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There is a known correlation between myocardial steatosis and heart function, but it is unclear how left ventricular diastolic function worsens over time in the myocardial steatosis setting. We sought to investigate whether intramyocardial fat deposition affects diastolic function over time. This was a retrospective analysis of patients who had undergone 1-3 echocardiography assessments between April 2011 and April 2017. Patients were divided into two groups: those with the presence of myocardial fat deposition in the left ventricular myocardium (assessed by having tissue within any 10-mm2 region with computed tomography values between - 190 and - 30 Hounsfield units; + MF), and those with absence of deposition not meeting the threshold (- MF). The rates of change of the standard early diastolic mitral annulus velocity (e') and the transmitral early peak velocity (E)/e' ratio at the second and third echocardiograph assessments were calculated relative to baseline. In total, 125 patients were eligible (+ MF, n = 39; - MF, n = 86) for inclusion. Compared with the - MF group, e' was significantly lower and E/e' was significantly higher in the + MF group at each scan timepoint, even when adjusted for body mass index and sex. A significant average decrease in e' and increase in E/e' was also observed in the + MF group across all scans compared with the - MF group. Myocardial steatosis was associated with an acceleration of decreased left ventricular diastolic function over time.

Assessment of segmental myocardial strain is a promising and relevant direction in the diagnosis of early impairments of left ventricular (LV) contractility in children with hypertrophic cardiomyopathy (HCM). Objective of the study: to assess the indicators of segmental myocardial strain in children with HCM. Materials and methods of research: prospective, open-label, nonrandomized, controlled. 61 patients with asymmetric HCM aged 7 to 17 years (median 9 [7,6; 13,2]) underwent echocardiography according to the standard technique with the determination of segmental longitudinal, radial, circular LV myocardium in 2D speckle tracking mode. 45 (74%) children had a non-obstructive form (NF) of HCM, 16 (26%) children had an obstructive form (OF). Obstruction was detected at the level of the LV outflow tract with a pressure gradient of 30-50 mm Hg. Results: when assessing segmental myocardial strain, a decrease in longitudinal strain was found less than the normative values in the antero-septal, anterior, antero-lateral segments in children with NF HCM with a compensatory increase in strain values in the contralateral segments (inferior septal, inferior lateral and lower ). In similar segments in children with OF, there was a significant decrease in deformity, while in the contralateral segments a less pronounced compensatory increase in deformity was determined, as well as a decrease in the minimum values of strain indicators. Assessment of segmental radial and circular strain, a statistically significant predominance of indicators in all segments, except for anterolateral, in the group with NF compared to the OF HCM was determined. A decrease in strain in the antero-septal, anterior, antero-lateral segments was found, but less pronounced compared to the indicators of longitudinal strain, as well as a compensatory increase in strain in the antero-septal values in the contralateral segments (inferior septal, inferior lateral and inferior). It has been found that the assessment of global strain values widely used in clinical practice might not be optimal enough, since too many segmental strain values are discarded and averaged, which are unevenly distributed, and therefore the assessment of strain in each segment of the myocardium in children with an asymmetric form of HCM acquires important diagnostic value. Conclusion: changes in the indicators of segmental myocardial strain reflect violations of LV contractile function and are most pronounced in OF compared with NF HCM. Their study in children is important for the timely initiation of therapy and improving the prognosis of the disease.

Мета. Вивчення особливостей морфофункціонального стану міокарда лівого шлуночка та загальних сонних артерій за даними ехокардіодопплерографії у дітей, хворих на муковісцидоз. Матеріали та методи. Обстежено 72 дитини, хворі на муковісцидоз. Для діагностики доклінічної стадії діастолічної дисфункції лівого шлуночка визначали функціональний індекс відповідності (ФІВ) за методикою А.Н. Розенбаума та В.Т. Коваля (2010). Результати. Результати проведеного дослідження свідчили про розвиток ремоделювання міокарда лівого шлуночка у 58 % хворих на муковісцидоз, серед варіантів якого переважала ексцентрична гіпертрофія. Виявлені зміни посилювалися при збільшенні тяжкості перебігу захворювання. Аналіз діастолічної функції лівого шлуночка за стандартною методикою в групі хворих на муковісцидоз не виявив суттєвих відмінностей від показників контрольної групи. Розрахунок ФІВ показав, що у 37,5 % дітей, хворих на муковісцидоз, відбувалося його зниження відносно значень контрольної групи. Це свідчило про формування діастолічної дисфункції лівого шлуночка, що прогресувала в динаміці захворювання. Найбільш виражені зміни ФІВ виявлялися при концентричній гіпертрофії міокарда лівого шлуночка та при тяжкому перебігу захворювання. Висновки. Встановлена морфофункціональна перебудова лівих відділів серця у дітей, хворих на муковісцидоз, відбувалася на фоні ремоделювання та гемодинамічних змін на рівні загальних сонних артерій.

