Assist Device Research Articles

Outcomes of implantable cardioverter-defibrillators in patients with a left ventricular assist device: a systematic review and meta-analysis

Abstract Introduction Implantable Cardioverter-Defibrillators (ICDs) improve survival in advanced heart failure with reduced ejection fraction (HFrEF) and prevent sudden cardiac death. However, the prognostic benefits of ICDs among patients with a Left Ventricular Assist Device (LVAD) remain uncertain and controversial. Therefore, we conducted a systematic review and meta-analysis to assess the effectiveness and safety of ICD implantation among LVAD recipients. Methods We performed a systematic review and meta-analysis following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. We searched PubMed and EMBASE for the peer-reviewed articles published in English assessing the impact of ICD implantation among LVAD recipients, till 10/01/2024. ICD implantation was defined as implantation before LVAD, simultaneous implantation with LVAD, or within 30 days of LVAD insertion. Two independent review authors assessed the quality and risk of bias of the included studies. A random-effect model was used to combine data in forest plots. The primary outcome was all-cause mortality associated with ICD implantation compared to no ICD implantation, and the secondary outcomes included ventricular arrhythmia (VT), and hemorrhagic stroke. Heterogeneity was assessed using Q test and I2, with I2 > 50% indicating marked heterogeneity. Results A total of 13 observational studies comprising 54571 recipients of LVAD were included in the analysis of the primary outcome. All-cause mortality was similar among patients with ICD versus no ICD (Odds Ratio [OR]= 0.77; 95% CI, 0.57-1.04, I2= 89%, P=0.09), as shown in Figure 1. Likewise, ICD implantation was associated with similar rates of VT and hemorrhagic stroke (VT: OR= 1.81, 95% Cl, 0.82-4.01, I2= 90%, P=0.14; hemorrhagic stroke: OR= 1.01, 95% Cl, 0.81-1.25, I2= 0%, P= 0.95). Conclusion Among patients with HFrEF and LVAD as advanced heart failure therapy, ICD implantation didn’t provide additional prognostic survival benefit, suggesting possible use of LVAD without ICD implantation.Figure 1.Forest plot of mortality

Influence of timing of impella insertion on the prognosis of acute myocardial infarction complicated with cardiogenic shock requiring ECPELLA

Abstract Background/Introduction In patients with cardiogenic shock (CS), a combination of Impella-a percutaneous ventricular assist device with a catheter-type micro-axial heart pump-and venoarterial extracorporeal membrane oxygenation (ECPELLA) has been reported to have a better prognosis compared to venoarterial extracorporeal membrane oxygenation (VA-ECMO) alone, although it was associated with more complications. In contemporary clinical practice, ECPELLA has often been used in place of VA-ECMO alone. However, in many cases of acute myocardial infarction (AMI) with CS, there is controversy regarding the prioritization of Impella or VA-ECMO installation. Purpose The current study aims to clarify the factors of Impella use before VA-ECMO, the impact of the timing of Impella insertion (before or after VA-ECMO) for 30-day mortality, and major adverse events (MAEs) in the two groups. Methods The Japanese registry for Percutaneous Ventricular Assist Device (J-PVAD) Registry is a nationwide registry enrolling 5,718 consecutive Japanese patients treated with Impella between February 2020 and December 2022. The current study population consisted of 1,082 patients with AMI complicated by CS excluding cardiopulmonary arrest on arrival or using only Impella, who were divided into 2 groups; Impella use before and after VA-ECMO. Results Among the current study population, 323 patients (30%) used Impella before VA-ECMO, and 759 patients (70%) used Impella after VA-ECMO. Patients who used Impella before VA-ECMO were older (72 vs. 68 years old, P<0.0001) and had higher left ventricular ejection fraction (LVEF) (30 vs 20 %, P<0.0001), lower lactate level (5.6 vs 9.1 mmol/L, P<0.0001), and more often ST-elevation myocardial infarction (MI) (82% vs 76%, P<0.0001), whereas those patients had less often out-of-hospital cardiac arrest (OHCA) (13% vs 45%, P<0.0001), in-hospital cardiac arrest (IHCA) (27% vs 63%, P<0.0001), and prior heart failure (9.5% vs 16%, P=0.006). The factors of Impella use before VA-ECMO were 75 years or older, dyslipidemia, the absence of OHCA, the absence of IHCA, the absence of prior MI, and the absence of LVEF less than 30%. The cumulative 30-day incidence of all-cause death was 46.2% in patients with Impella use before VA-ECMO and 53.4% in those with Impella use after VA-ECMO (Log-rank P=0.02). After adjusting confounders, there was no excess risk of Impella use before VA-ECMO relative to Impella use after VA-ECMO (adjusted HR, 0.87; 95%CI, 0.55-1.37; P=0.55). Regarding major adverse events, hemolysis was significantly more frequent in patients with Impella use before VA-ECMO, while stroke was significantly more common in patients with Impella use after VA-ECMO. Conclusions The prognosis with AMI complicated by CS requiring ECPELLA remained poor. The 30-day mortality was lower in patients with Impella use before VA-ECMO compared to after VA-ECMO. However, after adjusting for confounders, there was no difference between the two groups.

