Implantable Cardioverter Defibrillators in Patients With Continuous Flow Left Ventricular Assist Devices: Utilization Patterns, Related Procedures, and Complications

Appropriate and inappropriate ICD shocks in patients with LVADs: Prevalence, associated factors, and etiologies

BACKGROUND

Implantable cardioverter-defibrillator (ICD) shocks are a common complication after left ventricular assist device (LVAD) implantation; however, data on their frequency and causes are limited.

OBJECTIVE

The purpose of this study was to define the incidence, programming, patient characteristics, and factors associated with appropriate and inappropriate ICD shocks in persons with LVADs.

METHODS

We performed a retrospective review at Duke University Hospital of all LVAD recipients implanted between January 1, 2013, to June 30, 2019, with a preexisting ICD. ICD shocks were adjudicated by the treating physician and a second reviewer for the purpose of this study.

RESULTS

Among 421 patients with an ICD in situ undergoing LVAD implant, 147 (33.9%) had at least 1 shock after LVAD implantation. Among 134 patients with complete device history, a total of 330 shock episodes occurred: 255 (77.3%) appropriate and 75 (22.7%) inappropriate. Etiologies for inappropriate shocks included supraventricular tachycardia (n = 66 [20.0%]), physiological oversensing (n = 1 [0.3%]), and nonphysiological oversensing (n = 8 [2.4%]) including LVAD electromagnetic interference (n = 1 [0.3%]). ICD programming with shorter detection delay (P <.001) and absence of antitachycardia pacing programming (P = .001) in high-rate zones was seen more commonly in inappropriate shock than appropriate shock.

CONCLUSIONS

The rate of inappropriate shocks in LVAD recipients is very high and most often is due to supraventricular arrhythmias. LVAD electromagnetic interference is a rare cause of ICD shock. Implementation of current consensus American Heart Association recommendations for LVAD programming with long detection delays and high rate cutoffs may help prevent inappropriate ICD shocks.

18F-FDG PET/CT and radiolabeled leukocyte SPECT/CT imaging for the evaluation of cardiovascular infection in the multimodality context: ASNC Imaging Indications (ASNC I2) Series Expert Consensus Recommendations from ASNC, AATS, ACC, AHA, ASE, EANM, HRS, IDSA, SCCT, SNMMI, and STS

This document on cardiovascular infection, including infective endocarditis, is the first in the American Society of Nuclear Cardiology Imaging Indications (ASNC I2) series to assess the role of radionuclide imaging in the multimodality context for the evaluation of complex systemic diseases with multi-societal involvement including pertinent disciplines. A rigorous modified Delphi approach was used to determine consensus clinical indications, diagnostic criteria, and an algorithmic approach to diagnosis of cardiovascular infection including infective endocarditis. Cardiovascular infection incidence is increasing and is associated with high morbidity and mortality. Current strategies based on clinical criteria and an initial echocardiographic imaging approach are effective but often insufficient in complicated cardiovascular infection. Radionuclide imaging with 18F-fluorodeoxyglucose (FDG) positron emission tomography/computed tomography (CT) and single photon emission computed tomography/CT leukocyte scintigraphy can enhance the evaluation of suspected cardiovascular infection by increasing diagnostic accuracy, identifying extracardiac involvement, and assessing cardiac implanted device pockets, leads, and all portions of ventricular assist devices. This advanced imaging can aid in key medical and surgical considerations. Consensus diagnostic features include focal/multi-focal or diffuse heterogenous intense 18F-FDG uptake on valvular and prosthetic material, perivalvular areas, device pockets and leads, and ventricular assist device hardware persisting on non-attenuation corrected images. There are numerous clinical indications with a larger role in prosthetic valves, and cardiac devices particularly with possible infective endocarditis or in the setting of prior equivocal or non-diagnostic imaging. Illustrative cases incorporating these consensus recommendations provide additional clarification. Future research is necessary to refine application of these advanced imaging tools for surgical planning, to identify treatment response, and more.

