Incidence of Ventricular Arrhythmias in Patients on Long-term Support With a Continuous-flow Assist Device (HeartMate II)

Real-world data of patients affected by advanced heart failure treated with implantable cardioverter defibrillator and left ventricular assist device: Results of a multicenter observational study

BACKGROUND

Left ventricular assist device (L-VAD) implantation is increasingly used in patients with heart failure (HF) and most patients also have an implantable cardioverter defibrillator (ICD). Limited data are available on the incidence of ICD therapies and complications in this special setting. The aim of this study was to analyze the real-world incidence and predictors of ICD therapies, complications and interactions between ICD and L-VAD.

METHODS

We conducted a multicenter retrospective observational study in patients with advanced HF implanted with ICD and a continuous-flow L-VAD, followed-up in five advanced HF centers in Northern Italy.

RESULTS

A total of 234 patients (89.7% male, median age 59, 48.3% with ischemic etiology) were enrolled. After a median follow-up of 21 months, 66 patients (28.2%) experienced an appropriate ICD therapy, 22 patients (9.4%) an inappropriate ICD therapy, and 17 patients (7.3%) suffered from an interaction between ICD and L-VAD. The composite outcome of all ICD-related complications was reported in 41 patients (17.5%), and 121 (51.7%) experienced an L-VAD-related complication. At multivariable analysis, an active ventricular tachycardia (VT) zone and a prior ICD generator replacement were independent predictors of ICD therapies and of total ICD-related complications, respectively.

CONCLUSIONS

Real-world patients with both L-VAD and ICD experience a high rate of ICD therapies and complications. Our findings suggest the importance of tailoring device programming in order to minimize the incidence of unnecessary ICD therapies, thus sparing the need for ICD generator replacement, a procedure associated to a high risk of complications.

Left ventricular assist device in the presence of subcutaneous implantable cardioverter defibrillator: Data from a multicenter experience

BACKGROUND

Left ventricular assist devices (LVADs) are an increasingly used strategy for the management of patients with advanced heart failure (HF). Subcutaneous implantable cardioverter defibrillator (S-ICD) might be a viable alternative to conventional ICDs with a lower risk of short- and long-term of device-related complications and infections.The aim of this multicenter study was to evaluate the outcomes and management of S-ICD recipients who underwent LVAD implantation.

METHODS

The study population included patients with a preexisting S-ICD who underwent LVAD implantation for advanced HF despite optimal medical therapy.

RESULTS

The study population included 30 patients (25 male; median age 45 [38-52] years).The HeartMate III was the most common LVAD type. Median follow-up in the setting of concomitant use of S-ICDs and LVADs was 7 months (1-20).There were no reports of inability to interrogate S-ICD systems in this population. Electromagnetic interference (EMI) occurred in 21 (70%) patients. The primary sensing vector was the one most significantly involved in determining EMI. Twenty-seven patients (90%) remained eligible for S-ICD implantation with at least one optimal sensing vector. The remaining 3 patients (10%) were ineligible for S-ICD after attempts of reprogramming of sensing vectors. Six patients (20%) experienced inappropriate shocks (IS) due to EMI. Six patients (20%) experienced appropriate shocks. No S-ICD extraction because of need for antitachycardia pacing, ineffective therapy or infection was reported.

CONCLUSIONS

Concomitant use of LVAD and S-ICD is feasible in most patients. However, the potential risk of EMI oversensing, IS and undersensing in the post-operative period following LVAD implantation should be considered. Careful screening for EMI should be performed in all sensing vectors after LVAD implantation.

Managing ventricular arrhythmias and implantable cardiac defibrillator shocks after left ventricular assist device implantation

Continuous flow left ventricular assist devices (CF-LVADs) have been shown to reduce mortality and morbidity in patients with advanced heart failure with reduced ejection fraction. However, ventricular arrhythmias (VA) are common, are mostly secondary to underlying myocardial scar, and have a higher incidence in patients with pre-LVAD VA. Sustained VA is well tolerated in the LVAD patient but can result in implantable defibrillator (ICD) shocks, right ventricular failure, hospitalizations, and reduced quality of life. There is limited data regarding best practices for the medical management of VA as well as the role for procedural interventions in patients with uncontrolled VA and/or ICD shocks. Vast majority of CF-LVAD patients have a preexisting cardiovascular implantable electronic device (CIED) and ICD and/or cardiac resynchronization therapies are continued in many. Several questions, however, remain regarding the efficacy of ICD and CRT following CF-LVAD. Moreover, optimal CIED programming after CF-LVAD implantation. Therefore, the primary objective of this review article is to provide the most up-to-date evidence and to provide guidance on the clinical significance, pathogenesis, predictors, and management strategies for VA and ICD therapies in the CF-LVAD population. We also discuss knowledge gaps as well as areas for future research.

Ventricular Arrhythmias in Left Ventricular Assist Device Patients-Current Diagnostic and Therapeutic Considerations

Left ventricular assist devices (LVAD) are used in the treatment of advanced left ventricular heart failure. LVAD can serve as a bridge to orthotopic heart transplantation or as a destination therapy in cases where orthotopic heart transplantation is contraindicated. Ventricular arrhythmias are frequently observed in patients with LVAD. This problem is further compounded as a result of diagnostic difficulties arising from presently available electrocardiographic methods. Due to artifacts from LVAD-generated electromagnetic fields, it can be challenging to assess the origin of arrhythmias in standard ECG tracings. In this article, we will review and discuss common mechanisms, diagnostics methods, and therapeutic strategies for ventricular arrhythmia treatment, as well as numerous problems we face in LVAD implant patients.

Cardiac stereotactic radiation therapy for refractory ventricular arrhythmias in patients with left ventricular assist devices

Left ventricular assist device (LVAD) implantation is an established treatment for patients with advanced heart failure refractory to medical therapy. However, the incidence of ventricular arrhythmias (VAs) is high in this population, both in the acute and delayed phases after implantation. About one-third of patients implanted with an LVAD will experience sustained VAs, predisposing these patients to worse outcomes and complicating patient management. The combination of pre-existing myocardial substrate and complex electrical remodeling after LVAD implantation account for the high incidence of VAs observed in this population. LVAD patients presenting VAs refractory to antiarrhythmic therapy and catheter ablation procedures are not rare. In such patients, treatment options are extremely limited. Stereotactic body radiation therapy (SBRT) is a technique that delivers precise and high doses of radiation to highly defined targets, reducing exposure to adjacent normal tissue. Cardiac SBRT has recently emerged as a promising alternative with a growing number of case series reporting the effectiveness of the technique in reducing the VA burden in patients with arrhythmias refractory to conventional therapies. The safety profile of cardiac SBRT also appears favorable, even though the current clinical experience remains limited. The use of cardiac SBRT for the treatment of refractory VAs in patients implanted with an LVAD are even more scarce. This review summarizes the clinical experience of cardiac SBRT in LVAD patients and describes technical considerations related to the implementation of the SBRT procedure in the presence of an LVAD.

