Predictors and clinical relevance of ventricular tachyarrhythmias in ambulatory patients with a continuous flow left ventricular assist device

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.

Management of incessant ventricular arrhythmias in a patient with left ventricular assist device: a case report

BACKGROUND

The implantation of left ventricular assist devices (LVADs) as a bridge to transplantation or as destination therapy in end-stage heart failure patients is frequently complicated by the emergence of ventricular arrhythmias (VAs). These arrhythmias have been implicated in precipitating deleterious clinical outcomes, increased mortality rates and augmented healthcare expenditures.

CASE PRESENTATION

We present a challenging case of a 49-year-old male with a history of dilated cardiomyopathy who received an LVAD. Post-implantation, the patient suffered from intractable VAs, leading to multiple rehospitalizations and hemodynamic deterioration. Despite exhaustive medical management and electrical cardioversion attempts, the patient's VAs persisted, ultimately necessitating prioritization for cardiac transplantation.

DISCUSSION

This case highlights the challenges in managing VAs in LVAD patients and the importance of multidisciplinary collaboration. While pharmacological intervention is the initial strategy, catheter ablation may be considered in selected cases when medication is insufficient. In instances of intractable VAs, expeditious listing for heart transplantation as a high-priority candidate is advisable when feasible.

Ventricular Arrhythmias and Sudden Cardiac Death in Left Ventricular Assist Device Patients Without Implantable Cardioverter Defibrillators

Patients with left ventricular assist devices (LVAD) can develop sustained ventricular arrhythmias (VA). The history and presentation of VA in implantable cardioverter defibrillator (ICD)-naive patients with LVAD is not well described in the literature and the risks/benefits of ICD implantation are unknown. This single-center retrospective cohort study included patients >18 years old who did not have an ICD during LVAD implantation from 2010 to 2022. The primary outcome was VA event rate per 100 patient-years. Two hundred thirty-seven patients underwent LVAD implantation and we identified 46 (19.4%) ICD naive patients. The etiology of heart failure in most patients was nonischemic cardiomyopathy (67.4%). Of all patients, only five were found to have documented VA. Only two episodes of VA occurred in the ambulatory setting. The estimated index VA rate was 5.89 events per 100 patient-years in our entire ICD-naive LVAD population. In the ambulatory ICD-naive population, the estimated VA rate was 2.42 events per 100 patient-years with no associated mortality. The rate of index VA in ICD-naive patients was below thresholds associated with benefits from ICD insertion. No ambulatory mortality from VA was seen and VA was well tolerated by the LVAD population. Perioperative VA in this population is associated with high mortality.

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.

Design and characteristics of the prophylactic intra-operative ventricular arrhythmia ablation in high-risk LVAD candidates (PIVATAL) trial

BACKGROUND

The use of a Left Ventricular Assist Device (LVAD) in patients with advanced heart failure refractory to optimal medical management has progressed steadily over the past two decades. Data have demonstrated reduced LVAD efficacy, worse clinical outcome, and higher mortality for patients who experience significant ventricular tachyarrhythmia (VTA). We hypothesize that a novel prophylactic intra-operative VTA ablation protocol at the time of LVAD implantation may reduce the recurrent VTA and adverse events postimplant.

METHODS

We designed a prospective, multicenter, open-label, randomized-controlled clinical trial enrolling 100 patients who are LVAD candidates with a history of VTA in the previous 5 years. Enrolled patients will be randomized in a 1:1 fashion to intra-operative VTA ablation (n = 50) versus conventional medical management (n = 50) with LVAD implant. Arrhythmia outcomes data will be captured by an implantable cardioverter defibrillator (ICD) to monitor VTA events, with a uniform ICD programming protocol. Patients will be followed prospectively over a mean of 18 months (with a minimum of 9 months) after LVAD implantation to evaluate recurrent VTA, adverse events, and procedural outcomes. Secondary endpoints include right heart function/hemodynamics, healthcare utilization, and quality of life.

CONCLUSION

The primary aim of this first-ever randomized trial is to assess the efficacy of intra-operative ablation during LVAD surgery in reducing VTA recurrence and improving clinical outcomes for patients with a history of VTA.

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.