A meta-analysis of the efficacy and safety of exercise-based cardiac rehabilitation in patients with left ventricular assist devices

Abstract Background Left Ventricular Assist Devices (LVADs) and heart transplantation stand out as the two well-established and effective therapeutic approaches for managing patients with advanced heart failure. Exercise-based cardiac rehabilitation (EBCR) has been demonstrated to improve functional capacity in patients with LVAD. Purpose We aim to assess the efficacy and safety of EBCR in patients with LVAD. Also, to compare high-intensity (HIT) versus moderate-intensity (MIT) EBCR regimens in patients with LVAD. Methods A systematic review and meta-analysis synthesizing evidence from randomized controlled trials (RCTs) studies obtained from PubMed, Embase Cochrane, Scopus, and WOS until January 2024. We used the fixed-effects model to report dichotomous outcomes using risk ratio (RR) and continuous outcomes using standardized mean difference (SMD) with a 95% confidence interval (CI). Results Six RCTs with 160 patients were included. There was no significant difference between EBCR and standard care regarding peak VO2 change [SMD: 0.24 with 95% CI (-0.14, 0.62), P= 0.21] and six-minute walk distance (6-MWD) change [SMD: 0.28 with 95% CI (-0.11, 0.66), P= 0.16]. Also, there was no significant difference between HIT and MIT exercise regarding peak VO2 change [SMD: 0.20 with 95% CI (-0.41, 0.82), P= 0.52] and 6-MWD change [SMD: 0.07 with 95% CI (-0.54, 0.69), P= 0.81]. Moreover, EBCR was associated with a significant decrease in the incidence of any adverse events when compared to usual care with [RR: 0.80 with 95% CI (0.65, 0.99), P= 0.04], while there was no significant difference between HIT and MIT exercise regarding the incidence of any adverse events [RR: 0.38 with 95% CI (0.02, 9.22), P= 0.55]. Conclusion EBCR did not improve functional capacity in patients with LVAD, with no significant effect on peak VO2 or 6-MWD.

Acute myocarditis presentation and intra-hospital prognosis: results of the multicenter prospective MYOCARDITIRM study

