Using cryopreserved allogeneic pericardium to repair congenital heart defects in children.

Patches prepared from autologous, allogeneic, or xenogeneic tissues are widely used in the repair of congenital heart defects in children. Since 2002, cryopreserved allogeneic pericardial patches have been prepared in our institution as an alternative to commercially available patches. This study retrospectively reviewed donor and patient data concerning cryopreservation time and the clinical use of the pericardium in 382 children who were operated on at a single center between 2004 and 2021. There were 177 donors: 98 males and 79 females. The median donor age was 13 years (range: 1 month to 53 years) and the median cryopreservation time was 72 days (range: 3-685). There were 382 pediatric patients: 224 males and 158 females. The median patient age was 1 month (range: 3 days to 17.8 years). The patches were used for primary surgeries in 228 patients and for reoperations in 154. The patches were implanted into the right heart or venous circulation in 209 patients, the left heart or arterial circulation in 246 patients, and both sides of the circulatory system in 73. Extracardiac patch implantation was performed in 339 patients, intracardiac in 79 patients, and both intracardiac and extracardiac in 36 patients. Our study presents a single-center experience in the use of cryopreserved allogeneic pericardium. The pericardium can be used on the systemic and pulmonary sides of the circulatory system, in either extracardiac or intracardiac positions. However, there is no uniform strategy for selecting the "patch of choice" for correcting congenital heart defects in children, especially since there are few studies comparing several types of patches.

A Convolutional Neural Networks-Based Approach for Texture Directionality Detection.

The perceived texture directionality is an important, not fully explored image characteristic. In many applications texture directionality detection is of fundamental importance. Several approaches have been proposed, such as the fast Fourier-based method. We recently proposed a method based on the interpolated grey-level co-occurrence matrix (iGLCM), robust to image blur and noise but slower than the Fourier-based method. Here we test the applicability of convolutional neural networks (CNNs) to texture directionality detection. To obtain the large amount of training data required, we built a training dataset consisting of synthetic textures with known directionality and varying perturbation levels. Subsequently, we defined and tested shallow and deep CNN architectures. We present the test results focusing on the CNN architectures and their robustness with respect to image perturbations. We identify the best performing CNN architecture, and compare it with the iGLCM, the Fourier and the local gradient orientation methods. We find that the accuracy of CNN is lower, yet comparable to the iGLCM, and it outperforms the other two methods. As expected, the CNN method shows the highest computing speed. Finally, we demonstrate the best performing CNN on real-life images. Visual analysis suggests that the learned patterns generalize to real-life image data. Hence, CNNs represent a promising approach for texture directionality detection, warranting further investigation.

Cardiovascular magnetic resonance and transesophageal echocardiography in patients with prosthetic valve paravalvular leaks: towards an accurate quantification and stratification.

BACKGROUND: Objective assessment of prosthetic paravalvular leak (PVL) is complex and challenging even in transesophageal echocardiography (TEE). Our aim was to assess the value of cardiovascular magnetic resonance (CMR) in quantifying PVL in aortic (AVR) or mitral valve (MVR) replacement. METHODS: Thirty-one patients (62 ± 15.1 years, 63% males) with a preliminary diagnosis of significant PVL (AVR, n-23; MVR, n = 8) were recruited. The TEE PVL grading was based on the semi-quantitative (SQ) TEE according to the VARC II PVL classification (%PVL: mild < 10%; moderate 10%-30%; severe > 30%). Non-contrast CMR studies were acquired at 1.5 T with a quantitative approach (phase-contrast velocity encoded imaging). The CMR PVL severity was classified according to regurgitant fraction (RF: (1) mild ≤ 20%, (2) moderate 21%-39%, or (3) severe ≥ 40%). RESULTS: All patients revealed symptoms of heart failure (71%: New York Heart Association [NYHA] II; 91%: N-terminal pro-B-type natriuretic peptide [NT-proBNP] > 150 pg/ml) and typical cardiovascular disease risk factors. The SQ-TEE results revealed several categories: (1) mild (n = 5; 16%), (2) moderate (n = 21; 67%), and (3) severe (n = 5; 16%) PVL. However, CMR PVL RF reclassified the severity of PVL: (1) mild to moderate (in 80%), (2) moderate to severe (in 47%), and (3) severe to moderate (in 40%). The receiver operating characteristic analysis showed that SQ-TEE and CMR PVL-vol and -RF predicted the upper tertile of NT-proBNP (> 2000 pg/ml) with the best sensitivity for CMR parameters. CONCLUSION: The SQ-TEE showed moderate agreement with CMR and underestimated a considerable number of AVR or MVR-PVL.