Safety and Efficacy of Prophylactic Amiodarone After Left Ventricular Assist Device

The prophylactic use of amiodarone to reduce the incidence of postoperative arrhythmias is effective for patients undergoing general cardiac surgeries; however, no data exists for the use of prophylactic amiodarone to prevent postoperative arrhythmias after CF-LVAD. This single-center, retrospective analysis compared patients with CF-LVADs placed between April 2014 and June 2020 who received prophylactic postoperative amiodarone to those who did not. Based on institution practice at the respective times, patients with a CF-LVAD placed between April 2014 and June 2018 were included in the group receiving postoperative amiodarone arrhythmia prophylaxis and patients with a CF-LVAD placed July 2018 to June 2020 were included in the group not receiving arrhythmia prophylaxis. The primary outcome was the incidence of first occurring atrial or ventricular arrhythmia from CF-LVAD placement to 21 days or hospital discharge. Sixty patients received amiodarone for arrhythmia prophylaxis and 27 patients did not receive prophylaxis. The primary outcome occurred in 40% of the prophylaxis group and 66.7% in the no prophylaxis group (RR, 0.60; 95% CI, 0.40-0.90; p = 0.038). In patients receiving CF-LVADs, the use of prophylactic amiodarone was associated with a reduction in the incidence of postoperative arrhythmias, which was driven primarily by a reduction in postoperative atrial arrhythmias, without significantly increasing the rate of amiodarone-related adverse events.

Impact of Ventricular Arrhythmia on LVAD Implantation Admission Outcomes

INTRODUCTION

Ventricular arrhythmias (VAs) are common after left ventricular assist device (LVAD) implantation though data are mixed on whether these events have an impact on mortality.

METHODS

The National Inpatient Sample (NIS) database from 2002 - 2019 was queried for LVAD implantation admissions. Secondary ICD codes were analyzed to assess for the occurrence of VAs during this admission. Propensity score matching (PSM) was used to control for confounding variables between those with versus without VAs.

RESULTS

The NIS database from 2002 - 2019 contained 43,936 admissions with LVAD implantation. VAs occurred in 19,985 (45.4%) patients. After PSM, the study cohort consisted of 39,989 patients, 19,985 (50.0%) of which had a secondary diagnosis of VA during the admission. When compared to those without VA, those with VA were at no higher risk for in-hospital mortality (adjusted odds ratio 1.011, 99.9% CI 0.956 - 1.069, p = 0.699). Those with a VA were at higher risk for cardiogenic shock and requiring mechanical ventilation, tracheostomy, and percutaneous endoscopic gastrostomy placement. Patients with a VA were also at lower risk for device thrombosis. Conversely, the VA group was at no higher risk for stroke. In comparing trends from 2002 to 2019, the incidence of VAs has increased, while the mortality rate of those with and without VAs has decreased during this same period.

CONCLUSION

In this retrospective study of the NIS database, VAs were common (45.4%) during the LVAD implantation admission. However, the occurrence of VAs during the implantation admission did not alter in-hospital mortality. More longitudinal studies are required to assess the long-term impact of VAs on mortality. In comparing trends from 2002 - 2019, the incidence of VAs has increased, while the mortality rate of those with and without VAs has decreased.

Impact of sleep-disordered breathing on ventricular tachyarrhythmias after left ventricular assist device implantation

Sleep-disordered breathing (SDB) is associated with an increased risk of adverse events in patients with heart failure (HF); however, its impact in patients implanted with a left ventricular assist device (LVAD) remains unclear. We aimed to investigate the prevalence of SDB in patients with LVAD and its impact on their clinical outcomes. Fifty consecutive patients with LVAD who underwent portable sleep monitoring between September 2017 and April 2018 were prospectively enrolled, and they were followed up for 170 ± 36 days. According to their respiratory disturbance indexes (RDIs), they were categorized into the SDB group (RDI ≥ 15, n = 12) and the non-SDB group (RDI < 15, n = 38). The incidence of adverse events during the follow-up period was investigated after enrollment. Multivariate logistic regression analysis revealed significant differences in SDB in LVAD-implanted patients in terms of the logarithmic transformation brain natriuretic peptide (BNP) values (p = 0.005). The optimal BNP cut-off value for SDB prediction in LVAD-implanted patients was 300 pg/mL (sensitivity: 58.3%, specificity: 94.7%). During follow-up, ventricular tachyarrhythmias (VTas) occurred significantly more frequently in the SDB group (4 [33%] vs. 2 [5%] patients, p = 0.02); Atrial tachyarrhythmia (ATa) also tended to occur more frequently in the SDB group (2 [25%] vs. 2 [2%] patients, p = 0.07). SBD was prevalent in 24% of the LVAD-implanted patients with advanced HF. Furthermore, SDB was significantly associated with high BNP levels and was also potentially associated with subsequent incidence of VTa in patients with LVAD.

