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Introduction: Compared with the left ventricle (LV), the right ventricle (RV) is less suited for evaluation by echocardiography (ECHO). Nevertheless, RV ECHO-assessment has currently emerged as an important diagnostic tool with meaningful prognostic value and essential contribution to therapeutic decisions. Although significant progress has been made, including generation of higher-quality normative data, validation of several two-dimensional measurements and improvements in three-dimensional ECHO-techniques, many challenges in RV ECHO-assessment still persist. Areas covered: This review discusses the particular challenges and limits in obtaining accurate measurements of RV anatomical and functional parameters and focuses primarily on the difficulties in proper interpretation of the highly load dependent RV ECHO-parameters which complicates the use of this valuable diagnostic and surveillance technique. Expert commentary: There is increasing evidence that RV assessment in relation with its actual loading conditions by ECHO-derived composite variables, which either incorporate a certain functional parameter and load, or incorporate measures which reflect the relationship between RV dilation and RV load, considering also the right atrial pressure (i.e. 'load adaptation index'), is particularly suited for clinical decision-making. Load dependency of RV ECHO-parameters must be taken into consideration especially in patients with advanced RV dysfunction scheduled for LV assist device implantation or lung transplantation. [ABSTRACT FROM AUTHOR]

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Severe right ventricular (RV) failure is more likely reversible than similar magnitudes of left ventricular (LV) failure and, because reversal of both adaptive remodeling and impaired contractility require most often only short periods of support, the use of temporary RV assist devices (t-RVADs) can be a life-saving therapy option for many patients. Although increased experience with t-RVADs and progresses made in the development of safer devices with lower risk for complications has improved both recovery rate of RV function and patient survival, the mortality of t-RVAD recipients can still be high but it depends mainly on the primary cause of RV failure (RVF), the severity of end-organ dysfunction, and the timing of RVAD implantation, and much less on adverse events and complications related to RVAD implantation, support, or removal. Reduced survival of RVAD recipients should therefore not discourage appropriate application of RVADs because their underuse further reduces the chances for RV recovery and patient survival. The article reviews and discusses the challenges related to the pre-implant and post-implant decision-making processes aiming to get best possible therapeutic results. Special attention is focused on pre-implant RV assessment and prediction of RV improvement during mechanical unloading, patient selection for t-RVAD therapy, assessment of unloading-promoted RV recovery, and prediction of its stability after RVAD removal. Particular consideration is also given to prediction of RVF after LVAD implantation which is usually hampered by the complex interactions between the different risk factors related indirectly or directly to the RV potential for reverse remodeling and functional recovery. [ABSTRACT FROM AUTHOR]

Abstract: The HeartWare HVAD is a small, third generation continuous flow pump that is intracorporeally placed for support of a failing ventricle in adult patients. This device is small in size when compared to other left ventricular assist devices and can therefore be used in smaller sized pediatric patients. We present our initial experience using the HVAD as a bridge to heart transplantation in the pediatric population. We performed a retrospective, single center, nonrandomized review of 17 pediatric patients who underwent HVAD implantation between June 2013 and March 2016. The primary endpoints evaluated in this study were overall survival to heart transplantation, ongoing device support, or death. In this patient cohort, nine (53%) of 17 patients were male. The median age of the patients was 13.4 ± 3.8 (range 5–17) years. The median body surface area was 1.4 ± 0.4(0.7–2) m2. Etiologies of heart failure requiring HVAD support were dilated cardiomyopathy (n = 8), myocarditis (n = 5) and noncompaction cardiomyopathy (n = 4). The overall mean length of HVAD support was 254 ± 298 (range 2–804) days. A successful outcome (bridge to transplant and ongoing mechanical support) was achieved in 13 patients (76.5%). Of the 13 patients, nine (69.2%) were bridged to heart transplantation and four continue to receive support (30.7%) and are eligible for transplantation. Post‐transplant survival has been 100%, with a mean follow‐up of 296 ± 264.5 (range 18–785) days. The most common complication was pump thrombosis (23.5%) in follow‐up. Four patients (23.5%) experienced no complications. The HVAD continuous flow ventricular assist device can be safely used to bridge pediatric patients to cardiac transplantation. Favorable outcomes of this device are comparable to the adult population. This analysis demonstrated safe and effective implantation of the HVAD System in a child with a BSA of 0.7 m2. [ABSTRACT FROM AUTHOR]