18F-FDG PET/CT and radiolabeled leukocyte SPECT/CT imaging for the evaluation of cardiovascular infection in the multimodality context: ASNC Imaging Indications (ASNC I2) Series Expert Consensus Recommendations from ASNC, AATS, ACC, AHA, ASE, EANM, HRS, IDSA, SCCT, SNMMI, and STS

This document on cardiovascular infection, including infective endocarditis, is the first in the American Society of Nuclear Cardiology Imaging Indications (ASNC I2) series to assess the role of radionuclide imaging in the multimodality context for the evaluation of complex systemic diseases with multi-societal involvement including pertinent disciplines. A rigorous modified Delphi approach was used to determine consensus clinical indications, diagnostic criteria, and an algorithmic approach to diagnosis of cardiovascular infection including infective endocarditis. Cardiovascular infection incidence is increasing and is associated with high morbidity and mortality. Current strategies based on clinical criteria and an initial echocardiographic imaging approach are effective but often insufficient in complicated cardiovascular infection. Radionuclide imaging with 18F-fluorodeoxyglucose (FDG) positron emission tomography/computed tomography (CT) and single photon emission computed tomography/CT leukocyte scintigraphy can enhance the evaluation of suspected cardiovascular infection by increasing diagnostic accuracy, identifying extracardiac involvement, and assessing cardiac implanted device pockets, leads, and all portions of ventricular assist devices. This advanced imaging can aid in key medical and surgical considerations. Consensus diagnostic features include focal/multi-focal or diffuse heterogenous intense 18F-FDG uptake on valvular and prosthetic material, perivalvular areas, device pockets and leads, and ventricular assist device hardware persisting on non-attenuation corrected images. There are numerous clinical indications with a larger role in prosthetic valves, and cardiac devices particularly with possible infective endocarditis or in the setting of prior equivocal or non-diagnostic imaging. Illustrative cases incorporating these consensus recommendations provide additional clarification. Future research is necessary to refine application of these advanced imaging tools for surgical planning, to identify treatment response, and more.

18F-FDG PET/CT and radiolabeled leukocyte SPECT/CT imaging for the evaluation of cardiovascular infection in the multimodality context: ASNC Imaging Indications (ASNC I2) Series Expert Consensus Recommendations from ASNC, AATS, ACC, AHA, ASE, EANM, HRS, IDSA, SCCT, SNMMI, and STS

This document on cardiovascular infection, including infective endocarditis, is the first in the American Society of Nuclear Cardiology Imaging Indications (ASNC I2) series to assess the role of radionuclide imaging in the multimodality context for the evaluation of complex systemic diseases with multi-societal involvement including pertinent disciplines. A rigorous modified Delphi approach was used to determine consensus clinical indications, diagnostic criteria, and an algorithmic approach to diagnosis of cardiovascular infection including infective endocarditis. Cardiovascular infection incidence is increasing and is associated with high morbidity and mortality. Current strategies based on clinical criteria and an initial echocardiographic imaging approach are effective but often insufficient in complicated cardiovascular infection. Radionuclide imaging with 18F-fluorodeoxyglucose (FDG) positron emission tomography/computed tomography (PET/CT) and single photon emission computed tomography/CT leukocyte scintigraphy can enhance the evaluation of suspected cardiovascular infection by increasing diagnostic accuracy, identifying extracardiac involvement, and assessing cardiac implanted device pockets, leads, and all portions of ventricular assist devices. This advanced imaging can aid in key medical and surgical considerations. Consensus diagnostic features include focal/multi-focal or diffuse heterogenous intense 18F-FDG uptake on valvular and prosthetic material, perivalvular areas, device pockets and leads, and ventricular assist device hardware persisting on non-attenuation corrected images. There are numerous clinical indications with a larger role in prosthetic valves, and cardiac devices particularly with possible infective endocarditis or in the setting of prior equivocal or non-diagnostic imaging. Illustrative cases incorporating these consensus recommendations provide additional clarification. Future research is necessary to refine application of these advanced imaging tools for surgical planning, to identify treatment response, and more.