The safety and efficacy of intravenous insulin injection coupled with subsequent milk consumption was evaluated for high-quality cardiac viability F-18-fluorodeoxyglucose (18F-FDG) images. A total of 328 patients with known/suspected coronary artery disease received intravenous insulin injection with or without subsequent milk consumption for cardiac 18F-FDG imaging. When blood glucose levels had decreased by ≥ 20%, 18F-FDG was injected. Patients were scored for hypoglycemic symptoms using a 10-point scale (discomfort: 0, none; 1 to 3, mild; 4 to 6, moderate; 7 to 9, severe). An insulin-related hypoglycemic event was defined as an increased symptomatic score following insulin injection. The number of hypoglycemic events was significantly lower in the milk consumption group than in the group that did not (24/164 vs. 51/164, P

The variability of physiologic 18F-FDG uptake in the myocardium has hampered the accurate evaluation of cardiac glucose metabolism. We investigated the effects of multiple factors, including fasting duration and physical activity, on the physiologic uptake of 18F-FDG by the myocardium in healthy participants. A total of 446 participants (predominantly male, 91%) in a health screening program were included in this retrospective study. For the visual analysis of myocardial 18F-FDG uptake, the participants were categorized into three groups according to qualitative visual scales (QVS). For the quantitative analysis, the maximum SUV of the left ventricular myocardium was measured. Significant differences were observed in fasting duration (p 6% (p = 0.005) showed significant association with myocardial FDG uptake in the Chi-squared test. The median value of fasting duration decreased significantly as the QVS of the myocardium increased. Twenty-nine of the 31 participants (93.5%) who fasted for 21.5 h or more showed a suppressed FDG uptake (mean SUVmax = 2.1). In multivariate logistic regression analysis, fasting duration (OR = 0.74, 95% CI 0.69–0.80, p 6% (OR = 0.29, 95% CI: 0.12 – 0.66, p = 0.004), uric acid (OR = 0.82, 95% CI 0.68–1.00, p = 0.049) and regular exercise with vigorous activity (OR = 1.75, 95% CI 1.13–2.70, p = 0.012) were significant factors for physiologic myocardial FDG uptake. Reduced physiologic 18F-FDG uptake of the myocardium was associated with longer fasting duration, higher level of HbA1c, and less frequency of regular exercise with vigorous activity. For the preparation of cardiac 18F-FDG PET, inclusion of longer fasting duration (more than 18 h) might be necessary for the adequate suppression of physiologic 18F-FDG myocardial uptake.

Introduction . To determine the relevant indicators of strain and strain rate of the left ventricular myocardium in children and adolescents. Materials and methods. Have been examined 67 patients form aged from 7 up to 17 years old. 1-st group – 30 children from 7 to 11 years old; 2-nd group – 37 adolescents from 12 to 17 years old. Аt an echocardiographic examination the systolic function of the left ventricle was determined: ejection and shortening fractions, in 2D-speckle-tracking mode – global and segmental longitudinal, circular and radial strain and strain rates. Results . Have been studied the relevant indicators of global and segmental longitudinal, radial, circular deformities of the left ventricular myocardium and their rates in healthy children and adolescents. A statistically significant increase in global and segmental longitudinal strain, radial and circular strain rates in the 2-nd group compared with the 1-st group had revealed. Had found that the uniform distribution of indicators in the ranges of confidence intervals, noted in the assessment of global radial strain and circular strain rate, as well as a statistically significant predominance of strain indicators in the subendocardial layers compared with the subepicardial layers of the myocardium left ventricle. Conclusions. 1. In adolescents 12–17 years old, compared with children 7–11 years old, there is a statistically significant predominance of global and segmental longitudinal strain, radial and circular strain rates of the left ventricular myocardium. Radial strain and circular strain rate of the left ventricular myocardium are the most uniform in contrast to other indicators of strain. 2. In healthy children and adolescents, had observed statistically significant higher strain and strain rate in the subendocardial layer compared to the subepicardial layer of the myocardium. 3. The obtained indicators of global and segmental myocardial strain can serve as normative for children and adolescents in assessing the systolic function of the left ventricle.

