared to patients with AMI accompanied by ventricular tachyarrhythmias (AMI–VTA). The primary endpoint was all-cause mortality at 3 years, secondary endpoints were in-hospital mortality, rehospitalization rates and major adverse cardiac event (MACE) at 3 years. A total of 198 consecutive ICD recipients were included (AMI–VTA: 56%; ST-segment elevation myocardial infarction (STEMI): 22%; non-ST-segment myocardial infarction (NSTEMI) 78%; ES: 44%). ES patients were older and had higher rates of severely reduced left ventricular ejection fraction (LVEF) < 35%. ES was associated with increased all-cause mortality at 3 years (37% vs. 19%; p = 0.001; hazard ratio [HR] = 2.242; 95% CI 2.291–3.894; p = 0.004) and with increased risk of first cardiac rehospitalization (44% vs. 12%; p = 0.001; HR = 4.694; 95% CI 2.498–8.823; p = 0.001). This worse prognosis of ES compared to AMI–VTA was still evident after multivariable adjustment (long-term all-cause mortality: HR = 2.504; 95% CI 1.093–5.739; p = 0.030; first cardiac rehospitalization: HR = 2.887; 95% CI 1.240–6.720; p = 0.014). In contrast, the rates of MACE (40% vs. 32%; p = 0.326) were comparable in both groups. At long-term follow-up of 3 years, ES was associated with higher rates of all-cause mortality and rehospitalization compared to patients with AMI–VTA.

Catheter ablation of ventricular tachycardia in patients with electrical storm, with a special focus on patients with Chagas disease

BACKGROUND

There are few reports on the benefits of catheter ablation (CA) in patients with electrical storm (ES). None of these publications included patients with Chagas disease (ChD). Our aims are to analyze (1) all the cases of ES treated with CA and (2) the subgroup of patients with ChD.

METHODS

Prospective analysis of consecutive patients with ES due to monomorphic ventricular tachycardia (VT) treated with CA.

RESULTS

We included 38 patients: 28 males; median age of 63.5 (IQR 55-71) years old; ejection fraction (LVEF) 0.30 (0.25-0.40). Sixteen patients (42.1%) had ChD. The patients experienced 21 (15-37) VT episodes and received 7 (3-13) ICD shocks before CA. Forty-six procedures were performed (7 required epicardial access). All patients experienced ES suppression after CA. After 35 (10-64) months of follow-up (1.21 procedures per patient), 23 patients (60.5%) remain free from any VT; 35 patients (92.1%) were free from ES, and 11 patients (28.9%) died from non-arrhythmic causes. One patient underwent heart transplantation. Patients with ChD were younger (60 vs. 67 years old; p = 0.033), significantly more women (50% vs. 9.1%; p = 0.005), and had higher LVEF (0.40 vs. 0.28; p < 0.001) than the other patients. Long-term outcome of ChD patients was similar to that of the overall population. Only age and LVEF independently predicted mortality.

CONCLUSION

CA was associated with acute ventricular arrhythmia suppression in all patients with ES. Freedom rates from ES and VT were 92.1% and 60.5% respectively. Despite having a lower-risk clinical profile, patients with ChD had a comparable outcome to that of the other patients.

2019 HRS/EHRA/APHRS/LAHRS expert consensus statement on catheter ablation of ventricular arrhythmias

Ventricular arrhythmias are an important cause of morbidity and mortality and come in a variety of forms, from single premature ventricular complexes to sustained ventricular tachycardia and fibrillation. Rapid developments have taken place over the past decade in our understanding of these arrhythmias and in our ability to diagnose and treat them. The field of catheter ablation has progressed with the development of new methods and tools, and with the publication of large clinical trials. Therefore, global cardiac electrophysiology professional societies undertook to outline recommendations and best practices for these procedures in a document that will update and replace the 2009 EHRA/HRS Expert Consensus on Catheter Ablation of Ventricular Arrhythmias. An expert writing group, after reviewing and discussing the literature, including a systematic review and meta-analysis published in conjunction with this document, and drawing on their own experience, drafted and voted on recommendations and summarized current knowledge and practice in the field. Each recommendation is presented in knowledge byte format and is accompanied by supportive text and references. Further sections provide a practical synopsis of the various techniques and of the specific ventricular arrhythmia sites and substrates encountered in the electrophysiology lab. The purpose of this document is to help electrophysiologists around the world to appropriately select patients for catheter ablation, to perform procedures in a safe and efficacious manner, and to provide follow-up and adjunctive care in order to obtain the best possible outcomes for patients with ventricular arrhythmias.