Abstract Background Acute myocarditis (AM) usually presents as chest pain with rising troponin and normal coronary arteries. Despite frequent favorable evolution at the acute phase, it is associated with heart failure and ventricular rhythm disorders and is considered the leading cause of sudden cardiac death in young apparently healthy adults. There is no recommendation for AM, only expert consensus, given the lack of important databases for a strong level of confidence. Methods We performed a multicenter prospective observational study of patients admitted for AM acknowledged by cardiac MRI to describe baseline characteristics, management, in-hospital and long-term outcomes of AM patients in France. Secondary objectives were to investigate determinants of prognosis, modalities of treatment and follow-up, and to identify gaps between expert consensus and real-life management. Results We enrolled 805 consecutive patients hospitalized for AM in 49 participating centers between May 2016 and February 2019. Median age was 31 (IQR 23-41) with 19% of female. Chest pain was the most frequent symptom (93%) and 112 (14%) had severity criteria upon admission (LVEF<50% or severe ventricular arrythmia or high-grade AV block or cardiogenic shock). ST elevation was observed in 49% of patients. One 26-years old patient died during initial hospital stay. Overall, 62 patients (8%) experienced intra-hospital complication of their AM, defined as a combined endpoint of death, LVEF<40% (MRI), sustained ventricular or supraventricular arrythmia, acute renal failure, cardiogenic shock, need for ventricular assistance device, need for inotropic drugs, temporary cardiac pacing, pace-maker or cardiac defibrillator implantation. Patients with initial severity criteria were 10 times more likely to present intra-hospital complication (33% vs 3.6%, p<0.001). Conclusion This prospective cohort represents the largest database on AM worldwide. Here we report baseline characteristics and in hospital events. Most patients had typical presentation with favorable outcomes but as much as 8% of patients did exhibit intra-hospital complication. The prospective follow up will provide valuable data to better identify subset of patients with poor prognosis that may be of interest to develop new therapeutic strategies.Acute myocarditis on cardiac MRI

CMR predictors of acute right heart failure after LVAD implantation

Abstract Background Acute right heart failure (RHF) is one of the most dangerous complications after placement of left ventricular assisted device (LVAD), having a significant impact on prognosis, and is estimated to be around 3 to 35%. Even though right ventricular evaluation with hemodynamical and echocardiographic measurements is a key aspect prior to LVAD implantation, prediction of RHF remains a challenge in daily clinical practice. Purpose To identify cardiac magnetic resonance (CMR) predictors of RHF after LVAD placement. Methods We retrospectively enrolled patients referred to our centre for implantation who also underwent CMR scan prior to LVAD implantation. Acute RHF was defined according to Mechanical Circulatory Support Academy Research Consortium (MRC ARC) criteria. Baseline characteristics, preoperative laboratory, echocardiographic, right heart catheterization (RHC) and CMR parameters were obtained. Patients were divided into two groups based on the development of acute RHF. The variables showing significant differences between the two groups were analysed with the receiver operating characteristic (ROC) curves to find the best cut-offs and then combined into a risk score. Results We enrolled 54 patients who underwent continuous-centrifugal flow LVAD implantation from 2013 to 2021 in whom a CMR within median time of 30 days pre-implantation was available. Four patients were excluded due to low quality images. Among the final cohort of 50 patients, 15 (28%) developed acute RHF. Patients who developed RHF showed worse INTERMACS class, worse renal and liver function, higher central venous pressure at RHC, worse TAPSE at echocardiography and overall smaller left ventricles at the CMR analysis when compared to those who had not acute RHF. No CMR derived right ventricle parameters nor moderate to severe tricuspid regurgitation at echocardiography were different among the two groups. We found that CMR-derived LV mass indexed < 65 g/m2, left ventricular end diastolic diameter (LVEDD) < 70 mm, and LV eccentricity index >1,12 were independent predictors of acute RHF. A CMR-derived score with these three parameters was built (1 point for each). This CMR score has shown to be an independent predictor of acute RHF at multivariate analysis with an odds ratio of 7,084 (CI 95%1.614-37.734) when corrected for other clinical and instrumental predictors of acute RHF. Conclusions Our study proposes a simple scoring system based on three CMR- derived parameters (LVEDD, LV mass indexed and LV eccentricity index) to screen for acute RHF prior LVAD implantation. This score shows promise to be an independent predictor of acute RHF, even when adjusted for clinical, echocardiographic, and haemodynamic parameters. Our model is built on CMR measurement of the LV, showing how patients with smaller ventricles and a left displacement of the interventricular septum (expressed with a higher LV eccentricity index) are at higher risk of developing acute RHF.ROC curves

Impact of mitral transcatheter edge-to-edge repair in patients with advanced heart failure evaluated for heart transplantation