Objective Forward-projected Model-based Iterative Reconstruction SoluTion (FIRST) is a novel reconstruction method. We investigated the improvement in the diagnostic performance for the detection of abnormal late enhancement (LE) in left ventricular myocardium (LVM) using a new-generation 320-slice computed tomography (CT) device with FIRST. Methods This is a retrospective study that included 100 adult patients who underwent cardiac CT including a late phase scan and magnetic resonance imaging (MRI) within 3 months. The first 50 consecutive patients (first-generation group) underwent first-generation 320-slice CT without FIRST, and the next 50 consecutive patients (second-generation group) underwent second-generation 320-slice CT with FIRST. We compared the diagnostic performance of the first- and second-generation 320-slice CT with FIRST with MRI as a reference standard to detect LE in LVM. Results In the patient-based analysis, the sensitivity, specificity, positive predictive value, negative predictive value, and overall accuracy of detection of LE on CT were 79%, 90%, 92%, 76%, and 84%, respectively, in the first-generation group and 97%, 84%, 91%, 94%, and 92%, respectively, in the second-generation group. The sensitivity was significantly higher in the second-generation group than in the first-generation group (p=0.049). In the segment-based analysis, the sensitivity, specificity, positive predictive value, negative predictive value, and overall accuracy of detection of LE on CT were 69%, 96%, 83%, 92%, and 90%, respectively, in the first-generation group and 87%, 94%, 84%, 95%, and 92%, respectively, in the second-generation group. The sensitivity and negative predictive value were significantly higher in the second-generation group than in the first-generation group (p

The results of an investigation intended to develop a mathematical model representation of the left ventricular myocardium in the polar bull’s eye map mode are presented. Comparison of images obtained using the numerical simulation and the cases in clinical practice allows evaluating possible errors and discrepancies of reconstruction in the single-photon emission computed tomography.

The aim was to determine the pathogenetic features of the NO system in the myocardium of the left ventricle in the rats with endocrine-salt hypertension.Material and methods. The experiment was conducted on 20 male rats 220-290 g weight, 6–10 months old which were divided into 2 experimental groups: 1st – the control group (10 intact normotensive male Wistar rats); 2nd – 10 male Wistar rats with endocrine-salt arterial hypertension. Systolic and diastolic BP levels were measured in all the rats using a system of non-invasive arterial pressure measurement BP-2000. The objects of study in the experimental animals were blood plasma in which the nitrotyrosine level was measured, and the fragment of left ventricle, which was divided into two parts, one of which was homogenized using a Silent Crusher S homogenizer (Heidolph, Germany), in which nitrites level was determined. Concentration of immunoreactive material to NOS isoforms was detected with immunofluorescence method. The study of NOS mRNA isoforms expression in the left ventricular myocardium homogenates was carried out using a real-time polymerase chain reactionResults. In the experiment, an increase in all 3 isoforms and their mRNA was obtained. In the study, a decrease in nitrites concentration and a significant increase in nitrotyrosine levels, indicates the development of nitroso-oxidative stress.Conclusions. The development of experimental endocrine-salt hypertension in the Wistar rats leads to a stable increase in mean blood pressure by 65 % compared to control. Endocrine-salt arterial hypertension in Wistar rats is characterized by an increased mRNA content of all three isoforms of nNOS, eNOS and iNOS by 2.7, 2.8 and 5.7 times, respectively, compared to the control; increased expression of immunoreactive material to isoforms in transverse fibers by 14.3 %, 16.2 % and 18.5 %, respectively; in longitudinal fibers IRM to nNOS was higher by 8.3 %, to iNOS - by 8. 5%, but to eNOS it was lower by 7.6 %. At the same time, nitrites level decreased by 11.7 % and nitrotyrosine concentration was significantly higher, exceeding the control value by 88.5 %.