Skin Lesion Detection Algorithms in Whole Body Images.

Melanoma is one of the most lethal and rapidly growing cancers, causing many deaths each year. This cancer can be treated effectively if it is detected quickly. For this reason, many algorithms and systems have been developed to support automatic or semiautomatic detection of neoplastic skin lesions based on the analysis of optical images of individual moles. Recently, full-body systems have gained attention because they enable the analysis of the patient's entire body based on a set of photos. This paper presents a prototype of such a system, focusing mainly on assessing the effectiveness of algorithms developed for the detection and segmentation of lesions. Three detection algorithms (and their fusion) were analyzed, one implementing deep learning methods and two classic approaches, using local brightness distribution and a correlation method. For fusion of algorithms, detection sensitivity = 0.95 and precision = 0.94 were obtained. Moreover, the values of the selected geometric parameters of segmented lesions were calculated and compared for all algorithms. The obtained results showed a high accuracy of the evaluated parameters (error of area estimation <10%), especially for lesions with dimensions greater than 3 mm, which are the most suspected of being neoplastic lesions.

[Contemporary dermatological methods of treating hirsutism]. / Wspólczesne dermatologiczne metody leczenia hirsutyzmu.

Hirsutism is a symptom of excessive androgen secretion in women, which in recent years is becoming more common. It is a problem of physical, mental and social background and patients always require application of an appropriate therapy. In addition to medical therapy, there are also other forms of treatment of hirsutism. These include the dermatological treatment using mechanical methods of removing unwanted hair. The aim of this work is to systematize the existing knowledge about treatment of hirsutism and suggest different patterns of treatment. Dermatological treatment is a very important complement to drug therapy. Its use allows for more rapid achievement of an external effect, and thus to improve the patients compliance. Due to the variety of symptoms in patients population therapy should be adapted to the needs of every patient.

Nitrogen Removal from Landfill Leachate Using Biochar Derived from Wheat Straw.

Landfill leachate (LLCH) disposal poses challenges due to high pollutant concentrations. This study investigates the use of biochar (BC) derived from wheat straw for nitrogen content reduction. Laboratory experiments evaluated BC's adsorption capacity (qm) for nitrogen removal from ammonium chloride solution (NH4Cl) and LLCH, along with testing isotherm models. The results demonstrated that BC was more efficient (95.08%) than commercial activated carbon AC (93.11%), the blank, in adsorbing nitrogen from NH4Cl. This superior performance of BC may be attributed to its higher carbon content (57.74%) observed through elemental analysis. Lower results for BC/LLCH may be due to LLCH's complex chemical matrix. The Langmuir isotherm model best described BC/NH4Cl adsorption (qm = 0.5738 mg/g). The AC/NH4Cl data also fitted into the Langmuir (R2 ˃ 0.9) with a qm of 0.9469 mg/g, and 26.667 mg/g (R2 ˂ 0.9) was obtained for BC/LLCH; the BC/LLCH also gave higher qm (R2 ˃ 0.9) using the Jovanovich model (which also follows Langmuir's assumptions). The mean energy of the adsorption values estimated for the AC/NH4Cl, BC/NH4Cl, and BC/LLCH processes were 353.55, 353.55, and 223.61 kJ/mol, respectively, suggesting that they are all chemisorption processes and ion exchange influenced their adsorption processes. The Freundlich constant (1/n) value suggests average adsorption for BC/LLCH. The BC/LLCH data followed the Harkins-Jura model (R2: 0.9992), suggesting multilayered adsorption (or mesopore filling). In conclusion, biochar derived from wheat straw shows promising potential for landfill leachate remediation, offering efficient nitrogen removal capabilities and demonstrating compatibility with various adsorption models. This research also lays the groundwork for further exploration of other biochar-based materials in addressing environmental challenges associated with landfill leachate contamination.

Artificial intelligence in the detection of skin cancer: State of the art.

