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Contains fulltext : 293748.pdf (Publisher’s version ) (Open Access), Tissue-engineered heart valves (TEHVs) are emerging alternatives to current valve prostheses and prospectively a lifelong replacement. Calcification, a pathological complication for biological protheses, has been reported in preclinical TEHV studies. Systematic analysis of its occurrence is missing. This review aims to: 1) systematically review reported calcification of pulmonary TEHVs in large-animal studies; and 2) analyze the influence of engineering methodology (choice of scaffold material, cell preseeding) and animal model (animal species and age) on calcification. Baseline analysis included 80 studies, of which 41 studies containing 108 experimental groups were included in meta-analysis. Inclusion was low because only 55% of studies reported on calcification. Meta-analysis showed an overall average calcification event rate of 35% (95% CI: 28%-43%). Calcification was more prominent (P = 0.023) in the arterial conduit region (34%; 95% CI: 26%-43%) than in the valve leaflets (21%; 95% CI: 17%-27%), and was mostly (42% in leaflets, 60% in conduits) present in a mild form. Time-analysis showed an initial surge within 1 month after implantation, decreased calcification between 1 and 3 months, and then progression over time. There were no significant differences in degree of calcification between TEHV strategy nor animal models. Much variability between individual studies was observed in degree of calcification as well as quality of analysis and reporting thereof, hampering adequate comparisons between studies. These findings underline the need for improved analysis and better reporting standards of calcification in TEHVs. It also necessitates control-based research to further enlighten the risk of calcification for tissue-engineered transplants compared to current options. This can bring the field of heart valve tissue engineering forward toward safe clinical use.

01 augustus 2021, Item does not contain fulltext, BACKGROUND: Proton magnetic resonance spectroscopy ((1) H-MRS) of the human heart is deemed to be a quantitative method to investigate myocardial metabolite content, but thorough validations of in vivo measurements against invasive techniques are lacking. PURPOSE: To determine measurement precision and accuracy for quantifications of myocardial total creatine and triglyceride content with localized (1) H-MRS. STUDY TYPE: Test-retest repeatability and measurement validation study. SUBJECTS: Sixteen volunteers and 22 patients scheduled for open-heart aortic valve replacement or septal myectomy. FIELD STRENGTH/SEQUENCE: Prospectively ECG-triggered respiratory-gated free-breathing single-voxel point-resolved spectroscopy (PRESS) sequence at 3 T. ASSESSMENT: Myocardial total creatine and triglyceride content were quantified relative to the total water content by fitting the (1) H-MR spectra. Precision was assessed with measurement repeatability. Accuracy was assessed by validating in vivo (1) H-MRS measurements against biochemical assays in myocardial tissue from the same subjects. STATISTICAL TESTS: Intrasession and intersession repeatability was assessed using Bland-Altman analyses. Agreement between (1) H-MRS measurements and biochemical assay was tested with regression analyses. RESULTS: The intersession repeatability coefficient for myocardial total creatine content was 41.8% with a mean value of 0.083% ± 0.020% of the total water signal, and 36.7% for myocardial triglyceride content with a mean value of 0.35% ± 0.13% of the total water signal. Ex vivo myocardial total creatine concentrations in tissue samples correlated with the in vivo myocardial total creatine content measured with (1) H-MRS: n = 22, r = 0.44; P < 0.05. Likewise, ex vivo myocardial triglyceride concentrations correlated with the in vivo myocardial triglyceride content: n = 20, r = 0.50; P < 0.05. DATA CONCLUSION: We validated the use of localized (1) H-MRS of the human heart at 3 T for quantitati

Contains fulltext : 234054.pdf (Publisher’s version ) (Open Access), BACKGROUND: In response to an increased need for patient information in congenital heart disease, we previously developed an online, evidence-based information portal for patients with congenital aortic and pulmonary valve disease. To assess its effectiveness, a stepped-wedge cluster randomised trial was conducted. METHODS: Adult patients and caregivers of paediatric patients with congenital aortic and/or pulmonary valve disease and/or tetralogy of Fallot who visited the outpatient clinic at any of the four participating centres in the Netherlands between 1 March 2016-1 July 2017 were prospectively included. The intervention (information portal) was introduced in the outpatient clinic according to a stepped-wedge randomised design. One month after outpatient clinic visit, each participant completed a questionnaire on disease-specific knowledge, anxiety, depression, mental quality of life, involvement and opinion/attitude concerning patient information and involvement. RESULTS: 343 participants were included (221 control, 122 intervention). Cardiac diagnosis (p=0.873), educational level (p=0.153) and sex (p=0.603) were comparable between the two groups. All outcomes were comparable between groups in the intention-to-treat analyses. However, only 51.6% of subjects in the intervention group (n=63) reported actually visiting the portal. Among these subjects (as-treated), disease-specific knowledge (p=0.041) and mental health (p=0.039) were significantly better than in control subjects, while other baseline and outcome variables were comparable. CONCLUSION: Even after being invited by their cardiologists, only half of the participants actually visited the information portal. Only in those participants that actually visited the portal, knowledge of disease and mental health were significantly better. This underlines the importance of effective implementation of online evidence-based patient information portals in clinical practice.