Purpose. The aim of this study was to identify the signifi cance of myocardial viability indicators calculated based on cardiac magnetic resonance imaging (MRI) with delayed contrast, as predictors of the adverse course of postoperative period in the surgical treatment of patients with ischemic cardiomyopathy.Material and Methods. A total of 178 patients underwent surgical treatment for ischemic cardiomyopathy from March, 2013 to December, 2017. All patients underwent preoperative cardiac MRI scan with paramagnetic contrast.Results. The logistic regression analysis showed that the left ventricular volumetric indicators and the amount of residual viable myocardium, calculated using delayed contrast-enhanced MRI, were the essential predictors of favorable and complicated course of postoperative period in ischemic cardiomyopathy patients. In patients with a residual viable left ventricular myocardium amount over 64.5%, surgical ventricular reconstruction procedure may be performed with a low risk of early postoperative complications (OR 8.25, 95% CI 1.45-46.8, p = 0.017).Conclusion. Cardiac MRI with delayed paramagnetic contrasting is a valuable method contributing to the preoperative identifi cation of a cohort of ischemic cardiomyopathy patients who can benefi t the most from surgical left ventricular reconstruction.

The left main coronary artery (LMCA) supplies majority of the left ventricular myocardium and atherosclerotic obstruction is associated with significant myocardial jeopardy. Coronary artery bypass surgery (CABG) has been the gold standard for LMCA disease in the past. The LMCA has special characteristics anatomically, poses different challenges with regard to percutaneous coronary intervention (PCI), and is often associated with multivessel disease. However, advancements in technology have established PCI to be a standard, safe, and reasonable alternative to CABG with comparable outcomes. Contemporary PCI of LMCA disease includes proper selection of the patients and correct technique, and is aided by intravascular ultrasound, optical coherence tomography, and physiological assessment with fractional flow reserve. In this review article, we discuss the anatomy, plaque characteristics of LMCA, current evidence from registries and randomized trials comparing with CABG, technical aspects of stent implantation, adjuvant technologies, mechanical circulatory supports, and triumph of PCI.

Adrenaline damage to the myocardium is an important element in the pathogenesis of myocardial infarction in humans. Despite the use of modern methods of treatment of myocardial infarction, the issue of cardioprotection of reperfusion myocardial damage remains open. Promising in this direction is the use of quinazolone derivatives, which have already shown cardioprotective properties in other models of myocardial infarction. The aim of the study was to establish morphological changes in the conditions of adrenaline myocardiodystrophy (AMD) against the background of the introduction of the compound PC-66 and amiodarone in rats. The study was performed on 100 nonlinear rats of both sexes weighing 165-220 g, divided into four groups of 25 animals each: 1 – intact rats; 2 – rats with a model of adrenaline myocardial infarction without treatment (control); 3 – rats with AMD treated with amiodarone (10 mg/kg, intraperitoneally); 4 – rats with AMD treated with compound PC-66 (10 mg/kg, intraperitoneally). It was found that control rats under conditions of cardiotoxic dose of adrenaline in the left ventricular myocardium for up to 8 days of the experiment does not fully restore the myocardial structure, dystrophic and necrobiotic changes were found in both cardiomyocytes and walls of vessels of a blood microcirculatory channel of a myocardium. Course intraperitoneal administration to rats of the compound PC-66 in the conditions of adrenaline myocardial infarction as well as amiodarone, contributes to the attenuation of signs of dystrophic and destructive processes. The degree of protective effect on the myocardium under conditions of cardiotoxic dose of adrenaline compound PC-66 was not lower to the reference drug – amiodarone. Thus, it is morphologically confirmed that in adrenaline myocardial infarction the compound PC-66, similar to the action of amiodarone, has a cardioprotective effect.