The incidence of melanoma is increasing rapidly. This cancer has a good prognosis if detected early. For this reason, various systems of skin lesion image analysis, which support imaging diagnostics of this neoplasm, are developing very dynamically. To detect and recognize neoplastic lesions, such systems use various artificial intelligence (AI) algorithms. This area of computer science applications has recently undergone dynamic development, abounding in several solutions that are effective tools supporting diagnosticians in many medical specialties. In this contribution, a number of applications of different classes of AI algorithms for the detection of this skin melanoma are presented and evaluated. Both classic systems based on the analysis of dermatoscopic images as well as total body systems, enabling the analysis of the patient's whole body to detect moles and pathologic changes, are discussed. These increasingly popular applications that allow the analysis of lesion images using smartphones are also described. The quantitative evaluation of the discussed systems with particular emphasis on the method of validation of the implemented algorithms is presented. The advantages and limitations of AI in the analysis of lesion images are also discussed, and problems requiring a solution for more effective use of AI in dermatology are identified.

Comparable clinical safety and efficacy of biodegradable versus durable polymer paclitaxel eluting stents despite shorter dual antiplatelet therapy: insights from a multicenter, propensity score-matched registry.

BACKGROUND: The biodegradable polymer drug-eluting stents have been proposed as an alternative to durable polymer DES, theoretically improving vessel healing and reducing the need for prolonged double anti platelet therapy (DAPT), however clinical significance of this technology is under debate. Therefore, we sought to compare the clinical outcomes of two Paclitaxel eluting stents (PES) containing different polymer-based eluting matrices. METHODS: In this multicenter registry of 392 consecutive patients who underwent PCI between June 2006 and September 2008, we included patients with stable angina or NSTE-ACS displaying at least one significant lesion (>50% diameter stenosis) in native coronary arteries. RESULTS: Biodegradable polymer PES (BP-PES, LUC Chopin(2) , Balton, Poland) was implanted in 206 patients, whereas durable polymer PES (DP-PES, Taxus, Boston Scientific, USA) was implanted in 186 patients. There were no significant differences in baseline characteristics between groups with the exception of increased diabetes and number of lesions for BP-PES. In risk-unadjusted analysis at 1-year follow-up, there were no significant differences in TLR (BP-PES: 8.4% vs. DP-PES: 6%; P = 0.36), TVR (BP-PES: 11.1% vs. DP-PES: 8.4%; P = 0.36) and incidence of stent thromboses (BP-PES: 2.15% vs. DP-PES: 3.4%; P = 0.42) between groups. There was also no difference in MACCE between groups (17.6% vs. 14.4%, P = 0.49). The mean dual antiplatelet therapy (DAPT) compliance at 1 year was 77% for BP-PES versus 92% for DP-PES (P = 0.03). Kaplan-Meier analysis showed a significantly higher long-term stroke free survival in BP-PES (P = 0.04). After adjustment, this was sustained with an additional tendency toward higher MI free survival for BP-PES (P = 0.059). CONCLUSIONS: In this observational analysis, BP-PES were comparable to DP-PES, with regard to incidence of repeated revascularizations, stent thromboses and MACCE despite earlier DAPT discontinuation.

SOCS and diabetes--ups and downs of a turbulent relationship.

Diabetes mellitus is one of the most emerging diseases threatening the present world. Thus, intensive investigations are carried out to better understand the mechanisms occurring in type 1 (T1D) and 2 (T2D) diabetes, and to elaborate more potent methods to fight the disease. In this aspect, the suppressors of cytokine signalling (SOCS) are one of the most studied factors of recent years. SOCS proteins have been discovered as cytokine pathway inhibitors; however, presently, their influence seems wider. Most of the known SOCS proteins are involved in the modulation of the development of insulin resistance, ß-cell failure and eventually T1D and T2D. They are also involved in complications related with diabetes, such as retinopathy, nephropathy and cardiomyopathy. In T1D, SOCS proteins regulate ß-cell mass, mediate resistance to damaging factors and improve pancreatic islet graft survival. Regarding insulin resistance and T2D, SOCS proteins take part in mediating signals produced by diabetogenic substances and regulate insulin receptor functioning, affecting insulin sensitivity. However, not all of the present data are consistent, and thus, further studies are required. Finally, for several pharmacologically active substances of importance regarding the treatment of diabetes, SOCS-modulating properties have already been described. Here, we review the findings of SOCS-diabetes relations of the last decade.

[Contemporary pharmacological methods of treating hirsutism]. / Najnowsze farmakologiczne metody leczenia hirsutyzmu.