Management of Ventricular Arrhythmias in Heart Failure

PURPOSE OF REVIEW

Despite substantial progress in medical and device-based heart failure (HF) therapy, ventricular arrhythmias (VA) and sudden cardiac death (SCD) remain a major challenge. Here we review contemporary management of VA in the context of HF with one particular focus on recent advances in imaging and catheter ablation.

RECENT FINDINGS

Besides limited efficacy of antiarrhythmic drugs (AADs), their potentially life-threatening side effects are increasingly acknowledged. On the other hand, with tremendous advances in catheter technology, electroanatomical mapping, imaging, and understanding of arrhythmia mechanisms, catheter ablation has evolved into a safe, efficacious therapy. In fact, recent randomized trials support early catheter ablation, demonstrating superiority over AAD. Importantly, CMR imaging with gadolinium contrast has emerged as a central tool for the management of VA complicating HF: CMR is not only essential for an accurate diagnosis of the underlying entity and subsequent treatment decisions, but also improves risk stratification for SCD prevention and patient selection for ICD therapy. Finally, 3-dimensional characterization of arrhythmogenic substrate by CMR and imaging-guided ablation approaches substantially enhance procedural safety and efficacy. VA management in HF patients is highly complex and should be addressed in a multidisciplinary approach, preferably at specialized centers. While recent evidence supports early catheter ablation of VA, an impact on mortality remains to be demonstrated. Moreover, risk stratification for ICD therapy may have to be reconsidered, taking into account imaging, genetic testing, and other parameters beyond left ventricular function.

Meta-Analysis on the Impact of Ventricular Arrhythmias on Mortality in Patients With Continuous Flow Left Ventricular Assist Devices

Patients with continuous flow left ventricular assist devices (CFLVADs) have an increased risk of ventricular arrhythmias (VA), but the impact of VA on survival is unclear. A systematic search of electronic databases was conducted to identify studies that reported the impact of VA on all-cause mortality and right ventricular failure (RVF) in patients with CFLVAD. The Mantel-Haenszel method was used to calculate the 95% confidence interval (CI) and pooled risk ratio (RR) with a random-effects model. A total of 19 observational studies with 4,544 patients and a median follow-up of 18.5 months (interquartile range 11.5 to 26.4) were included. There was statistically significantly higher mortality in patients with any VA than in those with no VA after CFLVAD implantation (RR 1.33, 95% CI 1.01 to 1.75, p = 0.04, I² = 78%). On sensitivity analysis, after removing the largest study by Rehorn et al,¹⁰ the association between overall mortality and VA was lost, suggesting that these results should be interpreted with caution. Early VA developing within 30 days after implantation was associated with a higher risk of mortality (RR 1.37, 95% CI 1.15 to 1.63, p <0.01, I² = 52%), whereas late VA developing after 30 days after CFLVAD implantation was not associated with any significant difference in mortality (RR: 1.00; 95% CI: 0.80 to 1.24; p = 0.98, I² = 35%). In addition, there was a statistically significant higher risk of RVF in patients with VA than in those with no VA (RR 1.58, 95% CI 1.20 to 2.08, p <0.01, I² = 0%). In conclusion, in patients with CFLVAD, the development of any VA was associated with a 33% higher risk of all-cause mortality. Early VA developing within 30 days after implantation was significantly associated with a higher risk of mortality, whereas late VA was not associated with mortality. VA after left ventricular assist device was significantly associated with a higher risk of developing RVF.

Utilization of Implantable Cardioverter Defibrillators Among Patients with a Left Ventricular Assist Device: Insights From a National Database

The trends and predictors of implantable cardioverter defibrillator (ICD) use in patients with a durable left ventricular assist device (LVAD) remain uncertain. We used the National Inpatient Sample to identify hospitalizations between 2009 and 2018 in which patients received a new LVAD or had a pre-existing one. Procedure codes were then used to identify hospitalizations in which a new ICD was implanted. In 34,113 hospitalizations for new/replacement LVADs, an ICD was implanted in 1297 (3.8%). The rate of ICD implantation along with an LVAD declined from 2009-2018 (annual percent change: -23.2%; p-trend<0.001). Independent factors associated with concurrent ICD implantation in patients receiving LVAD were younger age, White (compared with Black) race, and in-hospital cardiac arrest. Concurrent ICD implantation was associated with a longer hospital stay (adjusted mean difference: 4.48 days) and higher inflation-adjusted costs (adjusted mean difference: $31,679), but lower in-hospital mortality rates (adjusted odds ratio: 0.29; p<0.001), compared with LVAD placement alone. Amongst 95,583 hospitalizations of patients with a pre-existing LVAD, an ICD was placed in 616 (0.64%). There was no change in the rate of ICD implantation from 2009-2018 in patients with a pre-existing LVAD (annual percent change: -10.34%; p=0.18).

Amiodarone Use and All-Cause Mortality in Patients With a Continuous-Flow Left Ventricular Assist Device

Background

Atrial and ventricular arrhythmias are commonly encountered in patients with advanced heart failure, with amiodarone being the most commonly used antiarrhythmic drug in continuous‐flow left ventricular assist device (CF‐LVAD) recipients. The purpose of this study was to assess the impact of amiodarone use on long‐term all‐cause mortality in ptients with a CF‐LVAD.

Methods and Results

A retrospective multicenter study of CF‐LVAD was conducted at 5 centers including all CF‐LVAD implants from 2007 to 2015. Patients were stratified based on pre–CF‐LVAD implant amiodarone use. Additional use of amiodarone after CF‐LVAD implantation was also evaluated. Primary outcome was all‐cause mortality during long‐term follow‐up. Kaplan‐Meier curves were used to assess survival outcomes. Multivariable Cox regression was used to identify predictors of outcomes. Propensity matching was done to address baseline differences. A total of 480 patients with a CF‐LVAD (aged 58±13 years, 81% men) were included. Of these, 170 (35.4%) were on chronic amiodarone therapy at the time of CF‐LVAD implant, and 310 (64.6%) were not on amiodarone. Rate of all‐cause mortality over the follow‐up period was 32.9% in the amiodarone group compared with 29.6% in those not on amiodarone (P=0.008). Similar results were noted in the propensity‐matched group (log‐rank, P=0.04). On multivariable Cox regression analysis, amiodarone use at baseline was independently associated with all‐cause mortality (hazard ratio, 1.68 [95% CI, 1.1–2.5]; P=0.01).

Conclusions

Amiodarone use was associated with significantly increased rates of all‐cause mortality in CF‐LVAD recipients. Earlier interventions for arrhythmias to avoid long‐term amiodarone exposure may improve long‐term outcomes in CF‐LVAD recipients and needs further study.

A review of new-onset ventricular arrhythmia after left ventricular assist device implantation

INTRODUCTION

Heart failure (HF) is a severe and terminal stage of various heart diseases. Left ventricular assist devices (LVADs) are relatively mature and have contributed to the treatment of end-stage HF. Ventricular arrhythmia (VA) is a common complication after LVAD implantation, including ventricular tachycardia and ventricular fibrillation, both of which may cause abnormal circulation in the body.