Abstract Background Heart transplantation is sometimes the only therapeutic option in patients with advanced heart failure (HF), impaired ventricular function and significant functional or secondary mitral regurgitation (MR). The shortage of organs and the limitations of the recipient make it necessary to consider other therapeutic alternatives in these patients, such as mitral transcatheter edge-to-edge repair (M-TEER). The MitraBridge registry has recently been published in which they analyze the potential effect of M-TEER in patients with advanced HF and moderate-severe MI who are candidates for heart transplantation (mean age 59 years, left ventricular ejection fraction (LVEF) 27%); after a mean follow-up of 24 months, complete in 82.4%, they report an overall survival of 78.5%, a combined event-free survival of 47%, with a 6.5 % need for urgent transplantation and an HF hospitalization rate after M-TEER of 44/100 patient-years. The aim of our study is to assess the impact of M-TEER on mortality and the combined events of death, HF rehospitalization and the need for urgent transplantation or a ventricular assistance device in patients with moderate-severe functional MI and advanced HF who have also been evaluated for cardiac transplantation in our hospital. Methods This is a retrospective analysis of a prospective registry. Of the patients treated by M-TEER for severe MI, we selected those with advanced HF (defined as LVEF≤35%, and/or advanced functional class (NYHA III-IV)) who had also been evaluated as possible candidates for inclusion in the heart transplant list. Results From November 2011 to December 2023, 191 patients were treated by M-TEER, of whom 38 patients met the established criteria (median age 59 years [48-65], 31 (81%) males, mean LVEF was 26 ± 6%). All patients had at least one previous hospitalization for HF and optimal medical treatment according to guidelines; the rest of the baseline clinical characteristics are listed in Table 1. During the follow-up after M-TEER, with a median of 34 months [7-70], the probability of overall survival at 2 years was 75.6%. The combined endpoint of death, need for urgent transplantation or a ventricular assist device, and rehospitalization for heart failure occurred in 26 patients with a 2-year event-free survival probability of 48% (Figure 1). Five patients (13%) were transplanted, one (2.6%) urgently. Prior to M-TEER therapy, the rate of HF hospitalization was 108 hospitalizations/100 patient-years, which was significantly reduced after the procedure to 33 hospitalizations/100 patient-years (rate ratio 0.31 [95% CI 0.21-0.45, p<0.0005]). Conclusions In patients with advanced HF and severe functional MR who are candidates for cardiac transplantation, M-TEER is an effective therapeutic alternative, achieving a survival rate of more than three-quarters of the patients at 2 years of follow-up, a significant reduction in HF hospitalizations, and a low rate of need for cardiac transplantation.

Afterload mismatch is associated with gender mismatch and negatively affect long-term outcome after heart transplant

Abstract Background Cardiac physiology changes after heart transplant (HT), resulting in a restrictive physiology with an increase in both arterial elastance (Ea) and ventricular elastance (Ees). This leads to a higher susceptibility to develop afterload mismatch, although the early identification of this phenomenon has not yet been explored. The aim of this study is to identify the presence of afterload mismatch after HT, its determinants, and its impact on cardiac mortality. Methods We conducted an observational, single-centre study based on the historical cohort of patients who underwent HT from 1985 to 2015 at our institution. We included patients who had survived the first year after HT with left ventricular ejection fraction (LVEF) ≥ 50%, International Society of Heart and Lung Transplantation (ISHLT) cardiac allograft vasculopathy of grade 0-1, and ISHLT acute cellular rejection of grade 0-1R at 1 year after HT. Ea and Ees were calculated using a non-invasive method based on blood pressure and end-systolic volume and end-diastolic volume measured at transthoracic echocardiography. Patients were grouped in 3 categories according to the presence of increased afterload and afterload mismatch as follows: low afterload (LA - Ea lower the median), matched high afterload (MHA - Ea higher of equal than the median, Ees higher or equal than the median), afterload mismatch (AM - Ea higher or equal than the median, Ees lower than the median). The impact of AM on long-term outcome, defined as cardiac mortality, was investigated, as well as predictors of AM. Results The study cohort consisted of 345 HT patients. The median of Ea and Ees were 4.0mmHg/mL and 6.75mmHg/mL, respectively. 49 patients (13%) developed AM, while LA and MHA groups accounted for 49% and 36% of the cohort, respectively. Patients with AM were mostly male (91%), with ischemic heart disease (45%) and a higher percentage of left ventricular assisted device prior to HT (8%). LVEF was lower in AM (57% vs 63% and 64% for LA and MHA respectively, p < 0.0001), while stroke volume was lower than LA and similar to MHA (27ml vs 35mL and 26mL for LA and MHA respectively, p = 0.0001). Predictors of AM were male recipient from male donor (Mr/Md) (β 015, p = 0.0067) and Mr from female donor (Mr/Fd) (β 0.6, p = 0.0078). After a median of 11.3-year follow-up, 59 (17%) HT recipients died. Cardiac mortality was higher in AM than in the other groups (AM median survival 17.2y vs 27.8y and 24.1y for LA and MHA respectively, log-rank p = 0.005). After adjusting for confounding variables, AM was a predictor of cardiac mortality (HR: 2.26; 95%CI 1.18 – 4.35), such as Mr/Fd (HR 2.94; 95%CI 1.18 – 4.35, p = 0.0358). Conclusion AM, in the context of a normal LVEF, is associated with male donor and sex mismatch, and negatively affects long-term outcome after HT.KM curvesCox proportional hazard model

