Search results for "Heart Ventricles"
showing 10 items of 162 documents
Analysis of Microstructure of the Cardiac Conduction System Based on Three-Dimensional Confocal Microscopy
2016
The specialised conducting tissues present in the ventricles are responsible for the fast distribution of the electrical impulse from the atrio-ventricular node to regions in the subendocardial myocardium. Characterisation of anatomical features of the specialised conducting tissues in the ventricles is highly challenging, in particular its most distal section, which is connected to the working myocardium via Purkinje-myocardial junctions. The goal of this work is to characterise the architecture of the distal section of the Purkinje network by differentiating Purkinje cells from surrounding tissue, performing a segmentation of Purkinje fibres at cellular scale, and mathematically describin…
Cardiac regenerative capacity is age- and disease-dependent in childhood heart disease
2018
Objective We sought to define the intrinsic stem cell capacity in pediatric heart lesions, and the effects of diagnosis and of age, in order to inform evidence-based use of potential autologous stem cell sources for regenerative medicine therapy. Methods Ventricular explants derived from patients with hypoplastic left heart syndrome (HLHS), tetralogy of Fallot (TF), dilated cardiomyopathy (DCM) and ventricular septal defect (VSD) were analyzed following standard in vitro culture conditions, which yielded cardiospheres (C-spheres), indicative of endogenous stem cell capacity. C-sphere counts generated per 5 mm3 tissue explant and the presence of cardiac progenitor cells were correlated to pa…
Genetic and Epigenetic Factors of Takotsubo Syndrome: A Systematic Review
2021
Takotsubo syndrome (TTS), recognized as stress’s cardiomyopathy, or as left ventricular apical balloon syndrome in recent years, is a rare pathology, described for the first time by Japanese researchers in 1990. TTS is characterized by an interindividual heterogeneity in onset and progression, and by strong predominance in postmenopausal women. The clear causes of these TTS features are uncertain, given the limited understanding of this intriguing syndrome until now. However, the increasing frequency of TTS cases in recent years, and particularly correlated to the SARS-CoV-2 pandemic, leads us to the imperative necessity both of a complete knowledge of TTS pathophysiology for identifying bi…
Angiotensin II dependent cardiac remodeling in the eel Anguilla anguilla involves the NOS/NO system
2017
Angiotensin II (AngII), the principal effector of the Renin-Angiotensin System (RAS), plays an important role in controlling mammalian cardiac morpho-functional remodelling. In the eel Anguilla anguilla, one month administration of AngII improves cardiac performance and influences the expression and localization of molecules which regulate cell growth. To deeper investigate the morpho-functional chronic influences of AngII on the eel heart and the molecular mechanisms involved, freshwater eels (A. anguilla) were intraperitoneally injected for 2 months with AngII (1 nmol g BW-1). Then the isolated hearts were subjected to morphological and western blotting analyses, and nitrite measurements.…
Cardiac Magnetic Resonance with Delayed Enhancement of the Right Ventricle in patients with Left Ventricle primary involvement: diagnosis and evaluat…
2020
: Cardiac Magnetic Resonance (CMR) allows an accurate Right Ventricle (RV) assessment that could be of great relevance in diseases causing inflammation or fibrosis. The aim of this study was to evaluate the concomitant involvement of the RV in patients with delayed enhancement (DE) of the Left Ventricle (LV-DE) using CMR. We retrospectively enrolled 95 (male n. 66; age 55±18years; BMI 26±5kg/m2) consecutive patients with LV-DE who underwent a CMR (Achieva 1.5 T, Philips) for different indications: post-ischemic dilated cardiopathy (PDM), hypertrophic cardiomyopathy (HCM), myocardial infarction (MI), myocarditis/pericarditis (MP) and congenital heart disease (CD). We assessed the presence an…
Double inlet left ventricular main chamber, subaortic small left sided right ventricle and interrupted aortic arch type A. What operation is indicate…
1987
A case of a 23 year old female patient who suffered from the complex congenital heart lesion of a double inlet left ventricular main chamber, subaortic small left sided right ventricle and interrupted aortic arch type A is reported. With equally high blood pressures, the perfusion in the upper half of the body was maintained through the ascending aorta while the lower half and the lungs were supplied through the pulmonary artery and a patent ductus arteriosus (PDA). Angiographically, the bulbo-ventricular foramen appeared to be nonrestrictive. However, distinct signs of muscular subaortic stenosis were detected. The hemodynamic status principally allowed surgical correction when this became…
Effect of obesity on left ventricular function studied by radionuclide angiocardiography
1991
Several studies have shown a significant association of obesity with cardiovascular morbidity and mortality. The present study was carried out to investigate central and systemic haemodynamics in overweight and moderate obese, but otherwise healthy subjects, and in a lean control group to determine whether obesity can influence left ventricular performance per se. In this study an attempt has been made to eliminate misleading factors, such as diabetes, lipid abnormalities and hypertension. A total of 67 subjects, 44 with overweight or moderate obesity and 23 lean healthy subjects, were included. Patients were divided into three groups according to BMI levels and Garrow's criteria as follows…
Vulnerability of the right ventricle to cathodal, anodal, and bipolar stimulation at double diastolic threshold strength
1984
The repetitive ventricular response (RVR) to three stimulation techniques (bipolar, cathodal and anodal) was investigated in 35 patients. 26 patients suffered from coronary heart disease and 9 patients from dilative cardiomyopathy. The stimulation study was performed at a ventricular driving rate of 120/min with one and two premature ventricular extrastimuli. We used rectangular impulses of 1.8 ms duration at duable diastolic threshold strength. RVR was scored as follows: 0: no RVR, 1: one nonstimulated RVR, 2: two nonstimulated RVR, 3: three nonstimulated RVR, 4: four to ten nonstimulated RVR, 5: more than ten nonstimulated RVR lasting less than 2 minutes, 6: sustained ventricular tachycar…
MR imaging of the heart in patients after myocardial infarction: effect of increasing intersection gap on measurements of left ventricular volume, ej…
1999
International audience; Abstract: PURPOSE: To determine the extent to which the number of planes imaged at magnetic resonance (MR) imaging could be reduced without modifying the volume and thickness of the left ventricle. MATERIALS AND METHODS: Sixty-one patients were examined after a myocardial infarction. The whole left ventricle was imaged by using 5-mm contiguous breath-hold cine MR short-axis sections with no gap (SA(ng)) (two-dimensional fast low-angle shot sequence, 9/4.8 [repetition time msec/echo time msec]). The effect of omitting in two (short-axis sections with 5-mm gap [SA(5mm)]) or two sections in three(short-axis sections with 10-mm gap [SA(10mm)]) was studied. RESULTS: In th…
Information transfer in QT-RR dynamics: Application to QT-correction
2018
ABSTRACTThe relation between the electrical properties of the heart and the beating rate is essential for the heart functioning. This relation is central when calculating the “corrected QT interval” — an important measure of the risk of potentially lethal arrhythmias. We use the transfer entropy method from information theory to quantitatively study the mutual dynamics of the ventricular action potential duration (the QT interval) and the length of the beat-to-beat (RR) interval. We show that for healthy individuals there is a strong asymmetry in the information transfer: the information flow from RR to QT dominates over the opposite flow (from QT to RR), i.e. QT depends on RR to a larger e…