Carbon Monoxide Diffusing Capacity Predicts Cardiac Readmission in Patients Undergoing Left Ventricular Assist Device Implantation in Japan

Carbon monoxide diffusion capacity (DLCO) is impaired in heart failure patients; however, its clinical impact has not been well investigated in the left ventricular assist device (LVAD) population. We explored the predictive value of preoperative DLCO in the survival and cardiac readmission rates after LVAD implantation. Seventy-six patients who received continuous-flow LVAD as bridge-to-transplant therapy from November 2007 to September 2018 and underwent pulmonary function test before LVAD implantation were included. The primary study endpoints were death and readmission for heart failure or arrhythmia (cardiac readmission). Patients were stratified into two groups according to the percent of predicted DLCO (%DLCO). Pulmonary vascular resistance (PVR) was equivocal between the groups preoperatively, whereas the low DLCO group (%DLCO < 80%) showed significantly high PVR postoperatively. The mortality rate was not different between the groups. The 2 year cardiac readmission rate was 33.5% in the low DLCO group and 8.7% in the high DLCO group (%DLCO ≥ 80%) (P = 0.028). The %DLCO was associated with cardiac readmission in univariate and multivariate analyses (hazard ratio: 4.32; 95% CI: 1.50-15.9; P = 0.005). Low %DLCO was associated with high PVR postoperatively and was a risk factor for cardiac readmission after LVAD implantation.

Association between early ventricular arrhythmias and mortality in destination vs. bridge patients on continuous flow LVAD support

The association between ventricular arrhythmias (VAs) and mortality in patients supported by continuous flow left ventricular assist devices (LVAD) remains controversial. To evaluate the association between pre-implantation, early (≤ 30 day) post-implantation VAs and mortality in bridge to transplant (BTT) and destination therapy (DT) LVAD patients, separately. The risk factors for post LVAD VAs were also investigated. In this observational cohort study, we included 341 patients who received a first time, continuous flow LVAD between January 1st 2010 and July 30th 2018. We used Kaplan–Meier curves and multivariable cox regression analyses to study the association between VAs and mortality in the BTT and DT populations. The mean age of the cohort was 58 ± 14 years, with 82% males, 53% had ischemic cardiomyopathy, and 45% were DT. The mean follow-up was 2.2 ± 2.1 years. In both BTT and DT cohorts, pre LVAD VAs were not associated with mortality after LVAD implantation (log-rank p = 0.95 and p = 0.089, respectively). In the BTT population, early post-LVAD VAs were not statistically associated with increased mortality (log rank p = 0.072). In the DT patients, early post LVAD VAs were associated with a 67% increase in the hazards rate of mortality on LVAD support (HR 1.67 [1.05–2.65], p = 0.029). The final model was adjusted for type of cardiomyopathy, INTERMACS profile, glomerular filtration rate, post LVAD atrial fibrillation, age and cerebrovascular events. Early post-LVAD VA is common after LVAD implantation and is an independent predictor of mortality in the DT LVAD population.

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.

Successful Open Chest Epicardial Ablation for Refractory Ventricular Tachycardia in an LVAD Recipient

A patient with history of dilated cardiomyopathy, a cardiac resynchronization therapy defibrillator, and endocardial ablation presented for refractory ventricular tachycardia 3 years after implantation of a Jarvik 2000 left ventricular assist device (Jarvik Heart, Inc., New York, New York). Open-chest epicardial ablation safely and effectively terminated the arrhythmia, without ventricular tachycardia recurrence at 9-month follow-up and in the absence of complications during the hospital stay. (Level of Difficulty: Advanced.)

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.