Third ventilatory threshold in heart failure patients undergoing CPET: a prognostic analysis

Abstract Introduction One crucial element in cardiopulmonary exercise testing (CPET) involves identifying the first and second ventilatory thresholds (VT), VT1 and VT2, which hold known prognostic implications. If the individual can sustain exercise considerably beyond VT2, a third breakpoint (VT3 – Figure A) may emerge, coinciding with heightened hyperventilation to counter metabolic acidosis. Historically, this point has been mainly described among athletes and its meaning is still not entirely clear. We aimed to assess the prognostic value of VT3 in patients with heart failure (HF). Methods Retrospective, single-center study enrolling HF patients undergoing CPET from 2015 to 2021. We evaluated the typical CPET parameters along with the three ventilatory thresholds: VT1, VT2, and the newly introduced VT3. The primary outcome was a composite of cardiovascular death, urgent heart transplant, need for left ventricle assistance device and HF hospitalizations. Results We included 221 patients (82% men, mean age 58±12 years), among whom 69% had ischemic heart failure aetiology. The mean left ventricular ejection fraction (LVEF) was 34±9%, with a mean respiratory exchange ratio 1.15±0.082, mean pVO2 18.5±6.3, and a mean VE/VCO2 slope of 41.3±12.9. VT3 was attained by 43% (n = 94) of the patients. In comparison to those who did not achieve VT3, patients who reached this threshold were younger (56±11 vs 60±12; p = 0.05), had a higher pVO2 (20.5±6.9 vs 17±5.4; p = 0.05), higher RER (1.16±0.86 vs 1.13±0.78; p = 0.05), and lower VE/VCO2 slope (39±10.3 vs 43±14.3; p = 0.05). Regarding the three ventilatory thresholds (VT1, VT2, VT3), 7% (n=17) achieved a maximum of one threshold, 50% (n=110) achieved two thresholds, and 43% (n=94) reached all three thresholds. After a median follow-up of 2,3 years patients with identifiable VT3 had significantly better prognosis (HR 0,434; 95%CI 0,246-0,767; p=0,004) than those without this threshold. Furthermore, the number of identifiable ventilatory thresholds correlated positively with prognosis. In fact, patients with only 2 thresholds have twice the probability of developing an event and those with one or zero identifiable thresholds have a 4-fold increase in the probability of events (Figure C). Conclusion In a cohort of patients with HF, those with identifiable VT3 had a lower incidence of events. This parameter may aid in prognostic stratification in this population. However, this findings warrant further prospective validation.Figure 1

Dynamic modeling of variable speed left ventricular assist devices coupled to the cardiovascular system.