2019 HRS/EHRA/APHRS/LAHRS expert consensus statement on catheter ablation of ventricular arrhythmias

Ventricular arrhythmias are an important cause of morbidity and mortality and come in a variety of forms, from single premature ventricular complexes to sustained ventricular tachycardia and fibrillation. Rapid developments have taken place over the past decade in our understanding of these arrhythmias and in our ability to diagnose and treat them. The field of catheter ablation has progressed with the development of new methods and tools, and with the publication of large clinical trials. Therefore, global cardiac electrophysiology professional societies undertook to outline recommendations and best practices for these procedures in a document that will update and replace the 2009 EHRA/HRS Expert Consensus on Catheter Ablation of Ventricular Arrhythmias. An expert writing group, after reviewing and discussing the literature, including a systematic review and meta-analysis published in conjunction with this document, and drawing on their own experience, drafted and voted on recommendations and summarized current knowledge and practice in the field. Each recommendation is presented in knowledge byte format and is accompanied by supportive text and references. Further sections provide a practical synopsis of the various techniques and of the specific ventricular arrhythmia sites and substrates encountered in the electrophysiology lab. The purpose of this document is to help electrophysiologists around the world to appropriately select patients for catheter ablation, to perform procedures in a safe and efficacious manner, and to provide follow-up and adjunctive care in order to obtain the best possible outcomes for patients with ventricular arrhythmias.

Management of ventricular electrical storm: a contemporary appraisal

Ventricular electrical storm (VES) is a clinical scenario characterized by the clustering of multiple episodes of sustained ventricular arrhythmias (VA) over a short duration. Patients with VES are prone to psychological disorders, heart failure decompensation, and increased mortality. Studies have shown that 10–28% of the patients with secondary prevention ICDs can sustain VES. The triad of a susceptible electrophysiologic substrate, triggers, and autonomic dysregulation govern the pathogenesis of VES. The rate of VA, underlying ventricular function, and the presence of implantable cardioverter-defibrillator (ICD) determine the clinical presentation. A multi-faceted approach is often required for management consisting of acute hemodynamic stabilization, ICD reprogramming when appropriate, antiarrhythmic drug therapy, and sedation. Some patients may be eligible for catheter ablation, and autonomic modulation with thoracic epidural anesthesia, stellate ganglion block, or cardiac sympathetic denervation. Hemodynamically unstable patients may benefit from the use of left ventricular assist devices, and extracorporeal membrane oxygenation. Special scenarios such as idiopathic ventricular fibrillation, Brugada syndrome, Long and short QT syndrome, early repolarization syndrome, catecholaminergic polymorphic ventricular tachycardia, arrhythmogenic right ventricular cardiomyopathy, and cardiac sarcoidosis have been described as well. VES is a cardiac emergency that requires swift intervention. It is associated with poor short and long-term outcomes. A structured team-based management approach is paramount for the safe and effective treatment of this sick cohort.

A Challenging Case of Electrical Storm in an Implantable Cardioverter Defibrillator Patient

Implantable cardioverter defibrillators (ICD) have become indispensable in managing life-threatening ventricular arrhythmias. On average, 50%-70% of the patients receive a device-based therapy within the first two years post implantation. A few patients experience the electrical storm (ES). ES is a syndrome of recurrent ventricular tachycardia or fibrillation occurring two or more times in a 24-hour period, calling for the need of electrical cardioversion or defibrillation to stabilize the patient. We present the case of a patient with severe cardiomyopathy who presented with resistant ES after failing to respond initially to conventional medications like amiodarone and lidocaine. Propofol infusion was not an option due to his severe cardiomyopathy and hypotensive shock state. Aggressive treatment with intravenous medications stabilized his ES and he was eventually transferred to an outside facility for ventricular tachycardia ablation.

Ventricular tachycardia storm management in a COVID-19 patient: a case report

Background

Coronavirus disease 2019 (COVID-19) has been associated with myocardial involvement. Among cardiovascular manifestations, cardiac arrhythmias seem to be fairly common, although no specifics are reported in the literature. An increased risk of malignant ventricular arrhythmias and electrical storm (ES) has to be considered.