Background Primary outcomes analysis of the Multicenter Study of MagLev Technology in Patients Undergoing MCS Therapy With HeartMate 3 (MOMENTUM 3) trial short-term cohort demonstrated a higher survival rate free of debilitating stroke and reoperation to replace/remove the device (primary end-point) in patients receiving the HeartMate 3 (HM3) compared with the HeartMate (HMII). In this study we sought to evaluate the individual and interactive effects of pre-specified patient subgroups (age, sex, race, therapeutic intent [bridge to transplant/bridge to candidacy/destination therapy] and severity of illness) on primary end-point outcomes in MOMENTUM 3 patients implanted with HM3 and HMII devices. Methods Cox proportional hazard models were used to analyze patients enrolled in the “as-treated cohort” ( n = 289) of the MOMENTUM 3 trial to: (1) determine interaction of various subgroups on primary end-point outcomes; and (2) identify independent variables associated with primary end-point success. Results Baseline characteristics were well balanced among HM3 ( n = 151) and HMII ( n = 138) cohorts. No significant interaction between the sub-groups on primary end-point outcomes was observed. Cox multivariable modeling identified age (≤65 years vs >65 years, hazard ratio 0.42 [95% confidence interval 0.22 to 0.78], p = 0.006]) and pump type (HM3 vs HMII, hazard ratio 0.53 [95% confidence interval 0.30 to 0.96], p = 0.034) to be independent predictors of primary outcomes success. After adjusting for age, no significant impact of sex, race, therapeutic intent and INTERMACS profiles on primary outcomes were observed. Conclusions This analysis of MOMENTUM 3 suggests that younger age (≤65 years) at implant and pump choice are associated with a greater likelihood of primary end-point success. These findings further suggest that characterization of therapeutic intent into discrete bridge-to-transplant and destination therapy categories offers no clear clinical advantage, and should ideally be abandoned. [ABSTRACT FROM AUTHOR]

As treatment options in modern medicine continue to expand, physicians globally have witnessed a veritable explosion in the utility of therapeutic devices. Particularly within the spheres of cardiology and critical care medicine, a plethora of devices are now available with an ever-increasing range of clinical indications. Additionally, the advent of transcatheter-mounted devices has enabled patients unsuitable for more invasive procedures to benefit from intervention, thereby greatly expanding the cohort of device-eligible patients. However, despite advances in design and materials, as well as pharmacological prophylaxis, hemostatic complications continue to plague device recipients, contributing to morbidity and mortality. Elucidating the complex interplay between components of the hemostatic system and cardiac devices has been the subject of much recent research, with greater focus on the coagulation cascade and device-induced perturbations. However, less is known about impact of mechanical surfaces on platelets and the resultant clinical complications, both hemorrhagic and thrombotic. This review will focus on exploring the pathobiology of platelet-surface interactions, contextualized within the wider hemostatic system, with a focus on the increasingly utilized technologies of transcatheter aortic-valve implantation, ventricular assist devices, and extracorporeal membrane oxygenation. [ABSTRACT FROM AUTHOR]

Background: Device indications have changed for placement of continuous-flow left ventricular assist devices (CF-LVADs). We performed a multicenter analysis evaluating temporal variations in outcomes after CF-LVAD implantation.Methods& Results: We retrospectively defined 3 time intervals to reflect changes in CF-LVAD technology (period 1, 2004-2009; period 2, 2010-2012; and period 3, 2012-2014). A total of 1,064 patients (Heartmate II [HMII] = 835; Heartware [HVAD] = 229) underwent CF-LVAD implantation from May 2004 to October 2014. Device utilization was different between periods: period 1: HMII = 134 (100%); period 2: HMII = 480 (88%) and HW = 63 (12%); and period 3: HMII = 221 (57%) and HW = 166 (43%); P < .001. Despite few baseline group differences, adjusted survivals were similar among the time periods (P = .96). Adjusted multivariable analysis revealed age (per 10-year increase) and Interagency Registry for Mechanically Assisted Circulatory Support category (1 vs all others) as the only independent predictors of mortality: P < .001 and P = .008, respectively. Furthermore, it also showed the later periods to be at an increased risk of adverse events: 1) pump thrombosis (periods 2 and 3); and 2) gastrointestinal bleeding (period 3).Conclusions: Despite significant differences in device types, indications, and patient characteristics, post-implantation survivals were similar across time intervals. The most recent cohort seems to be at an increased risk of gastrointestinal bleeding and pump thrombosis. [ABSTRACT FROM AUTHOR]

Introduction: Through concerted endeavours in the fields of surgery, medicine, and biomedical engineering, patronized by government and industry, ventricular assist devices have become an established surgical treatment to support the failing heart, which could easily and simply surpass the frequency of heart transplantation. Be it as it may, complications and adverse events have unfolded, and these facilitated the way to newer biomedically-engineered pump designs in search of the perfect support for a failing heart. Areas covered: This review focuses on the evolution of the continous-flow ventricular assist device as an accepted mode of treatment in advanced heart failure, as a bridge to myocardial recovery, as a bridge to heart transplantation and as a permanent therapy, with its attendant complications and long-term outcome. Expert commentary: Continuous flow devices offer improved durability, less surgical trauma due to their smaller size, high-energy efficiency, and lower thrombogenicity, regardless of administration of single or dual anti-thrombotic therapy. These benefits translate into better survival, lower frequency of adverse events, improved quality of life and higher functional capacity of patients. Through ceaseless innovations and technology, newer pumps have been developed; however, none has been proven to be superior over the others. [ABSTRACT FROM AUTHOR]