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

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

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

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

Management of ventricular arrhythmias in patients with LVAD

PURPOSE OF REVIEW

Left ventricular assist devices (LVADs) have extended the life expectancy of patients with heart failure. The hemodynamic support afforded by LVADs in this population has also resulted in patients having prolonged ventricular arrhythmias. The purpose of this article is to review the mechanisms of ventricular arrhythmias in LVADs and the available management strategies.

RECENT FINDINGS

Recent evidence suggests that prolonged ventricular arrhythmias may result in increased mortality in patients with LVADs.

SUMMARY

Successful management of ventricular arrhythmias in patients with LVAD requires interdisciplinary collaboration between electrophysiology and heart failure specialists. Medical management, including changes to LVAD changes, heart failure medication management, and antiarrhythmics constitute the initial treatment for ventricular arrhythmias. Surgical or endocardial ablation are reasonable options if VAs are refractory.

Delineating Pathways to Death by Multisystem Organ Failure in Patients With a Left Ventricular Assist Device

BACKGROUND

This study delineates the sequences of adverse events (AEs) preceding mortality attributed to multisystem organ failure (MSOF) in patients with a left ventricular assist device (LVAD).

METHODS

We analyzed 3765 AEs after 536 LVAD implants recorded in The Society of Thoracic Surgeons Intermacs data registry between 2006 and 2015 that resulted in MSOF death. Hierarchical clustering identified and visualized quantitatively unique clusters of patients with similar AE profiles. Markov modeling was used to illustrate the AE sequences that led to MSOF death within the clusters. Cox proportional hazard models determined the risk-adjusted, preimplant predictors of MSOF.

RESULTS

We identified 2 distinct MSOF clusters based on their proportion of AE types and survival time. The early-death cluster (418 patients, 2304 AEs) had a median survival of 1 month (interquartile range, 3-6 months), whereas the late-death cluster (118 patients, 1,461 AEs) had a median survival of 11 months (interquartile range, 6-22 months). The predominant AE sequences in the early-death and late-death clusters were renal failure, to respiratory failure, to death (62%) and bleeding, to infection, to respiratory failure, to death (45%), respectively. Significant risk-adjusted preimplant predictors of MSOF included line sepsis (hazard ratio [HR] 3.0; 95% confidence interval [CI], 1.1-8.2), extracorporeal membrane oxygenation (HR, 2.2; 95% CI, 1.2-3.9), and dialysis or ultrafiltration (HR, 2.1; 95% CI, 1.5-3.0).

CONCLUSIONS

This analysis identified 2 AE clusters and the predominant sequences that result in MSOF-associated mortality. MSOF develops in 1 cluster of patients after chronic bleeding and repeated infections but has prolonged survival, while another group dies early after renal and respiratory complications.

Safety of Outpatient Milrinone Infusion in End-Stage Heart Failure: ICD-Level Data on Atrial Fibrillation and Ventricular Tachyarrhythmias

BACKGROUND

Milrinone infusion is one of a few select "non-device" therapies for patients with New York Heart Association (NYHA) class IV, stage D heart failure, which has been associated with an increase in ventricular tachyarrhythmia and atrial fibrillation. Milrinone improves hemodynamics and provides symptomatic relief. Many patients with end-stage heart failure die from cardiac pump failure, and the impact of ventricular tachyarrhythmia and atrial fibrillation on their mortality is unclear.

METHODS

This is a retrospective study of 98 consecutive patients receiving outpatient milrinone in a single center from 2008 to 2016. The primary endpoint of the study was overall survival on milrinone. Secondary endpoints were incidence of post-milrinone implantable cardioverter defibrillator (ICD) shocks and development of ventricular tachyarrhythmia or atrial fibrillation.

RESULTS

Median survival was 581 ± 96 days with no difference between those with prior ventricular tachyarrhythmia and those without at 1 month (92% vs 97%, P = 0.34), 6 months (67% vs 73%, P = 0.75), and 12 months (67% vs 61%, P = 0.88). Seven out of 12 (58%) patients with prior ventricular tachyarrhythmia had ICD shocks, as compared to 5 out of 78 (6.4%) (P <0.001). Thirty-five patients had atrial fibrillation prior to starting milrinone, which decreased to 72% (P <0.05) by the third follow-up time period (7-9 months). Amiodarone use was protective against new onset atrial fibrillation.

