Mechanical circulatory support

A multidisciplinary approach for the emergency care of patients with left ventricular assist devices: A practical guide

The use of a left ventricular assist device (LVAD) as a bridge-to-transplantation or destination therapy to support cardiac function in patients with end-stage heart failure (HF) is increasing in all developed countries. However, the expertise needed to implant and manage patients referred for LVAD treatment is limited to a few reference centers, which are often located far from the patient's home. Although patients undergoing LVAD implantation should be permanently referred to the LVAD center for the management and follow-up of the device also after implantation, they would refer to the local healthcare service for routine assistance and urgent health issues related to the device or generic devices. Therefore, every clinician, from a bigger to a smaller center, should be prepared to manage LVAD carriers and the possible risks associated with LVAD management. Particularly, emergency treatment of patients with LVAD differs slightly from conventional emergency protocols and requires specific knowledge and a multidisciplinary approach to avoid ineffective treatment or dangerous consequences. This review aims to provide a standard protocol for managing emergency and urgency in patients with LVAD, elucidating the role of each healthcare professional and emphasizing the importance of collaboration between the emergency department, in-hospital ward, and LVAD reference center, as well as algorithms designed to ensure timely, adequate, and effective treatment to patients with LVAD.

Asymptomatic ventricular fibrillation in continuous flow left-ventricular assist device

Left ventricular assist devices (LVADs) have increased survival for heart failure patients. Individuals with LVADs are a growing patient population with frequent complications and Emergency Department (ED) visits. A 50-year-old female presented to the ED due to a low flow alarm on her LVAD. Upon arrival in the ED she was noted to be in ventricular fibrillation. She was defibrillated with restoration to normal sinus rhythm and was started on amiodarone. An implantable cardiac defibrillator was placed during hospital admission. Amiodarone was continued as an outpatient. Patients with continuous flow LVADs can be in dysrhythmias including ventricular tachycardia and ventricular fibrillation and remain relatively asymptomatic. We present a rare case of a patient with an LVAD and ventricular fibrillation who was completely asymptomatic in the ED.

Retrospective evaluation of emergency department admissions in patients with ventricular assist device

Background:

Ventricular assist devices, improve morbidity and survival in patients with end-stage heart failure.

Objectives:

To evaluate the major causes of emergency department admissions in patients with ventricular assist device support.

Methods:

The charts of 200,000 adult patients who presented to our emergency department between January 2016 and January 2018 were reviewed retrospectively. A total of 444 emergency department visits made by 99 patients with ventricular assist device were included in the study.

Results:

The annual incidence of emergency department admissions of patients with ventricular assist device was 0.1%. The mean age was 55.5 ± 11.1 years and 85.9% of the study population were men. The most commonly encountered diagnoses were abnormal international normalized ratio or international normalized ratio follow-up (18.2%); heart failure, non-specific chest pain, and chronic obstructive pulmonary disease (15.3%); minor/major bleeding (12.1%); neurological disorders such as ischemic stroke, transient ischemic attack, vertigo, migraine, and syncope (11.2%); non-device related infections (10.8%); ventricular tachycardia/fibrillation episode (8.5%); musculoskeletal disorders (7.2%); and device-related complications such as driveline infection and pump thrombosis (6.3%). Of the patients with bleeding, 31.1% had intracranial bleeding, 31.1% had epistaxis, 24% had gastrointestinal bleeding, 11.1% had hematuria, and 1.8% had gingival hemorrhage. Of the 15 patients who died, 73.3% were diagnosed with intracranial hemorrhage.

Conclusion:

Even though the mortality rates of patients with ventricular assist device tends to decrease, these patients still have significant morbidity due to the increase in the prevalence of ventricular assist device use. Except for device-related problems, emergency department management of this patient group does not differ much from other patient groups. As early diagnosis of any device-related problems is mandatory for decreasing mortality, emergency department physicians should be familiar with mechanical support systems.

Left ventricular assist devices and their complications: A review for emergency clinicians

INTRODUCTION

End stage heart failure is associated with high mortality. However, recent developments such as the ventricular assist device (VAD) have improved patient outcomes, with left ventricular assist devices (LVAD) most commonly implanted.

OBJECTIVE

This narrative review evaluates LVAD epidemiology, indications, normal function and components, and the assessment and management of complications in the emergency department (ED).