Background Quantifying quality of life (QoL) after left ventricular assist device (LVAD) remains challenging. Heart failure (HF)-specific health status measures are ideal for assessing symptoms of HF; however, if patients’ QoL is limited by other factors, they may experience improved HF-specific QoL but no concurrent improvement in generic QoL. We sought to examine and predict discrepancies between disease-specific and generic QoL measures after LVAD. Methods We examined HF-specific and generic QoL with the Kansas City Cardiomyopathy Questionnaire (KCCQ) and EuroQol-5D Visual Analog Scale (VAS), respectively, among 1,888 patients with advanced heart failure who underwent LVAD implantation from 2012 to 2014 as part of the INTERMACS registry. Results Both measures showed substantial improvement, on average, at 6 months after LVAD, with mean changes of 32.7 ± 25.0 and 27.6 ± 27.4, respectively. Among the 1,539 patients (81.5%) with moderate/large improvement in KCCQ, 334 (21.7%) had discordant changes in generic QoL (i.e., VAS did not substantially increase despite improvement in KCCQ). In a multivariable logistic regression model, baseline VAS score was the strongest predictor of KCCQ-VAS discordance, whereas post-LVAD complications were not significant predictors of discordance. Conclusions Most patients have major improvements in both HF-specific and generic QoL after LVAD implantation, and discordance in these measures after LVAD is uncommon. When it did occur, discordance was primarily observed in patients who reported good generic QoL on the VAS before LVAD (despite substantial impairment due to congestive HF). These results support the continued use of HF-specific health status measures to monitor QoL before and after LVAD implantation. [ABSTRACT FROM AUTHOR]

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Background: Cardiac remodeling describes the molecular, cellular, and interstitial changes that cause the ventricle to develop pathologic geometry as heart failure progresses. Reverse remodeling, or the healing of a failing heart, leads to improved mortality and quality of life. Findings: Therapies that lead to reverse remodeling include medications such as β-blockers and angiotensin-converting enzyme inhibitors; cardiac resynchronization therapy with biventricular pacing; and mechanical support with left ventricular assist devices. Conclusions: Further study is needed to better predict which patients will benefit most from these therapies and will then go on to experience reverse remodeling and myocardial recovery.

Background: Bleeding is an important and common complication of left ventricular assist devices (LVADs). One of the common causes of gastrointestinal bleeding is arteriovenous malformations. However, the source of bleeding is often hard to identify. Thalidomide is efficacious in treatment of gastrointestinal (GI) bleeding in non-LVAD patients. We report our experience of the use of thalidomide in the treatment of GI bleeding in four patients with LVAD.Method and Results: Four patients who had recurrent GI bleeding from May 2009 to December 2014 were started on thalidomide. All of them responded to treatment and had no further gastrointestinal bleeding while on thalidomide. One patient developed constipation, requiring thalidomide to be stopped. Another patient developed symptomatic neuropathy, that resolved with reduction of dosage.Conclusion: Thalidomide appears safe and efficacious in LVAD patients with recurrent gastrointestinal bleeding. [ABSTRACT FROM AUTHOR]

Thrombus formation is a major adverse event affecting patients implanted with ventricular assist devices (VADs). Despite anti-thrombotic drug administration, thrombotic events remain frequent within the first year post-implantation. Platelet activation (PA) is an essential process underling thrombotic adverse events in VAD systems. Indeed, abnormal shear forces, correlating with specific flow trajectories of VADs, are strong agonists mediating PA. To date, the ability to determine efficacy of anti-platelet (AP) agents under shear stress conditions is limited. Here, we present a novel microfluidic platform designed to replicate shear stress patterns of a clinical VAD, and use it to compare the efficacy of two AP agents in vitro. Gel-filtered platelets were incubated with i) acetylsalicylic acid (ASA) and ii) ticagrelor, at two different concentrations (ASA: 125 and 250 µM; ticagrelor: 250 and 500 nM) and were circulated in the VAD-emulating microfluidic platform using a peristaltic pump. GFP was collected after 4 and 52 repetitions of exposure to the VAD shear pattern and tested for shear-mediated PA. ASA significantly inhibited PA only at 2-fold higher concentration (250 µM) than therapeutic dose (125 µM). The effect of ticagrelor was not dependent on drug concentration, and did not show significant inhibition with respect to untreated control. This study demonstrates the potential use of microfluidic platforms as means of testing platelet responsiveness and AP drug efficacy under complex and realistic VAD-like shear stress conditions. [ABSTRACT FROM AUTHOR]

The pediatric use of pneumatic ventricular assist devices (VADs) as a bridge to heart transplant still suffers for short-term major complications such as bleeding and thromboembolism. Although numerical techniques are increasingly exploited to support the process of device optimization, an effective virtual benchmark is still lacking. Focusing on the 12 cc Penn State pneumatic VAD, we developed a novel fluid-structure interaction (FSI) model able to capture the device functioning, reproducing the mechanical interplay between the diaphragm, the blood chamber, and the pneumatic actuation. The FSI model included the diaphragm mechanical response from uniaxial tensile tests, realistic VAD pressure operative conditions from a dedicated mock loop system, and the behavior of VAD valves. Our FSI-based benchmark effectively captured the complexity of the diaphragm dynamics. During diastole, the initial slow diaphragm retraction in the air chamber was followed by a more rapid phase; asymmetries were noticed in the diaphragm configuration during its systolic inflation in the blood chamber. The FSI model also captured the major features of the device fluid dynamics. In particular, during diastole, a rotational wall washing pattern is promoted by the penetrating inlet jet with a low-velocity region located in the center of the device. Our numerical analysis of the 12 cc Penn State VAD points out the potential of the proposed FSI approach well resembling previous experimental evidences; if further tested and validated, it could be exploited as a virtual benchmark to deepen VAD-related complications and to support the ongoing optimization of pediatric devices. [ABSTRACT FROM AUTHOR]