Objective To evaluate the accuracy of a deep learning-based automated segmentation of the left ventricle (LV) myocardium using cardiac CT. Materials and methods To develop a fully automated algorithm, 100 subjects with coronary artery disease were randomly selected as a development set (50 training / 20 validation / 30 internal test). An experienced cardiac radiologist generated the manual segmentation of the development set. The trained model was evaluated using 1000 validation set generated by an experienced technician. Visual assessment was performed to compare the manual and automatic segmentations. In a quantitative analysis, sensitivity and specificity were calculated according to the number of pixels where two three-dimensional masks of the manual and deep learning segmentations overlapped. Similarity indices, such as the Dice similarity coefficient (DSC), were used to evaluate the margin of each segmented masks. Results The sensitivity and specificity of automated segmentation for each segment (1-16 segments) were high (85.5-100.0%). The DSC was 88.3 ± 6.2%. Among randomly selected 100 cases, all manual segmentation and deep learning masks for visual analysis were classified as very accurate to mostly accurate and there were no inaccurate cases (manual vs. deep learning: very accurate, 31 vs. 53; accurate, 64 vs. 39; mostly accurate, 15 vs. 8). The number of very accurate cases for deep learning masks was greater than that for manually segmented masks. Conclusion We present deep learning-based automatic segmentation of the LV myocardium and the results are comparable to manual segmentation data with high sensitivity, specificity, and high similarity scores.

To date, it has been established that in the progression of coronary artery disease (CAD) and its complications, an increase in the level of homocysteine and hypovitaminosis D are essential. However, medical publications do not adequately cover the study of the effects of hyperhomocysteinemia and vitamin D deficiency on the course of atherosclerosis and the functional state of the myocardium, and requires more detailed research of this problem. Objective. To study the functional state of the myocardium depending on the degree of hyperhomocysteinemia and hypovitaminosis D in patients with CAD. Materials and methods. The study analyzed data from 69 diagnosed with CAD. Depending on the degree of hyperhomocysteinemia and the level of vitamin D, patients were divided into 3 groups. Results. In all patients, speckle-tracking echocardiography revealed a decrease in longitudinal and circular myocardial deformation. Patients with hyperhomocysteinemia and vitamin D deficiency had significantly lower myocardial deformity. Comparing the data of echocardiography, it was found that in patients of all three groups – no significant difference in hemodynamic parameters was found, despite the difference in the level of HC and vitamin D. Conclusions. Hyperhomocysteinemia and hypovitaminosis D are risk factors for the development of CAD. It was revealed that the higher level of homocysteine and the pronounced deficiency of vitamin D, are associated with more pronounced changes in the functional state of the myocardium.

The accurate 3D left ventricular (LV) myocardium segmentation in short-axis (SAX) view of cardiac magnetic resonance (CMR) is challenged by the sparse spatial structure of CMR. The strategy of multi-view CMR fusion can provide fine-grained spatial structure for accurate segmentation. However, the large information misalignment & lack of dense 3D CMR as fusion target in multi-view CMR fusion, and the different spatial resolution between the fused cardiac model and the ground truth of segmentation in segmentation limit the strategy. In this study, we propose a multi-view spatial-aware adversarial network (MVSGAN). It studies the perception of fine-grained cardiac structure for accurate segmentation by the spatially consistent fusion of multi-view CMR. It consists of three modules: (1) A residual adversarial fusion (RAF) module takes inter-slices deep correlation and anatomical prior of multi-view CMR to refine the spatial structures by residual supplement and adversarial optimization. (2) A structural perception-aggregation (SPA) module establishes the spatial correlation between the spatially dense cardiac model and sparse segmentation label for accurate 3D CMR LV myocardium segmentation. (3) A joint training strategy utilizes the spatial dense SAX volume as explicit and implicit goals to jointly optimize the framework. The experiments are applied on a public dataset and a clinical dataset to evaluate the performance of MVSGAN. The average Dice and Jaccard score of LV myocardium segmentation obtained by MVSGAN are highest among seven existing state-of-the-art methods, which are up to 0.92 and 0.75. It is concluded that the spatial-aware multiview CMR fusion can provide meaningful spatial correlation for accurate 3D SAX LV myocardium segmentation.