Most of the modeling of the Left Ventricular Assist Devices (LVADs) coupled with the cardiovascular system is based on the assumption of constant rotational speed. Compared with the traditional inertial model, the validated hysteresis model can take into account the unsteady characteristics of LVADs, but it fails to work under the condition of variable speed modulation. This study takes into consideration the impact of speed variations on the unsteady hysteresis effects. The time constant in the hysteresis model is treated as a time-varying parameter, thereby developing a new model applicable to variable speed modulation. Under sinusoidal speed modulation at various phases, a comparative analysis was undertaken among the steady-state model, inertial model, and the new model. Transient Computational Fluid Dynamics (CFD) simulations and existing experimental results are used for validation. The new model provides a more accurate method for the predicting the characteristics of LVAD in the coupled model under varying pump speeds, and exhibits higher linearity in the work done by the left ventricle and the blood pump, and , which is aligning closely with the experimental results. This enhancement renders it applicable for proactive control predictions and passive control validations.

Pooled comparative analysis of transcatheter aortic valve replacement versus surgical aortic valve replacement in patients with left ventricular assist device.

A thorough literature search was conducted on patients with Left Ventricular Assist Device (LVAD) and aortic insufficiency undergoing transcatheter aortic valve replacement (TAVR). We identified all original research studies that compared the long-term outcomes of surgical transcatheter aortic valve replacement (SAVR) versus TAVR for patients with LVAD, published between 1990 and 2023. The primary endpoint was the composite of in-hospital mortality, stroke, transient ischemic attack, myocardial infarction (MI), pacemaker implantation, vascular complications and cardiac tamponade. Secondary endpoints were the median overall survival (OS), the incidence of acute kidney injury (AKI), any bleeding needing transfusions or reintervention and cost. A total of fourteen studies and 358 patients were included (TAVR: 242; SAVR: 116). The composite outcome, the incidence of AKI, the bleeding needing transfusion, along with cost were significantly higher in the SAVR group. In addition, there was no significant difference between TAVR and SAVR in terms of median OS. The median OS in the TAVR group was 18 months. Finally, the most common causes of death were progression of heart failure and pneumonia. The present meta-analysis indicates that TAVR is associated with enhanced outcomes compared to SAVR for patients with LVAD presenting aortic insufficiency. Further well-designed original studies with greater sample sizes are necessary to validate our findings.

Impact of Preoperative Right Ventricular Function on Acute Renal Failure Development in Patients With Ventricular Assist Devices

Impact of Preoperative Right Ventricular Function on Acute Renal Failure Development in Patients With Ventricular Assist Devices

Examining Long-Term Influences of Frailty on Outcomes for Adults Undergoing Left Ventricular Assist Device Therapy.

Frailty is common in adults with end-stage heart failure receiving a left ventricular assist device (LVAD). Short-term studies show frailty reversal post-LVAD. Little is known about long-term frailty and how frailty relates to key LVAD outcomes, including depression, quality of life (QoL), and cognition beyond 6 months. The purpose of this study was to examine physical frailty, depression, QoL, and cognition from pre-LVAD implantation to 3, 6, and 12 months post-LVAD implantation. Clinical data and measures of physical frailty, depression, QoL, and cognition pre- and post-LVAD were extracted from an existing institutional database. Descriptive statistics and tests for statistical significance were used to describe and compare changes over time. Frailty trajectories were identified to describe physical frailty from pre-LVAD to 12 months post-LVAD. The sample (n = 46) was predominantly male (76%), with a mean age of 64.7 ± 11 years, and over half (n = 25) were physically frail. Physical frailty was reduced by nearly half at 12 months. Frailty, depression, and QoL significantly improved at all time points (P < .001). Improvements in cognition did not reach statistical significance. Recipients of LVAD without improvement in frailty exhibited worse depression, QoL, and cognition scores at 12 months compared with those not frail pre-LVAD or no longer frail post-LVAD implantation. Some recipients of LVADs experienced physical frailty reversal with benefits sustained long-term. Those without improvement recorded worse long-term patient-reported outcomes. Identifying factors that predict physical frailty response to LVAD implantation is a key area of future research.

Video Game-Based Trunk Exercises for Rehabilitation in Chronic Stroke Survivors: A Mixed-Methods Feasibility Study.