METHODS

A literature search was conducted in the PubMed database, "Ventricular Arrhythmia" OR "VA" OR "Arrhythmia" OR "Ventricular Tachycardia," OR "Ventricular Fibrillation" AND "LVAD" OR "Left Ventricular Assist Device" OR "Heart Assist Device" as either keywords or MeSH terms, the authors screened the titles and abstracts of the articles. Eventually, 12 original research articles were retrieved.

RESULTS

The 0.83 [95%CI: 0.77, 0.89] of patients were male. A whole of 53% [95%CI:0.25, 0.81] of VA patients had a history of atrial fibrillation and 61% [95%CI:0.52, 0.69] had a history of VA. 39% [95%CI:0.29, 0.49] of the participants had no prior history of VA and experienced new VA following CF-LVAD implantation. Following CF-LVAD implantation, 59% [95%CI:0.51, 0.67] of patients developed the early VA (VA ≤ 30 days). The 30-day mortality of patients was 4% [95%CI:0.01, 0.07]. And overall mortality was 28% [95%CI:0.15, 0.41] The reported incidence of VA after LVAD implantation is not identical in different medical centers and ranges from 20% to 60%. The mechanism of VA after LVAD implantation is summarized as primary cardiomyopathy-related, device mechanical stimulation, myocardial scarring, ventricular displacement, electrolyte regulation, and other processes.

CONCLUSIONS

A preoperative VA history is considered a predictor of VA following LVAD implantation in most studies. Multiple mechanisms and factors, such as prevention of "suction events", ablation, and ICD, should be considered for the prevention and treatment of postoperative VA in patients requiring long-term VAD treatment. This study provides a reference for the clinical application of LAVD and the prevention of postoperative VA after LVAD implantation. Future multicenter prospective studies with uniform patient follow-up are needed to screen for additional potential risk factors and predictors. These studies will help to define the incidence rate of VA after LAVD implantation. As a result, we provide guidance for the selection of preventive intervention.

Association Between Biventricular Pacing and Incidence of Ventricular Arrhythmias in the Early Post-Operative Period after Left Ventricular Assist Device Implantation

INTRODUCTION

Cardiac resynchronization therapy (CRT) and left ventricular assist devices (LVAD) improve outcomes in heart failure patients. Early ventricular arrhythmias (VA) are common after LVAD and are associated with increased mortality. The association between left ventricular pacing (LVP) with CRT and VAs in the early post-LVAD period remains unclear.

METHODS

This was a retrospective study of all patients undergoing LVAD implantation from 1/2016 - 12/2019. Patients were divided into those with CRT and active LVP (CRT-LVP) immediately post-LVAD implant versus those without CRT-LVP. ICD electrograms were reviewed and early VAs were defined as sustained VT/VF occurring within 30 days of LVAD implantation.

RESULTS

Of 186 included patients (mean age 53 years, 75% male, mean BMI 28), 72 had CRT devices, 63 of whom had LV pacing enabled after LVAD implant (CRT-LVP group). Patients with CRT-LVP were more likely to have VA in the early post-operative period (21% vs 4%; p=0.0001). All 9 patients with CRT in whom LVP was disabled had no early VA. Among those with early VA, patients with CRT-LVP were more likely to have monomorphic VT (77% vs 40%; p=0.07). In multiple logistic regression, CRT-LVP pacing remained an independent predictor of early VA after adjustment for history of VA and AF.

CONCLUSIONS

Patients with CRT-LVP after LVAD implant had a higher incidence of early VA (specifically monomorphic VT). Epicardial LV pacing may be proarrhythmic in the early post-operative period after LVAD. This article is protected by copyright. All rights reserved.

Impact of ultra-conservative ICD programming in patients with LVADs: Avoiding potentially unnecessary tachy-therapies

BACKGROUND

Patients with left ventricular assist devices (LVAD) often tolerate ventricular arrhythmias (VA). We aim to assess the frequency and outcomes of ICD therapies averted by ultraconservative ICD programming (UCP) in LVAD patients.

METHODS

This single center, retrospective cohort study included patients with LVADs and ICDs implanted from 2015 to 2019 that had UCP. The aim for UCP was to maximally delay VA treatments and maximize anti-tachycardia pacing (ATP) prior to ICD shocks. VA events were reviewed after UCP and evaluated under prior conservative programming to assess for potentially averted events (that would have resulted in either ATP or defibrillation with prior programming).

RESULTS

Fifty patients were included in the study with follow-up of median 16 ± 10.2 months after UCP. The median time from LVAD implantation to reprogramming was 7 days (IQR 5-9 days). Fourteen patients (28%) had potentially averted VA events that would have been treated with their prior ICD programming (82 total events, median two events per patient, IQR 1-10 events). Treated VA events occurred in 15 patients (30%). Eleven of the 14 patients with potentially averted VAs had treated events as well. Only one patient reported definitive symptoms of self-limited "dizziness" during a potentially averted event that did not result in hospitalization. No patients died of complications from or needed emergent care/hospitalization due a potentially averted VA.

CONCLUSIONS

UCP in LVAD patients likely prevented unnecessary VA treatments in many patients with minimal reported symptoms during these potentially averted events. Prospective studies are necessary to confirm these findings.

Active Implantable cardioverter-defibrillators in Continuous-flow Left Ventricular Assist Device Recipients

Introduction

Implantable cardioverter-defibrillator (ICD) in patients with heart failure with reduced ejection fraction reduces mortality secondary to malignant arrhythmias. Whether end-stage heart failure (HF) with continuous-flow left ventricular assist device (cf-LVAD) derive similar benefits remains controversial.

Methods

We performed a systematic literature review and meta-analysis of all published studies that examined the association between active ICDs and survival in advanced HF patients with cfLVAD. We searched PubMed, Medline, Embase, Ovid, and Cochrane for studies reporting the association between ICD and all-cause mortality in advanced HF patients with cfLVAD. Mantel-Haenszel risk ratio (RR) random-effects model was used to summarize data.

Results

Ten studies (9 retrospective and one prospective) with a total of 7,091 patients met inclusion criteria. There was no difference in all-cause mortality (RR 0.84, 95% CI 0.65-1.10, p=0.20, I² =62.40%), likelihood of survival to transplant (RR 1.07, 95% CI 0.98-1.17, p= 0.13, I² =0%), RV failure (RR 0.74, 95% CI 0.44-1.25, p = 0.26, I² =34%) between Active ICD and inactive/no ICD groups, respectively. Additionally, 27.5% received appropriate ICD shocks, while 9.5% received inappropriate ICD shocks. No significant difference was observed in terms of any complications between the two groups.

Conclusions

All-cause mortality, the likelihood of survival to transplant, and worsening RV failure were not significantly different between active ICD and inactive/no ICD in cf-LVAD recipients. A substantial number of patients received appropriate ICD shocks suggesting a high-arrhythmia burden. The risks and benefits of ICDs must be carefully considered in patients with cf-LVAD.

