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Z Geburtshilfe Neonatol 2002; 206(1): 1-8
DOI: 10.1055/s-2002-20943
Übersicht

© Georg Thieme Verlag Stuttgart · New York

Doppler-Sonographie des Ductus venosus: Messung, Evaluation und derzeitiger klinischer Stellenwert

Dopplersonography of the ductus venosus: assessment, evaluation and actual clinical importanceSt.  Ritter, H.  Jörn, W.  Rath
  • 1Frauenklinik für Gynäkologie und Geburtshilfe des Universitätsklinikums der Rheinisch-Westfälischen Technischen Hochschule (RWTH) Aachen
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Publication History

25. 1. 2001

9. 4. 2001

Publication Date:
08 March 2002 (online)

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Zusammenfassung

Der Ductus venosus (DV) verbindet die intraabdominale Umbilikalvene mit dem Infundibulum der V. cava inferior und entwickelt sich während der Schwangerschaft zu einem trompetenförmigen Gefäß mit einem isthmischen Eingang, durch welchen das Blut beschleunigt wird und via Foramen ovale direkt in den linken Vorhof gelangt, ohne sich mit sauerstoffarmem Blut vom rechten Vorhof zu vermischen. Am Tiermodell wird das Blutflussvolumen im DV und die dopplersonographisch aufgezeichnete Hüllkurve seiner Maximalgeschwindigkeiten maßgeblich durch den zentralen Venendruck und die Herzfrequenz gesteuert. Das dopplersonographisch ermittelte Flussgeschwindigkeitsprofil des DV ist zweigipflig: Der erste Gipfel repräsentiert die Maximalgeschwindigkeit während der ventrikulären Systole, der zweite die während der Diastole; die minimale Geschwindigkeit am Ende der Diastole und damit den Nadir der Hüllkurve markiert die Vorhofkontraktion. Die Bestimmung des Verhältnisses der Blutflussvolumina von DV zu Umbilikalvene spiegelt die Blutumverteilung wider, steigt bei hypoxämischen Ereignissen an und ist somit ein verlässlicherer Parameter für die Evaluierung von fetalem Distress als die ausschließliche Geschwindigkeitsmessung. Bei ausgeprägt retardierten Feten, Empfängerzwillingen bei FFTS (Feto-fetales Transfusionssyndrom) sowie tachyarrhythmieinduzierter Kardiomyopathie ist die Interpretation der Pulsatilität am DV ein geeignetes Verfahren zur fetalen Zustands- und Prognosebestimmung sowie zur Verlaufskontrolle; bei pathologischem Strömungsverhalten (Null- oder Negativfluss während der Vorhofkontraktion) ist in den meisten Fällen die vorzeitige Entbindung indiziert. Eine Senkung der perinatalen Morbidität und Mortalität konnte durch die Doppler-Messung des DV bisher nicht nachgewiesen werden. In der Frühschwangerschaft kann die Doppler-Flusskurvenanalyse am DV einerseits zur Detektion von Feten mit chromosomalen Aberrationen und andererseits zur Detektion von sowohl chromosomal euploiden als auch aneuploiden Feten mit Herzfehlern beitragen.

Abstract

The ductus venosus (DV) connects the intra-abdominal umbilical vein with the infundibulum of the IVC and develops during pregnancy to a trumpet-shaped structure with a narrow isthmus that accelerates the blood jet crossing the IVC directly to the left atrium via the foramen ovale avoiding mixing with deoxygenated blood from the right chamber. In animal studies, blood flow and dopplersonographically analyzed blood flow velocity waveforms mainly is controlled by heart rate and central venous pressure. The velocity waveform of the DV contains two peak components: the first indicates systolic velocity of the ventricle, the second peak diastolic velocity. A nadir is seen during atrial contraction. In animal studies, DV blood velocity in hypoxemia is influenced by central venous pressure and heart rate. The determination of the DV/UV ratio reflects the redistribution of blood flow, increases in hypoxemia and is therefore more reliable than blood velocity measurement for the detection and evaluation of fetal distress. In cases with severely growth-restricted fetuses, recipient twin in TTTS (twin-to-twin transfusion syndrome), tachyarrhythmia-induced cardiomyopathia and congenital heart disease, the measurement and interpretation of DV Doppler waveform pulsatility seems to be a useful tool that provides important information on the fetal condition and outcome. In cases of zero or reverse flow during atrial contraction in most cases the delivery of the fetus is indicated. An improvement of morbidity and mortality using Doppler sonography of the DV has not yet been proven. In cases of fetuses with or without chromosomal aberrations with major defects of the heart it can be used in addition to the standard screening methods of the first trimester of pregnancy for detection of heart failure.

Schlüsselwörter

Ductus venosus - fetale Doppler-Sonographie - Flusskurvenanalyse - Pränataldiagnostik

Key words

Ductus venosus - fetal Doppler - blood flow velocity waveform analysis - prenatal diagnosis

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Dr. med. Stefan Ritter

Frauenklinik für Gynäkologie und Geburtshilfe

des Universitätsklinikums der RWTH Aachen

Pauwelsstraße 30

52074 Aachen

Email: s.ritter@post.rwth-aachen.de