Episodes Of Electrical Storm Research Articles

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 24hours. We reviewed the in-hospital outcomes and compared outcomes between patients who had no recurrence of VT/VF after the first 24hours (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 24hours (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.

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

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). 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. In 35 of 54 episodes of ES, ventricular tachycardia (VT) could be terminated within 24h 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 24h 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). Remote monitoring with an ATP-alert function during electrical storm may reduce appropriate ICD therapy through prompting early review.

Risk factors and prognostic role of an electrical storm in patients after myocardial infarction with an implanted ICD for secondary prevention.

IntroductionThe aim of our study was to determine the risk factors for electrical storm (ES) and to assess the impact of ES on the long-term prognosis in patients after myocardial infarction (MI) with an implantable cardioverter-defibrillator (ICD) for secondary prevention of sudden cardiac death (SCD).Material and methodsWe retrospectively analyzed 416 patients with coronary artery disease after MI who had an implanted ICD for secondary prevention of SCD. Fifty (12%) patients had one or more incidents of an electrical storm – the ES (+) group. We matched the reference group of 47 patients from 366 ES (–) patients.ResultsWe analyzed 3,408 episodes of ventricular arrhythmias: 3,148 ventricular tachyarrhythmic episodes in the ES (+) group (including 187 episodes of ES) and 260 in the ES (–) group. Multivariate logistic regression showed that inferior wall MI (RR = 3.98, 95% CI: 1.52–10.41) and the absence of coronary revascularization (RR = 2.92, 95% CI: 1.18–7.21) were independent predictors of ES (p = 0.0014). During 6-year observation of 97 patients, there were 39 (40%) deaths: 25 (50%) subjects in the ES (+) group and 14 (30%) in the ES (–) group (p = 0.036). Independent predictors of death were: the occurrence of ES (HR = 1.93), older age (HR = 1.06), and lower left ventricular ejection fraction (HR = 0.95) (for all p < 0.001).ConclusionsElectrical storm in patients after MI with ICD for secondary prevention is a relatively common phenomenon and has a negative prognostic significance. Myocardial infarction of the inferior wall and the absence of coronary revascularization are predisposing factors for the occurrence of an ES.

Abstract 12976: Malignant Type of Electrical Storm in Patients With an Implantable Cardiac Shock Device: Results From the Nippon Storm Study

Introduction: Electrical storm (ES) referred to as multiple device therapies is an important clinical problem in patients (pts) with an implantable cardiac shock device (ICSD), such as implantable cardioverter-defibrillator or cardiac resynchronization therapy device with defibrillator. Detailed clinical aspects of ES, however, remain unclear in the Asian large population. Methods: We analyzed the data of the Nippon Storm Study which was a prospective observational study and consisted of 1570 pts enrolled from 48 Japanese ICSD centers designed to clarify the clinical aspects of ES. The study population included 493 (31%) pts with ischemic heart disease (IHD) and 357 (23%) pts with dilated cardiomyopathy (DCM). They had a mean LVEF of 43±19 %. Results: ES occurred in 96 (6.4%) pts during a median follow-up of 28 (23-33) months. Compared to pts without ES, pts with ES showed a significantly lower left ventricular ejection fraction (43% vs 38 %, respectively, p=0.005). No significant difference regarding ES incidence was observed between pts with IHD and pts with DCM (log-rank p=0.77). A sub-analysis of the ES characteristics revealed that the mortality in patients with shock therapy during the first ES episode and those with the incidence of multiple episodes of ES during the follow-up was significantly higher than those without (12/18 vs 30/78; p=0.03, 12/18 vs 26/78, p&lt;0.01, respectively, Table). Conclusions: Shock therapy during the first ES episode and multiple episodes of ES were related to significantly higher mortality in pts with ICSD. There can be a malignant entity of ES.

Recurrent Ventricular Arrhythmia Storms in the Age of Implantable Cardioverter Defibrillator Therapy: A Comprehensive Review

Rapidly recurrent ventricular arrhythmia is not an infrequent clinical entity in the era of implantable cardioverter defibrillator therapy. Clinical presentation can vary dramatically, from multiple defibrillator shocks with hemodynamic instability, to asymptomatic delivery of anti-tachycardia pacing. Although some investigators have reported disparate prognostic implications with electrical storm, in larger trials of both primary and secondary defibrillator populations, electrical storm appears to be a harbinger of cardiac death with a notably high mortality early post event. While acute cessation of electrical storm is generally achievable with medical therapy, it is critical to recognize that the causes for subsequent mortality are often not arrhythmic in nature. Thus, the challenge for cardiovascular practitioners is to maximize substrate based therapy and modification to not only prevent further episodes of electrical storm and possibly curtail the considerable risk of subsequent cardiac mortality.

