1,720,984 research outputs found
Anatomical and pathophysiological classification of congenital heart disease
No full textCongenital heart diseases (CHD) consist of defects of the cardiac architecture which interfere with the venous drainage, septation of the cardiac segments and their sequences and regular function of the valve apparatuses. In the normal heart the segments are disposed in such a way to allow deoxygenated venous blood to go to the lungs through the pulmonary artery and the oxygenated venous blood to go to the systemic organs through the aorta without mixing. Small and great circulations are in sequence, with no communication to each other. Establishing the sequence of cardiac segments is the prerequisite for planning a surgical repair. We propose a pathyphysiological classification of CHD based upon the clinical consequence of structural defects on the physiology of blood circulation. We divided cardiac anomalies in: (1) CHD with increased pulmonary blood flow (septal defects without pulmonary obstruction and with left-to-right shunt); (2) CHD with decreased pulmonary flow (septal defects with pulmonary obstruction and with right-to-left shunt); (3) CHD with obstruction to blood progression and no septal defects (no shunt); (4) CHD so severe as to be incompatible with postnatal blood circulation; and (5) CHD silent until adult age
Juxtaposition of the atrial appendages.
No full textJuxtaposition of the atrial appendages is a rare congenital cardiac malformation, with the appendages both located on the left or right side of the great arteries. It is usually associated with cyanotic congenital heart disease. The aim of this report is to illustrate the anatomical features of normal and juxtaposed atrial appendages, with a review of the associated anomalies. In the Anatomical Collection of Congenital Heart Disease of the University of Padua, consisting in 1,526 specimens, we found 17 (1.1%) cases of atrial appendages juxtaposition with left juxtaposition in 15 (88%) and right juxtaposition in 2 (12%). Complete form was present in 11 cases and partial form in 6. In left juxtaposition, the situs was solitus in all, and the most frequent anomalies were complete transposition of great arteries in 9 (60%) and tricuspid atresia in 5 (33%); anomalies of position of the heart in the thorax (dextro-mesocardia) were present in 46% of cases, hypoplastic right ventricle in 73%, abnormal relation of the great arteries and subaortic or bilateral infundibulum in all. In right atrial juxtaposition, the atrial situs was solitus with mitral and pulmonary atresia in one case and left isomerism with aortic atresia and double-inlet right ventricle in the other. In describing this malformation, we propose to maintain the use of a positional definition using the terms right and left juxtaposition to describe the presence of both the appendages on the right or on the left side of the great arteries, respectively. The use of a morphological definition should be added in cases of situs inversus or isomerism, with description of the morphology of the appendage located in the wrong position
Bone-marrow derived CXCR4-positive tissue-committed stem cell recruitment in human right ventricular remodeling
No full textHum Pathol. 2010 Nov;41(11):1566-76.
Bone-marrow-derived CXCR4-positive tissue-committed stem cell recruitment in human right ventricular remodeling.
Castellani C, Padalino M, China P, Fedrigo M, Frescura C, Milanesi O, Stellin G, Thiene G, Angelini A.
Source
Department of Medical-Diagnostic Sciences and Special Therapies, University of Padua, Medical School, 35121 Padua, Italy.
Abstract
The epicardium contributes to cardiac formation, particularly during embryogenesis. It remains to be seen if it is also involved in postnatal myocardial homeostasis. This study evaluates the topographic distribution of stem cells (c-Kit) and extracardiac progenitor cells (CXCR4+) and their contribution to ventricular remodeling in a model of pressure volume overload leading to right ventricle hypertrophy. Eleven specimens with hypoplastic left heart syndrome were evaluated and compared with 6 normal hearts from subjects matched for age and weight. All underwent Norwood procedure with the right ventricle becoming a systemic one, with pressure and volume overload leading to right ventricle remodeling. Transmural cardiac tissue samples from the right ventricle were analyzed by immunohistochemistry and morphometry. This is the first study to demonstrate that c-Kit-positive progenitor cells and tissue-committed stem cells (CXCR4+/CD45-) are higher in children with systemic right ventricle remodeling. We also show that the localization of cardiac progenitor and recruited CXCR4+ stem cells in the myocardium is site specific in hearts with right ventricle hypertrophy. These cells are mainly scattered in the interstitium of the epicardial layer. In contrast, myocyte proliferation is not a key process in right ventricular hypertrophy. Induced by the overexpression of SDF-1α by the myocardium, CXCR4 cell mobilization resembles SDF-1 homing factor distribution, showing transmural enhanced expression from the endocardium toward the epicardium. The study provides evidences of the site-specific epicardial localization of stem cells in a model of pressure/volume overload and suggests that the epicardium acts as a permissive niche in normal and pathologic conditions.
Copyright © 2010 Elsevier Inc. All rights reserved.
PMID:
20621330
[PubMed - indexed for MEDLINE
CORONARY ARTERIAL-WALL AND ATHEROSCLEROSIS IN YOUTH (1-20 YEARS) - A HISTOLOGIC-STUDY IN A NORTHERN ITALIAN POPULATION
No full textSystemic-pulmonary arterial supply in pulmonary atresia with ventricular septal defect: postmortem angiograms and histologic survey.
No full textPostmortem angiographic and histologic studies of the pulmonary arterial circulation were performed in a patient with pulmonary atresia and a ventricular septal defect. While the left lung was supplied by a closing ductus arteriosus, the right lung was supplied by two systemic pulmonary arteries arising from the descending aorta. The examination disclosed that systemic pulmonary arteries lead into the pulmonary vascular bed and the capillaries of the alveolar walls. According to these observations, such collateral circulation is to be considered functional. The pulmonary vascular bed, supplied by the ductus arteriosus and the stenotic systemic pulmonary artery, showed a thin muscular layer in the small arteries and arterioles. On the contrary, medial hypertrophy and severe intimal proliferation were observed in the pulmonary segments perfused by the other large unobstructed systemic pulmonary artery, thus proving that asymmetric pulmonary vascular disease may complicate the natural history of this malformation
Histology of pulmonary arterial supply in pulmonary atresia with ventricular septal defect.
No full textA histologic study was performed on 22 specimens of pulmonary atresia with ventricular septal defect to 1) ascertain the existence of the main pulmonary artery; 2) distinguish the ductus arteriosus from the systemic collateral arteries (SCA); 3) establish the nutritive or functional nature of collateral circulation; and 4) evaluate the morphology of the distal pulmonary bed. Three cases had absent main pulmonary artery, one with and two without signs of infundibular septation. We suggest that absent main pulmonary artery may exist with both infundibular pulmonary atresia and persistent truncus arteriosus. SCAs have been found to have similar histological features as systemic muscular arteries of the same size--their medial muscular layer merges gradually into an elastic one at different depth inside the lungs. Injection of contrast material allowed us to demonstrate that these vessels are functional, since they inosculate into efficient pulmonary arteries ending in the respiratory units. When the distal pulmonary vascular bed is perfused by large SCAs, proliferative lesions like those found in large left-to-right shunts may occur. Early in infancy, banding of large, nonstenotic SCAs could protect the distal pulmonary vasculature. Moreover, total surgical repair should be associated with ligation of the SCA to avoid residual left-to-right shunt, if the pulmonary arteries can carry the full pulmonary blood flow
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