[Cardiac rehabilitation in LVAD patients : Aspects regarding exercise and rhythm]

After implantation of a left ventricular assist device (LVAD), it is strongly recommended that patients participate in an inpatient cardiac rehabilitation program (CR). Relevant topics during CR include sports and exercise therapy as well as aspects of cardiac rhythm control. Over time, LVAD patients usually regain a good quality of life and an adequate functional capacity can be observed. However, maximum performance values remain markedly reduced, in part due to the fixed LVAD pump speed and the limited total cardiac output. Therefore, structured long-term exercise training programs (even beyond CR phase II) are of particular importance in order to optimize neuromuscular control and muscle metabolism. Limitations to physical performance values may also be caused by the occurrence of supraventricular and/or ventricular arrhythmias. In both cases, the cause is an increasing hemodynamic impairment of the right heart, which may also lead to a reduced LVAD pump flow. In addition, inadequate setting of other cardiac implantable electronic devices (e.g., implantable cardioverter-defibrillator [ICD] or cardiac resynchronization therapy with defibrillator [CRT-D]) may also have a crucial impact on hemodynamics after LVAD implantation. In this article, we will discuss specific aspects of LVAD therapy related to exercise and rhythm control, particularly in the context of CR programs.

HFSA Expert Consensus Statement on the Medical Management of Patients on Durable Mechanical Circulatory Support

The medical management of patients supported with durable continuous flow left ventricular assist device (LVAD) support encompasses pharmacologic therapies administered in the preoperative, intraoperative, postoperative and chronic LVAD support stages. As patients live longer on LVAD support, the risks of LVAD-related complications and progression of cardiovascular and other diseases increase. Using existing data from cohort studies, registries, randomized trials and expert opinion, this Heart Failure Society of America Consensus Document on the Medical Management of Patients on Durable Mechanical Circulatory Support offers best practices on the management of patients on durable MCS, focusing on pharmacological therapies administered to patients on continuous flow LVADs. While quality data in the LVAD population are few, the utilization of guideline directed heart failure medical therapies (GDMT) and the importance of blood pressure management, right ventricular preload and afterload optimization, and antiplatelet and anticoagulation regimens are discussed. Recommended pharmacologic regimens used to mitigate or treat common complications encountered during LVAD support, including arrhythmias, vasoplegia, mucocutaneous bleeding, and infectious complications are addressed. Finally, this document touches on important potential pharmacological interactions from anti-depressants, herbal and nutritional supplements of relevance to providers of patients on LVAD support.

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.

Electromagnetic interference from left ventricular assist devices detected in patients with implantable cardioverter-defibrillators

INTRODUCTION

Electromagnetic interference (EMI) from left ventricular assist devices (LVADs) can cause implantable cardioverter-defibrillator (ICD) oversensing. We sought to assess the frequency of inappropriate shocks/oversensing due to LVAD-related EMI and prospectively compare integrated (IB) versus dedicated bipolar (DB) sensing in patients with LVADs.

METHODS

Single-center study in LVAD patients with Medtronic or Abbott ICDs between September 2017 and March 2020. We excluded patients that were pacemaker dependent. Measurements were obtained of IB and DB sensing and noise to calculate a signal-to-noise ratio (SNR). Device checks were reviewed to assess appropriate and inappropriate sensing events.