Copyright of Zeitschrift für Herz-, Thorax- und Gefaesschirurgie is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Introduction: Improved survival following single ventricle palliation has led to a large population of patients with a univentricular circulation, many of whom develop heart failure. Increasing experience with ventricular assist devices (VAD) in children has paved the way for VAD support in those with failing univentricular circulation. Areas covered: The use of VADs to support the failing univentricular circulation is a relatively new concept. Most studies have focused on supporting patients with the failing systemic ventricle. There are limited reports of VAD support of the pulmonary circulation in patients with Fontan failure despite preserved ventricular function. None of the current VADs have been designed to support the pulmonary circulation. Novel low-pressure, high-flow pumps, specifically designed to support the pulmonary circulation, are under development. Expert commentary: The failing univentricular circulation is one of the great challenges in the field of congenital heart disease. While current VADs are designed to support the systemic circulation, many patients require support of the pulmonary circulation. A fully implantable VAD for support of the pulmonary circulation as destination therapy would be beneficial for patients with preserved systolic function, but must have low energy requirements, negligible risk of stroke and low risk of device thrombosis and failure. [ABSTRACT FROM PUBLISHER]

Objective The purpose of this article was to review the principal mechanisms of three types of heart assist devices, to explore their haemodynamic impacts on spectral Doppler and to discuss the associated challenges in diagnostic ultrasound. Conclusion Heart assist devices are used in patients with advanced heart failure as bridge to transplantation or destination therapy. The arterial Doppler waveform features can be altered after the implantation of the devices. A continuous-flow device converts the arterial waveform into a venous-like waveform with a mean velocity that can be used in stenosis evaluation. When the pulsatile device produces extra pulses between the natural heartbeats, together they produce serrated arterial waveforms. When the pulsatile device serves as the only pumping source, the arterial waveforms are similar to the natural ones. Colour Doppler features are maintained despite all the spectral Doppler changes. These devices can affect both ultrasound scanning and interpretation. Therefore, it is essential to understand the principal mechanisms of these devices and their haemodynamic impacts so that an accurate ultrasound diagnosis can be made. [ABSTRACT FROM AUTHOR]

The medical burden of heart failure (HF) has spurred interest in clinicians and scientists to develop therapies to restore the function of a failing heart. To advance this agenda, the National Heart, Lung, and Blood Institute (NHLBI) convened a Working Group of experts on June 2-3, 2016, in Bethesda, Maryland, to develop recommendations for the NHLBI aimed at advancing the science of cardiac recovery in the setting of mechanical circulatory support (MCS). MSC devices effectively reduce volume and pressure overload that drives the cycle of progressive myocardial dysfunction, thereby triggering structural and functional reverse remodeling. Research in this field could be innovative in many ways, and the Working Group specifically discussed opportunities associated with genome-phenome systems biology approaches, genetic epidemiology, bioinformatics and precision medicine at the population level, advanced imaging modalities including molecular and metabolic imaging, and developing minimally invasive surgical and percutaneous bioengineering approaches. These new avenues of investigations could lead to new treatments that target phylogenetically conserved pathways involved in cardiac reparative mechanisms. A central point that emerged from the NHLBI Working Group meeting was that the lessons learned from the MCS investigational setting can be extrapolated to the broader HF population. With the precedents set by the significant impact of studies of other well controlled and tractable subsets on larger populations, such as the genetic work in both cancer and cardiovascular disease, the work to improve our understanding of cardiac recovery and resilience in MCS patients could be transformational for the greater HF population. [ABSTRACT FROM AUTHOR]

Introduction: A modern ventricular assist device (VAD) system comprises an implantable rotary blood pump and external components located outside the patient’s body: a wearable controller connected to the pump via a percutaneous cable, wearable rechargeable batteries, battery charger, alternating- and direct-current power supplies, and a hospital device to control and monitor the system. If the blood pump is the ‘heart’ of a VAD system, the controller is its ‘brain.’ The controller drives the pump’s electrical motor; varies the pump speed or flow based on user commands or feedback signals; collects, processes, and stores data; performs self-diagnostics; transmits to and receives data from other system components, i.e., hospital monitor and batteries; and provides various types of user interface – audible, visual, and tactile. Areas covered: Here we describe the essential functions and basic design of the VAD external controller and give our views on the future of this technology. Expert commentary: Controllers for VAD systems are crucial to their successful operation. The current clinically available system comprises an external power supply and patient-friendly controller unit. Future controller solutions may enable remote hospital monitoring, more intuitive system interface, and the potential to use a single controller to automatically control a biventricular assist device configuration. [ABSTRACT FROM AUTHOR]