HFA of the ESC Position paper on the management of LVAD supported patients for the non LVAD specialist healthcare provider Part 1: Introduction and at the non-hospital settings in the community

The accepted use of left ventricular assist device (LVAD) technology as a good alternative for the treatment of patients with advanced heart failure together with the improved survival of the LVAD‐supported patients on the device and the scarcity of donor hearts has significantly increased the population of LVAD‐supported patients. The expected and non‐expected device‐related and patient–device interaction complications impose a significant burden on the medical system exceeding the capacity of the LVAD implanting centres. The ageing of the LVAD‐supported patients, mainly those supported with the ‘destination therapy’ indication, increases the risk for those patients to experience comorbidities common in the older population. The probability of an LVAD‐supported patient presenting with medical emergency to a local emergency department, internal, or surgical ward of a non‐LVAD implanting centre is increasing. The purpose of this trilogy is to supply the immediate tools needed by the non‐LVAD specialized physician: ambulance clinicians, emergency ward physicians, general cardiologists, internists, anaesthesiologists, and surgeons, to comply with the medical needs of this fast‐growing population of LVAD‐supported patients. The different issues discussed will follow the patient's pathway from the ambulance to the emergency department and from the emergency department to the internal or surgical wards and eventually to the discharge home from the hospital back to the general practitioner. In this first part of the trilogy on the management of LVAD‐supported patients for the non‐LVAD specialist healthcare provider, after the introduction on the assist devices technology in general, definitions and structured approach to the assessment of the LVAD‐supported patient in the ambulance and emergency department is presented including cardiopulmonary resuscitation for LVAD‐supported patients.

Guidance on the management of left ventricular assist device (LVAD) supported patients for the non-LVAD specialist healthcare provider: executive summary

The accepted use of left ventricular assist device (LVAD) technology as a good alternative for the treatment of patients with advanced heart failure together with the improved survival of patients on the device and the scarcity of donor hearts has significantly increased the population of LVAD supported patients. Device-related, and patient-device interaction complications impose a significant burden on the medical system exceeding the capacity of LVAD implanting centres. The probability of an LVAD supported patient presenting with medical emergency to a local ambulance team, emergency department medical team and internal or surgical wards in a non-LVAD implanting centre is increasing. The purpose of this paper is to supply the immediate tools needed by the non-LVAD specialized physician - ambulance clinicians, emergency ward physicians, general cardiologists, and internists - to comply with the medical needs of this fast-growing population of LVAD supported patients. The different issues discussed will follow the patient's pathway from the ambulance to the emergency department, and from the emergency department to the internal or surgical wards and eventually back to the general practitioner.

Ablation therapy for ventricular arrhythmias in patients with LVAD: Multiple faces of an electrophysiological challenge

Left ventricular assist device implantation is a recognized treatment option for patients with advanced heart failure refractory to medical therapy and can be used both as bridge to transplantation and as destination therapy. The risk of ventricular arrhythmias is common after left ventricular assist device implantation and is influenced by pre-, peri and post-operative determinants. The management of ventricular arrhythmias can be a challenge when they become refractory to medication or to device therapy and their impact on prognosis can be detrimental despite the mechanical support. In this setting, catheter ablation is being increasingly recognized as a feasible option for patients in which standard therapeutic strategies fail, but also with preventive purpose. Catheter ablation is being increasingly considered for the management of ventricular arrhythmias in patients with left ventricular assist device despite complex clinical and technical peculiarities due to the characteristics of the mechanical support. Much conflicting data exist regarding the predictors of success of the procedure and the rate of recurrence. In this review we discuss the latest evidences regarding catheter ablation of ventricular arrhythmias in this subset of patients, focusing on clinical characteristics, arrhythmia etiology, technical aspects and postprocedural features which must be considered by the electrophysiologist.

Surface mapping demonstrates compatibility of implantable loop monitor with a continuous-flow left ventricular assist device

Syncope in patients with continuous‐flow left ventricular assist device may be associated with arrhythmia and difficult to determine without an implantable cardioverter defibrillator. We present a patient with continuous‐flow left ventricular assist device, no implantable cardioverter defibrillator, and recurrent syncope. An implantable loop recorder was successfully implanted with surface mapping without noise interference.

Increased Rate of Pump Thrombosis and Cardioembolic Events Following Ventricular Tachycardia Ablation in Patients Supported With Left Ventricular Assist Devices

Ventricular arrhythmias are common following left ventricular assist device implantation (LVAD), and the effects of ventricular tachycardia (VT) ablation on thrombosis and embolic events are unknown. We aimed to assess LVAD thrombosis, stroke, and embolic event rates after VT ablation. Left ventricular assist device implantation patients from two academic centers who underwent endocardial VT ablation between 2009 and 2016 were compared to a control group with VT who were not ablated and followed for one year. The primary composite outcome was confirmed or suspected LVAD thrombosis, stroke, or other embolic event. Survival analysis was conducted with Kaplan-Meier curves, log-rank tests, and Cox regression. Forty-three LVAD patients underwent VT ablation, and 73 LVAD patients had VT but were not ablated. Patients who were ablated were more likely have VT prior to LVAD (p = 0.04), monomorphic VT (p < 0.01), and to be on antiarrhythmics (p < 0.01). Fifty-eight percent of the patients in the ablation group experienced the primary composite outcome (11% had confirmed device thrombosis [DT], 41% suspected DT, 39% had a stroke or embolic event) compared to 30% in the control group (12% with confirmed DT, 11% with suspected DT, 14% with stroke or embolic event) (p = 0.002). In multivariable regression, ablation was an independent predictor of the primary composite outcome (hazard ratios, 2.24; 95% confidence interval, 1.09-4.61; p = 0.03). Patients with LVADs referred for endocardial VT ablation had elevated rates of DT and embolic events.

Cardiac Emergencies in Patients with Left Ventricular Assist Devices

Continuous-flow left ventricular assist devices are frequently used for management of patients with advanced heart failure with reduced ejection fraction. Although technologic advancements have contributed to improved outcomes, several complications arise over time. These complications result from several factors, including medication effects, physiologic responses to chronic exposure to circulatory support that is minimally/entirely nonpulsatile, and dysfunction of the device itself. Clinical presentation can range from chronic and indolent to acute, life-threatening emergencies. Several areas of uncertainty exist regarding best practices for managing complications; however, growing awareness has led to development of new guidelines to reduce risk and improve outcomes.