CONCLUSIONS

Patients with stage D heart failure with a history of ventricular tachyarrhythmia have similar survival on outpatient milrinone compared to those without. However, those with prior ventricular tachyarrhythmia received more ICD shocks for more ventricular tachyarrhythmias. Milrinone remains a viable therapy for patients with stage D heart failure with limited therapeutic options.

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.

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.

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.

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

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

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.

Myocardial Irritation from a Left Ventricular Assist Device Resulting in Refractory Ventricular Tachycardia

BACKGROUND

Due to an increasing prevalence of heart failure but a steady rate of heart transplantation, the number of left ventricular assist devices (LVADs) implanted is growing. These patients present to emergency departments (EDs) with a variety of complications from their implanted device as well as their baseline cardiomyopathy. One-third of patients will present with a dysrhythmia, the most common of which is ventricular tachycardia.

CASE REPORT

A 77-year-old man with nonischemic cardiomyopathy and HeartMate II LVAD presented with sustained ventricular tachycardia and 43 automatic implantable cardioverter-defibrillator (AICD) discharges. Due to left ventricular remodeling, ongoing diuresis, and positioning of his LVAD inflow cannula against his interventricular septum, a likely dysrhythmogenic foci, he quickly decompensated with sedation while in the ED. WHY SHOULD AN EMERGENCY PHYSICIAN BE AWARE OF THIS?: Refractory ventricular tachycardia is a common dysrhythmia for LVAD patients and may lead to full cardiopulmonary arrest. Common strategies such as chest compressions are used only in limited scenarios, but medical management is possible. This should focus on resolution of the dysrhythmia and identification of the etiology, including possible mechanical compromise.

Catheter Ablation of Ventricular Tachycardia in Patients With a Ventricular Assist Device: A Systematic Review of Procedural Characteristics and Outcomes

OBJECTIVES

This is a systematic review summarizing the procedural characteristics and outcomes of ventricular assist device (VAD)-related ventricular tachycardia (VT) ablation.

BACKGROUND

Drug-refractory VT refractory commonly develops post-VAD implantation. Procedural and outcome data come from small series or case reports.

METHODS

An electronic search was performed using major databases. Primary outcomes were VT recurrence, mortality, and cardiac transplantation. Secondary endpoints were acute procedural success and procedural complications.

RESULTS

Eighteen studies were included, with a total of 110 patients (mean age 59.6 ± 11 years, 89% men; VT storm 34%). Scar-related re-entry was the predominant mechanism of VT (90.3%) and cannula-related VT in 19.3% cases. Electroanatomical mapping interference occurred in 1.8% of cases; there were no reports of catheter entrapment. Noninducibility of clinical VT was achieved in 77.9%; procedural complications occurred in 9.4%. At a mean follow-up of 263.5 ± 267.0 days, VT recurred in 43.6%, 23.4% underwent cardiac transplant, and 48.1% died. There were no procedural-related deaths and no death was directly related to ventricular arrhythmia. In follow-up, there was a significant reduction in implantable cardioverter-defibrillator therapies or shocks (57.1% vs. 23.8%). Ablation allowed VT storm termination in 90% of patients.

CONCLUSIONS

VAD-related VT is predominantly related to pre-existing intrinsic myocardial scar rather than inflow cannula site insertion. Catheter ablation is a reasonable treatment strategy, albeit with expectedly high rate of recurrence, transplantation, and mortality related to severe underlying disease.

Impact of Recurrent Ventricular Tachyarrhythmia on Outcome in Japanese Heart Transplant Candidates With a Left Ventricular Assist Device

BACKGROUND

Recurrent ventricular tachyarrhythmias (VTA) are "A factor" modifiers in the Interagency Registry for Mechanically Assisted Circulatory Support profile. The effect of recurrent VTA on clinical outcome, however, is controversial. We evaluated the impact of recurrent VTA on outcome in Japanese heart transplant candidates with a left ventricular assist device (LVAD). Methods and Results: Sixty-six adult patients with advanced heart failure who were listed for heart transplantation between January 2005 and October 2017 were enrolled in the study. Recurrent VTA (modifier A status) was defined as a sustained ventricular tachycardia or fibrillation that required implantable cardioverter defibrillator shocks or an external defibrillator more than twice weekly. The primary outcome was death from any cause. The secondary outcomes were the first occurrence of VTA and recurrent VTA after LVAD implantation. Sixteen patients (24%) met the criteria for modifier A status, and 15 patients had an LVAD implanted. During a median follow-up of 1,124 days, 21 of 60 patients with an LVAD died. There was a significantly higher mortality rate in LVAD patients with modifier A status than in those who did not meet the modifier A criteria. On multivariate analysis, patients with modifier A status had an increased risk of mortality (HR, 3.43; 95% CI: 1.30-8.61, P=0.001).