Case summary

We describe a 68-year-old patient with a previous history of coronary artery disease and severe left ventricular systolic disfunction, who presented to our emergency department describing cough, dizziness, fever, and shortness of breath. She was diagnosed with COVID-19 pneumonia, confirmed after three nasopharyngeal swabs. Ventricular tachycardia (VT) storm with multiple implantable cardioverter defibrillator (ICD) shocks was the presenting manifestation of cardiac involvement during the COVID-19 clinical course. A substrate-based VT catheter ablation procedure was successfully accomplished using a remote navigation system. The patient recovered from COVID-19 and did not experience further ICD interventions.

Discussion

To date, COVID-19 pneumonia associated with a VT storm as the main manifestation of cardiac involvement has never been reported. This case highlights the role of COVID-19 in precipitating ventricular arrhythmias in patients with ischaemic cardiomyopathy who were previously stable.

Electrical storm: A focused review for the emergency physician

BACKGROUND

Electrical storm is a dangerous condition presenting to the Emergency Department that requires rapid diagnosis and management.

OBJECTIVE

This article provides a review of the diagnosis and management of electrical storm for the emergency clinician.

DISCUSSION

Electrical storm is defined as ≥3 episodes of sustained ventricular tachycardia, ventricular fibrillation, or shocks from an implantable cardioverter defibrillator within 24 h. Patients may present with a wide array of symptoms. Initial evaluation should include an electrocardiogram with a rhythm strip and continuous cardiac monitoring, a medication history, assessment of hemodynamic stability, and identification of potential triggers. Management includes an antiarrhythmic and a beta blocker. Refractory patients may benefit from double-sequential defibrillation or more invasive procedures such as intra-aortic balloon pumps, catheter ablation and extracorporeal membrane oxygenation for critically ill patients. These patients will typically require admission to an intensive care unit.

CONCLUSION

Electrical storm is a condition associated with significant morbidity and mortality. It is important for clinicians to be aware of the current evidence regarding the evaluation and management of these patients.

Mortality Risk Increases With Clustered Ventricular Arrhythmias in Patients With Implantable Cardioverter-Defibrillators

OBJECTIVES

This study sought to examine the adverse prognosis associated with ventricular arrhythmia clusters that falls outside the current electrical storm definition.

BACKGROUND

Electrical storm is most frequently defined as a cluster of ≥3 episodes of ventricular arrhythmia (VA) in a 24-h period. This definition has been associated with adverse cardiovascular outcomes and mortality, but the effect of lesser and greater clustering of arrhythmias has not been described.

METHODS

Among all patients in the Resynchronization in Ambulatory Heart Failure trial, 14,515 implantable cardioverter-defibrillator-detected events with data available were rigorously adjudicated in blinded fashion. Arrhythmia incidence was examined for clustering, defined as 2 or more VA events occurring within 3 months. The prognostic importance of clustering was analyzed by varying the cluster length and number of events used to define a cluster. Mortality rates of groups with clustered arrhythmias were compared to patients with no arrhythmia or with unclustered arrhythmia.

RESULTS

The trial included 1,764 patients, among whom 465 patients had two or more VA episodes within 3 months, whereas 406 had unclustered arrhythmias. Compared to patients with no arrhythmia, patients experiencing unclustered VA had increased risk of death (hazard ratio [HR]: 1.45; 95% confidence interval [CI]: 1.09 to 1.93; p = 0.011), whereas the risk was even higher in patients with clustered arrhythmia (HR: 2.68; 95% CI: 2.13 to 3.36; p < 0.0001). Mortality risk increased with higher VA burden (number of VAs in a cluster) and shorter cluster length. This was observed in all groups tested, including the cluster with the least VA burden in the longest cluster length tested (2 VA episodes occurring within 3 months) (mortality HR: 2.85; 95% CI: 1.95 to 4.17; p < 0.0001). Although clustered arrhythmias terminated with antitachycardia pacing were associated with increased mortality, clusters terminated with implantable cardioverter-defibrillator shocks were associated with still higher mortality risk.

CONCLUSIONS

Significant adverse prognostic association of clustered VAs is observable with even 2 VA events within 3 months and increases with higher cluster density.