Purpose To investigate the changes in deformation and myocardial microcirculation perfusion of left ventricular three-layer myocardium in patients with dilated cardiomyopathy (DCM) by using speckle tracking imaging (STI) and myocardial contrast echocardiography (MCE). Methods Twenty-four patients with DCM and 19 healthy controls were selected. Two-dimensional and MCE dynamic images of apical four-chamber, two-chamber, and three-chamber sections and left ventricular mitral valve, papillary muscle and apex sections were collected. The peak values of longitudinal strain (LS), circumferential strain (CS), cross-sectional area of a microvessel (A) and average myocardial microvascular lesion (β) were obtained by Qlab 10.8 workstation values, and myocardial blood flow (MBF) was calculated with A × β to evaluate the deformation and coronary microvascular perfusion of left ventricular three-layer myocardium. Results The brain natriuretic peptide (BNP), left ventricular mass index (LVMI), left ventricular end-diastolic diameter (LVEDD), left ventricular end-systolic diameter (LVEDS), left ventricular end-diastolic volume (LVEDV), left ventricular end-systolic volume (LVESV), left atrial volume index (LAVI), E peak in early diastolic period/A peak velocity in late diastolic period (E/A) and average E/e' in the DCM group were higher than those in the control group (P P P middle > subepicardial. The correlation coefficients of LS with A, β, and A × β were − 0.500, -0.279 and − 0.190, respectively, and the correlation coefficients of CS with A, β, and A × β were − 0.383, -0.255 and − 0.208, respectively. Conclusions The deformation of the three-layer myocardium and coronary microcirculation perfusion in DCM patients were diffusely damaged from the endocardium to the epicardium, layer by layer. The longitudinal function of the left ventricular myocardium was closely related to changes in myocardial microcirculation perfusion. Echocardiography is helpful to evaluate myocardial blood flow and myocardial ischemia in patients with DCM.

Isolated left ventricular noncompaction, where broad trabeculae and deep intertrabecular recesses are observed in the left ventricular myocardium resulting from an arrest in normal embryogenesis, is a rare cardiomyopathy. We present a report on isolated trabeculectomy and postoperative echocardiographic follow-up showing recovery of cardiac function for isolated left ventricular noncompaction.

The article analyzes clinical guidelines oftheAmericanAcademy ofPediatrics dd 2017 “ClinicalPractice Guideline forScreening andManagement of High Blood Pressure in Children and Adolescents”. This document contains new values of blood pressure in children, replaces the term “prehypertension” with the term “elevated blood pressure”, provides a simplified classification of arterial hypertension in adolescents over 13 years and revisesthe guidelinesfor daily blood pressure monitoring and echocardiography. The documentspecifiesthe criteria for diagnosing increased body weight of the left ventricular myocardium, changesthe target blood pressure levels. This new guidelines helps to optimize the diagnostics and treatment of hypertension in children. At the same time there is need for further comprehensive analysis of clinicalrecommendations and assessment of their practicalsignificance for pediatrics.

The characterization of tissue-specific gene expression in failing hearts requires the identification of appropriately validated reference genes. This study sought to validate which commonly used reference genes were the most suitable for qRT-PCR data normalization in epicardial adipose tissue and left ventricular myocardium in patients with end-stage heart failure. The mRNA expression of 10 candidate reference genes was analyzed by qRT-PCR. The stability of their expression was evaluated by our novel scoring system and compared with known algorithms used to identify stable reference genes (Normfinder and Bestkeeper). Using these three methods, we selected the Ribosomal protein L13A (RPL13A) as the best reference gene when studying either epicardial adipose tissue or left ventricular myocardium in failing hearts. In contrast, the β2-microglobulin (B2M) gene was identified as a more suitable reference gene in studies comparing gene expression in epicardial adipose tissue to left ventricular myocardium.

The aim of this study is to create an automatic framework for sustained ventricular arrhythmia (VA) prediction using cardiac computed tomography (CT) images. We built an image processing pipeline and a deep learning network to explore the relation between post-infarct left ventricular myocardium thickness and previous occurrence of VA. Our pipeline generated a 2D myocardium thickness map (TM) from the 3D imaging input. Our network consisted of a conditional variational autoencoder (CVAE) and a classifier model. The CVAE was used to compress the TM into a low dimensional latent space, then the classifier utilised the latent variables to predict between healthy and VA patient. We studied the network on a large clinical database of 504 healthy and 182 VA patients. Using our method, we achieved a mean classification accuracy of \(75\% \pm 4\) on the testing dataset, compared to \(71\% \pm 4\) from the classification using the classical left ventricular ejection fraction (LVEF).