RESULTS

Forty patients (age 52 ± 14 years, 75% men, 38% ischemic cardiomyopathy) were included with the median time between LVAD implantation and enrollment of 6.7 months (2.3, 11.4 months). LVAD subtypes included: HeartWare (n = 22, 55%), Heartmate II (n = 10, 25%), and Heartmate III (n = 8, 20%). Over a follow-up duration of 21.6 ± 12.9 months after LVAD implantation, 5% of patients (n = 2) had oversensing of EMI from the LVAD (both with HeartWare LVADs and Abbott ICDs) at 4 days and 10.8 months after LVAD implantation. Both patients underwent adjustment of ventricular sensing with resolution of oversensing and no further events over 5 and 15 months of further follow-up. The SNR was similar between IB and DB sensing (50 [29-67] and 57 [41-69], p = 0.89).

CONCLUSION

ICD oversensing of EMI from LVADs is infrequent and can be managed with reprogramming the sensitivity. There was no significant difference in the R-wave SNR with IB versus DB ICD leads.

Fusion cardiac resynchronization therapy in an left ventricular assist device patient from two devices and crossing leads: a case report

Background

Cardiac implanted electronic devices (CIED) have significantly improved the survival and quality of life in heart failure patients. Although implantable cardioverter-defibrillators (ICD) and cardiac resynchronization therapy (CRT) have a major role in patients with moderate to severe heart failure symptoms, the role of these devices in patients with a left ventricular assist device (LVAD) is not yet well defined. The burden of CIED-related procedures in patients with an LVAD is high. The price of lead malfunctions and pocket complications requires creative approaches to tackle CIED-related issues in this patient population.

Case summary

Here, we describe the clinical course of a 67-year-old ventricular pacing dependent LVAD patient with an ICD indication based on recurrent monomorphic ventricular tachycardias and a CRT indication due to previous deterioration of (right-sided) heart failure in the absence of biventricular pacing. We were confronted with impending right ventricular lead failure and bilateral venous access problems due to chronic subclavian vein occlusion in a patient with a total of five transvenous leads, therapeutic anticoagulation, and pronounced thoracic collaterals. We sought for a creative solution to be able to deliver effective biventricular fusion pacing with the existing leads from two contralateral pulse generators resulting in biventricular fusion pacing. This provided the solution to deliver effective CRT.

Discussion

This case illustrates the complexity of care and CIED-related decision-making in pacing dependent LVAD patients, in particularly those with an ICD and CRT indication.

Implantable cardioverter defibrillators in left ventricular assist device patients: Α systematic review and meta-analysis

Implantable cardioverter-defibrillators (ICDs) remain the standard of care in advanced heart failure with reduced ejection fraction patients for the prevention of sudden cardiac death. However, current guidelines remain conflicting with respect to the use of ICDs in patients supported with a continuous flow left ventricular assist device (CF-LVAD). The current review adhered to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. Studies comparing the use of ICD in patients with CF-LVADs were included. The 2 primary outcomes studied were all-cause mortality, and a successful bridge to heart transplantation. We calculated pooled odds ratios (ORs) with 95% confidence intervals (CIs). We also compared baseline characteristics between US and European studies, for CF-LVAD patients with an ICD. Among all studies, the use of an ICD was not associated with all-cause mortality in patients with CF-LVADs (OR: 0.85, 95% CIs: 0.64-1.12, p = 0.24). The presence of an ICD was associated with a trend towards increased likelihood of successful bridge to heart transplantation (OR: 1.12, 95% CI: 1.0-1.3, p = 0.06). A subgroup analysis of studies published by European centers revealed a significant decrease in pooled mortality (OR: 0.58, 95% CI: 0.4-0.83, p = 0.003) with the use of ICD, contrary to an increase in pooled mortality among studies published by US centers (OR: 1.2, 95% CI 1.02-1.33, p = 0.025). Moreover, we identified significant differences in baseline characteristics such as bridge to transplantation rate, Interagency Registry for Mechanically Assisted Circulatory Support profiles, and use of an intra-aortic balloon pump or extracorporeal membrane oxygenation preoperatively, between the US and European populations. While this meta-analysis did not show an overall survival benefit with the use of an ICD in CF-LVAD patients, it revealed significant differences in the derived benefit, in distinct patient populations. This might reflect differences in baseline patient characteristics and warrants further investigation.

