A Simulation-Based Comparison of Human, Porcine and Ovine Pulmonary Artery Hemodynamics. Evaluating the Suitability of Large Animal Models for Endopulmonary Device Evaluation from a Hemodynamics Point of View.

In the field of cardiovascular device development, new devices such as heart valves, stents or pressure probes for long term heart failure monitoring are subject to animal trials to evaluate their safety and efficacy. For such applications, swine and sheep are the animal models of choice owed to their similarities to humans with regards to heart size, weight and ventricular kinetics. However, clinical aspects regarding the choice of animal model revolve mainly around anatomical similarities as well as the ability to induce the desired pathology.

A Novel CTC-Binding Probe: Enzymatic vs. Shear Stress-Based Detachment Approaches.

: Liquid biopsy is a minimally invasive alternative to tissue biopsy and is used to obtain information about a disease from a blood sample or other body fluids. In the context of cancer, circulating tumor cells (CTC) can be used as biomarkers to determine the nature of the tumor, its stage of progression, and the efficiency of the administered therapy through monitoring. However, the low concentration of CTCs in blood (1-10 cells/mL) is a challenge for their isolation.

Impact of calcifications on paravalvular leakage by transcatheter aortic valve prostheses: findings from a new in silico clinical trial framework.

Transcatheter aortic valve replacement (TAVR) has revolutionized the treatment of severe aortic stenosis, yet paravalvular leakage (PVL) remains a significant complication, associated with increased mortality. Clinical studies have identified correlations between PVL and both anatomical features and calcification patterns. Numerical simulations, particularly patient-specific models, offer valuable insights into PVL, but the limited scale of these studies hinders robust statistical analysis.

Increased extracellular volume after aortic valve replacement: a footprint of reverse ventricular remodeling that does not affect conduction velocity.

Background: Extracellular volume (ECV) determined by cardiovascular magnetic resonance (CMR) is considered a marker of diffuse myocardial fibrosis and a predictor of mortality. Using personalized computational models, we investigated the relationship between ECV, conduction velocity (CV), and cell radius in aortic stenosis (AS) patients.

Methods: CMR was performed on 12 AS patients (6 males, 6 females) before and 3 months after surgical aortic valve replacement (AVR).

Influences of mitral valve shape on transmitral hemodynamics before and after edge-to-edge repair: development of a reduced-order model.

Transcatheter edge-to-edge repair (TEER) is an effective treatment for mitral valve regurgitation in patients with high surgical risk, but predicting the hemodynamic outcomes is challenging. Reduced-order models (ROMs) show promise for post-TEER hemodynamic outcome predictions, but personalization of the ROM equations is essential for accurate simulations of mitral valve blood flow rates and pressure gradients during both diastole and systolic regurgitation. While the mitral valve orifice area is a common parameter used for ROM personalization, other aspects of the mitral valve shape are usually not considered.

Morphology and calcification characterization in patients undergoing TAVI: A 3D statistical shape modelling study.

Aortic stenosis (AS) is a common valvular disease becoming more prevalent globally due to the aging of the population. Transcatheter aortic valve implantation (TAVI) is a minimally invasive intervention indicated for AS patients as alternative to surgical replacement. TAVI is to date an established procedure.

Computational modelling of myocardial metabolism in patients with advanced heart failure.

Aims: Perturbations of myocardial metabolism and energy depletion are well-established hallmarks of heart failure (HF), yet methods for their systematic assessment remain limited in humans. This study aimed to determine the ability of computational modelling of patient-specific myocardial metabolism to assess individual bioenergetic phenotypes and their clinical implications in HF.

Methods And Results: Based on proteomics-derived enzyme quantities in 136 cardiac biopsies, personalized computational models of myocardial metabolism were generated in two independent cohorts of advanced HF patients together with sex- and body mass index-matched non-failing controls.

Age-dependent impairment of cardiac function and physical performance in male mice with diet-induced obesity.

Aging in the context of obesity exacerbates the risk of morbidity and mortality related to cardiovascular disease. However, the maladaptive responses in the heart that arise from prolonged obesity and the specific influence of biological age remain somewhat elusive. This study investigated the effects of diet-induced obesity (DIO) and aging on physical performance and cardiovascular function in mice.

