To investigate the biomechanical effects of direct ventricular assistance and explore the optimal loading mode, this study established a left ventricular model of heart failure patients based on the finite element method. It proposed a loading mode that maintains peak pressure compression, and compared it with the traditional sinusoidal loading mode from both hemodynamic and biomechanical perspectives. The results showed that both modes significantly improved hemodynamic parameters, with ejection fraction increased from a baseline of 29.33% to 37.32% and 37.77%, respectively, while peak pressure, stroke volume, and stroke work parameters also increased. Additionally, both modes showed improvements in stress concentration and excessive fiber strain. Moreover, considering the phase error of the assist device\'s working cycle, the proposed assist mode in this study was less affected. Therefore, this research may provide theoretical support for the design and optimization of direct ventricular assist devices.
为了研究直接心室辅助的生物力学影响以及探究最优的加载模式，本文基于有限元方法建立了心衰患者的左心室模型，并提出了一种维持压迫力峰值的加载模式，从血流动力学和生物力学两个方面与传统的正弦加载模式进行了对比。结果表明，两种模式都能显著提升血流动力学参数，射血分数分别从基线29.33%增加到37.32%与37.77%，峰值压力、每搏量和每搏功等参数都有所增加；且两种模式的应力集中、过度纤维应变等现象均有所改善。然而，当考虑到辅助装置工作周期的相位误差时，本文所提出的辅助模式受到的影响更小，故本文研究或可为直接心室辅助装置的设计和优化提供理论支持。.

This study uses CFD methods to investigate the effects of the impeller\'s geometry on the hemodynamic characteristics, pump performance, and blood damage parameters, in a percutaneous microaxial Mechanical Circulatory Support (MCS) device. The numerical simulations employ the steady state Reynolds-Averaged Navier-Stokes approximation using the SST k-ω turbulent model. Three different impeller models are examined with different hub conversion angles (α = 0○, 3○ and 5○). The analysis includes 23 cases for different pressure heads (Δp = 60-80 mmHg) and angular velocities (ω = 30-52 kRPM). The obtained flow rate is compared between the cases to assess the effect of the impeller\'s design and working conditions on the pump performance. The comparative risk of shear-induced platelet activation is estimated using the statistical median of the stress-accumulation values calculated along streamlines. The risk of hemolysis is estimated using the average exposure time to shear stress above a threshold (τ > 425 Pa). The results reveal that the shape of the impeller\'s hub has a great impact on the flow patterns, performance, and risk of blood damage, as well as the angular velocity. The highest flow rate (Q = 3.7 L/min) and efficiency (η = 11.3 %) were achieved using a straight hub (α = 0○). Similarly, for the same condition of flow and pressure, the straight hub impeller has the lowest blood damage risk parameters. This study shed light on the effect of pump design on the performance and risk of blood damage, indicating the roles of the hub shape and angular velocity as dominant parameters.

Objectives. Temporary mechanical circulatory support (TMCS) has become a component in the therapeutic strategy for treatment of cardiogenic shock as a bridge-to-decision. TMCS can facilitate recovery of cardiopulmonary function, end-organ function, and potentially reduce the surgical risk of left ventricular assist device (LVAD) implantation. Despite the improvements of hemodynamics and end-organ function, post-LVAD operative morbidity might be increased in these high-risk patients. The aim of the study was to compare outcomes after Heartmate 3 (HM3) implantation in patients with and without TMCS prior to HM3 implant. Methods. In this retrospective cohort study of all HM3 patients in the period between November 2015 and October 2021, patients with and without prior TMCS were compared. Patients\' demographics, baseline clinical characteristics, laboratory tests, intraoperative variables, postoperative outcomes, and adverse events were collected from patient records. Results. The TMCS group showed an improvement in hemodynamics prior to LVAD implantation. Median TMCS duration was 19.5 (14-26) days. However, the TMCS group were more coagulopathic, had more wound infections, neurological complications, and more patients were on dialysis compared with patient without TMCS prior to HM3 implantation. Survival four years after HM3 implantation was 80 and 82% in the TMCS (N = 22) and non-TMCS group (N = 41), respectively. Conclusion. Patients on TMCS had an acceptable short and long-term survival and comparable to patients receiving HM3 without prior TMCS. However, they had a more complicated postoperative course.