Ventricular arrhythmias following continuous-flow left ventricular assist device implantation: A systematic review

Ventricular arrhythmias (VA) are not uncommon after continuous-flow left ventricular assist device (CF-LVAD) implantation. In this systematic review, we sought to identify the patterns of VA that occurred following CF-LVAD implantation and evaluate their outcomes. An electronic search was performed to identify all articles reporting the development of VA following CF-LVAD implantation. VA was defined as any episode of ventricular fibrillation (VF) or sustained (>30 seconds) ventricular tachycardia (VT). Eleven studies were pooled for the analysis that included 393 CF-LVAD patients with VA. The mean patient age was 57 years [95%CI: 54; 61] and 82% [95%CI: 73; 88] were male. Overall, 37% [95%CI: 19; 60] of patients experienced a new onset VA after CF-LVAD implantation, while 60% [95%CI: 51; 69] of patients had a prior history of VA. Overall, 88% of patients [95%CI: 78; 94] were supported on HeartMate II CF-LVAD, 6% [95%CI: 3; 14] on HeartWare HVAD, and 6% [95%CI: 2; 13] on other CF-LVADs. VA was symptomatic in 47% [95%CI: 28; 68] of patients and in 50% [95%CI: 37; 52], early VA (<30 days from CF-LVAD) was observed. The 30-day mortality rate was 7% [95%CI: 5; 11]. Mean follow-up was 22.9 months [95%CI: 4.8; 40.8], during which 27% [95%CI: 17; 39] of patients underwent heart transplantation. In conclusion, approximately a third of patients had new VA following CF-LVAD placement. VA in CF-LVAD patients is often symptomatic, necessitates treatment, and carries a worse prognosis.

Ventricular arrhythmias in patients with biventricular assist devices

PURPOSE

Ventricular arrhythmias (VAs) are common in patients after left ventricular assist device (LVAD) implant and are associated with worse outcomes. However, the prevalence and impact of VA in patients with durable biventricular assist device (BIVAD) is unknown. We performed a retrospective cohort study of patients with BIVADs to evaluate the prevalence of VA and their clinical outcomes.

METHODS

Consecutive patients who received a BIVAD between June 2014 and July 2017 at our medical center were included. The prevalence of VA, defined as sustained ventricular tachycardia or fibrillation requiring defibrillation or ICD therapy, was compared between BIVAD patients and a propensity-matched population of patients with LVAD from our center. The occurrence of adverse clinical events was compared between BIVAD patients with and without VA.

RESULTS

Of the 13 patients with BIVADs, 6 patients (46%) experienced clinically significant VA, similar to a propensity-matched LVAD population (38%, p = 1.00). There were no differences in baseline characteristics between the two cohorts, except patients in the non-VA group who had worse hemodynamics (mitral regurgitation and right-sided indices), had less history of VA, and were younger. BIVAD patients with VA had a higher incidence of major bleeding (MR 3.05 (1.07-8.66), p = 0.036) and worse composite outcomes (log-rank test, p = 0.046). The presence of VA was associated with worse outcomes in both LVAD and BIVAD groups.

CONCLUSIONS

Ventricular arrhythmias are common in patients with BIVADs and are associated with worse outcomes. Future work should assess whether therapies such as ablation improve the outcome of BIVAD patients with VA.

Ventricular Arrhythmias in Patients With Left Ventricular Assist Device (LVAD)

PURPOSE OF REVIEW

Left ventricular assist device (LVAD) implantation is a well-known treatment option for patients with advanced heart failure refractory to medical therapy and is recognized both as bridge to transplant and a destination therapy. The risk of ventricular arrhythmias (VAs) is common after LVAD implantation. We review the pathophysiology and recent advances in the management of VA in LVAD patients.

RECENT FINDINGS

VAs are most likely to occur in the early post-operative periods after LVAD implantation and a prior history of VA is the most important risk factor. Post-LVAD VAs are usually well tolerated with less morbidity and decreased risk of sudden cardiac death. However, risk of right heart failure in the setting of persistent VAs is being increasingly recognized. The mechanisms of post-LVAD VAs may vary depending on the time from LVAD implantation. Electrical remodeling may play an important role in the immediate post-implant phase. Preexisting myocardial scar and to a lesser extent mechanical irritation from the LVAD cannula are important in the later phases. Most LVAD patients have a previously placed implantable cardioverter-defibrillator (ICD). The benefit of implanting a new ICD in LVAD patients is unknown and should be individualized. For ICD programming, a conservative strategy with higher detection zones and prolonged time to detection is usually recommended aiming to minimize ICD shocks. More aggressive programming is appropriate if the VA results in hemodynamic instability. Antiarrhythmic drugs including amiodarone, mexiletine, and beta blockers are usually the first-line therapy for VAs. Catheter ablation has been shown to be safe and effective in LVAD recipients with recurrent VAs not responsive to antiarrhythmic drugs. LVAD-related VA is most frequently reentrant secondary to myocardial scar and usually well tolerated. Management options include antiarrhythmic drugs and catheter ablation.

Atrial Fibrillation Is Associated with Recurrent Ventricular Arrhythmias After LVAD Implant: Incidence and Impact in a Consecutive Series

This study examined left-ventricular assist device (LVAD) patients with pre-LVAD ventricular arrhythmias (VAs) to determine the rate of recurrent post-LVAD VAs and the impact of pre-LVAD atrial fibrillation (AF) on recurrent post-LVAD VAs. Medical records of 195 consecutive LVAD patients were reviewed. Descriptive statistics were generated and Cox proportional hazard models were used to assess the association of clinical variables with the time to recurrent VA. Forty-seven percent of 195 CHF patients who received LVAD-manifested significant VAs prior to LVAD implant (82% Heartmate II, 14% HVAD, 4% other; median follow-up = 17 months), 41% of whom manifested recurrent post-LVAD VAs. Pre-LVAD AF was associated with recurrent VAs (hazard ratio = 3.73; 95% CI 1.33, 10.48; p = 0.012). Recurrent VAs were associated with increased mortality (hazard ratio = 3.06; 95% CI 1.17, 7.98; p = 0.023). A history of AF is prevalent in over half of LVAD patients with recurrent VAs and is associated with time to recurrence of VA.

Mapping and Ablation of Ventricle Arrhythmia in Patients with Left Ventricular Assist Devices

Ventricular arrhythmias (VA) constitute well-known problems in patients with left ventricular assist devices (LVADs), with incidence ranging from 18% to as high as 52%. Catheter ablation has become a common therapeutic intervention to treat drug-refractory VA, particularly with the increase and more widespread use of durable LVADs to bridge patients to transplantation or as destination therapy. In this article, we focus on etiology, mechanisms, periprocedural management, and mapping and ablation techniques in patients with LVADs and VA.

ICD shocks in LVAD patients are not associated with increased subsequent mortality risk

BACKGROUND

Implantable cardioverter-defibrillator (ICD) shocks are associated with increased mortality risk in heart failure patients. Whether ICD shocks are associated with mortality in continuous flow LVAD (CF-LVAD) patients is unknown. We studied the relationship of ICD shocks and ventricular arrhythmias (VAs) to morbidity and mortality in CF-LVAD-supported patients in our institution.

METHODS

Single-center, retrospective study of prospectively collected ICD and LVAD databases. We analyzed data on VA which received ICD therapy in patients who underwent CF-LVAD implantation at Hartford Hospital between 2008 and 2018.