It is well established that the aging heart progressively remodels towards a senescent phenotype, but alterations of cellular microstructure and their differences to chronic heart failure (HF) associated remodeling remain ill-defined. Here, we show that the transverse tubular system (t-system) and proteins underlying excitation-contraction coupling in cardiomyocytes are characteristically remodeled with age. We shed light on mechanisms of this remodeling and identified similarities and differences to chronic HF. Using left ventricular myocardium from donors and HF patients with ages between 19 and 75 years, we established a library of 3D reconstructions of the t-system as well as ryanodine receptor (RyR) and junctophilin 2 (JPH2) clusters. Aging was characterized by t-system alterations and sarcolemmal dissociation of RyR clusters. This remodeling was less pronounced than in HF and accompanied by major alterations of JPH2 arrangement. Our study indicates that targeting sarcolemmal association of JPH2 might ameliorate age-associated deficiencies of heart function.

Aim of the paper was to address all strengths and weakness of cardiac magnetic resonance (CMR) in arrhythmogenic cardiomyopathy, trying to highlight areas where further research and investigations should be carried out to fill current gaps in scientific knowledge. Arrhythmogenic cardiomyopathy represents a multifaceted clinical entity associated with arrhythmias and sudden death. Even though different diagnostic tools are available for appropriate identification and risk stratification, over the last few years cardiac magnetic resonance (CMR) has surfaced as an unmatched non-invasive imaging tool. CMR is mandatory in the evaluation of arrhythmogenic cardiomyopathy. It is the only imaging technique providing the identification of myocardial fibrosis, particularly for left ventricular myocardium, as recent evidences demonstrated that left ventricular involvement in arrhythmogenic cardiomyopathy is associated with greater risk of sudden death than lone right ventricular involvement.

A long-standing problem at the frontier of biomechanical studies is to develop fast methods capable of estimating material properties from clinical data. In this paper, we have studied three surrogate models based on machine learning (ML) methods for fast parameter estimation of left ventricular (LV) myocardium. We use three ML methods named K-nearest neighbour (KNN), XGBoost and multi-layer perceptron (MLP) to emulate the relationships between pressure and volume strains during the diastolic filling. Firstly, to train the surrogate models, a forward finite-element simulator of LV diastolic filling is used. Then the training data are projected in a low-dimensional parametrized space. Next, three ML models are trained to learn the relationships of pressure–volume and pressure–strain. Finally, an inverse parameter estimation problem is formulated by using those trained surrogate models. Our results show that the three ML models can learn the relationships of pressure–volume and pressure–strain very well, and the parameter inference using the surrogate models can be carried out in minutes. Estimated parameters from both the XGBoost and MLP models have much less uncertainties compared with the KNN model. Our results further suggest that the XGBoost model is better for predicting the LV diastolic dynamics and estimating passive parameters than other two surrogate models. Further studies are warranted to investigate how XGBoost can be used for emulating cardiac pump function in a multi-physics and multi-scale framework.

In this introductory chapter to our book, in the hope of providing uniformity for the chapters which follow, we begin by discussing the reasons why we describe the valve guarding the left atrioventricular junction of the human heart as the mitral valve. We then outline our preferred terms for describing its components. These components together produce the mitral valvar complex, which intimately involves the left atrioventricular junction. Making up the complex are the so-called “annulus,” the valvar leaflets, their supporting tendinous cords, the papillary muscles, and the underlying left ventricular myocardium. We provide a brief review of the reasoning underscoring our preferred nomenclature, expanding on these issues in our chapter devoted to the anatomy of the different components.