DISCUSSION

The LVAD is a life-saving device in patients with severe heart failure. While first generation devices provided pulsatile flow, current LVAD devices produce continuous flow. Normal components include the pump, inflow and outflow cannulas, driveline, and external controller. Complications related to the LVAD can be divided into those that are LVAD-specific and LVAD-associated, and many of these complications can result in severe patient morbidity and mortality. LVAD-specific complications include device malfunction/failure, pump thrombosis, and suction event, while LVAD-associated complications include bleeding, cerebrovascular event, infection, right ventricular failure, dysrhythmia, and aortic regurgitation. Assessment of LVAD function, patient perfusion, and mean arterial pressure is needed upon presentation. Electrocardiogram and bedside ultrasound are key evaluations in the ED. LVAD evaluation and management require a team-based approach, and consultation with the LVAD specialist is recommended.

CONCLUSION

Emergency clinician knowledge of LVAD function, components, and complications is integral in optimizing care of these patients.

Percutaneous assist devices in acute myocardial infarction with cardiogenic shock: Review, meta-analysis

AIM: To assess the impact of percutaneous cardiac support in cardiogenic shock (CS) complicating acute myocardial infarction (AMI), treated with percutaneous coronary intervention.

METHODS: We selected all of the studies published from January 1^st, 1997 to May 15^st, 2015 that compared the following percutaneous mechanical support in patients with CS due to AMI undergoing myocardial revascularization: (1) intra-aortic balloon pump (IABP) vs Medical therapy; (2) percutaneous left ventricular assist devices (PLVADs) vs IABP; (3) complete extracorporeal life support with extracorporeal membrane oxygenation (ECMO) plus IABP vs IABP alone; and (4) ECMO plus IABP vs ECMO alone, in patients with AMI and CS undergoing myocardial revascularization. We evaluated the impact of the support devices on primary and secondary endpoints. Primary endpoint was the inhospital mortality due to any cause during the same hospital stay and secondary endpoint late mortality at 6-12 mo of follow-up.

RESULTS: One thousand two hundred and seventy-two studies met the initial screening criteria. After detailed review, only 30 were selected. There were 6 eligible randomized controlled trials and 24 eligible observational studies totaling 15799 patients. We found that the inhospital mortality was: (1) significantly higher with IABP support vs medical therapy (RR = +15%, P = 0.0002); (2) was higher, although not significantly, with PLVADs compared to IABP (RR = +14%, P = 0.21); and (3) significantly lower in patients treated with ECMO plus IABP vs IABP (RR = -44%, P = 0.0008) or ECMO (RR = -20%, P = 0.006) alone. In addition, Trial Sequential Analysis showed that in the comparison of IABP vs medical therapy, the sample size was adequate to demonstrate a significant increase in risk due to IABP.

CONCLUSION: Inhospital mortality was significantly higher with IABP vs medical therapy. PLVADs did not reduce early mortality. ECMO plus IABP significantly reduced inhospital mortality compared to IABP.

Protocols for uncontrolled donation after circulatory death: a systematic review of international guidelines, practices and transplant outcomes

INTRODUCTION

A chronic shortage of organs remains the main factor limiting organ transplantation. Many countries have explored the option of uncontrolled donation after circulatory death (uDCD) in order to expand the donor pool. Little is known regarding the variability of practices and outcomes between existing protocols. This systematic review addresses this knowledge gap informing policy makers, researchers, and clinicians for future protocol implementation.

METHODS

We searched MEDLINE, EMBASE, and Google Scholar electronic databases from 2005 to March 2015 as well as the reference lists of selected studies, abstracts, unpublished reports, personal libraries, professional organization reports, and government agency statements on uDCD. We contacted leading authors and organizations to request their protocols and guidelines. Two reviewers extracted main variables. In studies reporting transplant outcomes, we added type, quantity, quality of organs procured, and complications reported. Internal validity and the quality of the studies reporting outcomes were assessed, as were the methodological rigour and transparency in which a guideline was developed. The review was included in the international prospective register of systematic reviews (Prospero, CRD42014015258).

RESULTS

Six guidelines and 18 outcome studies were analysed. The six guidelines are based on limited evidence and major differences exist between them at each step of the uDCD process. The outcome studies report good results for kidney, liver, and lung transplantation with high discard rates for livers.

CONCLUSIONS

Despite procedural, medical, economic, legal, and ethical challenges, the uDCD strategy is a viable option for increasing the organ donation pool. Variations in practice and heterogeneity of outcomes preclude a meta-analysis and prevented the linking of outcomes to specific uDCD protocols. Further standardization of protocols and outcomes is required, as is further research into the role of extracorporeal resuscitation and other novel therapies for treatment of some refractory cardiac arrest. It is essential to ensure the maintenance of trust in uDCD programs by health professionals and the public.