RESULTS

A total of 157 patients were studied. During a median follow-up of 10 months (interquartile range 5-20 months), 48 patients (30.6%) experienced post-LVAD sustained VA. Thirty patients (19.1%) had appropriate shocks for VA and 5 patients (3.1%) had inappropriate shocks. Shocks for any arrhythmia were not associated with an increased risk of death (OR 0.836, 95% CI 0.224-3.115, p = 0.789). Neither post-LVAD VA nor the rate of VA was associated with an increased mortality risk (OR 0.662 [0.329-1.334], p = 0.248; OR 1.001 [0.989-1.014], p = 0.817, respectively). Cox multivariate regression analysis revealed pre-LVAD VA as a significant predictor of VA post LVAD implantation (OR 3.284 [1.584-6.808], p = 0.001). Symptoms with VA occurred in 22 (45.8%) patients, ranging from palpitations to near syncope/syncope. None of the variables including the rate of VA was associated with death or symptoms.

CONCLUSIONS

VAs are common in CF-LVAD patients and occur with higher frequency in those with pre-LVAD VA and frequently cause symptoms. Neither VA nor ICD shocks are associated with mortality risk.

Cardiac implantable electronic devices with a defibrillator component and all-cause mortality in left ventricular assist device carriers: results from the PCHF-VAD registry

AIMS

To compare characteristics of left ventricular assist device (LVAD) recipients receiving a cardiac implantable electronic device (CIED) with a defibrillator component (implantable cardioverter-defibrillator and cardiac resynchronization therapy with defibrillation, CIED-D) vs. those without one, and to assess whether carrying such a device contiguously with an LVAD is associated with outcomes.

METHODS AND RESULTS

Overall, 448 patients were analysed (mean age 52 ± 13 years, 82% male) in the multicentre European PCHF-VAD registry. To account for all active CIED-Ds during ongoing LVAD treatment, outcome analyses were performed by a time-varying analysis with active CIED-D status post-LVAD as the time-varying covariate. At the time of LVAD implantation, 235 patients (52%) had an active CIED-D. Median time on LVAD support was 1.1 years (interquartile range 0.5-2.0 years). A reduction of 36% in the risk of all-cause mortality was observed in patients with an active CIED-D [hazard ratio (HR) 0.64, 95% confidence interval (CI) 0.46-0.91; P = 0.012), increasing to 41% after adjustment for baseline covariates (HR 0.59, 95% CI 0.40-0.87; P = 0.008) and 39% after propensity score adjustment (HR 0.61, 95% CI 0.39-0.94; P = 0.027). Other than CIED-D, age, LVAD implant as redo surgery, number of ventricular arrhythmia episodes and use of vasopressors pre-LVAD were remaining significant risk factors of all-cause mortality. Incident ventricular arrhythmias post-LVAD portended a 2.4-fold and 2.6-fold increased risk of all-cause and cardiovascular death, respectively; carrying an active CIED-D remained associated with a 47% and 43% reduction in these events, respectively.

CONCLUSIONS

In an analysis accounting for all active CIED-Ds, including those implanted during LVAD support, carrying such a device was associated with significantly better survival during LVAD support.

Cardiac Implantable Electronic Devices in Patients With Left Ventricular Assist Systems

Recent progress and evolution in device engineering, surgical implantation practices, and periprocedural management have advanced the promise of durable support with left ventricular assist systems (LVAS) in patients with stage D heart failure. With greater uptake of LVAS globally, a growing population of LVAS recipients have pre-existing cardiac implantable electronic devices (CIEDs). Strategies for optimal clinical management of CIEDs in patients with durable LVAS are evolving, and clinicians will increasingly face complex decisions regarding implantation, programming, deactivation, and removal of CIEDs. Traditional decision-making pathways for CIEDs may not apply to LVAS-supported patients, as few patients die of arrhythmic causes and many arrhythmias may be well tolerated. Given limited data, treatment decisions must be individualized and made collaboratively among electrophysiologists, advanced heart failure specialists, and patients and their caregivers. Large, prospective, well-conducted studies are needed to better understand the contemporary utility of CIEDs in patients with newer-generation LVAS.

Device Therapy and Arrhythmia Management in Left Ventricular Assist Device Recipients: A Scientific Statement From the American Heart Association

Left ventricular assist devices (LVADs) are an increasingly used strategy for the management of patients with advanced heart failure with reduced ejection fraction. Although these devices effectively improve survival, atrial and ventricular arrhythmias are common, predispose these patients to additional risk, and complicate patient management. However, there is no consensus on best practices for the medical management of these arrhythmias or on the optimal timing for procedural interventions in patients with refractory arrhythmias. Although the vast majority of these patients have preexisting cardiovascular implantable electronic devices or cardiac resynchronization therapy, given the natural history of heart failure, it is common practice to maintain cardiovascular implantable electronic device detection and therapies after LVAD implantation. Available data, however, are conflicting on the efficacy of and optimal device programming after LVAD implantation. Therefore, the primary objective of this scientific statement is to review the available evidence and to provide guidance on the management of atrial and ventricular arrhythmias in this unique patient population, as well as procedural interventions and cardiovascular implantable electronic device and cardiac resynchronization therapy programming strategies, on the basis of a comprehensive literature review by electrophysiologists, heart failure cardiologists, cardiac surgeons, and cardiovascular nurse specialists with expertise in managing these patients. The structure and design of commercially available LVADs are briefly reviewed, as well as clinical indications for device implantation. The relevant physiological effects of long-term exposure to continuous-flow circulatory support are highlighted, as well as the mechanisms and clinical significance of arrhythmias in the setting of LVAD support.

Implantable cardioverter-defibrillators and survival in advanced heart failure patients with continuous-flow left ventricular assist devices: a systematic review and meta-analysis

Aims

Implantable cardioverter-defibrillators (ICDs) implantation in heart failure (HF) patients with reduced ejection fraction improves survival by reducing mortality secondary to arrhythmic events. Whether advanced HF patients treated with continuous-flow left ventricular assist devices (CF-LVADs) derive similar benefit is controversial.

Methods and results

We searched PubMed, Cochrane Central Register of Controlled Trials, Embase, and Scopus from inception through November 2018 for studies examining the association between ICD implantation and all-cause mortality in patients with advanced HF and CF-LVADs. Analyses were performed using a random-effects model. Hazard ratios (HRs) were calculated with 95% confidence intervals (CIs). Heterogeneity and publication bias were formally assessed, using I2 and funnel plots, respectively. Eight observational studies with a total of 6416 patients (ICD group = 3450, no ICD group = 2966) met inclusion criteria. The majority of patients (84.6%) came from the two largest observational studies. There was no difference in mortality in the ICD and no ICD groups (HR 0.96, 95% CI 0.73–1.27, P = 0.79, I2 = 42%), and ICD implantation post-CF-LVAD was not associated with an improvement in mortality (HR 0.87, 95% CI 0.48–1.57, P = 0.64, I2 = 0%). Additionally, there was no significant difference in the likelihood of transplantation (HR 1.10, 95% CI 0.93–1.30, P = 0.28, I2 = 26%) or non-mortality adverse events between the two groups.

Conclusion

Implantable cardioverter-defibrillator use was not associated with improved survival in advanced HF patients with CF-LVADs. These findings underscore the need to formally study the efficacy of ICDs in this population in a dedicated randomized controlled study.