OBJECTIVES: Impaired binding of Von Willebrand factor (VWF) to platelets and to collagen due to acquired Von Willebrand syndrome (AVWS) is associated with support from a ventricular assist device (VAD) and can contribute to bleeding tendencies in patients with VADs. The onset of AVWS has been shown to occur immediately after VAD implantation. Our aim was to determine long-term data on AVWS in VAD patients. METHODS: We analysed 278 data sets of 74 patients on HeartMate II (HMII) support for 3-80 months after implantation (11.2 ± 12.1, median 6.3 months.). Ristocetin cofactor activity (VWF:RCo), collagen binding capacity (VWF:CB), VWF antigen (VWF:Ag) and the ratios of VWF:RCo/VWF:Ag and VWF:CB/VWF:Ag were determined. Further, the presence of high molecular weight (HMW) multimers of VWF was investigated. RESULTS: Abnormally low values of VWF:RCo/VWF:Ag and VWF:CB/VWF:Ag were found in 69% and 97% of blood samples, respectively. Only ten of 181 multimer analyses showed a normal pattern, and HMW multimers were present in both specimens in only one of the 74 patients. No significant changes in these parameters were observed over time. The VWF:CB/VWF:Ag ratio correlated with the multimer patterns, whereas the VWF:RCo/VWF:Ag ratio seemed to be less sensitive for AVWS. CONCLUSION: Our data indicate that AVWS is a typical phenomenon in patients with VAD support and that there are no timedependent changes in these parameters apparent in most patients on long-term support with HMII. [ABSTRACT FROM AUTHOR]

Background. B-type natriuretic peptide (BNP) is a strong predictor of prognosis in chronic heart failure. We aimed to evaluate the clinical correlates and interpretation of BNP monitoring in LVAD out-patient recipients. Methods. We performed a prospective study in 136 individuals after HeartMate II LVAD implantation. During follow-up they were divided into group A (severe adverse events requiring hospitalisation), group B (mild to moderate adverse events) and group C (an uneventful course). BNP was measured pre-implant, at the first out-patient visit, and then every 2 months. We identified the lowest level, and the level at the clinical event and/or the highest value in patients without clinical events (BNP peak). Results. During a median follow-up of 298 days, 8 patients (6%) died, 21 patients (15%) experienced a severe adverse event (group A) and 38 patients (28%) had other adverse event (group B). Both the absolute value of BNP peak and its percentage values relative to pre-implant, first visit and minimum BNP had similar areas under the curve (AUC) to identify individuals with adverse events (group A and B) from group C. The performance of BNP peak rose from detection of infection to diagnosis of heart failure and culminated in individuals with pump thrombosis (AUC 0.68 vs. 0.75 vs. 0.93). Conclusions. Serial measurement of BNP in outpatients with LVAD correlates with the occurrence of adverse events. Assessment of absolute values of BNP peak seems to have a similar accuracy to analysis of intra-individual variation of BNP and it is more practical. [ABSTRACT FROM AUTHOR]

We introduce and investigate a method to identify the feature point of an electrocardiogram (ECG) to provide real-time and accurate trigger signals for pulsatile ventricular assist devices (PVADs). An important part of this method is an improved data processing algorithm, in which a differential calculator and another a low-pass filtering were added to avoid drift in the original signal and systematically delay caused by physical devices. The method was systematically illustrated in this article and a test-setup was built based on the LabVIEW program development environment. Both simulations and experiments were carried out to demonstrate the merits of the method. Simulated results based on four typical pathological ECG signals confirm the robustness and adaptability of this method. Experimental results verified the benefits of this method with regard to increased accuracy that can pick up the interested signal accurately in a degree of larger than 99%. This improved technology proposed in this research will be greatly beneficial to simultaneous triggering in VADs and eventually to the heart failure recovery. [ABSTRACT FROM PUBLISHER]

To describe the multidisciplinary rehabilitation management of two patients status post LVAD implantation when complicated by right sided heart failure and RVAD placement. The design of the study was a case study. The setting of this case study was a 746-bed tertiary hospital in Allentown, PA. Both patients were admitted to heart failure service and treated by cardiopulmonary service line which consists of physical therapy, occupation therapy, and phase one cardiac rehabilitation. Two patients were included in this case study. Patients were selected based on the criteria of requiring RVAD support following new LVAD implantation. Treatment program consisted of bed mobility, transfer training, balance training, muscle strengthening, LVAD management tasks, assisted cough/deep breathing techniques, energy conservation education, activities of daily living management, and progressive ambulation. Outcome measures performed included the Boston University AM-PAC "6-clicks" Inpatient Basic Mobility and Daily Activity Short Forms, six minute walk test, Tinetti Gait and Balance Assessment, grip strength measurement, Montreal Cognitive Assessment, and Kansas City Cardiomyopathy Questionnaire. Case One received 18 PT sessions, 19 OT sessions, and 19 CR sessions post LVAD implantation during acute care stay. Of these sessions, nine were completed in the presence of RVAD. Patient's AM-PAC score improved from 7/24 to 17/24 on Basic Mobility Short Form and 10/24 to 18/24 on Daily Activity Short Form. Patient was discharged to the acute inpatient rehabilitation center on hospital day 56. Case Two received 23 PT sessions, 19 OT sessions, and 8 CR sessions post LVAD implantation. 15 sessions were completed in the presence of RVAD. Improvement in AM-PAC score was documented from 6/24 to 24/24 on both Basic Mobility and Daily Activity Short Form. The progression in functional status allowed this patient to be discharged directly home with home services on hospital day 45. This case study demonstrates that rehab services can be safety implemented following LVAD implant complicated by RVAD placement when the appropriate multidisciplinary team approach is utilized. No financial disclosures or conflicts of interest. [ABSTRACT FROM AUTHOR]