BackgroundDuring left bundle branch (LBB) area pacing, it is important to confirm that the capture of the LBB is achieved, not just the capture of only the adjacent left ventricular myocardium (LV septal capture). Our aim was to establish ECG criteria for LBB capture by analyzing ECGs with confirmed LBB capture and non-capture. We hypothesized that since LBB pacing results in physiologic depolarization of the left ventricle then the native QRS can serve as a reference for the diagnosis of LBB capture in the same patient.MethodsOnly patients with direct evidence of LBB capture (output-dependent or refractoriness-dependent QRS morphology transition) were included. Several QRS characteristics were compared between the native rhythm and different types of LBB area capture. Receiver-operator characteristics analysis was performed to determine the optimal V6 R-wave peak time (RWPT) cut-off for LBB diagnosis.ResultsA total of 357 ECG tracing (124 patients) were analyzed: 118 with native rhythm, 124 with non-selective LBB capture, 69 with selective LBB capture and 46 with LV septal capture. Our hypotheses that during LBB capture the paced V6 RWPT (measured from QRS onset) equals the native V6 RWPT and that the paced V6 RWPT (measured from the stimulus) equals the LBB potential to V6 R-wave peak interval were positively validated. Criteria based on these rules had sensitivity and specificity of 98.0–88.2% and 85.7–95.4%, respectively. The optimal and 100% specific V6 RWPT values for differentiation between LBB capture and LV septal capture in patients with narrow QRS / right bundle branch block were 83 ms and 74 ms, respectively; while in patients with left bundle branch block/asystole/ventricular escape the optimal and 100% specific V6 RWPT values were 101 ms and 80 ms, respectively.ConclusionsNovel criteria for LBB capture were developed and optimal V6 RWPT cut-offs were determined.What this study addsWe showed that LBB pacing truly reproduce the physiological depolarization of the left ventricle since the paced V6 RWPT equals the native conduction V6 RWPT.Individualized LBB capture criteria, that use the native QRS as a reference, were developed.The optimal V6 RWPT values for differentiation between LBB capture and LV septal capture were determined, separately for patients with healthy and diseased LBB.

Introduction: 4D cardiac CT can reveal characteristics of arrhythmogenic right ventricular (RV) cardiomyopathy (ARVC) such as fat and fibrotic invasion into the RV and LV myocardium (RVM, LVM), an enlarged RV, reduced RV motion and bulging. Hypothesis: We could differentiate ARVC patients with fat and fibrotic invasion into the LVM from those without, using ECG, clinical, and other imaging characteristics. Methods: Retrospective analysis of 17 patients (11 males, 57±17 years) with suspected ARVC who underwent 4D cardiac CT. Results: 9 patients met the 2010 ARVC task force criteria. 4 had fat and fibrotic invasion into the LVM (group 1) but 5 did not (group 2). The remaining 8 did not fulfill the ARVC criteria (group 3). The proportion of males and age did not differ between groups. In groups 1, 2 and 3, respectively, 3 (75%), 4 (80%), and 1 (13%) patients had epsilon waves in V1-3 (group 1>3, P=0.033, group 2>3, P=0.005). 2 (50%), one (20%) and 4 (50%) had complete right bundle branch block (CRBBB) (all P=NS). Three (75%), 3 (60%), and 1 (13%) had inverted T waves in V1-3 or beyond (group 1>3, P=0.033). One (50%), 3 (75%), and 2 (50%) had terminal activation duration of QRS ≥55 ms measured from the nadir of the S wave to the end of the QRS, including R’, in V1, V2, or V3, in the absence of CRBBB (all P=NS). One (25%), 4 (80%) and 1 (13%) had sustained ventricular tachycardia (SVT; group 2>3, P=0.005). Two (50%), 1 (20%), and 3 (38%) had non-SVT (all P=NS). 4 (100%), 2 (40%), and 2 (25%) had clinical heart failure (group 1>2, P=0.019, group 1>3, P2, P=0.019, group 1>3, P3, P=0.002, group 2>3, P Conclusions: Most patients had RV enlargement on TTE and/or 4D CT. Presence of epsilon waves, reduced RV motion, and RV fat invasion on 4D CT may differentiate groups 1 and 2 from group 3, inverted T waves in V1-3 leads or beyond may differentiate group 1 from group 3, SVT may differentiate group 2 from group 3 but only clinical heart failure may differentiate groups 1 and 2.