Propranolol Versus Metoprolol for Treatment of Electrical Storm in Patients With Implantable Cardioverter-Defibrillator

BACKGROUND

Electrical storm (ES), characterized by unrelenting recurrences of ventricular arrhythmias, is observed in approximately 30% of patients with implantable cardioverter-defibrillators (ICDs) and is associated with high mortality rates.

OBJECTIVES

Sympathetic blockade with β-blockers, usually in combination with intravenous (IV) amiodarone, have proved highly effective in the suppression of ES. In this study, we compared the efficacy of a nonselective β-blocker (propranolol) versus a β₁-selective blocker (metoprolol) in the management of ES.

METHODS

Between 2011 and 2016, 60 ICD patients (45 men, mean age 65.0 ± 8.5 years) with ES developed within 24 h from admission were randomly assigned to therapy with either propranolol (160 mg/24 h, Group A) or metoprolol (200 mg/24 h, Group B), combined with IV amiodarone for 48 h.

RESULTS

Patients under propranolol therapy in comparison with metoprolol-treated individuals presented a 2.67 times decreased incidence rate (incidence rate ratio: 0.375; 95% confidence interval: 0.207 to 0.678; p = 0.001) of ventricular arrhythmic events (tachycardia or fibrillation) and a 2.34 times decreased rate of ICD discharges (incidence rate ratio: 0.428; 95% CI: 0.227 to 0.892; p = 0.004) during the intensive care unit (ICU) stay, after adjusting for age, sex, ejection fraction, New York Heart Association functional class, heart failure type, arrhythmia type, and arrhythmic events before ICU admission. At the end of the first 24-h treatment period, 27 of 30 (90.0%) patients in group A, while only 16 of 30 (53.3%) patients in group B were free of arrhythmic events (p = 0.03). The termination of arrhythmic events was 77.5% less likely in Group B compared with Group A (hazard ratio: 0.225; 95% CI: 0.112 to 0.453; p < 0.001). Time to arrhythmia termination and length of hospital stay were significantly shorter in the propranolol group (p < 0.05 for both).

CONCLUSIONS

The combination of IV amiodarone and oral propranolol is safe, effective, and superior to the combination of IV amiodarone and oral metoprolol in the management of ES in ICD patients.

Electrical Storm Due to Active Myocardial Ischemia in the Right Coronary Artery Territory – Case Report

Electrical storm is defined by at least three episodes of sustained ventricular tachyarrhythmias or appropriate shocks given by implantable cardiac defibrillator devices (ICD), occurring within a period of 24 hours. In the present manuscript, we present the case of a 69-year-old female patient with previous aortocoronary bypass, who was admitted from the Emergency Department after presenting several episodes of syncope in prehospital settings and presented 4 episodes of sustained ventricular tachycardia which required electrical cardioversion. The arrhythmia disappeared after percutaneous revascularization of a chronic occlusion in the right coronary artery. In this case, the implantation of an ICD was avoided, as a reversible cause of ES has been identified and treated.

2019 HRS/EHRA/APHRS/LAHRS expert consensus statement on catheter ablation of ventricular arrhythmias

Ventricular arrhythmias are an important cause of morbidity and mortality and come in a variety of forms, from single premature ventricular complexes to sustained ventricular tachycardia and fibrillation. Rapid developments have taken place over the past decade in our understanding of these arrhythmias and in our ability to diagnose and treat them. The field of catheter ablation has progressed with the development of new methods and tools, and with the publication of large clinical trials. Therefore, global cardiac electrophysiology professional societies undertook to outline recommendations and best practices for these procedures in a document that will update and replace the 2009 EHRA/HRS Expert Consensus on Catheter Ablation of Ventricular Arrhythmias. An expert writing group, after reviewing and discussing the literature, including a systematic review and meta-analysis published in conjunction with this document, and drawing on their own experience, drafted and voted on recommendations and summarized current knowledge and practice in the field. Each recommendation is presented in knowledge byte format and is accompanied by supportive text and references. Further sections provide a practical synopsis of the various techniques and of the specific ventricular arrhythmia sites and substrates encountered in the electrophysiology lab. The purpose of this document is to help electrophysiologists around the world to appropriately select patients for catheter ablation, to perform procedures in a safe and efficacious manner, and to provide follow-up and adjunctive care in order to obtain the best possible outcomes for patients with ventricular arrhythmias.

Prognostic impact of recurrences in patients with electrical storm

OBJECTIVES

The study sought to assess the prognostic impact of recurrences of electrical storm (ES-R) on mortality, rehospitalization and major adverse cardiac events (MACE).

