ABSTRACT
An anatomical-embryological correlation of anomalous venous pulmonary connection is presented to gain an insight of its pathogenesis. The basic publications on embryonic development of the pulmonary veins were analyzed in its two stages: the primary connection of these veins (collectors) with the embryonic systemic veins from which the definitive veins arise. These channels normally disappear once the pulmonary veins sinus is connected with the roof of the left atrium (secondary definitive connection); when the latter does not exist, any of the primitive channels persist and originates the anatomic sites of the anomalous venous pulmonary connection. The embryonic systemic veins are the right cardinal (superior vena cava and azygos vein), the left cardinal (venous coronary sinus and vertical vein) and the umbilical-vitelline (portal vein and ductus venosus). Other mechanisms are discussed such as ectopic origin of the primitive pulmonary vein in the roof of the right atrium and misplaced left of the atrial septum. The atrial septal defect is conditioned by the hemodynamics of this malformation. The knowledge of the pulmonary venous development is of great value in understanding the structure and the anatomic variants of this cardiovascular malformation in its total and partial forms.
Subject(s)
Humans , Abnormalities, Multiple/embryology , Heart Defects, Congenital/embryology , Pulmonary Veins/embryology , Pulmonary Veins/abnormalitiesABSTRACT
To know the morphological features and the frequency of pulmonary anomalous connection types, 106 hearts from the collection of the Instituto Nacional de Cardiologia Ignacio Chávez were studied with the segmental sequential system. The atrial situs, connections of cardiac segments, morphology of cardiac chambers, interatrial septum, venous collector, sites of anomalous pulmonary venous connection and associated anomalies were determined. Darling's classification was used. The atrial situs was: solitus (73), dextroisomerism (30) and inversus (3). In the supradiaphragmatic level the supracardiac connection (44) was distributed into superior vena cava (24) and vertical vein (20). The cardiac level (39) was divided into venous coronary sinus (22) and to the right atrium (17). The infradiaphragmatic level was to the portal vein (10) and the mixed group (13) had different combinations. 100 hearts had atrial septal defect and 6 had patent foramen ovale. The hearts with dextroisomerism had several intracardiac malformations; 14 specimens had obstructed venous collectors. Three important aspects in diagnosis are: site of anomalous connection, size of atrial septal defect and obstruction in the venous collector; this information is valuable to understand the physiopathology, to establish the diagnosis and to help the surgeon to chose the best surgical strategy.