OBJECTIVE: Cardiac surgery, post-cardiotomy cardiogenic shock (PCCS), and temporary mechanical circulatory support (tMCS) provoke substantial inflammation. We therefore investigated whether a selenium-based, anti-inflammatory strategy would benefit PCCS patients treated with tMCS in a post-hoc analysis of the sustain CSX trial.
METHODS: Post-hoc analysis of patients receiving tMCS for PCCS in the Sustain CSX trial, which investigated the effects of high-dose selenium on postoperative organ dysfunction in cardiac surgery patients.
METHODS: duration of tMCS therapy.
RESULTS: postoperative organ dysfunction and 30-day mortality.
RESULTS: Thirty-nine patients were treated with tMCS for PCCS. There was no difference in the median duration of tMCS between the selenium and the placebo group (3 days [IQR: 1-6] vs. 2 days [IQR: 1-7], p = 0.52). Median dialysis duration was longer in the selenium group (1.5 days [0-21.8] vs. 0 days [0-1.8], p = 0.048). There was no difference in 30-day mortality (53% vs. 41%, OR 1.44, 95% CI 0.32-6.47, p = 0.62).
CONCLUSIONS: In this explorative study, a perioperative high-dose selenium-supplementation did not show beneficial effects on organ dysfunctions and mortality rates in patients with PCCS receiving tMCS.

Red blood cells are destroyed when the shear stress in the blood pump exceeds a threshold, which in turn triggers hemolysis in the patient. The impeller design of centrifugal blood pumps significantly influences the hydraulic characteristics and hemolytic properties of these devices. Based on this premise, the present study employs a multiphase flow approach to numerically simulate centrifugal blood pumps, investigating the performance of pumps with varying numbers of blades and blade deflection angles. This analysis encompassed the examination of flow field characteristics, hydraulic performance, and hemolytic potential. Numerical results indicated that the concentration of red blood cells and elevated shear stresses primarily occurred at the impeller and volute tongue, which drastically increased the risk of hemolysis in these areas. It was found that increasing the number of blades within a certain range enhanced the hydraulic performance of the pump but also raised the potential for hemolysis. Moreover, augmenting the blade deflection angle could improve the hemolytic performance, particularly in pumps with a higher number of blades. The findings from this study can provide valuable insights for the structural improvement and performance enhancement of centrifugal blood pumps.
血泵中剪切应力超过阈值时红细胞会被破坏，进而引发患者出现溶血。离心式血泵叶轮结构设计对血泵的水力特性及溶血特性有着显著影响。基于此，本文采用多相流方法对离心式血泵进行数值模拟，探究了具有不同叶片数量及偏转角叶轮形式血泵的性能，分析了血泵的流场特性、水力性能以及溶血性能。数值模拟结果表明：血泵主要在叶轮及隔舌处出现了红细胞集聚现象及较大的切应力，导致此处溶血急剧增加；在一定范围内增加叶片数会提升血泵水力性能，同时也会增加溶血风险；增加叶片偏转角有助于提升血泵溶血性能，在叶片数较多时更为明显。本文研究结果可为离心式血泵的结构改进及性能改善提供参考。.

BACKGROUND: The treatment of patients with cardiogenic shock (CS) encompasses several health technologies including Impella pumps and venoarterial extracorporeal membrane oxygenation (VA-ECMO). However, while they are widely used in clinical practice, information on resource use and quality of life (QoL) associated with these devices is scarce. The aim of this study is, therefore, to collect and comparatively assess clinical and socioeconomic data of Impella versus VA-ECMO for the treatment of patients with severe CS, to ultimately conduct both a cost-effectiveness (CEA) and budget impact (BIA) analyses.
METHODS: This is a prospective plus retrospective, multicentre study conducted under the scientific coordination of the Center for Research on Health and Social Care Management of SDA Bocconi School of Management and clinical coordination of Istituto di Ricovero e Cura a Carattere Scientifico (IRCCS) San Raffaele Scientific Institute in Milan. The Impella Network stemmed for the purposes of this study and comprises 17 Italian clinical centres from Northern to Southern Regions in Italy. The Italian network qualifies as a subgroup of the international Impella Cardiac Surgery Registry. Patients with CS treated with Impella pumps (CP, 5.0 or 5.5) will be prospectively recruited, and information on clinical outcomes, resource use and QoL collected. Economic data will be retrospectively matched with data from comparable patients treated with VA-ECMO. Both CEA and BIA will be conducted adopting the societal perspective in Italy. This study will contribute to generate new socioeconomic evidence to inform future coverage decisions.
BACKGROUND: As of May 2024, most of the clinical centres submitted the documentation to their ethical committee (N=13; 76%), six centres received ethical approval and two centres started to enrol patients. Study results will be published in peer-reviewed publications and disseminated through conference presentations.