BACKGROUND

Data on the prognostic impact of ES-R is rare.

METHODS

All consecutive ES patients with an implantable cardioverter defibrillator (ICD) were included retrospectively from 2002 to 2016. Patients with ES-R were compared to patients without ES-R. The primary endpoint was all-cause mortality, secondary endpoints were in-hospital mortality, rehospitalization and MACE.

RESULTS

A total of 87 consecutive ES patients with an ICD were included, of which 26% presented with ES-R at 2.5 years of follow-up. ES-R patients revealed lower LVEF compared to non-ES-R patients (91% vs. 61%; p = .081). There was a numerically higher rate of the primary endpoint of all-cause mortality at 2.5 years (50% vs. 32%; log-rank p = .137). Furthermore, ES-R was associated with increasing rates of rehospitalization (64% vs. 37%; p = .031; HR 1.985; 95% CI 1.025-3.845; log-rank p = .042), especially of acute heart failure (32% vs. 12%; p = .001; HR 3.262; 95% CI 1.180-9.023; log rank p = .023). MACE were higher in ES-R patients (55% vs. 35%; p = .113; log rank p = .141). ES patients with LVEF ≤35% were 12.4 times more likely to develop ES-R (HR 12.417; 95% CI 1.329-115.997; p = .027).

CONCLUSION

At long-term follow-up of 2.5 years, ES-R was associated with numerically higher rates of long-term all-cause mortality and significantly higher rates of rehospitalization due to acute heart failure. LVEF ≤35% was associated with increased risk of ES-R. Condensed Abstract This study examined retrospectively the impact of recurrences of electrical storm (ES-R) on survival in 87 patients. ES-R was associated with numerically higher long-term all-cause mortality, whereas significantly higher rates of rehospitalization, respectively of acute heart failure were observed. Highlights ES-R is associated with numerically higher rates of all-cause mortality at long-term follow-up. ES-R is associated with significantly higher rates of rehospitalization and numerically higher rates of MACE at long-term follow-up, mainly due to acute heart failure. Patients with LVEF ≤35% were 12.4 times more likely to develop ES-R.

Prognostic significance of ventricular tachycardia clustering after catheter ablation in non-ischemic dilated cardiomyopathy

BACKGROUND

Ventricular tachycardia clustering (VTc) is associated with a worse clinical outcome in patients with non-ischemic dilated cardiomyopathy (NI-DCM) and implantable cardioverter defibrillator (ICD); however, its role after catheter ablation (CA) has still not been investigated. Aim of this study was to evaluate the prognostic significance of VTc after CA.

METHODS

96 consecutive patients (59 ± 13 years, 82% males) with NI-DCM underwent CA for drug-refractory VT. After CA, patients with VT recurrence were divided into two groups: (1) patients that presented with VTc defined as the occurrence of three or more appropriate ICD interventions within 2 weeks, and (2) patients without VTc.

RESULTS

At 56-months follow-up after ablation 52/96 (54%) patients had recurrent VT, 28/52 (54%) patients experienced VTc and 24/52 (46%) no VTc. When comparing patients with VTc after CA with those without, no differences in terms of age, sex, ejection fraction and cardiovascular risk factors were found. However, patients with VTc showed higher mortality rates at follow-up (54% vs 21% p = 0.04; log-rank p ≤ 0.01). No survival differences were found between patients without VT recurrence and those with VT recurrence but without VTc (29% vs 21% p = 0.77). Predictors of VTc were LVEF < 30% at follow-up and endo-epicardial scar at 3D voltage mapping. At stepwise multivariate analysis VTc and NHYA class were the only independent predictors of death (respectively, RR 3.4, CI 95% 1.16-10.3, p = 0.02; RR 4.18, CI 95% 1.3-12.6, p = 0.01).

CONCLUSIONS

VTc after CA is an independent predictor of survival and is associated with reduced LVEF at follow-up and endo-epicardial scar at 3D voltage mapping.