Carotid atherosclerotic lesion analysis in 3D based on distance encoding in mesh representation.

Purpose: The purpose of this study is to support stroke risk analysis, evaluation of therapy effectiveness, and lesion progression through a comprehensive assessment of carotid atherosclerotic lesions in 3D based on automatic segmentation and visualization of quantitative parameters.

Methods: We propose a novel method for extracting the pathologically thickened regions from 3D vessel wall segmentations using distance encoding on the inner and outer wall mesh to enable atherosclerotic lesion analysis. A case-specific and constant threshold was evaluated and applied to extract lesions from a dataset of 202 T1-weighted black-blood MRI scans of subjects with up to 50% stenosis.

ElastoNet: Neural network-based multicomponent MR elastography wave inversion with uncertainty quantification.

Magnetic Resonance Elastography (MRE) quantifies soft tissue stiffness by measuring induced shear waves. MRE inversion techniques for parameter reconstruction are often affected by noise and compression waves. Neural network-based inversions have emerged as a possible solution to address these challenges.

Translation of Animal Study to Human: In Silico Based Development of Implantable Pulmonary Artery Pressure Sensor.

Implantable pulmonary artery pressure sensors (PAPS) might impose a flow-induced risk of thrombus formation in the pulmonary artery (PA). To assess this risk, an in silico study-enhanced animal study with 20 sensors implanted in 10 pigs had previously been conducted. In the in silico study, PAPS were virtually implanted mimicking real implantations, based upon data acquired by CT.

Managing withdrawals and exclusions of study participants in COVID-19-research by NUKLEUS.

Background: This article describes how withdrawals and exclusions of study participants can be managed in COVID-19-cohort studies by NUKLEUS (German: NUM Klinische Epidemiologie- und Studienplattform), using NAPKON (German: Nationales Pandemie Kohorten Netz). The aim of this manuscript was to describe, how partial withdrawals can be performed so that most of the data and bio-samples can be kept for research purposes.

Methods: The study has taken all signed informed consents (ICs) of study participants into account in order to develop a method how partial withdrawals can be developed and installed.

Impact of surgical ventricular restoration on intracardiac hemodynamics: An in silico study using CCT data.

Surgical ventricular restoration (SVR) excludes scarred myocardium after myocardial infarction to restore shape and contractility of dilated, aneurysmal left ventricles (LVs). Detailed changes in intracardiac hemodynamics following the surgery are not fully investigated. In this study, digital replicas of the patient's LV were used to study the hemodynamic impact of successful SVR.

Virtual Therapy Planning of Aortic Valve Replacement for Preventing Patient-Prosthesis Mismatch.

Background: Recent studies suggest that any degree of patient-prosthesis mismatch (PPM) increases morbidity and mortality after surgical aortic valve replacement (SAVR). We used computational fluid dynamics simulations to test the influence of prosthesis size and physical activity after SAVR.

Methods: In 10 patients with aortic valve stenosis, virtual SAVR was performed.

Experimental Investigation of the Applicability of the Stress-Based and Strain-Based Hemolysis Models for Short-Term Stress Peaks Typical for Rotary Blood Pumps.

Background: Although flow simulations have become more accurate, hemolysis prediction models still show large deviations from measured values in blood-carrying devices. To develop and validate more accurate models, specific hemolysis experiments are needed to determine the influence of parameters on hemolysis, such as stress type and exposure time typical for rotary blood pumps (RBPs).

Methods: In order to investigate the applicability of the hemolysis models to the flow in RBPs, this study performed experiments with human whole blood in three differently shaped flow channels that generate short-term stress peaks.

Numerical Assessment of the Efficiency of a New Minimally Invasive Probe for the Isolation of Circulating Tumor Cells.

Liquid biopsy, particularly the isolation of circulating tumor cells (CTCs) from blood, is a promising approach in the fight against cancer. However, the main reason why CTCs are hardly used as biomarkers in the clinic is their complicated isolation from the patient's blood. Existing ex vivo systems use a small volume of blood and can therefore only isolate very few CTCs.