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For in situ tissue engineering (TE) applications it is important that implant degradation proceeds in concord with neo-tissue formation to avoid graft failure. It will therefore be valuable to have an imaging contrast agent (CA) available that can report on the degrading implant. For this purpose, a biodegradable radiopaque biomaterial is presented, modularly composed of a bisurea chain-extended polycaprolactone (PCL2000-U4U) elastomer and a novel iodinated bisurea-modified CA additive (I-U4U). Supramolecular hydrogen bonding interactions between the components ensure their intimate mixing. Porous implant TE-grafts are prepared by simply electrospinning a solution containing PCL2000-U4U and I-U4U. Rats receive an aortic interposition graft, either composed of only PCL2000-U4U (control) or of PCL2000-U4U and I-U4U (test). The grafts are explanted for analysis at three time points over a 1-month period. Computed tomography imaging of the test group implants prior to explantation shows a decrease in iodide volume and density over time. Explant analysis also indicates scaffold degradation. (Immuno)histochemistry shows comparable cellular contents and a similar neo-tissue formation process for test and control group, demonstrating that the CA does not have apparent adverse effects. A supramolecular approach to create solid radiopaque biomaterials can therefore be used to noninvasively monitor the biodegradation of synthetic implants.

In cardiovascular surgery, reconstruction and replacement of cardiac and vascular structures are routinely performed. Prosthetic or biological materials traditionally used for this purpose cannot be considered ideal substitutes as they have limited durability and no growth or regeneration potential.

__Objectives:__ Aortic valve disease is the most frequent indication for heart valve replacement with the highest prevalence in elderly. Tissue-engineered heart valves (TEHV) are foreseen to have important advantages over currently used bioprosthetic heart valve substitutes, most importantly reducing valve degeneration with subsequent reduction of re-intervention. We performed early Health Technology Assessment of hypothetical TEHV in elderly patients (≥ 70 years) requiring surgical (SAVR) or transcatheter aortic valve implantation (TAVI) to assess the potential of TEHV and to inform future development decisions. __Methods:__ Using a patient-level simulation model, the potential cost-effectiveness of TEHV compared with bioprostheses was predicted from a societal perspective. Anticipated, but currently hypothetical improvements in performance of TEHV, divided in durability, thrombogenicity, and infection resistance, were explored in scenario analyses to estimate quality-adjusted life-year (QALY) gain, cost reduction, headroom, and budget impact. __Results:__ Durability of TEHV had the highest impact on QALY gain and costs, followed by infection resistance. Improved TEHV performance (− 50% prosthetic valve-related events) resulted in lifetime QALY gains of 0.131 and 0.043, lifetime cost reductions of €639 and €368, translating to headrooms of €3255 and €2498 per hypothetical TEHV compared to SAVR and TAVI, respectively. National savings in the first decade after implementation varied between €2.8 and €11.2 million (SAVR) and €3.2–€12.8 million (TAVI) for TEHV substitution rates of 25–100%. __Conclusions:__ Despite the relatively short life expectancy of elderly patients undergoing SAVR/TAVI, hypothetical TEHV are predicted to be cost-effective compared to bioprostheses, commercially viable and result in national cost savings when biomedical engineers succeed in realising improved durability and/or infection resistance of TEHV.

Contains fulltext : 204639.pdf (publisher's version ) (Open Access), BACKGROUND: With the implementation of transcatheter aortic valve replacement (TAVR) in lower-risk patients, evaluation of blood flow characteristics and the effect of TAVR on aortic dilatation becomes of considerable interest. We employed 4D flow MRI in the ascending aorta of patients after TAVR to assess wall shear stress (WSS) and compare blood flow patterns with surgical aortic valve replacement (SAVR) and age- and gender-matched controls. METHODS: Fourteen post-TAVR patients and ten age- and gender-matched controls underwent kt-PCA accelerated 4D flow MRI of the thoracic aorta at 3.0 Tesla. Velocity and wall shear stress was compared between the two groups. In addition, aortic flow eccentricity and displacement was assessed and compared between TAVR patients, controls and 14 SAVR patients recruited as part of an earlier study. RESULTS: Compared to controls, abnormally elevated WSS was present in 30+/-10% of the ascending aortic wall in TAVR patients. Increased WSS was present along the posterior mid-ascending aorta and the anterior distal-ascending aorta in all TAVR patients. TAVR results in eccentric and displaced flow in the mid- and distal-ascending aorta, whereas blood flow displacement in SAVR patients occurs only in the distal-ascending aorta. CONCLUSION: This study shows that TAVR results in increased blood flow velocity and WSS in the ascending aorta compared to age- and gender-matched elderly controls. This finding warrants longitudinal assessment of aortic dilatation after TAVR in the era of potential TAVR in lower-risk patients. Additionally, TAVR results in altered blood flow eccentricity and displacement in the mid- and distal-ascending aorta, whereas SAVR only results in altered blood flow eccentricity and displacement in the distal-ascending aorta. KEY POINTS: * TAVR results in increased blood flow velocity and WSS in the ascending aorta. * Longitudinal assessment of aortic dilatation after TAVR is warranted in the era of potential TAVR in lower