Electrical Storm in Patients with Implantable Cardioverter-defibrillators: A Practical Overview

Electrical storm (ES) is an increasingly common medical emergency characterized by clustered episodes of sustained ventricular arrhythmias (VAs) that lead to repeated appropriate implantable cardioverter-defibrillator (ICD) therapies. A diagnosis of ES can be made with the occurrence of three or more sustained episodes of VAs, or of three or more appropriate ICD therapies within 24 hours in patients with implanted devices. ES is associated with poor outcomes in patients with structural heart disease, particularly those with severe left ventricular dysfunction. In large clinical trials involving patients with ICDs for primary and secondary prevention, ES appears to be a predictor of cardiac death, with notably higher rates of mortality soon after the event. ES management is challenging and requires special medical attention with accurate patient risk stratification and a multidisciplinary approach that includes the use of pharmacologic therapies such as antiarrhythmic drugs (AADs) and interventional approaches like catheter ablation, surgical ablation, or sympathetic neuromodulation. Initial management involves determining and addressing the underlying ischemia, any electrolyte imbalances, and/or other causative factors. Hemodynamic support needs to be considered in high-risk patients with unstable VAs or those with severe comorbidities such as low left ventricular ejection fraction, advanced New York Heart Association class, and/or chronic pulmonary disease. Following the acute phase of ES, treatment should shift towards maximizing therapeutic efforts to address heart failure, performing revascularization, and preventing subsequent VAs. In the present manuscript, we offer an overview of the most relevant clinical aspects of ES with regard to novel therapeutic strategies.

Successful ventricular tachycardia ablation in patients with electrical storm reduces recurrences and improves survival

OBJECTIVE

The purpose of this study was to evaluate the characteristics and outcome of patients undergoing ablation after electrical storm (ES).

METHODS

Clinical and procedural characteristics, ventricular tachycardia (VT) recurrence, and mortality rates from 1940 patients undergoing VT ablation were compared between patients with and without ES.

RESULTS

The group of 677 patients with ES (34.9%) were older, were more frequently men, and had a lower ejection fraction, more advanced heart failure, and a higher prevalence of cardiovascular comorbidities as compared with those without ES (86.1% patients with ES had ≥2 comorbidities vs 71.4%; P < .001). Patients with ES had more inducible VTs (2.5 ± 1.8 vs 1.9 ± 1.9; P < .001), required longer procedures (296.1 ± 119.1 minutes vs 265.7 ± 110.3 minutes; P < .001), and had a higher in-hospital mortality (42 deaths [6.2%] vs 18 deaths [1.4%]; P < .001). At 1-year follow-up, patients with ES experienced a higher risk of VT recurrence and mortality (32.1% vs 22.6% and 20.1% vs 8.5%; long-rank, P < .001 for both). Among patients with ES, those without any inducible VT after ablation had a higher survival rate (86.3%) than did those with nonclinical VTs only (72.9%), those with clinical VTs inducible at programmed electrical stimulation (51.2%), and not-tested patients (65.0%) (long-rank, P < .001 for all). In multivariate analysis, ES remained an independent predictor of in-hospital mortality, VT recurrence, and 1-year mortality (P < .001).

CONCLUSION

Patients with ES have a high risk of VT recurrence and mortality. Patient and procedure characteristics are consistent with advanced cardiac disease and longer and more complex procedures. In patients with ES, acute procedural success is associated with a significant reduction in VT recurrence and improved 1-year survival.

Outcomes of ventricular tachycardia ablation in patients with structural heart disease: The impact of electrical storm

Aims

To investigate predictors of long-term outcomes after catheter ablation (CA) for ventricular tachycardia (VT) and the impact of electrical storm (ES) prior to index ablation procedures.

Methods

We studied consecutive patients with structural heart disease and VT (n = 328; age: 63±12 years; 88% males; 72% ischaemic cardiomyopathy; LVEF: 32±12%) who had undergone CA. According to presenting arrhythmia at baseline, they were divided into ES (n = 93, 28%) and non-ES groups. Clinical predictors of all-cause mortality were investigated and a clinically useful risk score (SCORE) was constructed.

Results

During a median follow-up of 927 days (IQR: 564–1626), 67% vs. 60% of patients (p = 0.05) experienced VT recurrence in the ES vs. the non-ES group, respectively; and 41% vs. 32% patients died (p = 0.02), respectively. Five factors were independently associated with mortality: age >70 years (hazard ratio (HR): 1.6, 95% confidence interval (CI): 1.1–2.4, p = 0.01), NYHA class ≥3 (HR: 1.9, 95% CI: 1.2–2.9, p = 0.005), a serum creatinine level >1.3 mg/dL (HR: 1.6, 95% CI: 1.1–2.3, p = 0.02), LVEF ≤25% (HR: 2.4, 95% CI: 1.6–3.5, p = 0.00004), and amiodarone therapy (HR: 1.5, 95% CI: 1.0–2.2, p = 0.03). A risk SCORE ranging from 0–4 (1 point for either high-risk age, NYHA, creatinine, or LVEF) correlated with mortality. ES during index ablation independently predicted mortality only in patients with a SCORE ≤1.