CONCLUSIONS

Recurrent VTA might be a marker for worse outcome in Japanese heart transplant candidates with an LVAD.

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).

Characterization of Ventricular Tachycardia After Left Ventricular Assist Device Implantation as Destination Therapy: A Single-Center Ablation Experience

OBJECTIVES

This study sought to report mechanisms of ventricular tachycardia (VT) and outcomes of VT ablation in patients with a left ventricular assist device (LVAD) as destination therapy.

BACKGROUND

Continuous flow LVAD implantation plays a growing role in the management of end-stage heart failure, and VT is common. There are limited reports of VT ablation in patients with a destination LVAD.

METHODS

Patients with a continuous-flow LVAD referred for VT ablation from 2010 to 2016 were analyzed retrospectively. Baseline patient characteristics, procedural data, and clinical follow-up were evaluated. Arrhythmia-free survival was assessed.

RESULTS

Twenty-one patients (90% male, 62 ± 10 years) underwent catheter ablation of VT at a median of 191 days (interquartile range: 55 to 403 days) after LVAD implantation (15 HeartMate II, 6 HeartWare HVAD). Five patients (24%) had termination (n = 4) or slowing (n = 1) of VT with ablation near the apical inflow cannula, and 3 (14%) had bundle-branch re-entry. Freedom from recurrent VT among surviving patients was 64% at 1 year, with overall survival 67% at 1 year for patients without arrhythmia recurrence and 29% for patients with recurrence (p = 0.049). One patient had suspected pump thrombosis within 30 days of the ablation procedure, with no other major acute complications.

CONCLUSIONS

In this relatively large, single-center experience of VT ablation in destination LVAD, freedom from recurrent VT and implantable cardioverter-defibrillator shocks was associated with improved 1-year survival. Bundle branch re-entry was more prevalent than anticipated, and cannula-adjacent VT was less common. This challenging population remains at risk for late pump thrombosis and mortality.

Atrial Arrhythmias and Electroanatomical Remodeling in Patients With Left Ventricular Assist Devices

BACKGROUND

The incidence, predictors, and impact of atrial arrhythmias along with left atrial structural changes in patients with left ventricular assist devices (LVADs) remain undetermined.

METHODS AND RESULTS

All patients who underwent LVAD implantation from 2008 to 2015 at the University of Chicago Medical Center were included. Electronic medical records, electrocardiograms, echocardiograms, and cardiac electrical device interrogations were reviewed. The association of arrhythmias and clinical covariates with survival was evaluated by Kaplan-Meier and Cox proportional hazards analyses. A total of 331 patients were followed for a median of 330 days (range 0-2306 days). Mean age was 57.8±12.8 years, 256 participants (77.3%) were male, mean left ventricular ejection fraction was 20±6.6%, and 124 (37.5%) had ischemic cardiomyopathy. Atrial arrhythmias (53.8%) were highly prevalent and frequently coexisted before LVAD implantation: atrial fibrillation (AF) in 45.9%, atrial flutter in 13.9%, atrial tachycardia in 6.9%, and atrioventricular nodal reentrant tachycardia in 1.2%. New-onset AF was documented in 14 patients (7.8% of patients without prior AF) after the first 30 days with an LVAD. Increasing age, renal insufficiency, and lung disease were predictors of new-onset AF after LVAD implantation. Of patients with paroxysmal AF, 43% had no further AF after LVAD. Left atrial size and volume index improved with LVAD (P<0.005). History of persistent AF, atrial tachycardia, ventricular arrhythmia, coronary artery bypass, and low albumin were associated with decreased survival.

CONCLUSIONS

Atrial arrhythmias are significantly prevalent in patients who require LVAD and are associated with increased mortality; however, LVADs induce favorable atrial structural and electrical remodeling.