Electrical storm is an independent predictor of adverse long-term outcome in the era of implantable defibrillator therapy

Electrical storm (ES) is a life-threatening arrhythmia complication affecting patients treated with an implantable cardioverter defibrillator (ICD). Despite its increasing importance, existing data on prognosis and management of ICD patients affected by ES are limited and conflicting. We prospectively studied 169 consecutive patients receiving an ICD. Thirty-two patients presented with at least one episode of ES during the period of observation (33+/-26 months). ES patients were older (64+/-9 vs. 59+/-13 years, P=0.013) with more advanced congestive heart failure (CHF) but a similar incidence of an underlying organic heart disease. Long-term total and cardiac mortality were both increased among ES patients. Seventeen of the 32 ES patients died as opposed to 19 of the 137 ICD patients without ES (53 vs. 14%, P<0.001). In multivariate Cox regression analysis adjusted for the main confounders, history of ES was significantly and independently associated with total and cardiac mortality (risk ratio (RR)=2.13, P=0.031 and RR=2.59, P=0.019, respectively). ES is a relatively frequent complication affecting ICD patients treated for secondary prevention of sudden cardiac death (SCD). Although the acute management of this serious arrhythmia complication is usually successful, occurrence of ES is a strong independent predictor of poor outcome in ICD patients.

The use of implantable cardioverter-defibrillators in pediatric patients awaiting heart transplantation

BackgroundThis multicenter study evaluated experience with implantable cardioverter defibrillators (ICD) as a bridge to orthotopic heart transplantation (OHT) in children. MethodsThe application of ICD therapy continues to expand in pediatric populations, due in part to improved technology and new indications, including the prevention of sudden death while awaiting OHT. MethodsWe performed a retrospective review of ICD databases at 9 pediatric transplant centers. ResultsTwenty-eight patients (16 males) underwent implantation or had a preexisting ICD while awaiting OHT between 1990 and 2002. The median age at implant was 14.3 years (11 months to 21 years) with a median weight of 49 kg (11.7-88 kg). Diagnoses included cardiomyopathy (n=22), and congenital heart disease (n=6). Indications for ICD implantation included ventricular tachycardia/fibrillation (n=23), syncope (n=5), aborted sudden death with no documentation of rhythm disturbance (n=5), ventricular ectopy (n=1), and poor function (n=5). Of the 28 ICDs, 23 were implanted by a transvenous approach and 5 by epicardial route. There were 55 defibrillator discharges in 17 patients, 47 (85%) of which (in 13 patients) were appropriate. The 8 inappropriate discharges (in 6 patients) were triggered by sinus tachycardia, inappropriate sensing, and atrial flutter. The mean time from implantation to first appropriate shock was 6.9 months (1 day to 2.6 years). Twenty-one patients underwent transplantation during the study period, whereas 2 died while awaiting a donor. Morbidity included a lead fracture, 3 episodes of electromechanical dissociation, and 1 episode of electrical storm. ConclusionsICD implantation represents an effective bridge to transplantation in pediatric patients. The complication rate is low, with inappropriate device discharge due primarily to sinus tachycardia or atrial flutter. There is a high incidence of appropriate ICD therapy for malignant ventricular arrhythmias in this highly selected group of patients.

Electrical storm in patients with transvenous implantable cardioverter-defibrillators: incidence, management and prognostic implications.

The purpose of this study was to determine the precise incidence, therapeutic options and prognostic implications of electrical storm in patients with transvenous implantable cardioverter-defibrillator (ICD) systems. Approximately 50% to 70% of patients treated with an ICD receive appropriate device-based therapy within the first 2 years. Most arrhythmic events require only one appropriate ICD firing for termination. However, some patients receive multiple appropriate shocks during a short period of time, a condition referred to as "arrhythmic or electrical storm." This prospectively designed observational study comprised 136 recipients of transvenous ICDs who were followed for 403+/-242 days. Electrical storm was defined as ventricular tachycardia or fibrillation resulting in device intervention > or = 3 times during a single 24-h period. During follow-up, 57/136 patients (42%) received appropriate ICD therapy. Electrical storm occurred in 14/136 patients (10%) at an average of 133+/-135 days after ICD implantation. The mean number of arrhythmic episodes constituting electrical storm was 17+/-17 (range: 3 to 50; median 8) per patient. In 12 patients, electrical storm required hospital admission. The arrhythmia cluster could be terminated by a combined therapy with beta-blockers and intravenous amiodarone whereas class I antiarrhythmic drugs were only occasionally successful. The cumulative probability of survival as estimated by the Kaplan-Meier method showed that patients with an episode of electrical storm did not have a worse outcome compared to those without such an event. Electrical storm represents a frequent event in patients treated with modern ICDs. It occurs most commonly late after ICD implantation and can be managed by combined therapy with beta-blockers and amiodarone. Electrical storm does not independently confer increased mortality.