Hirsutism is a symptom of excessive androgen secretion in women, which in recent years is becoming more common. It is a problem of physical, mental and social background and patients always require application of an appropriate therapy Today's medicine offers a wide variety of treatments for the disease, each of which has a different efficiency. This article describes the pharmacological treatment of hirsutism using, among others: antiandrogenic drugs, corticosteroids and oral contraceptives. We performed an extensive literature looking for articles dealing with various forms of hirsutism treatment, most important items were selected and compiled in this work. Modem medicine distinguishes many forms of hirsutism treatment. A very important form of treatment for this condition is the use of pharmacological agents. Their diversity allows optimal adjustment of therapy to the requirements and needs of the patient. Drug therapy is effective, however, in most cases also requires a dermatological treatment.

Revealing the Adverse Impact of Additive Carbon Material on Microorganisms and Its Implications for Biogas Yields: A Critical Review.

Biochar could be a brilliant additive supporting the anaerobic fermentation process. However, it should be taken into account that in some cases it could also be harmful to microorganisms responsible for biogas production. The negative impact of carbon materials could be a result of an overdose of biochar, high biochar pH, increased arsenic mobility in the methane fermentation solution caused by the carbon material, and low porosity of some carbon materials for microorganisms. Moreover, when biochar is affected by an anaerobic digest solution, it could reduce the biodiversity of microorganisms. The purpose of the article is not to reject the idea of biochar additives to increase the efficiency of biogas production, but to draw attention to the properties and ways of adding these materials that could reduce biogas production. These findings have practical relevance for organizations seeking to implement such systems in industrial or local-scale biogas plants and provide valuable insights for future research. Needless to say, this study will also support the implementation of biogas technologies and waste management in implementing the idea of a circular economy, further emphasizing the significance of the research.

Particle Image Velocimetry of 3D-Printed Anatomical Blood Vascular Models Affected by Atherosclerosis.

Improvements in the diagnosis and treatment of cardiovascular diseases facilitate a better understanding of the ongoing process. The study of biomedical fluid dynamics using non-intrusive visualizing methods on a micro-scale has become possible using a proper 3D printing process. The computed tomography scan of a patient with atherosclerosis was processed, and a 3D-printed artery with an inlet diameter of 4.2 mm was developed and measured using three different constant flow rates. To mimic blood, a solution of glycerin and water was used. The procedure to obtain a proper 3D-printed model using low-force stereolithography technology with high-quality optical access usable for PIV was described and discussed. The paper presents the results of PIV as multi-stitched, color-coded vector maps from the axis cross section along the whole 3D-printed model. The obtained data allowed a resolution of 100 × 100 µm per single vector to be achieved. Furthermore, the results of the stitched 16 base images of the artery and the 3D-printed model prepared were included. The results of this study show that 3D prints allow for the creation of the desired geometry and can be used to investigate severe pathologies of the human circulatory system. The strengths and weaknesses of this methodology were discussed and compared to other techniques used to obtain transparent objects.

Hemolysis of red blood cells in blood vessels modeled via computational fluid dynamics.

The research aims to verify the universal relationship between vessel shape and the risk of hemolysis using a rheological model of blood reflecting the physiological processes related to blood for any blood vessel. Blood is a multi-component fluid, the rheology of which depends on many factors, such as the concentration of red blood cells and local shear stress, which significantly affect the process of hemolysis. Blood rheology models used so far cannot be used for all flows and geometries. Therefore, a new rheology model has been introduced suitable for modeling hemolytic flows observed in arteries with atherosclerotic lesions in the in vivo environment. The previously presented model also has advantages in modeling local viscosity in stenosis. Geometries of the blood vessels from computed tomography scans and simplified models of the actual arteries observed during medical procedures were used in the calculations. Population Balance Based Rheology model predicts the concentration of single, deagglomerated red blood cells and the concentration and size of red blood cell agglomerates, which affect blood rheology and hemolysis. Based on the simulations carried out, a correlation was found between the shape of the vessel cavity and the risk of hemolysis. Presented results can be used in the future to create a correlation between the shape of the atherosclerotic lesions and the risk of hemolysis in the blood to make an initial risk assessment for a given patient.

Mitral Paravalvular Leak 3D Printing from 3D-Transesophageal Echocardiography.

