Clinical Approach to Manage Gastrointestinal Bleeding with a Left Ventricular Assist Device (LVAD)

My Broken Heart

Audience

The target audience for the key learning objectives of this Left-Ventricular Assist Device (LVAD) simulation are emergency medicine residents. Other team members such as attendings, nurses, pharmacists, and technicians could potentially be integrated.

Introduction

Left ventricular assist devices (LVADs) are common bridge therapy for patients suffering from severe heart failure to cardiac transplant or destination therapy for non-transplant candidates.1 Emergency medicine physicians must be prepared for a variety of device complications that may result in an acute care presentation, such as drive-line infections, suction events, arrhythmias, and cardiac arrest with device failure. In a review investigating ED presentations for patients with LVADs, device-specific complaints were among the fewest, with the most common presentations involving bleeding, infection, and arrythmias.2 The present case involves a suction event that is precipitated by a gastrointestinal (GI) bleed, which has an incidence of 30% for LVAD patients.3 This case was developed for a technology failure-themed resident simulation competition during the Western Society for Academic Emergency Medicine (SEAM) conference held on April 1, 2022.

Educational Objectives

By the end of this simulation session, learners will be able to: 1) assess the hemodynamics of an LVAD patient by using a Doppler to determine mean arterial pressure, 2) Manage an arrhythmia in an LVAD patient with a suction event by addressing preload, 3) Identify and treat the source of hypovolemia (a massive lower gastrointestinal hemorrhage), 4) Perform clear closed-loop communication with other team members.

Educational Methods

This high-fidelity simulation case aims to train emergency medicine residents on recognition and management of an LVAD suction event, a rare but serious presentation encountered in the emergency department. This simulation can be successfully implemented either in situ, in an immersive simulation center, or off-site. This case could be represented by lower fidelity mannequins without the capabilities to provide learner tactile feedback of hemodynamics or airway, with a separate monitor device such as SimMon to display vital signs and digital media to demonstrate needed clinical images. The audio file of the low-flow alarm can be accessed and played by any device with internet access. The simulation benefits from embedded simulation participants to act as the bedside nurse and wife to provide history. This simulation included debriefing focused on a critical action checklist.

Research Methods

A working group of two simulation-trained faculty, a simulation fellow, and three senior emergency medicine residents chose and developed the simulation case. Two simulation-trained faculty implemented the pilot case series to gather feedback on performance against the critical action checklist. One simulation-trained faculty then facilitated two additional in situ sessions, again evaluating performance on the critical actions as well as content of the debrief discussion. That data was used to iteratively edit the presentation and dynamics of the case in preparation for the SIMposium case competition.

Results

During March 2022, in a three-case pilot in situ series, a total of 15 residents (five EM PGY4, four EM PGY3, five EM PGY2, one off-service PGY1) and two medical students (MS3) participated in the simulation case. Participant reactions were overwhelmingly positive, particularly from senior residents. The final version of the SIMposium case was held for a team of four emergency medicine residents from an alternate institution, all critical actions were met, and a discussion point arose regarding the reversal of anticoagulation in LVAD patients with acute GI bleed.

Discussion

Overall, this simulation was well received, effective, and easy to implement and translate to immersive, in situ, or offsite locations for the training of emergency medicine residents on the management of a high acuity, low-frequency event of LVAD device complication. Each debrief stimulated an excellent discussion regarding the general management of LVAD patients regarding initial assessment, arrhythmia, and distinguishing pathologies from device alarms. Our main takeaway from this simulation was the power of a case involving a critical and high acuity patient with LVAD which stimulated residents to engage in more robust discussions during debriefing, leading to broader clinical learning.

Topics

In situ simulation, simulation competition, LVAD, left ventricular assist device.

Readmission and Temporal Trends of Post-LVAD Placement Complications in Patients With End-Stage Heart Failure

INTRODUCTION

Approximately 5%-10% of heart failure (HF) patients progress to advanced stages. Left ventricular assist devices (LVADs) have emerged as a favored therapy for end-stage HF as destination therapy or as a bridge to heart transplantation. However, complications and provider expertise hinder their widespread use. To address this, the third-generation LVAD was introduced in late 2018 to enhance usability and reduce complications. We aimed to investigate the temporal trends in post-LVAD complications with the newest generation LVAD versus the previous version.

METHODS

We utilized the 2016-2020 Nationwide Readmission Database to identify patients ≥ 18 years of age with advanced HF implanted with an LVAD. Variables were determined using the International Classification of Diseases, Tenth revision codes. We compared patients through all years individually. In addition, we created two groups based on the implant year (2016-2018 and 2019-2020). The primary outcome was 30-day readmission, while secondary outcomes were complications and mortality rates. Multivariate analyses and descriptive bivariate analyses were performed. A value of p < 0.05 was considered statistically significant.

RESULTS

We identified 7975 patients (21.3% females), of which 17.1% (n = 1214) were readmitted within 30 days. Readmission rates were 18% (n = 778) for 2016-2018 and 16% (n = 435) for 2019-2020 (adjusted Wald test, p = 0.26). The 2019-2020 group exhibited a reduction in cardiac device complications (p = 0.024), cardiac tamponade (p = 0.009), and periprocedural circulatory complications (p = 0.014) in subgroup comparison (2016-2018 vs. 2019-2020). Despite these improvements, the mortality rate and hospital stay did not differ significantly between the two periods. No significant differences in mortality or LOS were observed between the two groups (adjusted Wald test, p > 0.05 in both).