Upper hemi-sternotomy is a common approach for outflow graft anastomosis to the ascending aorta in minimally invasive left-ventricular assist device implantation. Right mini-thoracotomy may also be used, but use of robotic assistance has been reported only anecdotally. The aim of our study was to confirm the feasibility of robotically assisted suturing of the outflow graft anastomosis and to assess performance metrics for the robotic suturing part of the procedure. The procedure was carried out in eight cadaver studies by two surgeons. The assist device pump head was inserted through a left-sided mini-thoracotomy and the outflow graft was passed toward a right-sided second interspace mini-thoracotomy through the pericardium. After placement of a partial occlusion clamp on the ascending aorta, a longitudinal aortotomy was performed and the outflow graft to ascending aorta anastomosis was carried out robotically. The procedure was feasible in all eight attempts. The mean outflow graft anastomotic time was 20.1 (SD 6.8) min and the mean surgeon confidence and comfort levels to complete the anastomoses were 8.3 (SD 2.4) and 6.9 (SD2.2), respectively, on a ten-grade Likert scale. On open inspection of the anastomoses, there was good suture alignment in all cases. We conclude that suturing of a left-ventricular assist device outflow graft to the human ascending aorta is very feasible with good surgeon comfort. Anastomotic times are acceptable and suture placement can be performed with appropriate alignment.

UNASSIGNED: Caregivers of patients with advanced heart failure may experience burden in providing care, but whether changes in patient health status are associated with caregiver burden is unknown.
UNASSIGNED: This observational study included older patients (60-80 years old) receiving advanced surgical heart failure therapies and their caregivers at 13 US sites. Patient health status was assessed using the 12-item Kansas City Cardiomyopathy Questionnaire (range, 0-100; higher scores are better). Caregiver burden was assessed using the Oberst Caregiving Burden Scale, which measures time on task (OCBS-time) and task difficulty (OCBS-difficulty; range, 1-5; lower scores are better). Measurements occurred before surgery and 12 months after in 3 advanced heart failure cohorts: patients receiving long-term left ventricular assist device support; heart transplantation with pretransplant left ventricular assist device support; and heart transplantation without pretransplant left ventricular assist device support. Multivariable linear regression was used to identify predictors of change in OCBS-time and OCBS-difficulty at 12 months.
UNASSIGNED: Of 162 caregivers, the mean age was 61.0±9.4 years, 139 (86%) were female, and 140 (86%) were the patient\'s spouse. At 12 months, 99 (61.1%) caregivers experienced improved OCBS-time, and 61 (37.7%) experienced improved OCBS-difficulty (versus no change or worse OCBS). A 10-point higher baseline 12-item Kansas City Cardiomyopathy Questionnaire predicted lower 12-month OCBS-time (β=-0.09 [95% CI, -0.14 to -0.03]; P<0.001) and OCBS-difficulty (β=-0.08 [95% CI, -0.12 to -0.05]; P<0.001). Each 10-point improvement in the 12-item Kansas City Cardiomyopathy Questionnaire predicted lower 12-month OCBS-time (β=-0.07 [95% CI, -0.12 to -0.03]; P=0.002) and OCBS-difficulty (β=-0.09 [95% CI, -0.12 to -0.06]; P<0.001).
UNASSIGNED: Among survivors at 12 months, baseline and change in patient health status were associated with subsequent caregiver time on task and task difficulty in dyads receiving advanced heart failure surgical therapies, highlighting the potential for serial 12-item Kansas City Cardiomyopathy Questionnaire assessments to identify caregivers at risk of increased burden.
UNASSIGNED: URL: https://www.clinicaltrials.gov; unique identifier: NCT02568930.

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