Development and Validation of a New Risk Prediction Score for Life-Threatening Ventricular Tachyarrhythmias in Laminopathies.

BACKGROUND: An accurate estimation of the risk of life-threatening (LT) ventricular tachyarrhythmia (VTA) in patients with LMNA mutations is crucial to select candidates for implantable cardioverter-defibrillator implantation. METHODS: We included 839 adult patients with LMNA mutations, including 660 from a French nationwide registry in the development sample, and 179 from other countries, referred to 5 tertiary centers for cardiomyopathies, in the validation sample. LTVTA was defined as (1) sudden cardiac death or (2) implantable cardioverter defibrillator-treated or hemodynamically unstable VTA. The prognostic model was derived using the Fine-Gray regression model. The net reclassification was compared with current clinical practice guidelines. The results are presented as means (SD) or medians [interquartile range]. RESULTS: We included 444 patients, 40.6 (14.1) years of age, in the derivation sample and 145 patients, 38.2 (15.0) years, in the validation sample, of whom 86 (19.3%) and 34 (23.4%) experienced LTVTA over 3.6 [1.0-7.2] and 5.1 [2.0-9.3] years of follow-up, respectively. Predictors of LTVTA in the derivation sample were: male sex, nonmissense LMNA mutation, first degree and higher atrioventricular block, nonsustained ventricular tachycardia, and left ventricular ejection fraction (https://lmna-risk-vta.fr). In the derivation sample, C-index (95% CI) of the model was 0.776 (0.711-0.842), and the calibration slope 0.827. In the external validation sample, the C-index was 0.800 (0.642-0.959), and the calibration slope was 1.082 (95% CI, 0.643-1.522). A 5-year estimated risk threshold ≥7% predicted 96.2% of LTVTA and net reclassified 28.8% of patients with LTVTA in comparison with the guidelines-based approach. CONCLUSIONS: In comparison with the current standard of care, this risk prediction model for LTVTA in laminopathies significantly facilitated the choice of candidates for implantable cardioverter defibrillators. CLINICAL TRIAL REGISTRATION: URL: https://www.clinicaltrials.gov. Unique identifier: NCT03058185.

Diagnosis, family screening, and treatment of inherited arrhythmogenic diseases in Europe: results of the European Heart Rhythm Association Survey.

The spectrum of inherited arrhythmogenic diseases (IADs) includes disorders without overt structural abnormalities (i.e. primary inherited arrhythmia syndromes) and structural heart diseases (i.e. arrhythmogenic ventricular cardiomyopathy, hypertrophic cardiomyopathy). The aim of this European Heart Rhythm Association (EHRA) survey was to evaluate current clinical practice and adherence to 2015 European Society of Cardiology Guidelines regarding the management of patients with IADs. A 24-item centre-based online questionnaire was presented to the EHRA Research Network Centres and the European Cardiac Arrhythmia Genetics Focus Group members. There were 46 responses from 20 different countries. The survey revealed that 37% of centres did not have any dedicated unit focusing on patients with IADs. Provocative drug challenges were widely used to rule-out Brugada syndrome (BrS) (91% of centres), while they were used in a minority of centres during the diagnostic assessment of long-QT syndrome (11%), early repolarization syndrome (12%), or catecholaminergic polymorphic ventricular tachycardia (18%). While all centres advised family clinical screening with electrocardiograms for all first-degree family members of patients with IADs, genetic testing was advised in family members of probands with positive genetic testing by 33% of centres. Sudden cardiac death risk stratification was straightforward and in line with current guidelines for hypertrophic cardiomyopathy, while it was controversial for other diseases (i.e. BrS). Finally, indications for ventricular mapping and ablation procedures in BrS were variable and not in agreement with current guidelines in up to 54% of centres.

Implantable cardiac defibrillator leads dysfunction after LVAD implantation.