Background: As a living heart valve substitute with growth potential and improved durability, tissue-engineered heart valves (TEHVs) may prevent reinterventions that are currently often needed in children with congenital heart disease. We performed early health technology assessment to assess the potential cost-effectiveness of TEHVs in children requiring right ventricular outflow tract reconstruction (RVOTR). Methods: A systematic review and meta-analysis was conducted of studies reporting clinical outcome after RVOTR with existing heart valve substitutes in children (mean age ≤12 years or maximum age ≤21 years) published between January 1, 2000, and May 2, 2018. Using a patient-level simulation model, costs and effects of RVOTR with TEHVs compared with existing heart valve substitutes were assessed from a health care perspective applying a 10-year time horizon. Improvements in performance of TEHVs, divided in durability, thrombogenicity, and infection resistance, were explored to estimate quality-adjusted life year (QALY) gain, cost reduction, headroom, and budget impact associated with TEHVs. Results: Five-year freedom from reintervention after RVOTR with existing heart valve substitutes was 46.1% in patients less than or equal to 2 years of age and 81.1% in patients greater than 2 years of age. Improvements in durability had the highest impact on QALYs and costs. In the improved TEHV performance scenario (durability ≥5 years and –50% other valve-related events), QALY gain was 0.074 and cost reduction was €10,378 per patient, translating to maximum additional costs of €11,856 per TEHV compared with existing heart valve substitutes. Conclusions: This study showed that there is room for improvement in clinical outcomes in children requiring RVOTR. If TEHVs result in improved clinical outcomes, they are expected to be cost-effective compared with existing heart valve substitutes.

BACKGROUND: As a living heart valve substitute with growth potential and improved durability, tissue-engineered heart valves (TEHV) may prevent re-interventions that are currently often needed in children with congenital heart disease. We performed early Health Technology Assessment to assess the potential cost-effectiveness of TEHV in children requiring right ventricular outflow tract reconstruction (RVOTR). METHODS: A systematic review and meta-analysis was conducted of studies reporting clinical outcome after RVOTR with existing heart valve substitutes in children published between 1/1/2000-2/5/2018. Using a patient-level simulation model, costs and effects of RVOTR with TEHV compared to existing heart valve substitutes were assessed from a healthcare perspective applying a 10-year time horizon. Improvements in performance of TEHV, divided in durability, thrombogenicity, and infection resistance, were explored to estimate quality-adjusted life years (QALY) gain, cost reduction, headroom, and budget impact associated with TEHV. RESULTS: Five-year freedom from re-intervention after RVOTR with existing heart valve substitutes was 46.1% in patients ≤2 years old and 81.1% in patients >2 years old. Improvements in durability had the highest impact on QALYs and costs. In the ‘improved TEHV performance’ scenario (durability≥5 years and -50% other valve-related events), QALY gain was 0.074 and cost reduction was €10,378 per patient, translating to maximum additional costs of €11,856 per TEHV compared to existing heart valve substitutes. CONCLUSIONS: This study showed that there is room for improvement in clinical outcomes in children requiring RVOTR. If TEHV result in improved clinical outcomes, they are expected to be costeffective compared to existing heart valve substitutes.

Guidelines summarize and evaluate available evidence with the aim of assisting health professionals in selecting the best management strategies for an individual patient with a given condition. Guidelines and their recommendations should facilitate decision making of health professionals in their daily practice. However, the final decisions concerning an individual patient must be made by the responsible health professional(s) in consultation with the patient and caregiver as appropriate.

Contains fulltext : 182730.pdf (publisher's version ) (Open Access), OBJECTIVES: In response to an increased need for patient information on congenital heart disease in the Netherlands, we initiated a nationwide initiative to develop an online, evidence-based patient information portal, starting with a pilot project aimed at the subgroup of patients with congenital aortic and pulmonary valve disease. METHODS AND RESULTS: We developed an information portal that aims to (1) improve patient knowledge and involvement and to subsequently reduce anxiety and decisional conflict and improve mental quality of life and (2) to support physicians in informing and communicating with their patients. The information portal was developed according to the systematic International Patient Decision Aid Standards development process employing Delphi techniques by a multidisciplinary workgroup of pediatric and adult congenital cardiologists, a congenital cardiothoracic surgeon, a psychologist, an epidemiologist, a patient representative, and web and industrial design experts. First, patients and physicians were surveyed and interviewed to assess the current state of patient information and explore their preferences and needs to determine the focus for the development of the information portal. We found that patient knowledge and numeracy are limited, reliable information is scarce, physicians inform patients selectively and patient involvement is suboptimal, and there is a need for more reliable, tailored, and multi-faceted information. Based on the findings of these surveys and interviews, a patient-tailored information portal was designed that presents evidence-based disease- and age-specific medical and psychosocial information about diagnosis, treatment, prognosis, and impact on daily life in a manner that is comprehensible and digestible for patients and that meets the needs expressed by both patients and physicians. The effect of the website on patient outcome is currently being assessed in a multicenter stepped-wedge implementation trial. CONCLUSI