Persistent left superior vena cava

Congenital venous anomalies are relatively common and some have clinical implications. An example of persistent left superior vena cava was found during a routine dissection. This vein was carefully dissected and followed to its termination in the right atrium. The same cadaver also presented four branches from the arch of the aorta. A left superior vena cava occurs in early development but disappears later. The clinical significance of such a persistent left superior vena cava assumes importance during cardiac catheterization via the left subclavian vein.     

Diameter of the superior vena cava in the newborn: clinical applications in parenteral nutrition

Summary The authors measured the superior vena cava in the newborn by radiologic, anatomic and histologic methods and analysed the correlations between cross-sectional area and the biometric data. This method makes it possible to select the size of catheter for parenteral nutrition via the superior vena cava in relation to body-weight.

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Le calibre de la veine cave supérieure chez le nouveau-né

Résumé Les auteurs analysent sur 46 mesures de la veine cave supérieure chez le nouveau-né (mesures radiologiques, anatomiques et histologiques), les corrélations entre la section de la veine et les constantes biométriques de l'enfant. Cette méthode permet de prévoir la taille des cathéters centraux cave supérieur que l'on utilise en clinique, en fonction du poids de l'enfant.

     

Geometrical variations of the canine superior vena cava: Relationship between diameter,segment length and transmural venous pressure

The dimensional variations of the superior vena cava throughout the cardiac cycle were investigated by means of angiographic and ultrasonic techniques. Results obtained by both methods were largely in agreement. In frontal direction the diameter curve resembled the transmural pressure variations, the sagittal diameter curve was not related to the venous pressure variations during certain phases of the cardiac cycle and compressional and/or stretching forces exerted by respectively the distending aorta and/or pulmonary artery and the contracting heart may have been responsible. Also segment length variations occurred: during atrial contraction, ventricular systole and early diastole the vein elongated, indicating the varying longitudinal traction forces, possibly exerted by the rotational movement of the contracting heart. Assuming elliptical symmetry the vena caval cross-section could be reconstructed, and the cross-sectional area, perimeter and segmental volume could be calculated throughout the cardiac cycle. Despite the high venous distensibility, no extreme collapse of the vein was observed during the cardiac cycle at low transmural pressures.     

Human smooth muscle cells of the aorta and vena cava: Different sensitivity to the inhibition of proliferation by heparin in vitro

Summary In this comparative study of the antiproliferative effect of heparin (average mol. weight 16 kD) a different heparin sensitivity between cultivated smooth muscle cells derived from the media of the human aorta and the vena cava is observed.Heparin induces a partial proliferation inhibition of 54% in the aortic- and 17% in the vena cava-derived smooth muscle cells on day seven.The increase in cell volume suggests a selection of larger volume subpopulation of cells or an influence on the G₂-phase of the cell cycle.Heparin and heparin-like compounds may develop into future therapeutic drugs for the prevention of increased smooth muscsle cell proliferation after vessel wall injury.Supported by the Deutsche Forschungsgemeinschaft project Th 257/3-2Dedicated to Prof. Dr. Dr. H.G. Lasch for his 60th birthday (28.9.1985). Presented at the 32nd Int. Congress of the European Tissue Culture Society (ETCS); Milano/Italy, September 1984     

A comparison of the effect of bleeding site on haematological and plasma chemistry values of F344 rats: The inferior vena cava, abdominal aorta and orbital venous plexus

Of paramount importance to most toxicity studies in rats is the evaluation of haematological, coagulation and clinical chemistry parameters. In European and North American countries, the orbital venous plexus (OVP) is currently the most common route for obtaining blood, whereas in Japan the inferior vena cava (IVC) and abdominal aorta (AA) are the preferred routes. In order to compare clinical pathology parameters from the three bleeding sites, 11-week-old male F344 rats were anaesthetised by ether inhalation, and blood samples collected by IVC, AA or OVP for subsequent haematological, coagulation and plasma chemistry analysis. Collection methods utilised a plastic (5 ml) syringe and needle for IVC and AA, and glass capillary tubes (1.5 mm × 30 mm) for OVP. Ten haematology parameters, two coagulation and 22 plasma chemistry parameters were assayed, and the results compared between the three bleeding sites. The results showed there were no essential differences in the haematological or plasma chemistry values when blood was withdrawn from either the IVC or OVP. However, blood collected from the AA exhibited white cell counts of only 40%\2-60% of the values from the other two sites, and plasma glucose values showed slightly higher values. Other haematological, coagulation and plasma chemistry values showed no meaningful differences between the three bleeding sites, any differences being small and not considered to be biologically or clinically significant.Although some values may vary with the selection of bleeding site, careful and gentle sampling, avoiding stress and artefacts (e.g. tissue fluid) will minimise these differences. It is important therefore that clinical pathology assays during the course of a toxicity study should use the same sample site, preanalytical conditions and analytical methods.The results obtained in this study will be used as baseline data for haematology and clinical chemistry characteristics for the three bleeding sites in male F344 rats.