BACKGROUND: Implantable cardioverter-defibrillator (ICD) lead dysfunction has been reported after left ventricular assist device (LVAD) implantation in limited single-center studies. We aimed at describing and characterizing the incidence of ICD lead parameters dysfunction after LVAD implantation. METHODS: Among the 652 patients enrolled in the ASSIST-ICD study, only patients with an ICD prior to LVAD were included (n = 401). ICD lead parameters dysfunction following LVAD implantation is defined as follows: (a) >50% decrease in sensing threshold, (b) pacing lead impedance increase/decrease by >100Ω, and (c) >50% increase in pacing threshold. RESULTS: One hundred twenty-two patients with an ICD prior to LVAD had available ICD interrogation reports prior and after LVAD. A total of 67 (55%) patients exhibited at least one significant lead dysfunction: 17 (15%) exhibited >50% decrease in right ventricular (RV) sensing, 51 (42%) had >100 Ω increase/decrease in RV pacing impedance, and 24 (20%) experienced >50% increase in RV pacing threshold. A total of 52 patients experienced ventricular arrhythmia during follow-up and all were successfully detected and treated by the device. All lead dysfunction could be managed conservatively. CONCLUSION: More than 50% of LVAD-recipients may experience >1 significant change in lead parameters but none had severe clinical consequences.

Risk factors and prognostic impact of left ventricular assist device-associated infections.

BACKGROUND: Left ventricular assist device (LVAD)-associated infections may be life-threatening and impact patients' outcome. We aimed to identify the characteristics, risk factors, and prognosis of LVAD-associated infections. METHODS: Patients included in the ASSIST-ICD study (19 centers) were enrolled. The main outcome was the occurrence of LVAD-associated infection (driveline infection, pocket infection, or pump/cannula infection) during follow-up. RESULTS: Of the 652 patients enrolled, 201 (30.1%) presented a total of 248 LVAD infections diagnosed 6.5 months after implantation, including 171 (26.2%), 51 (7.8%), and 26 (4.0%) percutaneous driveline infection, pocket infection, or pump/cannula infection, respectively. Patients with infections were aged 58.7 years, and most received HeartMate II (82.1%) or HeartWare (13.4%). Most patients (62%) had implantable cardioverter-defibrillators (ICDs) before LVAD, and 104 (16.0%) had ICD implantation, extraction, or replacement after the LVAD surgery. Main pathogens found among the 248 infections were Staphylococcus aureus (n = 113' 45.4%), Enterobacteriaceae (n = 61; 24.6%), Pseudomonas aeruginosa (n = 34; 13.7%), coagulase-negative staphylococci (n = 13; 5.2%), and Candida species (n = 13; 5.2%). In multivariable analysis, HeartMate II (subhazard ratio, 1.56; 95% CI, 1.03 to 2.36; P = .031) and ICD-related procedures post-LVAD (subhazard ratio, 1.43; 95% CI, 1.03-1.98; P = .031) were significantly associated with LVAD infections. Infections had no detrimental impact on survival. CONCLUSIONS: Left ventricular assist device-associated infections affect one-third of LVAD recipients, mostly related to skin pathogens and gram-negative bacilli, with increased risk with HeartMate II as compared with HeartWare, and in patients who required ICD-related procedures post-LVAD. This is a plea to better select patients needing ICD implantation/replacement after LVAD implantation.

Catheter ablation reduces ventricular tachycardia burden in patients with arrhythmogenic right ventricular cardiomyopathy: insights from a north-western French multicentre registry.

Aims: Studies assessing radiofrequency ablation (RFA) of ventricular tachycardia (VT) in arrhythmogenic right ventricular cardiomyopathy (ARVC) report VT recurrences, but have not evaluated the impact of RFA on relevant clinical events during follow-up. We aimed to investigate relevant RFA outcomes in a multicentric registry. Methods and results: This study included 49 patients with ARVC (46 with definite diagnosis, 3 with borderline diagnosis according to revised Task Force Criteria) who underwent 92 RFA procedures (83 endocardial, 9 combined endo-epicardial) between 1999-2015. Ventricular tachycardia recurrences and VT burden were assessed after each procedure or after the last RFA. Over a mean follow-up of 64 ± 51 months, VT-free survival was 37% at 1 year, 19% at 5 years, and 14% at 10 years. Ventricular tachycardia burden was significantly reduced after one procedure (23 vs. 11 VT episodes/year, P < 0.01) and after the last RFA (14 vs. 2 VT episodes/year, P < 0.01). Over a mean follow-up of 49 ± 52 months, clinical response after the last RFA (freedom from sudden cardiac death, VT requiring hospitalization, or heart transplantation) was 86% at 1 year, 69% at 5 years, and 60% at 10 years. Clinical response was associated with right ventricular dysfunction (RVD) and low numbers of mappable VT before the first RFA. Conclusion: RFA was predominantly targeted at the endocardial surface. Ventricular tachycardia recurrences were common, but few ARVC patients experienced major clinical events during follow-up. Further studies should investigate the benefit of extensive substrate ablation combined with endo-epicardial strategies.