Conclusions

Advanced LV dysfunction, older age, higher NYHA class, renal dysfunction, and amiodarone therapy, but not ES, were predictors of poor outcomes after CA for VT in the total population. However, ES did predict mortality in a low-risk sub-group of patients.

Implantable cardioverter-defibrillator programming and electrical storm: Results of the OBSERVational registry On long-term outcome of ICD patients (OBSERVO-ICD)

BACKGROUND

Electrical storm (ES) is defined as 3 or more episodes of ventricular fibrillation (VF) or ventricular tachycardia (VT) within 24 hours and is associated with increased cardiac and all-cause mortality.

OBJECTIVE

The purpose of this study was to test whether aggressive implantable cardioverter-defibrillator (ICD) programming can be associated with ES.

METHODS

The OBSERVational registry On long-term outcome of ICD patients (OBSERVO-ICD) is a multicenter, retrospective registry enrolling all consecutive patients undergoing ICD implantation from 2010 to 2012 in 5 Italian high-volume arrhythmia centers. Clinical history and risk factors were collected for all patients, as were ICD therapy-related variables such as detection zones and delays. The total number of arrhythmic episodes and therapies delivered by the ICD were collected through out-of-hospital visits and remote monitoring.

RESULTS

The registry enrolled 1319 consecutive patients, of whom 62 (4.7%) experienced at least 1 ES during follow-up (median 39 months). Patients who experienced ES had a significantly lower VF detection zone (P = .002), more frequently had antitachycardia pacing therapies programmed off during capacitor charge (P = .001), and less frequently had an ICD set with delayed therapies for VT zones (P = .042) and VF zone (P = .036). Patients who experienced ES had a significantly higher incidence of death and heart failure-related death compared to patients with no ventricular arrhythmias and patients with unclustered VTs/VFs (P = .025 and P <.001, respectively).

CONCLUSION

Patients with ES had a more aggressive ICD programming setup, including lower VF detection rates, shorter detection times, and no antitachycardia pacing therapies during capacitor charge. This kind of ICD programming potentially could increase the likelihood of ES and the related risk of death.

Positive Psychotherapy to Improve Autonomic Function and Mood in ICD Patients (PAM-ICD): Rationale and Design of an RCT Currently Underway

BACKGROUND

Improving mental and physical health of patients with implantable cardioverter defibrillators (ICD) is critical because this group is at high risk for ventricular arrhythmias and sudden death and depressed or anxious cardiovascular disease (CVD) patients appear to be at even higher risk for mortality compared to nondepressed or nonanxious CVD patients. Further, autonomic dysfunction is present in these patients, and negative emotions and arrhythmias form a downward spiral further worsening mood, well-being, and cardiovascular health. Much research demonstrates that positive emotion is related to health benefits, improved physiology, and increased survival.

METHODS AND RESULTS

This is a two-arm randomized controlled trial aiming to recruit 60 adult ICD patients comparing 12 individually delivered, weekly sessions of: (1) a positive emotion-focused cognitive-behavioral therapy (Quality of Life Therapy [QOLT]), and (2) Heart Healthy Education. Autonomic functioning, heart rhythm indices, and psychosocial health are measured at baseline, 3 months, and 9 months. The first goal is feasibility and acceptability, with the primary outcome being arrhythmic event frequency data.

CONCLUSION

This study is designed to test whether QOLT produces changes in mood, quality of life/well-being, autonomic function, and arrhythmic and ICD therapy event rates. This feasibility trial is a foundational step for the next trial of QOLT to help determine whether a 3-month QOLT trial can reduce arrhythmias occurrences among ICD patients, and examine a mechanism of autonomic functioning. This study may help to develop and implement new medical or psychological therapies for ICD patients.