BACKGROUND: Paravalvular leaks can be detected in almost 15% of patients after mitral valve prosthesis implantation. This complication can result in congestive heart failure and hemolysis. Despite advancements in non-invasive imaging, percutaneous closure of paravalvular leaks is not always successful. Therefore, efforts are made to improve treatment outcomes by using 3D-printed models of defects as pre-procedural support for interventional cardiologists. METHODS: Retrospectively, 3D-transesophageal echocardiography recordings of 8 patients with clinically significant mitral paravalvular leaks were analyzed. Qlab Software was used to export DICOM images of each paravalvular leak channel, including surrounding tissue. Image segmentation was performed in 3D Slicer, a free, open-source software package used for imaging research. Models were printed to actual size with the poly jet Stratasys Objet 30 printer with a transparent, rigid material. RESULTS: Duration of model preparation and printing, as well as the total cost, was calculated. Mean total time of model preparation was 430.5 ± 196 minutes. CONCLUSION: 3D-printing from 3D-transesophageal echocardiography is technically feasible. Both shape and location of paravalvular leaks are preserved during model preparation and printing. It remains to be tested if 3D-printing would improve outcomes of percutaneous paravalvular leaks closure.

Prediction of Hemodynamic-Related Hemolysis in Carotid Stenosis and Aiding in Treatment Planning and Risk Stratification Using Computational Fluid Dynamics.

Atherosclerosis affects human health in many ways, leading to disability or premature death due to ischemic heart disease, stroke, or limb ischemia. Poststenotic blood flow disruption may also play an essential role in artery wall impairment linked with hemolysis related to shear stress. The maximum shear stress in the atherosclerotic plaque area is the main parameter determining hemolysis risk. In our work, a 3D internal carotid artery model was built from CT scans performed on patients qualified for percutaneous angioplasty due to its symptomatic stenosis. The obtained stenosis geometries were used to conduct a series of computer simulations to identify critical parameters corresponding to the increase in shear stress in the arteries. Stenosis shape parameters responsible for the increase in shear stress were determined. The effect of changes in the carotid artery size, length, and degree of narrowing on the change in maximum shear stress was demonstrated. Then, a correlation for the quick initial diagnosis of atherosclerotic stenoses regarding the risk of hemolysis was developed. The developed relationship for rapid hemolysis risk assessment uses information from typical non-invasive tests for treated patients. Practical guidelines have been developed regarding which stenosis shape parameters pose a risk of hemolysis, which may be adapted in medical practice.

Outcomes of Transannular Repair of Tetralogy of Fallot With a Contegra® Monocuspid Patch.

BACKGROUND: Surgical repair of tetralogy of Fallot (ToF) depends on the anatomical variations of the heart defect. A group of patients with a hypoplastic pulmonary valve annulus required a transannular patch. This study aimed to evaluate the early and late outcomes of ToF repair with a transannular Contegra® monocuspid patch in a single center. METHODS: A retrospective review of medical records was conducted. This study included 224 children with a median age of 13 months who underwent ToF repair with a Contegra® transannular patch in over 20 years of observation. The primary outcomes were hospital mortality and need for early reoperations. The secondary outcomes were late death and event-free survival. RESULTS: The hospital mortality in our group was 3.1%, whereas two patients required early reoperation. Three patients were excluded from the study because follow-up data were not available. In the remaining group of patients (212 patients), the median follow-up was 116 (range, 1-206) months. One patient died because of sudden cardiac arrest at home six months after surgery. Event-free survival was observed in 181 patients (85.4%), whereas the remaining 30 patients (14.1%) required graft replacement. The median time to reoperation was 99 (range, 4-183) months. CONCLUSIONS: Although surgical treatment of ToF has been performed for more than 60 years worldwide, the optimal approach in children with a hypoplastic pulmonary valve annulus remains debatable. Among options, the Contegra® monocuspid patch can be effectively used in transannular repair of ToF with good long-term results.

3D printing from transesophageal echocardiography for planning mitral paravalvular leak closure - feasibility study.

Introduction: Transcatheter closure of paravalvular leak (PVL) is still a demanding procedure due to the complex anatomy of PVL channels and risk of interference between the implanted occluder and surrounding structures. Efforts are made to improve procedural outcomes in transcatheter structural heart interventions by establishing treatment strategy in advance with the use of 3D-printed physical models based on data obtained from cardiac computed tomography (CT) studies. Aim: In this feasibility study 3D printing of PVL models based on data recorded during transesophageal echocardiography (TEE) examinations was evaluated. Material and methods: 3D-TEE data of patients with significant PVL around mitral valve prostheses were used to prepare 3D models. QLab software was used to export DICOM images in Cartesian DICOM format of each PVL with the surrounding tissue. Image segmentation was performed in Slicer, a free, open-source software package used for imaging research. Models were printed to actual size with the Polyjet printer with a transparent, rigid material. We measured dimensions of PVLs both in TEE recordings and printed 3D models. The results were correlated with sizes of occluding devices used to close the defects. Results: In 7 out of 8 patients, there was concordance between procedurally implanted occluders and pre-procedurally matched closing devices based on 3D-printed models. Conclusions: 3D-printing from 3D-TEE is technically feasible. Both shape and location of PVLs are preserved during model preparation and printing. It remains to be tested whether 3D printing would improve outcomes of percutaneous PVL closure.