Electromagnetic interference between implantable cardiac devices and continuous-flow left ventricular assist devices: a review

Many patients with continuous-flow left ventricular assist devices (CF-LVAD) have other, co-existing implantable cardiac devices. While such devices often function appropriately, there is potential for electromagnetic interference (EMI). A literature review was performed to identify cases of EMI between CF-LVAD and other implanted cardiac devices to better understand their etiology, outcomes, and the strategies used to overcome such interference. The cases identified included interference between CF-LVAD and pacemakers, implantable cardioverter-defibrillators, and cardiac resynchronization therapy. The EMI reported in the current literature can be broken down into two general categories: interference leading to difficulty establishing telemetry and interference leading to impaired electrical signal sensing. Such interference led to inappropriate shock delivery in some cases. The type of interference, and thus treatments, differed and were device dependent. The strategies employed to reduce interference included metal shielding, physical manipulation to increase the distance between devices, and even exchange of the implanted device with another brand of the same class. To avoid such EMI in the future, physicians must be aware of the reported interference between certain devices, and manufacturers must work more closely to increase the compatibility of implanted cardiac devices.

Wearable cardioverter defibrillator: bridging for implantable defibrillators in left ventricular assist device patients

There is currently conflicting data available regarding the use of implantable cardioverter-defibrillators (ICD) in left ventricular assist device (LVAD) patients. While the benefit of an ICD in heart failure patients is well demonstrated, such benefit has failed to reach the LVAD population. In lack of randomized control trial data on the topic of ICD use in LVAD recipients, major societal guidelines are in disagreement when comes to the topic of routine implantation of a permanent defibrillator in prospective ventricular assist device patients. Alternative permanent defibrillator strategies have been suggested for the LVAD population such as subcutaneous implantable cardioverter defibrillators (S-ICDs) but eligibility of patients for such practice remains disappointing. Although most of the heart failure patients undergoing LVAD implantation already bear an ICD, clinicians are left with the decision of de novo implanting an ICD in an important number of patients. Wearable cardioverter defibrillators could prove beneficial in LVAD recipients by utilizing them as a bridge to decision towards the implantation of a permanent defibrillator.

Implantable Cardioverter Defibrillators in Patients With Continuous Flow Left Ventricular Assist Devices: Utilization Patterns, Related Procedures, and Complications

Background

The effect of implantable cardioverter defibrillators (ICD) in patients with continuous flow left ventricular assist devices (LVADs) on outcomes has not been evaluated in a randomized clinical trial.

Methods and Results

This is a retrospective single‐center study that included patients who underwent continuous flow LVAD implantation at the Cleveland Clinic between October 2004 and March 2017. Patients were evaluated according to the presence or absence of ICD at the time of LVAD insertion. Among 486 patients in the study cohort, 387 (79.6%) had an ICD before LVAD insertion. Patients with ICD before LVAD were older and had lower use of pre‐LVAD inotropes, extracorporeal membrane oxygenation, and mechanical ventilation. There were 81 patients (21.4% of patients with ICD) who required 93 procedures after LVAD: 74 generator exchanges, 12 lead revisions, and 7 complete system removals because of infection. Of the 99 patients without ICD, 52 (53%) underwent ICD implantation: 29 for primary prevention and 23 for secondary prevention. Patients were followed for a median of 401 (interquartile range 150–966) days. The presence of a pre‐LVAD ICD was not associated with mortality in a multivariable model (hazard ratio 1.19, 95% CI 0.73–1.93, P=0.492), nor was the presence of an ICD at any point when analyzed as a time‐varying covariate (hazard ratio 1.05, 95% CI 0.50–2.20, P=0.907).

Conclusions

There is no apparent mortality benefit associated with an ICD in a contemporary cohort of patients with continuous flow LVADs to balance considerable morbidity involving ICD‐related procedures and complications.