Most of the existing hemolysis mechanism studies are carried out on the macro flow scale. They assume that the erythrocyte membranes with different loads will suffer the same damage, which obviously has limitations. Thus, exploring the hemolysis mechanism through the macroscopic flow field information is a tough challenge. In order to further understand the non-physiological shear hemolysis phenomenon at the cell scale, this study used the coarse-grained erythrocytes damage model at the mesoscopic scale based on the transport dissipative particle dynamics (tDPD) method. Combined with computational fluid dynamics the hemolysis of scalarized shear stress ( τ ) in the clearance of "Impella 5.0" was evaluated under the Lagrange perspective and Euler perspective. The results from the Lagrange perspective showed that the change rate of scaled shear stress ( τ ˙ ) was the most critical factor in damaging RBCs in the rotor region of "Impella 5.0"and other transvalvular micro-axial blood pumps. Then, we propose a dimensionless number D k with time integration based on τ ˙ to evaluate hemolysis. The Dissipative particle dynamics simulation results are consistent with the D k evaluation results, so τ ˙ may be an important factor in the hemolysis of VADs. Finally, we tested the hemolysis of 30% hematocrit whole blood in the "Impella 5.0" shroud clearance from the Euler perspective. Relevant results indicate that because of the wall effect, the RBCs near the impeller side are more prone to damage, and most of the cytoplasm is also gathered at the rotor side., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2023 Xu, Chen, Hao, He and Zhang.)

Advanced heart failure (AHF) therapy allocation is vulnerable to bias related to subjective assessments and poor group dynamics. Our objective was to determine whether an implementation strategy for AHF team members could feasibly contribute to organizational and culture change supporting equity in AHF allocation. Using a pretest-posttest design, the strategy included an 8-week multicomponent training on bias reduction, standardized numerical social assessments, and enhanced group dynamics at an AHF center. Evaluations of organizational and cultural changes included pretest-posttest AHF team member surveys, transcripts of AHF meetings to assess group dynamics using a standardized scoring system, and posttest interviews guided by a framework for implementing a complex strategy. Results were analyzed with qualitative descriptive methods and Brunner-Munzel tests for relative effect (RE, RE >0.5 signals posttest improvement). The majority of survey metrics revealed potential benefit with RE >0.5. REs were >0.5 for 5 of 6 group dynamics metrics. Themes for implementation included (1) promoting equitable distribution of scarce resources, (2) requiring a change in team members' time investment to correct bias and change the meeting structure, (3) slowing and then accelerating the allocation process, and (4) adaptable beyond AHF and reinforceable with semi-annual trainings. An implementation strategy for AHF equity demonstrated the feasibility for organizational and culture changes., (Copyright © 2023 American Society of Transplantation & American Society of Transplant Surgeons. Published by Elsevier Inc. All rights reserved.)

Purpose: The aim of this study is to investigate the efficacy of adaptation of right ventricular (RV) risk scores used in adult patients to pediatric age group undergoing LVAD implantation., Methods: Twenty-two pediatric patients who underwent LVAD implantation were retrospectively reviewed from January 2014 to September 2018. Preoperative patient characteristics, hemodynamic parameters, and echocardiographic data were collected. Adult RV risk scores were calculated for all patients. Effects of all the parameters on RV function were also investigated. Study endpoints were RVF and in-hospital mortality., Results: Eleven (50%) of 22 patients were male. The mean age of the patients was 13.4 ± 3.8 years. The mean body surface area of the patients was 1.4 ± 0.4 m 2 . In five patients BiVAD implantation was performed. Of these five BiVAD patients two underwent successful heart transplant; two weaned from temporary RVAD and last patient died due to multi-organ failure. Four patients showed signs of early RVF; one patient was transplanted successfully while on medical support. Three patients developing RVF did not respond medical therapy necessitating ECMO and died in the early postoperative period. All risk scores and potential predictive factors were evaluated individually and in combination of several parameters. No significant predictor for RVF in pediatric patients that underwent LVAD implantation was found ( p  > 0.05)., Conclusion: Neither an adult risk score nor a predictive factor was successful in predicting RVF, alone or in combination due to limited number of patients and events. Large further investigations are needed to identify the predictors or scoring system in pediatric population.