Idiopathic epicardial ventricular tachycardia from the coronary venous system: From electrocardiographic recognition to appropriate therapy.

Idiopathic epicardial ventricular tachycardias (VTs) account for 9% of idiopathic VTs. The recognition of this entity is important, as a minimally invasive ablation procedure performed exclusively through the coronary sinus branches may be considered, avoiding the potential risks associated with access to the left ventricular endocardium, the aortic root, and the pericardial space. The electrocardiographic features and therapeutic management of this rare form of tachycardia are discussed.

Catheter ablation of epicardial ventricular tachycardia from the coronary venous system: Is endocardial mapping always required?

Endocardial mapping is typically considered as the first step of VT ablation procedures. Nevertheless, when the electrocardiogram is highly suggestive of an epicardial VT, a minimally invasive procedure performed exclusively via the coronary sinus might be considered. This straightforward approach avoids all potential complications associated with access to the left ventricular endocardium, the aortic root, and the pericardial space.

Impact of remote monitoring on reducing the burden of inappropriate shocks related to implantable cardioverter-defibrillator lead fractures: insights from a French single-centre registry.

AIMS: Lead fractures in implantable cardioverter-defibrillator (ICD) patients may cause inappropriate shocks (ISs). An early diagnosis is essential to prevent adverse clinical events. Implantable cardioverter-defibrillator remote monitoring (RM) permits prompt detection of lead fracture. Limited data define the impact of RM on ISs specifically related to lead fracture. We sought to compare the number of ISs related to lead fracture in patients with vs. without RM follow-up. METHODS AND RESULTS: We checked the registry of our institution and collected, between July 2007 and June 2014, 115 cases of right ventricular lead fractures. All relevant data were documented from patients' files, device-interrogation printouts and electronic records, and remote transmissions databases when applicable. We assessed the ISs that were related to lead fracture. The first study endpoint was the number of ISs per shocked patient. Among the 82 patients with conventional follow-up (CFU) and the 33 patients with RM, a first IS occurred to 32.9% (n = 27) and 30.3% (n = 10, P = 0.83) of the patients, respectively. Shocked patients in the RM group underwent significantly fewer ISs with a mean of 6 ± 2 shocks per patient [median of 3.5 shocks (2-8)] than those in the CFU group with a mean of 18 ± 5 shocks per patient [median of 10 shocks (5-22), P = 0.03]. CONCLUSION: Remote monitoring helps to reduce the burden of ISs related to ICD lead fractures.

Potential role of antitachycardia pacing alerts for the reduction of emergency presentations following shocks in patients with implantable cardioverter-defibrillators: implications for the implementation of remote monitoring.

AIMS: Despite increased use of remote monitoring (RM) to follow up implantable cardioverter-defibrillator (ICD) recipients, many patients still receive ICD shocks in the community and present to the emergency department. Our aim was to identify the best predictors of impending shock delivery that can be measured with an ICD and to identify the most appropriate activities to alert physicians to during RM follow-up. METHODS AND RESULTS: All patients presenting to our institution for ICD shock, from November 2011 to November 2014, were enrolled in this prospective study. Patient characteristics, investigation results, and details of electrical activities from ICD interrogation were recorded at presentation. Presentations were classified as potentially avoidable if activities from a list of set criteria were apparent more than 48 h before index shock. Univariate and multivariate analyses were then used to identify predictors of potentially avoidable shocks. In total, 109 emergency presentations were recorded in 90 patients (male: 85%; 57 ± 16 years; ischaemic cardiomyopathy: 49%; LVEF: 34 ± 13%; electrical storm: 40%), of which 26 (24%) were potentially avoidable. Antitachycardia pacing (ATP) episodes were the most important predictor of impending shock. Potentially avoidable shocks were preceded by more episodes of ATP than unavoidable shocks (13 [3-67] vs. 3 [0-10]; P < 0.001). Patients followed up with RM systems configured to generate alerts following ATP delivery experienced significantly less ICD shocks (24 vs. 16%, P < 0.01). CONCLUSION: Remote monitoring systems that generate alerts following ATP delivery could reduce emergency presentations for ICD shock by 24%, as ATP is a key predictor of impending shock delivery.