Feasibility and utility of intraoperative epicardial scar characterization during left ventricular assist device implantation

INTRODUCTION

Ventricular arrhythmias (VA) after left ventricular assist device (LVAD) placement are associated with increased morbidity and mortality. We sought to assess epicardial voltage characteristics at the time of LVAD implantation and investigate relationships between scar burden and postimplant VA.

METHODS AND RESULTS

Consecutive patients underwent open chest epicardial electroanatomic mapping immediately before LVAD implantation. Areas of low voltage and sites with local abnormal potentials were identified. Patients were followed prospectively for postimplant VA and clinical outcomes. Between 2015 and 2017, 36 patients underwent high-density intraoperative epicardial voltage mapping; 15 had complete maps suitable for analysis. Mapping required a median of 11.8 (interquartile range [IQR], 8.5-12.7) minutes, with a median of 2650 (IQR, 2139-3191) points sampled per patient. Over a median follow-up of 311 (IQR, 168-469) postoperative days, four patients (27%) experienced sustained VA. Patients with postimplant VA were more likely to have had preimplant implantable cardioverter defibrillator shocks (100% vs 27%; P = 0.03), ventricular tachycardia storm (75% vs 9%; P = 0.03), and lower ejection fraction (13.5 vs 19.0%, P = 0.05). Patients with postimplant VA also had a significantly higher burden of epicardial low bipolar voltage points: 55.4% vs 24.9% of points were less than 0.5 mV (P = 0.01), and 88.9% vs 63.7% of points less than 1.5 mV (P = 0.004).

CONCLUSIONS

Intraoperative high-density epicardial mapping during LVAD implantation is safe and efficient, facilitating characterization of a potentially arrhythmogenic substrate. An increased burden of the epicardial scar may be associated with a higher incidence of postimplant VA. The role of empiric intraoperative epicardial ablation to mitigate risk of postimplant VA requires further study.

Cardiac Resynchronization Therapy and Clinical Outcomes in Continuous Flow Left Ventricular Assist Device Recipients

Background

Many patients with heart failure continue cardiac resynchronization therapy (CRT) after continuous flow left ventricular assist device (CF‐LVAD) implant. We report the first multicenter study to assess the impact of CRT on clinical outcomes in CF‐LVAD patients.

Methods and Results

Analysis was performed on 488 patients (58±13 years, 81% male) with an implantable cardioverter defibrillator (ICD) (n=223) or CRT‐D (n=265) who underwent CF‐LVAD implantation at 5 centers from 2007 to 2015. Effects of CRT on mortality, hospitalizations, and ventricular arrhythmia incidence were compared against CF‐LVAD patients with an ICD alone. Baseline differences were noted between the 2 groups in age (60±12 versus 55±14, P<0.001) and QRS duration (159±29 versus 126±34, P=0.001). Median biventricular pacing in the CRT group was 96%. During a median follow‐up of 478 days, Kaplan–Meier analysis showed no difference in survival between groups (log rank P=0.28). Multivariate Cox regression demonstrated no survival benefit with type of device (ICD versus CRT‐D; P=0.16), whereas use of amiodarone was associated with increased mortality (hazard ratio 1.77, 95% confidence interval 1.1–2.8, P=0.01). No differences were noted between CRT and ICD groups in all‐cause (P=0.06) and heart failure (P=0.9) hospitalizations, ventricular arrhythmia incidence (43% versus 39%, P=0.3), or ICD shocks (35% versus 29%, P=0.2). During follow‐up, 69 (26%) patients underwent pulse generator replacement in the CRT‐D group compared with 36 (15.5%) in the ICD group (P=0.003).

Conclusions

In this large, multicenter CF‐LVAD cohort, continued CRT was not associated with improved survival, hospitalizations, incidence of ventricular arrhythmia and ICD therapies, and was related to a significantly higher number of pulse generator changes.

Clinical Implications of Physiologic Flow Adjustment in Continuous-Flow Left Ventricular Assist Devices

There is increasing evidence for successful management of end-stage heart failure with continuous-flow left ventricular assist device (CF-LVAD) technology. However, passive flow adjustment at fixed CF-LVAD speed is susceptible to flow balancing issues as well as adverse hemodynamic effects relating to the diminished arterial pulse pressure and flow. With current therapy, flow cannot be adjusted with changes in venous return, which can vary significantly with volume status. This limits the performance and safety of CF-LVAD. Active flow adjustment strategies have been proposed to improve the synchrony between the pump and the native cardiovascular system, mimicking the Frank-Starling mechanism of the heart. These flow adjustment strategies include modulation by CF-LVAD pump speed by synchrony and maintenance of constant flow or constant pressure head, or a combination of these variables. However, none of these adjustment strategies have evolved sufficiently to gain widespread attention. Herein we review the current challenges and future directions of CF-LVAD therapy and sensor technology focusing on the development of a physiologic, long-term active flow adjustment strategy for CF-LVADs.

Electrical storm in the early phase of HeartMate® II device implantation: Incidence, risk factors and prognosis

BACKGROUND

Ventricular arrhythmia is common after left ventricular assist device (LVAD) implantation, especially in the early postoperative phase (<30 days).

AIM

To identify the incidence of and risk factors for electrical storm (ES) occurring within 30 days of HeartMate^® II implantation.

METHODS

We reviewed data from all consecutive patients undergoing HeartMate^® II device implantation at our institution from January 2008 to December 2014. Patient demographic data, pharmacotherapies and outcomes were collected. The primary endpoint was occurrence of early ES (within 30 days of surgery), defined as three or more separate episodes of sustained ventricular arrhythmia within a 24-hour interval, requiring appropriate therapy.

RESULTS

Forty-three patients (mean age 56.7±11.2 years; 39 men) were included. At HeartMate^® II implantation, mean left ventricular ejection fraction was 20±5%, 32 (74.4%) patients had ischaemic cardiomyopathy and 31 (72.1%) were implanted with an indication of bridge to cardiac transplantation. During follow-up, 12 (27.9%) patients experienced early ES after HeartMate^® II implantation (median delay 9.1±7.8 days). Early ES was more frequent in larger patients (body surface area 1.99 vs 1.81 m²; P<0.01), tended to be associated with previous sustained ventricular tachycardia (50.0% vs 22.6%; P=0.08), previous implantable cardioverter-defibrillator implantation (66.7% vs 38.7%; P=0.09), discontinuation of long-term beta-blocker therapy (75.0% vs 45.2%; P=0.08), weaning of adrenergic drugs after the third day (66.7% vs 35.5%; P=0.06) and the use of extracorporeal life support (50% vs 22.6%; P=0.079), but was not associated with the cardiomyopathy aetiology or the indication for assistance. Catheter ventricular tachycardia ablation was performed in six (14.0%) patients. Early ES was associated with a significantly higher all-cause mortality rate at the 30th day (33.3% vs 6.5%; P=0.02).

CONCLUSION

ES is a common and pejorative feature in the early postoperative period.