Effects of modelling studies on controlled drainage in agricultural land on reduction of outflow and nitrate losses-a meta-analysis.

A review with meta-analysis of outflow and nitrate loss reduction in controlled drainage (CD) vs conventional, free drainage (FD) was carried out in the study. Since the results of experimental field studies usually cover short periods of data collection, hence in this paper, meta-analyses were based on model studies that usually cover a longer time range. The databases Web of Science and Scopus were searched for eligible English articles, published until December 2020, that describe the quantity and quality of drainage water. The meta-analysis of outflow and nitrate loss reduction in CD vs FD using the mean difference (MD) with a confidence interval (CI) of 95%. The influence of each study was measured through heterogeneity, sensitivity analyses and publication bias using STATISTICA (version 13.3) for all analyses. Of the 107 works identified, 18 were finally included in the analysis based on established criteria required for an appropriate meta-analysis. In general the results indicate a reduction in average drainage outflow of 30.5% (MD = -71.26 mm; 95% CI, -103.49 --39.04; p = 0.000) in arable land with CD in comparison to FD practice. In the case of nitrate load the reduction was 33.61% and in the drainage water there was lower content in CD practice by an average of 8.36 kg NO3 ha-1year-1 (95% CI, -9.93 --6.79; p = 0.000). Subgroup analysis of two meta-analyses indicates that the results concerning these associations may vary with the calculated weight for each article, in which the number of years of study had the most significant impact.

Quality of life after percutaneous paravalvular leak closure - a prospective registry.

Introduction: Presence of paravalvular leaks (PVLs) can lead to heart failure, which decreases quality of life (QoL). Percutaneous closure is becoming the first-line treatment of PVLs, but whether such a procedure could improve QoL in these patients has never been examined. Aim: To examine changes in scores of the Minnesota Living with Heart Failure Questionnaire (MLHFQ) and Kansas City Cardiomyopathy Questionnaire (KCCQ) after percutaneous PVL closure. Material and methods: Forty subjects with heart failure symptoms and at least moderate PVL were included in this prospective registry. QoL was assessed at baseline and during a 12-month follow-up after percutaneous PVL closure by MLHFQ and KCCQ questionnaires. Changes in NT-proBNP and lactate dehydrogenase (LDH) levels were also analyzed. Results: Technical success (TS) was achieved in 97.5% of cases and procedural success (PS) in 85% of cases. In the group with PS a significant decrease in MLHFQ score as well as an increase in scores of all KCCQ domains was observed. No statistically significant changes were observed in the group without PS, mainly due to the small sample size. Conclusions: Percutaneous PVL closure is associated with better QoL during a 12-month follow-up provided PS was achieved. Due to the low number of subjects in whom PS was not achieved, it is not possible to determine the influence of a failed procedure in this group of patients.

Parameters of Flow through Paravalvular Leak Channels from Computational Fluid Dynamics Simulations-Data from Real-Life Cases and Comparison with a Simplified Model.

BACKGROUND: Shear forces affecting erythrocytes in PVL channels can be calculated with computational fluid dynamics (CFD). The presence of PVLs is always associated with some degree of hemolysis in a simplified model of the left ventricle (LV); however, data from real-life examples is lacking. METHODS: Blood flow through PVL channels was assessed in two variants. Firstly, a PVL channel, extracted from cardiac computed tomography (CCT), was placed in a simplified model of the LV. Secondly, a real-life model of the LV was created based on CCT data from a subject with a PVL. The following variables were assessed: wall shear stress (τw) shear stress in fluid (τ), volume of PVL channel with wall shear stress above 300 Pa (V300), duration of exposure of erythrocytes to shear stress above 300 Pa (Vt300) and compared with lactate dehydrogenase (LDH) activity levels. RESULTS: τw and τ were higher in the simplified model. V300 and Vt300 were almost identical in both models. CONCLUSIONS: Parameters that describe blood flow through PVL channels can be reliably assessed in a simplified model. LDH levels in subjects with PVLs may be related to V300 and Vt300. Length and location of PVL channels may contribute to a risk of hemolysis in mitral PVLs.