Decreased delivery of inappropriate shocks achieved by remote monitoring of ICD: a substudy of the ECOST trial.

INTRODUCTION: Inappropriate shocks remain a highly challenging complication of implantable cardioverter defibrillators (ICD). We examined whether automatic wireless remote monitoring (RM) of ICD, by providing early notifications of triggering events, lowers the incidence of inappropriate shocks. METHODS AND RESULTS: We studied 433 patients randomly assigned to RM (n = 221; active group) versus ambulatory follow-up (n = 212; control group). Patients in the active group were seen in the ambulatory department once a year, unless RM reported an event requiring an earlier ambulatory visit. Patients in the control group were seen in the ambulatory department every 6 months. The occurrence of first and further inappropriate shocks, and their causes in each group were compared. The characteristics of the study groups, including pharmaceutical regimens, were similar. Over a follow-up of 27 months, 5.0% of patients in the active group received ≥1 inappropriate shocks versus 10.4% in the control group (P = 0.03). A total of 28 inappropriate shocks were delivered in the active versus 283 in the control group. Shocks were triggered by supraventricular tachyarrhythmias (SVTA) in 48.5%, noise oversensing in 21.2%, T wave oversensing in 15.2%, and lead dysfunction in 15.2% of patients. The numbers of inappropriate shocks delivered per patient, triggered by SVTA and by lead dysfunction, were 74% and 98% lower, respectively, in the active than in the control group. CONCLUSION: RM was highly effective in the long-term prevention of inappropriate ICD shocks.

Pregnancy in women with an implantable cardioverter-defibrillator: is it safe?

AIMS: To describe obstetric/neonatal and cardiac outcomes for a cohort of women carrying implantable cardioverter-defibrillators (ICDs) during pregnancy. METHODS AND RESULTS: All women in routine follow-up at our institution for ICD implantation who became pregnant between 2006 and 2013 were included in this study. All ICDs were pre-pectoral devices with bipolar endocardial leads. Obstetric/neonatal and cardiac outcomes were assessed during pregnancy and post-partum. Twenty pregnancies were conceived by 12 women carrying ICD devices, 14 of which resulted in live births and none in maternal death. Seven of these women had structural cardiomyopathies and five had channelopathies. No device-related complications were recorded. Twelve shocks (nine transthoracic and three from ICDs) were experienced during pregnancy by two women, one of whom miscarried shortly afterwards at 4 weeks gestation. One stillbirth, three miscarriages and one termination were recorded for women with long QT syndrome, repaired tetralogy of Fallot and repaired Laubry-Pezzi syndrome, respectively. Intrauterine growth restriction, low birth weight, and neonatal hypoglycaemia were recorded in four, three, and five pregnancies, respectively. CONCLUSIONS: Pregnancy had no effect on ICD operation and no evidence was found to link ICD carriage with adverse pregnancy outcomes, although one miscarriage may have been induced by ICD shock therapy. A worsening of cardiac condition occurs in specific cardiac diseases and ß-blocker therapy should be continued for all women carrying ICDs in pregnancy as the benefits outweigh the risks of taking this medication.

Recurrences of Atrial Fibrillation Despite Durable Pulmonary Vein Isolation: The PARTY-PVI Study.