Usefulness of Speckle Tracking Strain Echocardiography for Assessment of Risk of Ventricular Arrhythmias After Placement of a Left Ventricular Assist Device

Patients with continuous-flow left ventricular assist devices (LVADs) are at elevated risk of developing ventricular arrhythmias (VA), which can result in right ventricular dysfunction and abnormal LVAD function. Predictors of postoperative VA after LVAD placement are unclear. We hypothesized that global left ventricular circumferential strain (LVCS), a marker of transmural impairment in myocardial function, would independently predict postoperative VA in patients who underwent LVAD implantation. We studied 98 consecutive patients (57 ± 11 years, 83% men) who underwent HeartMate II axial flow LVAD placement. Speckle tracking-derived global circumferential strain was assessed from mid-left ventricular short-axis images. The primary composite end point was defined as any ventricular tachycardia that required intervention (anti-arrhythmic medication, cardioversion, implantable cardioverter defibrillator placement, implantable cardioverter defibrillator shock) or any ventricular fibrillation. A total of 33 patients (34%) experienced the primary end point (median follow-up: 7 months). Reduced LVCS was statistically significantly related to the primary end point (hazard ratio 1.77, 95% confidence interval 1.09 to 2.87 per 1 standard deviation reduction in LVCS, p = 0.02). LVCS above a cut-off value of -9.7% was associated with significantly reduced arrhythmia-free survival (log-rank p = 0.001). In conclusion, global LVCS is an independent predictor of ventricular arrhythmias after LVAD placement.

Arrhythmias in Patients with Cardiac Implantable Electrical Devices after Implantation of a Left Ventricular Assist Device

Utilization of continuous-flow left ventricular assist devices (CF-LVADs) for advanced heart failure is increasing, and the role of cardiac implantable electrical devices (CIED) is unclear. Prior studies of the incidence of arrhythmias and shocks are frequently limited by ascertainment. One hundred and seventy-eight patients were examined with a previous CIED who were implanted with a CF-LVAD. Medical history, medications, and CIED data from device interrogations were gathered. A cardiac surgery control group (n = 38) was obtained to control for surgical factors. Several clinically significant events increased after LVAD implantation: treated-zone ventricular arrhythmias (VA; p < 0.01), monitored-zone VA (p < 0.01), antitachycardia pacing (ATP)-terminated episodes (p < 0.01), and shocks (p = 0.01), although administered shocks later decreased (p < 0.01). Presence of a preimplant VA was associated with postoperative VA (odds ratio [OR]: 4.31; confidence interval [CI]: 1.5-12.3, p < 0.01). Relative to cardiac surgery, LVAD patients experienced more perioperative events (i.e., monitored VAs and shocks, p < 0.01 and p = 0.04). Neither implantable cardioverter defibrillator (ICD) shocks before implant nor early or late postimplant arrhythmias or shocks predicted survival (p = 0.07, p = 0.55, and p = 0.55). Our experience demonstrates time-dependent effects on clinically significant arrhythmias after LVAD implantation, including evidence that early LVAD-related arrhythmias may be caused by the unique arrhythmogenic effects of VAD implant.

Ventricular Tachycardia with ICD Shocks: When to Medicate and When to Ablate

PURPOSE OF REVIEW

Ventricular tachycardia occurrence in implantable cardioverter defibrillator (ICD) patients may result in shock delivery and is associated with increased morbidity and mortality. In addition, shocks may have deleterious mechanical and psychological effects. Prevention of ventricular tachycardia (VT) recurrence with the use of antiarrhythmic drugs or catheter ablation may be warranted. Antiarrhythmic drugs are limited by incomplete efficacy and an unfavorable adverse effect profile. Catheter ablation can be effective but acute complications and long-term VT recurrence risk necessitating repeat ablation should be recognized. A shared clinical decision process accounting for patients' cardiac status, comorbidities, and goals of care is often required.

RECENT FINDINGS

There are four published randomized trials of catheter ablation for sustained monomorphic VT (SMVT) in the setting of ischemic heart disease; there are no randomized studies for non-ischemic ventricular substrates. The most recent trial is the VANISH trial which randomly allocated patients with ICD, prior infarction, and SMVT despite first-line antiarrhythmic drug therapy to catheter ablation or more aggressive antiarrhythmic drug therapy. During 28 months of follow-up, catheter ablation resulted in a 28% relative risk reduction in the composite endpoint of death, VT storm, and appropriate ICD shock (p = 0.04). In a subgroup analysis, patients having VT despite amiodarone had better outcomes with ablation as compared to increasing amiodarone dose or adding mexiletine. There is evidence for the effectiveness of both catheter ablation and antiarrhythmic drug therapy for patients with myocardial infarction, an implantable defibrillator, and VT. If sotalol is ineffective in suppressing VT, either catheter ablation or initiation of amiodarone is a reasonable option. If VT occurs despite amiodarone therapy, there is evidence that catheter ablation is superior to administration of more aggressive antiarrhythmic drug therapy. Early catheter ablation may be appropriate in some clinical situations such as patients presenting with relatively slow VT below ICD detection, electrical storms, hemodynamically stable VT, or in very selected patients with left ventricular assist devices. The optimal first-line suppressive therapy for VT, after ICD implantation and appropriate programming, remains to be determined. Thus far, there has not been a randomized controlled trial to compare catheter ablation to antiarrhythmic drug therapy as a first-line treatment; the VANISH-2 study has been initiated as a pilot to examine this question.

Asymptomatic Sustained Polymorphic Ventricular Tachycardia in a Patient with a Left Ventricular Assist Device: Case Report and what the Emergency Physician Should Know

BACKGROUND

Left ventricular assist devices (LVADs) are a viable treatment option for patients with end-stage heart failure. LVADs can improve survival, quality of life, and functional status. The indications for LVAD placement to support left ventricular function are temporary support, a bridge to transplantation, or destination therapy.

CASE REPORT

A 61-year-old man with past medical history significant for advanced congestive heart failure from ischemic cardiomyopathy, status post LVAD (HeartMate II; Thoratec Corporation, Pleasanton, CA) placement 2009 as destination therapy, presented to the Emergency Department (ED) with implantable cardiac defibrillators firing four times that morning. While in the care of Emergency Medical Services, he was in ventricular tachycardia, and they gave him a bolus of amiodarone 150 mg intravenously prior to arrival in the ED. He was reportedly alert and oriented without any chest pain on arrival to the ED, where an electrocardiogram was obtained showing polymorphic ventricular tachycardia. WHY SHOULD AN EMERGENCY PHYSICIAN BE AWARE OF THIS?: Emergency physicians must be familiar with the atypical presentations of potentially lethal dysrhythmias in this patient population. They must also be familiar with the major adverse events after LVAD implantation. These include device malfunction, cardiac dysrhythmias, bleeding, thromboembolism, neurological events, and infection. The causes of device malfunction can include thrombus formation with hemolysis, mechanical failure of the impeller, and driveline lead fractures with electric failure. Although time is critical in the heart failure patient with an LVAD failure or complication, expert consultation with cardiology or the LVAD specialist should occur when possible.