Artificial muscles enable the design of soft implantable devices which are poised to transform the way we mechanically support the heart today. Heart failure is a prevalent and deadly disease, which is treated with the implantation of rotary blood pumps as the only alternative to heart transplantation. The clinically used mechanical devices are associated with severe adverse events, which are reflected here in a comprehensive list of critical requirements for soft active devices of the future: low power, no blood contact, pulsatile support, physiological responsiveness, high cycle life, and less-invasive implantation. In this review, prior art in artificial muscles for their applicability in the short and long term is investigated and critically evaluated. The main challenges regarding the effectiveness, controllability, and implantability of recently proposed actuators are highlighted and the future perspectives for attachment, physiological responsiveness, durability, and biodegradability as well as equitable design considerations are explored., (© 2023 The Authors. Advanced Materials published by Wiley-VCH GmbH.)

Patients with end-stage heart failure have poor quality of life and prognosis.Therapeutic options are scarce and not available for all:only few patients can be transplanted and several medical and surgical strategies have shown limited ability to influence prognosis and quality of life. In the past years, technological progress has realized devices capable of providing appropriate hemodynamic stabilization and recovery of secondary organ failure.In the recent years,these devices are assessed and discussed as definitive treatment for patients who do not qualify for transplantation or/and instead to transplantation (destination therapy).This indication is increasingly considered following the results of newest clinical study reporting long-term survival without device correlated adverse events using last generation devices, and acceptable quality of life.The current knowledge about Destination Therapy and some original data from the DAVID Study (an Italian multicenter prospective study designed to evaluate the patient’s survival rate and quality of life of patients implanted with these new devices as long-term support or destination therapy) are summarized.

Despite the clinical success and growth in the utilization of continuous flow ventricular assist devices (cfVADs) for the treatment of advanced heart failure, hemolysis and thrombosis remain major limitations. Inadequate and/or ineffective anticoagulation regimens, combined with high pump speed and non-physiological flow patterns, can result in hemolysis which often is accompanied by pump thrombosis. An unexpected increase in cfVADs thrombosis was reported by multiple major VAD implanting centers in 2014, highlighting the association of hemolysis and a rise in lactate dehydrogenase (LDH) presaging thrombotic events. It is well established that thrombotic complications arise from the abnormal shear stresses generated by cfVADs. What remains unknown is the link between cfVAD-associated hemolysis and pump thrombosis. Can hemolysis of red blood cells (RBCs) contribute to platelet aggregation, thereby, facilitating prothrombotic complications in cfVADs? Herein, we examine the effect of RBC-hemolysate and selected major constituents, i.e., lactate dehydrogenase (LDH) and plasma free hemoglobin (pHb) on platelet aggregation, utilizing electrical resistance aggregometry. Our hypothesis is that elements of RBCs, released as a result of shear-mediated hemolysis, will contribute to platelet aggregation. We show that RBC hemolysate and pHb, but not LDH, are direct contributors to platelet aggregation, posing an additional risk mechanism for cfVAD thrombosis. [ABSTRACT FROM AUTHOR]

Background Allosensitization has been shown to negatively affect post-heart transplant (HTx) survival even with a negative crossmatch. Whether allosensitization related to mechanical circulatory support (MCS) is associated with worse post-HTx survival remains controversial. Methods Adult HTx recipients listed in the United Network for Organ Sharing database (July 2006–December 2012) were identified. Multivariate Cox regression assessed the effect of allosensitization on survival. Propensity matching was performed to compare patients who were and were not allosensitized. Kaplan-Meier survival analysis compared matched and unmatched patients in the MCS and medically managed cohorts. Results We identified 11,840 HTx recipients, of whom 4,167 had MCS. MCS was associated with allosensitization in multivariate logistic regression. Each different MCS device was associated with worse post-HTx survival in multivariate Cox regression. Allosensitization did not predict post-HTx mortality in MCS patients (hazard ratio, 1.07; 95% confidence interval, 0.89–1.28; p = 0.48. Among patients without MCS, allosensitization was associated with post-HTx mortality (hazard ratio, 1.19; 95% confidence interval, 1.03–1.39; p = 0.02). Kaplan-Meier analysis revealed equivalent survival in unmatched and matched cohorts when MCS patients who were allosensitized were compared with non-allosensitized MCS patients. Among non-MCS patients, allosensitization was associated with worse survival in unmatched and matched analysis. Conclusions MCS was associated with allosensitization. For MCS patients, allosensitization did not independently predict worse post-HTx outcome. Among non-MCS patients, allosensitization was associated with worse post-HTx survival. Allosensitization appears to be a heterogeneous process influenced by presence of MCS. [ABSTRACT FROM AUTHOR]

