Document Detail


The fetal aortic pressure pulse waveform in normal and compromised pregnancy.
MedLine Citation:
PMID:  9386025     Owner:  NLM     Status:  MEDLINE    
Abstract/OtherAbstract:
OBJECTIVE: To study the arterial pressure waveform in the descending thoracic aorta during pregnancy in both normal and compromised fetuses. DESIGN: The pressure pulsation waveform propagated along the vascular tree, and acting laterally on the arterial wall, produces a corresponding change in the vessel diameter. The distance between diametrically opposite points of the aortic lumen was followed using a phase locked loop echo tracking system coupled to a B-mode ultrasonic imager (central frequency 3.5 MHz). SETTING: Tertiary referral unit, teaching hospital. PARTICIPANTS: A cross-sectional study of 80 normal fetuses between 20 and 40 weeks yielded normal data. We studied 58 women with evidence of potential fetal compromise (high umbilical artery systolic: diastolic ratio). MAIN OUTCOME MEASURES: From the aortic diameter waveform we measured the maximum systolic and minimum diastolic dimension and calculated pulse amplitude. The first derivative of the aortic diameter waveform identified the incisura of aortic and pulmonary valve closure and was used to time the end of ventricular ejection and systole. RESULTS: In normal pregnancy there was an increase in systolic and diastolic diameter and pulse amplitude with advancing gestation. Ventricular ejection time was constant. In the fetal compromised group the absolute systolic and diastolic diameters were within the normal range, but diastolic diameter per unit fetal weight was increased. There was a decrease in pulse amplitude as a percentage of diastolic diameter and an increase in the diastolic systolic diameter ratio. Fetal outcome was examined in relation to the diastolic systolic diameter ratio. Those with a high ratio (above 90th centile of normal group) exhibited significantly more adverse indices of fetal outcome. CONCLUSIONS: The fetal aortic pressure pulse waveform was represented by the vessel diameter waveform. In fetal compromise reduced pulse amplitude and increased diastolic to systolic diameter ratio suggest corresponding changes in arterial pressure pulse. We suggest these are the response of the cardiac pump to increased afterload imposed by the high umbilical placental vascular resistance.
Authors:
A Mori; B Trudinger; R Mori; V Reed; Y Takeda
Related Documents :
1996435 - The effect of nifedipine on fetal umbilical artery doppler waveforms in pregnancies com...
3802445 - Detection and quantitation of constriction of the fetal ductus arteriosus by doppler ec...
2515015 - Effects of autonomic blockade on the hypertensive response of the fetus to hyperosmolal...
20855655 - Pregnancy downregulates actin polymerization and pressure-dependent myogenic tone in ov...
1498305 - The modified fontan procedure: physiology and anesthetic implications.
9609765 - Prostaglandin e2 and aggressive factors increase the gland luminal pressure in the rat ...
Publication Detail:
Type:  Journal Article    
Journal Detail:
Title:  British journal of obstetrics and gynaecology     Volume:  104     ISSN:  0306-5456     ISO Abbreviation:  Br J Obstet Gynaecol     Publication Date:  1997 Nov 
Date Detail:
Created Date:  1997-12-23     Completed Date:  1997-12-23     Revised Date:  2004-11-17    
Medline Journal Info:
Nlm Unique ID:  7503752     Medline TA:  Br J Obstet Gynaecol     Country:  ENGLAND    
Other Details:
Languages:  eng     Pagination:  1255-61     Citation Subset:  AIM; IM    
Affiliation:
Department of Obstetrics and Gynaecology, University of Sydney at Westmead Hospital, New South Wales, Australia.
Export Citation:
APA/MLA Format     Download EndNote     Download BibTex
MeSH Terms
Descriptor/Qualifier:
Aorta, Thoracic / embryology,  physiology*
Blood Pressure / physiology*
Cross-Sectional Studies
Female
Fetal Diseases / physiopathology*
Gestational Age
Humans
Placental Insufficiency / physiopathology*
Pregnancy
Ultrasonography, Prenatal

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine


Previous Document:  Hyperhomocysteinaemia and protein S deficiency in complicated pregnancies.
Next Document:  Antenatal corticosteroid prescribing: setting standards of care.