Electrical Storm: Incidence, Prognosis and Therapy

The term "electrical storm" indicates a life-threatening clinical condition characterized by the recurrence of hemodynamically unstable ventricular tachycardia and/or ventricular fibrillation, in particular in patients with ICD implanted for primary or secondary prevention. Although there isn't a shared definition of electrical storm, nowadays the most accepted definition refers to three or more separate arrhythmia episodes leading to ICD therapies including antitachycardia pacing or shock occurring over a single 24 hours' time period. Clinical presentation can be dramatic and triggering mechanism are not clear at all yet, but electrical storm is associated with high mortality rates and low patients quality of life, both in the acute phase and in the long term. The first line therapy is based on antiarrhythmic drugs to suppress electrical storm, but in refractory patients, interventions such as catheter ablation or in some cases surgical cardiac sympathetic denervation might be helpful. Anyhow, earlier interventional management can lead to better outcomes than persisting with antiarrhythmic pharmacologic therapy and, when available, an early interventional approach should be preferred.

Catheter ablation of drug refractory electrical storm in patients with ischemic cardiomyopathy: A single center experience

Objective:

Electrical storm (ES) is a life-threatening pathology that requires immediate and effective treatment due to increased morbidity and mortality. Catheter ablation (CA) is an effective therapeutic option, particularly in patients with drug resistant ventricular arrhythmia episodes. These procedures should only be performed in highly specialized and experienced centers. Here we aimed to assess safety and efficacy of CA in a relatively large cohort with ES in our tertiary center hospital.

Methods:

A total of 44 patients (90.9% male; mean age: 59.7±10.3 years) with ischemic cardiomyopathy undergoing CA for drug-refractory ES were prospectively evaluated. Procedures were performed using non-contact and electro-anatomic mapping systems. Long-term follow-up analysis addressed the predictors of ES recurrence and cardiac mortality.

Results:

Acute success rates for clinical and non-clinical VTs were 90.8% and 55.5%, respectively. A mean follow-up at 28±11 months revealed cardiac mortality in 8 (18%) patients, 39 (88.6%) patients were free from the ES, and 24 (55%) patients remained free from both ES and paroxysmal VT episodes. In multivariate regression analysis, recurrence of ES (OR=3.11, 95% CI: 1.65-4.62, p=0.001), LVEF, and serum creatinine were found as independent predictors of cardiac mortality. In addition, substrate based ablation, implantation of ICD for secondary prophylaxis, LVEF, and serum creatinine were good predictors of ES recurrence.

Conclusion:

Catheter ablation for ventricular arrhythmias in the course of ES in patients with ischemic cardiomyopathy is safe with an acceptable success rate. (Anatol J Cardiol 2016; 16: 159-64)

Electrical storm: A clinical and electrophysiological overview

Electrical storm (ES) is a clinical condition characterized by three or more ventricular arrhythmia episodes leading to appropriate implantable cardioverter-defibrillator (ICD) therapies in a 24 h period. Mostly, arrhythmias responsible of ES are multiple morphologies of monomorphic ventricular tachycardia (VT), but polymorphic VT and ventricular fibrillation can also result in ES. Clinical presentation is very dramatic in most cases, strictly related to the cardiac disease that may worsen electrical and hemodynamic decompensation. Therefore ES management is challenging in the majority of cases and a high mortality is the rule both in the acute and in the long-term phases. Different underlying cardiomyopathies provide significant clues into the mechanism of ES, which can arise in the setting of structural arrhythmogenic cardiomyopathies or rarely in patients with inherited arrhythmic syndrome, impacting on pharmacological treatment, on ICD programming, and on the opportunity to apply strategies of catheter ablation. This latter has become a pivotal form of treatment due to its high efficacy in modifying the arrhythmogenic substrate and in achieving rhythm stability, aiming at reducing recurrences of ventricular arrhythmia and at improving overall survival. In this review, the most relevant epidemiological and clinical aspects of ES, with regard to the acute and long-term follow-up implications, were evaluated, focusing on these novel therapeutic strategies of treatment.

Optimal antiarrhythmic drug therapy for electrical storm

Electrical storm, defined as 3 or more separate episodes of ventricular tachycardia or ventricular fibrillation within 24 hours, carries significant morbidity and mortality. These unstable ventricular arrhythmias have been described with a variety of conditions including ischemic heart disease, structural heart disease, and genetic conditions. While implantable cardioverter defibrillator implantation and ablation may be indicated and required, antiarrhythmic medication remains an important adjunctive therapy for these persons.