BACKGROUND: Recurrences of atrial fibrillation (AF) after pulmonary vein isolation (PVI) are mainly due to pulmonary vein reconnection. However, a growing number of patients have AF recurrences despite durable PVI. The optimal ablative strategy for these patients is unknown. We analyzed the impact of current ablation strategies in a large multicenter study. METHODS: Patients undergoing a redo ablation for AF and presenting durable PVI were included. The freedom from atrial arrhythmia after pulmonary vein-based, linear-based, electrogram-based, and trigger-based ablation strategies were compared. RESULTS: Between 2010 and 2020, 367 patients (67% men, 63±10 years, 44% paroxysmal) underwent a redo ablation for AF recurrences despite durable PVI at 39 centers. After durable PVI was confirmed, linear-based ablation was performed in 219 (60%) patients, electrogram-based ablation in 168 (45%) patients, trigger-based ablation in 101 (27%) patients, and pulmonary vein-based ablation in 56 (15%) patients. Seven patients (2%) did not undergo any additional ablation during the redo procedure. After 22±19 months of follow-up, 122 (33%) and 159 (43%) patients had a recurrence of atrial arrhythmia at 12 and 24 months, respectively. No significant difference in arrhythmia-free survival was observed between the different ablation strategies. Left atrial dilatation was the only independent factor associated with arrhythmia-free survival (HR, 1.59 [95% CI, 1.13-2.23]; P=0.006). CONCLUSIONS: In patients with recurrent AF despite durable PVI, no ablation strategy used alone or in combination during the redo procedure appears to be superior in improving arrhythmia-free survival. Left atrial size is a significant predictor of ablation outcome in this population.

Basal exit site of clinical ventricular tachycardia is an independent predictor of antitachycardia pacing failure in implantable cardioverter-defibrillators recipients.

BACKGROUND: Little is known about predictors of antitachycardia pacing (ATP) failure in implantable cardioverter defibrillator (ICD) recipients. Distance between the stimulation site and the ventricular tachycardia (VT) site of origin may critically affect ATP effectiveness. We hypothesized that ATP may be less effective in ICD patients who had basal VT than in those who had apical VT. METHODS: We reviewed data from 52 patients with sustained monomorphic VT and left ventricular disease referred for ICD implantation. ATP was delivered exclusively at the right ventricular apex. The clinical VTs site of origin (basal, midventricular, or apical) was determined in each patient, using 12-lead electrocardiogram. VTs episodes treated with ATP during the 1-year follow-up were studied. ATP success rate (%), defined as the ratio between the number of successful ATP sequences and the number of delivered ATP sequences, was determined in each patient. RESULTS: VT exit site was apical in 19 patients (36%), basal in 18 patients (35%), and midventricular in 15 patients (29%). In those 52 patients, 1,393 ATP sequences, delivered to treat 761 VT episodes, were analyzed. ATP success rate was found to be associated with the VT site of origin (median [interquartile range]): basal (33%[11-67]), midventricular (50%[37-100]), apical (100%[41-100]) (P = 0.027). Multivariate analysis identified basal VT site of origin as an independent predictor of ATP failure (P = 0.023). CONCLUSION: ATP is less effective in ICD patients who had basal VT than in those who had apical VT before ICD implantation.

Clopidogrel increases bleeding complications in patients undergoing heart rhythm device procedures.

BACKGROUND: Management of antiplatelet therapy at the time of device implantation remains controversial. This study aimed to assess the risk of bleeding complications in patients receiving clopidogrel at the time of cardiac device surgery. METHODS: We performed a retrospective case-control study. Between 2004 and 2010, 101 consecutive patients receiving clopidogrel underwent cardiac device surgery (pacemaker or implantable cardioverter-defibrillator implantation, and generator replacement) in our institution. Controls were 1:1 matched on age, sex, device, type of procedure, number of leads implanted, and venous approach (cephalic or subclavian). A significant bleeding complication was defined as pocket hematoma requiring surgical evacuation or prolonged hospitalization, hemothorax, pericardial effusion, or tamponade. RESULTS: Bleeding complications occurred more frequently in patients receiving clopidogrel at the time of device procedure: 11.9% versus 4.0% (P = 0.037; odds radio [OR] 3.27 [1.02-10.5]). Significant bleeding complications were noted in 12 patients (11.9%) receiving clopidogrel, including two patients with pericardial effusion and one patient with hemothorax. Four controls (4.0%) had bleeding complications (three pocket hematomas and one pericardial effusion). The single factor associated with increased bleeding complications in patients receiving clopidogrel was subclavian puncture (P = 0.008). In the entire cohort (n = 202), multivariate analysis identified two independent predictors of significant bleeding complications: clopidogrel treatment at the time of surgery (P = 0.03; OR 3.7 [1.1-12.6]) and subclavian venous puncture (P = 0.03; OR 3.44 [1.1-10.4]). CONCLUSIONS: Clopidogrel treatment at the time of heart rhythm device procedures is associated with an increased risk of significant bleeding complications. Subclavian puncture seems to strongly increase hemorrhagic complications in this setting.