Aim: To assess the feasibility of video game-based trunk exercises using the Valedo® system in a chronic stroke population. Method: Ten chronic stroke survivors (eight males and two females, mean age 63 ± 15 years) were asked to complete 18 intervention sessions, each lasting 45 min., over 6-8 weeks. Feasibility was evaluated quantitatively using the Psychosocial Impact of Assistive Devices Scale (PIADS) as well as through recruitment, retention, adherence, and safety measures. Qualitative data on feasibility were collected through post-intervention semi-structured interviews. Descriptive analysis was used to summarize participant characteristics, recruitment, retention, and adherence. Qualitative data were analyzed using thematic analysis of the interviews. Results: Twelve stroke survivors were recruited from Southampton (United Kingdom) and Riyadh (Kingdom of Saudi Arabia), with two participants dropping out after the baseline assessment session. The remaining ten participants completed the study with a mean adherence of 96.11% to the planned sessions. No serious adverse effects were reported, however, four participants did experience trunk muscle tightness and fatigue. Post-intervention interviews revealed that participants encountered some physical and cognitive challenges while playing the Valedo video games. However, they felt that the implementation of trunk exercises using video games was safe, as the exercises were performed in a secure environment and in safe positions. Conclusions: The findings suggest that the Valedo system is feasible for delivering trunk exercises to chronic stroke survivors. Several factors should be considered when implementing this type of intervention in the future.

A reproducible extended ex-vivo normothermic machine liver perfusion protocol utilising improved nutrition and targeted vascular flows

BackgroundNormothermic machine perfusion of donor livers has become standard practice in the field of transplantation, allowing the assessment of organs and safe extension of preservation times. Alongside its clinical uses, there has been expanding interest in extended normothermic machine perfusion (eNMP) of livers as a potential vehicle for medical research. Reproducible extended normothermic machine perfusion has remained elusive due to its increased complexity and monitoring requirements. We set out to develop a reproducible protocol for the extended normothermic machine perfusion of whole human livers.MethodsHuman livers declined for transplantation were perfused using a blood-based perfusate at 36 °C using the Liver Assist device (XVIVO, Sweden), with continuous veno-venous haemofiltration in-parallel. We developed the protocol in a stepwise fashion.ResultsPerfusion techniques utilised included: targeted physiological vascular flows, phosphate replacement (to prevent hypophosphataemia), N-acetylcysteine (to prevent methaemoglobin accumulation), and the utilisation of sodium lactate as both a nutritional source and real-time measure of hepatocyte function. All five human livers perfused with the developed protocol showed preserved function with a median perfusion time of 168 h (range 120–184 h), with preserved viability throughout.ConclusionsLivers can be reproducibly perfused in excess of 120 (range 121–184) hours with evidence of preserved hepatocyte and cholangiocyte function.

HeartMate III Autonomy Assistant in a Hemiplegic Left Ventricular Assist Device Patient: A Case Report.

Terminal heart failure presents challenges, requiring cardiac transplantation, or mechanical circulatory support. Limited donor organ availability has made mechanical support crucial. Advances in centrifugal-flow systems, compared to axial-flow, have improved patient outcomes by reducing adverse events. Rehabilitation is vital for patient independence postimplantation. We developed a tool to aid hemiplegic patients in managing power sources. A 44 year old male with tritroncular ischemic heart disease and a 15% ejection fraction. He underwent a double bypass and left ventricular assist device (LVAD) implantation while awaiting a transplant. Postsurgery, the patient suffered a stroke, leading to left motor impairments. To assist in managing LVAD power sources, an autonomous tool with a Woodcast support base and antislip surface was developed. The tool improves autonomy and quality of life for motor-impaired patients. It is designed to be portable, adaptable, supporting various mobility levels. Real-world evidence shows it reduces time and alarms for battery changes, proving effective in home settings. The tool significantly enhances hemiparetic patients' self-care and independence, showing promise for motor-impaired individuals. Further research is needed to evaluate long-term benefits and challenges.