Background Use of mechanical circulatory support in children has increased as more options have become available. A national account of the use of mechanical support in children and adolescents is essential to understanding outcomes, refining patient selection and improving quality of care. Methods The Pediatric Interagency Registry for Mechanical Circulatory Support (PediMACS) is a National Heart, Lung, and Blood Institute-supported nationwide registry for temporary and durable ventricular assist device (VAD) use in patients <19 years of age. Between the launch in September 2012 and June 2015, 37 hospitals in the USA have enrolled patients. This first report of data from PediMACS analyzed pre-implant patient characteristics, survival using competing outcomes, and adverse events. Results Two hundred pediatric patients underwent 222 durable VAD implants. Patients’ characteristics and outcomes of children supported with a temporary device ( n = 41) were not analyzed in this report. The etiology of heart disease included 146 (73%) patients with cardiomyopathy and 35 (18%) with congenital heart disease. Thirty patients (15%) transitioned from extracorporeal membrane oxygenation (ECMO) and 76 (38%) had previous cardiac surgery. Most patients were Interagency Registry for Mechanically Assisted Circulatory Support (INTERMACS) Level 1 (27%) or Level 2 (56%) at implant, with 13% at Level 3. Of the 200 patients supported with a durable device, 91 (46%) were supported with a pulsatile-flow device and 109 (55%) with a continuous-flow (CF) device. Patient age at first implant included 30 patients (15%) <1 year of age, 37 (19%) 1 to 5 years, 32 (16%) 6 to 10 years and 101 (51%) 10 to 18 years. Patients were supported with left ventricular assist device alone in 161 (81%), biventricular ventricular assist device in 29 (15%), right ventricular assist device in 4 (2.0%) and total artificial heart in 6 (3%), together comprising 783 months of follow-up. The 200 patients receiving primary durable devices had an actuarial survival of 81% at 6 months. Competing risk analysis at 6 months revealed that 58% of patients had been transplanted, 28% were alive on support, 14% had died and 0.6% recovered. In the overall cohort, there were 28 deaths. Reported serious adverse events included infection ( n = 78), bleeding ( n = 68), device malfu n ction ( n = 79) and neurologic dysfunction ( n = 52). Conclusions PediMACS constitutes the largest single data repository with detailed information of pediatric patients implanted with VADs. The first PediMACS report reveals favorable outcomes despite the varying patient characteristics and pump types. However, the rate of adverse events remains high. With further data collection, analysis of patient risk factors critical to improving outcomes will be possible. [ABSTRACT FROM AUTHOR]

Background Continuous-flow (CF) ventricular assist devices (VADs) have largely replaced pulsatile-flow VADs in adult patients. However, there are few data on CF VADs among pediatric patients. In this study we aimed to describe the overall use, patients’ characteristics and outcomes of CF VADs in this population. Methods The Pediatric Interagency Registry for Mechanical Circulatory Support (PediMACS) is a national registry for U.S. Food and Drug Adminstration (FDA)-approved VADs in patients <19 years of age. Patients undergoing placement of durable CF VADs between September 2012 and June 2015 were included and outcomes were compared with those of adults from the Interagency Registry for Mechanically Assisted Circulatory Support (INTERMACS). Results CF VADs were implanted in 109 patients at 35 hospitals. The median age at implantation was 15 years (2.8 to 18.9 years) and median weight was 62 kg (range 16 to 141 kg). The underlying disease was cardiomyopathy in 89 (82%) patients. The INTERMACS level at time of implant was Level 1 in 20 (19%), Level 2 in 64 (61%) and Levels 3 to 7 in 21 (20%) patients. Most were implanted as LVADs ( n = 102, 94%). Median duration of support was 2.3 months (range <1 day to 28 months). Serious adverse event rates were low, including neurologic dysfunction (early event rate 4.1 per 100 patient-months with 2 late events). Competing outcomes analysis at 6 months post-implant indicated 61% transplanted, 31% alive with device in place and 8% death before transplant. These outcomes compared favorably with the 3,894 adults supported with CF VADs as a bridge to transplant. Conclusions CF VADs are commonly utilized in older children and adolescents, with excellent survival rates. Further study is needed to understand impact of patient and device characteristics on outcomes in pediatric patients. [ABSTRACT FROM AUTHOR]

The low preload and high afterload sensitivities of rotary ventricular assist devices (VADs) may cause ventricular suction events or venous congestion. This is particularly problematic with rotary biventricular support (BiVAD), where the Starling response is diminished in both ventricles. Therefore, VADs may benefit from physiological control systems to prevent adverse events. This study compares active, passive and combined physiological controllers for rotary BiVAD support with constant speed mode. Systemic (SVR) and pulmonary (PVR) vascular resistance changes and exercise were simulated in a mock circulation loop to evaluate the capacity of each controller to prevent suction and congestion and increase exercise capacity. All controllers prevented suction and congestion at high levels of PVR (900 dynes s cm) and SVR (3000 dynes s cm), however these events occurred in constant speed mode. The controllers increased preload sensitivity (0.198-0.34 L min mmHg) and reduced afterload sensitivity (0.0001-0.008 L min mmHg) of the VADs when compared to constant speed mode (0.091 and 0.072 L min mmHg respectively). The active controller increased pump speeds (400-800 rpm) and pump flow by 2.8 L min during exercise, thus increasing exercise capacity. By reducing suction and congestion and by increasing exercise capacity, the control systems presented in this study may help increase quality of life of VAD patients. [ABSTRACT FROM AUTHOR]