Optimized outcome of the Ross procedure in children: single-centre experience†.

Objectives: The Ross procedure with autograft reinforcement has been proposed as a strategy to prevent autograft failure in adults, but outcome data in children during somatic growth remain limited. We investigated long-term outcomes following an individualized autograft reinforcement protocol to evaluate survival and reintervention rates.

Methods: Between January 1995 and December 2022, 233 patients <18 years [median age: 7 (1-13) years] underwent the Ross procedure, including 60 infants (26%).

Lumos: Software for Multi-level Multi-reader Comparison of Cardiovascular Magnetic Resonance Late Gadolinium Enhancement Scar Quantification.

Cardiovascular magnetic resonance imaging (CMR) offers state-of-the-art myocardial tissue differentiation. The CMR technique late gadolinium enhancement (LGE) currently provides the noninvasive gold standard for the detection of myocardial fibrosis. Typically, thresholding methods are used for fibrotic scar tissue quantification.

Assessing customized multivalent chemokine-binding peptide treatment in a murine model of coxsackievirus B3 myocarditis.

Myocarditis, an inflammatory disease of the heart muscle, is often triggered by viral infections. This inflammation, which can lead to severe cardiac dysfunction and adverse outcomes, is mediated by various CC and CXC chemokines that interact with receptors in a "one-to-many" fashion. Ticks have evolved chemokine-binding salivary proteins known as Evasins, which efficiently suppress inflammation.

Exploring the association between tissue sodium content, heart failure subtypes, and symptom burden: insights from magnetic resonance imaging.

Aims: Heart failure (HF) is a complex clinical syndrome with high morbidity and mortality, influenced significantly by sodium balance. Recently, magnetic resonance imaging (MRI) has emerged as a non-invasive method to evaluate tissue sodium load in HF patients. This proof-of-principle study investigates the association between tissue sodium content, assessed by MRI, and HF-related baseline parameters in an outpatient cohort of patients with chronic heart failure, including those with reduced ejection fraction (HFrEF), mildly reduced ejection fraction (HFmrEF), and preserved ejection fraction (HFpEF).

Real world federated learning with a knowledge distilled transformer for cardiac CT imaging.

Federated learning is a renowned technique for utilizing decentralized data while preserving privacy. However, real-world applications often face challenges like partially labeled datasets, where only a few locations have certain expert annotations, leaving large portions of unlabeled data unused. Leveraging these could enhance transformer architectures' ability in regimes with small and diversely annotated sets.

Multi-modal dataset creation for federated learning with DICOM-structured reports.

Purpose Federated training is often challenging on heterogeneous datasets due to divergent data storage options, inconsistent naming schemes, varied annotation procedures, and disparities in label quality. This is particularly evident in the emerging multi-modal learning paradigms, where dataset harmonization including a uniform data representation and filtering options are of paramount importance.Methods DICOM-structured reports enable the standardized linkage of arbitrary information beyond the imaging domain and can be used within Python deep learning pipelines with highdicom.

Comparative phenotyping of C57BL/6J substrains reveals distinctive patterns of cardiac aging.

Research in aging often refers to animal models, particularly C57BL/6J (B6J) mice, considered gold standard. However, B6J mice are distributed by different suppliers, which results in divers substrains exhibiting notable phenotypic differences. To ensure a suitable phenotype of cardiac aging, we performed heart analyses of young (5 months) and old B6J mice (24 months) from two substrains: B6JRj (Janvier) and B6JCrl mice (Charles River).

Autograft dilation after Ross procedure in children and young adults is mitigated by autograft reinforcement: A retrospective MRI study.

Limited magnetic resonance imaging (MRI) data on autograft dilatation following the Ross procedure in congenital cohorts presents challenges in understanding its evolution and impact on clinical outcomes. This study, spanning from February 2003 to December 2022, included patients under 40 years at the time of the Ross procedure, with MRI follow-ups assessing dimensions at key aortic sites. Among 307 patients, 132 MRIs were analyzed from 76 individuals, revealing that autograft z-scores increase primarily with time post-procedure (Coef.