Ventricular Assist Device Infections: Epidemiology, Treatment, and Outcomes in Transplant

Ventricular Assist Device Infections: Epidemiology, Treatment, and Outcomes in Transplant

Performance evaluation of an automatically controlled transcutaneous energy transfer system powering left ventricular assist device.

The survival rate of LVAD recipients may be improved by eliminating the infection failure mode at the percutaneous lead entry site. Wireless powering through a Transcutaneous Energy Transfer System (TETS) is a promising solution for achieving this. However, automatic controls need to be employed to compensate for the variations in efficiency and power transfer due to changes in load and coil-to-coil gaps. This article discusses the results of invitro and animal models performance evaluation of an automatically controlled TETS for powering a Left Ventricular Assist Device. It was found that power up to 20 W could be transferred at an axial gap of 30 mm. A 5% variation in speed and a 2% change in flow rate are observed with the change in tissue thickness, in porcine carcass model. The LVAD could be operated at the required RPM irrespective of the change in axial positions.

Measurement and performance evaluation of triple band differential integrated extraoral rectifying antenna for data transfer and RF energy harvesting for tongue drive system

Wearable assistive devices are vitally important for tetraplegic individuals to provide valuable insights into their intended directives tailored to tongue motions in wireless healthcare industries. The flexible differentially driven extraoral antenna and rectenna measurement system are developed to enable differential sensing and monitoring of the set of unique tongue gestures for extraoral tongue drive system (eTDS) applications in three frequency bands of Industrial, Scientific, and Medical (ISM) (915.0 MHz, 2400 MHz, and 5800 MHz). The performance analysis is carried out using the heterogeneous human head model. The differential rectifier is coplanarly integrated with the differential extraoral antenna on the same 0.254 mm thin and 9.5 mm wider Rogers RT/ Duroid 6010 LM substrate. The footprint of the fabricated differential rectenna is 0.135 \\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$\\:{\\varvec{\\lambda\\:}}_{\\varvec{g}}\ imes\\:$$\\end{document} 0.082 \\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$\\:{\\varvec{\\lambda\\:}}_{\\varvec{g}}$$\\end{document}\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$\\:\ imes\\:$$\\end{document} 0.002 \\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$\\:{\\varvec{\\lambda\\:}}_{\\varvec{g}}$$\\end{document} where the planar size of differential rectifier is 15.75\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$\\:\\:\ imes\\:$$\\end{document} 2.5 mm2. The fabricated systems are situated closely to an artificial head model. The maximum conversion efficiency achieved at 2400 MHz and 5800 MHz is 83.45% and 74.8%, respectively, for 11 dBm of RF input power. Further, the link analysis, including interfacing circuit losses, was carried out theoretically at 915 MHz. Thus, the proposed differential extraoral systems can be employed to acquire and transmit the user intentions in eTDS inspired healthcare applications.

A Lightweight Blind Obstacle Detection Network for Mobile Side

Abstract. China has the longest and widest distribution of blind corridors in the world, but in many cities they are virtually non-existent, with all kinds of obstacles affecting the movement of the blind. Thus, guaranteeing safe traveling for the blind has become an increasingly important topic. Some existing assistive traveling devices for the blind have problems such as poor portability and low-cost performance. With the rise of the mobility era and the rapid development of deep learning technology, the target detection of blind obstacles on cell phones has become feasible. In this paper, we take the target detection model YOLOv8n as the base network, redesign the neck of the network, use GS convolution as the basis, adopt one-time aggregation and cross-channel branching to build a lightweight module, and use the CARAFE operator as the up-sampling method, and stack the lightweight module with CARAFE operator to build a new feature fusion layer, forming a lightweight feature-aware enhanced target detection network. The results show that the accuracy still reaches 99.5% of the original network under the premise that the model size is reduced by 1.2%, and the improved network achieves a balance between accuracy and lightweight.

HeartMate 3 Ventricular Assist Device in a Single-Ventricle and Single-Lung Patient Palliated With a Bidirectional Glenn.

We describe a 15 year old patient with failing second-stage single-ventricle palliation and left pulmonary artery thrombosis successfully supported with HeartMate 3 ventricular assist device and a Fontan completion as destination therapy.