Permanent junctional reciprocating tachycardia: a rare, but not to be missed, cause of cardiogenic shock in adults.

We report the case of a 64-year-old woman who was admitted for cardiogenic shock caused by a permanent junctional reciprocating tachycardia. If this incessant and drug-refractory form of tachycardia is a well-known cause of tachycardia-induced cardiomyopathies in infants, its occurrence during adulthood is extremely rare. Catheter ablation is the recommended treatment of this condition.

Current results of left ventricular assist device therapy in France: the ASSIST-ICD registry.

OBJECTIVES: Our goal was to provide a picture of left ventricular assist device (LVAD) activity in France between 2007 and 2016 based on the multicentric ASSIST-ICD registry. METHODS: We retrospectively collected 136 variables including in-hospital data, follow-up survival rates and adverse events from 671 LVAD recipients at 20 out of 24 LVAD implant centres in France. The average follow-up time was 1.2 years (standard deviation: 1.4); the total follow-up time was 807.5 patient-years. RESULTS: The included devices were the HeartMate II®, HeartWare LVAS® or Jarvik 2000®. The overall likelihood of being alive while on LVAD support or having a transplant (primary end point) at 1, 2, 3 and 5 years postimplantation was 65.2%, 59.7%, 55.9% and 47.7%, respectively, given a cumulative incidence of 29.2% of receiving a transplant at year 5. At implantation, 21.5% of patients were on extracorporeal life support. The overall rate of cardiogenic shock at implantation was 53%. The major complications were driveline infection (26.1%), pump pocket or cannula infection (12.6%), LVAD thrombosis (12.2%), ischaemic (12.8%) or haemorrhagic stroke (5.4%; all strokes 18.2%), non-cerebral haemorrhage (9.1%) and LVAD exchange (5.2%). The primary end point (survival) was stratified by age at surgery and by the type of device used, with inference from baseline profiles. The primary end point combined with an absence of complications (secondary end point) was also stratified by device type. CONCLUSIONS: The ASSIST-ICD registry provides a real-life picture of LVAD use in 20 of the 24 implant centres in France. Despite older average age and a higher proportion of patients chosen for destination therapy, survival rates improved compared to those in previous national registry results. This LVAD registry contrasts with other international registries because patients with implants have more severe disease, and the national policy for graft attribution is distinct. We recommend referring patients for LVAD earlier and suggest a discussion of the optimal timing of a transplant for bridged patients (more dismal results after the second year of support?).

Early Ventricular Arrhythmias After LVAD Implantation Is the Strongest Predictor of 30-Day Post-Operative Mortality.

OBJECTIVES: This study aimed to evaluate incidence, clinical significance, and predictors of early ventricular arrhythmias (VAs) in left ventricular assist device (LVAD) recipients. BACKGROUND: LVAD implantation is increasingly used in patients with end-stage heart failure. Early VAs may occur during the 30-day post-operative period, but many questions remain unanswered regarding their incidence and clinical impact. METHODS: This observational study was conducted in 19 centers between 2006 and 2016. Early VAs were defined as sustained ventricular tachycardia and/or ventricular fibrillation occurring <30 days post-LVAD implantation and requiring appropriate implantable cardioverter-defibrillator therapy, external electrical shock, or medical therapy. RESULTS: A total of 652 patients (median age: 59.8 years; left ventricular ejection fraction: 20.7 ± 7.4%; HeartMate 2: 72.8%; HeartWare: 19.5%; Jarvik 2000: 7.7%) were included in the analysis. Early VAs occurred in 162 patients (24.8%), most frequently during the first week after LVAD implantation. Multivariable analysis identified history of VAs prior to LVAD and any combined surgery with LVAD as 2 predictors of early VAs. The occurrence of early VAs with electrical storm was the strongest predictor of 30-day post-operative mortality, associated with a 7-fold increase of 30-day mortality. However, in patients discharged alive from hospital, occurrence of early VAs did not influence long-term survival. CONCLUSIONS: Early VAs are common after LVAD implantation and increase 30-day post-operative mortality, without affecting long-term survival. Further studies will be needed to analyze whether pre- or pre-operative ablation of VAs may improve post-operative outcomes. (Determination of Risk Factors of Ventricular Arrhythmias After Implantation of Continuous Flow Left Ventricular Assist Device With Continuous Flow Left Ventricular Assist Device [ASSIST-ICD]; NCT02873169).