CONCLUSIONS

Complications following LVAD placement continue to impede its broader adoption for advanced HF. Advancements in newer LVAD technology and improved provider expertise hold promise for increased utilization. Our study indicated a decline in some complications, including cardiac tamponade and cardiac device complications, including periprocedural circulatory ones, which may be attributed to newer device innovations. Further research is necessary to explore this correlation in greater depth.

British societies guideline on the management of emergencies in implantable left ventricular assist device recipients in transplant centres

An implantable left ventricular assist device (LVAD) is indicated as a bridge to transplantation or recovery in the United Kingdom (UK). The mechanism of action of the LVAD results in a unique state of haemodynamic stability with diminished arterial pulsatility. The clinical assessment of an LVAD recipient can be challenging because non-invasive blood pressure, pulse and oxygen saturation measurements may be hard to obtain. As a result of this unusual situation and complex interplay between the device and the native circulation, resuscitation of LVAD recipients requires bespoke guidelines. Through collaboration with key UK stakeholders, we assessed the current evidence base and developed guidelines for the recognition of clinical deterioration, inadequate circulation and time-critical interventions. Such guidelines, intended for use in transplant centres, are designed to be deployed by those providing immediate care of LVAD patients under conditions of precipitous clinical deterioration. In summary, the Joint British Societies and Transplant Centres LVAD Working Group present the UK guideline on management of emergencies in implantable LVAD recipients for use in advanced heart failure centres. These recommendations have been made with a UK resuscitation focus but are widely applicable to professionals regularly managing patients with implantable LVADs.

ADAMTS13 inhibition to treat acquired von Willebrand syndrome during mechanical circulatory support device implantation

BACKGROUND

Acquired von Willebrand syndrome (aVWS) is common in patients with mechanical circulatory support (MCS) devices. In these patients, the high shear stress in the device leads to increased shear-induced proteolysis of von Willebrand factor (VWF) by A Disintegrin And Metalloprotease with Thrombospondin type 1 repeats, number 13 (ADAMTS13). As a result, the high molecular weight (HMW) VWF multimers are lost, leading to a decreased VWF function and impaired hemostasis that could explain the bleeding complications that are frequently observed in these patients. To counteract this abnormal VWF degradation by ADAMTS13, we developed a novel targeted therapy, using an anti-ADAMTS13 monoclonal antibody (mAb) that inhibits the shear-induced proteolysis of VWF by ADAMTS13.

METHODS

Human or bovine blood was circulated through in vitro MCS device systems with either inhibitory anti-ADAMTS13 mAb 3H9 or 17C7 (20 μg/ml) or control anti-ADAMTS13 mAb 5C11 or phosphate buffered saline (PBS). VWF multimers and function (collagen binding activity) were determined at different time points. Next, Impella pumps were implanted in calves and the calves were injected with PBS and subsequently treated with mAb 17C7. VWF, ADAMTS13, and blood parameters were determined.

RESULTS

We demonstrated that blocking ADAMTS13 could prevent the loss of HMW VWF multimers in in vitro MCS device systems. Importantly, our antibody could reverse aVWS in a preclinical Impella-induced aVWS calf model.

CONCLUSION

Hence, inhibition of ADAMTS13 could become a novel therapeutic strategy to manage aVWS in MCS device patients.

Gastrointestinal Bleeding as a Complication in Continuous Flow Ventricular Assist Devices: A Systematic Review With Meta-Analysis

Background

The use of ventricular assist devices (VADs) has become predominant in this era of medicine. It is commonly used as a bridge to transplant, recovery and as a destination therapy for patients with severe heart failure, who are not responsive to maximum optimal management or ineligible for transplant. However, several complications are known to occur with the use of these devices. In this research, we will compare gastrointestinal bleeding in patients who used centrifugal flow versus axial flow VADs. We hope that the result of this meta-analysis and the review presented provide adequate information to future researchers, physicians and other healthcare professionals who are interested in this topic.

Methods

Published articles evaluated for inclusion were obtained from MEDLINE (PubMed), Cochrane, EBSCO, clinicaltrials.gov, and international clinical trials registry. This research was conducted according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. Procured articles were reviewed by two independent reviewers. Only randomized control trials and observational studies were used. Quality assessment was done with Cochrane Collaboration’s tool (RoB.2 with visualization through robviz) and Newcastle-Ottawa Scale (NOS). Data analysis was carried out with the use of R data analysis tool (version 4.0.0; release date: April 24th, 2020).

Results

At the end of this meta-analysis, the occurrence of gastrointestinal bleeding was not significantly different between both groups; with odds ratio (OR): 0.81; 95% confidence interval (CI): 0.65 - 1.00; P value = 0.05. Between-study variance (Tau-squared) was zero (0), standard error (SE) = 0.06. The degree of heterogeneity measured with I-squared statistic was 0% (minimal). Egger’s regression test was not statistically significant, P = 0.93. Symmetry of distribution was observed on the funnel plot. Trim and fill analysis showed no missing studies on the left; SE = 1.68.

Conclusions

The result obtained from this research indicates that the occurrence of gastrointestinal bleeding is not significantly different in both groups of patients, irrespective of the type of continuous flow VAD used. Although, the study sample used in this meta-analysis was limited.