Incidence, predictors, and clinical impact of electrical storm in patients with left ventricular assist devices: New insights from the ASSIST-ICD study.

BACKGROUND: Ventricular arrhythmias (VAs) can occur after continuous flow left ventricular assist device (LVAD) implantation as a single arrhythmic event or as electrical storm (ES) with multiple repetitive VA episodes. OBJECTIVE: We aimed at analyzing the incidence, predictors, and clinical impact of ES in LVAD recipients. METHODS: Patients analyzed were those included in the multicenter ASSIST-ICD observational study. ES was consensually defined as occurrence of ≥3 separate episodes of sustained VAs within a 24-hour interval. RESULTS: Of 652 patients with an LVAD, 61 (9%) presented ES during a median follow-up period of 9.1 (interquartile range [IQR] 2.5-22.1) months. The first ES occurred after 17 (IQR 4.0-56.2) days post LVAD implantation, most of them during the first month after the device implantation (63%). The incidence then tended to decrease during the initial years of follow-up and increased again after the third year post LVAD implantation. History of VAs before LVAD implantation and heart failure duration > 84 months were independent predictors of ES. The occurrence of ES was associated with an increased early mortality since 20 patients (33%) died within the first 2 weeks of ES. Twenty-two patients (36.1%) presented at least 1 recurrence of ES, occurring 43.0 (IQR 8.0-69.0) days after the initial ES. Patients experiencing ES had a significantly lower 1-year survival rate than did those free from ES (log-rank, P = .039). CONCLUSION: There is a significant incidence of ES in patients with an LVAD. The short-term mortality after ES is high, and one-third of patients will die within 15 days. Whether radiofrequency ablation of arrhythmias improves outcomes would require further studies.

Predictors and Clinical Impact of Late Ventricular Arrhythmias in Patients With Continuous-Flow Left Ventricular Assist Devices.

OBJECTIVES: This study aimed to evaluate the incidence, clinical impact, and predictors of late ventricular arrhythmias (VAs) in left ventricular assist device (LVAD) recipients aiming to clarify implantable cardioverter-defibrillator (ICD) indications. BACKGROUND: The arrhythmic risk and need for ICD in patients implanted with an LVAD are not very well known. METHODS: This observational study was conducted in 19 centers between 2006 and 2016. Late VAs were defined as sustained ventricular tachycardia or fibrillation occurring >30 days post-LVAD implantation, without acute reversible cause and requiring appropriate ICD therapy, external electrical shock, or medical therapy. RESULTS: Among 659 LVAD recipients, 494 (median 58.9 years of age; mean left ventricular ejection fraction 20.7 ± 7.4%; 73.1% HeartMate II, 18.6% HeartWare, 8.3% Jarvik 2000) were discharged alive from hospital and included in the final analysis. Late VAs occurred in 133 (26.9%) patients. Multivariable analysis identified 6 independent predictors of late VAs: VAs before LVAD implantation, atrial fibrillation before LVAD implantation, idiopathic etiology of the cardiomyopathy, heart failure duration >12 months, early VAs (<30 days post-LVAD), and no angiotensin-converting enzyme inhibitors during follow-up. The "VT-LVAD score" was created, identifying 4 risk groups: low (score 0 to 1), intermediate (score 2 to 4), high (score 5 to 6), and very high (score 7 to 10). The rates of VAs at 1 year were 0.0%, 8.0%, 31.0% and 55.0%, respectively. CONCLUSIONS: Late VAs are common after LVAD implantation. The VT-LVAD score may help to identify patients at risk of late VAs and guide ICD indications in previously nonimplanted patients. (Determination of Risk Factors of Ventricular Arrhythmias [VAs] after implantation of continuous flow left ventricular assist device with continuous flow left ventricular assist device [CF-LVAD] [ASSIST-ICD]; NCT02873169).