The Correlation Between Abnormal Uterine Artery Flow in the First Trimester and Genetic Thrombophilic Alteration: A Prospective Case-Controlled Pilot Study

Introduction. Evaluation of the first trimester uterine artery flow can predict the development of obstetrical complications. A genotype, making women prone to microthrombi. constitutes the main known susceptibility factor for anomalous development of placenta. Our aim was to study whether polymorphisms of 10 genes leading to blood clotting abnormalities are related to abnormal uterine artery blood flow in the first trimester, and may predict placenta-related diseases. Material and methods. In primary analyses we included 19 singleton pregnancies with abnormal blood flow in the uterine arteries during the first trimester of gestation, and 24 matched control with normal flow patterns. All patients were genotyped for sequence variations in F5, F2, F11, MTHFR, SERPINE-1, CYP4V2, SELE, GP6, angiotensinogen (AGT) and fibrinogen gamma (FGG) genes and followed up until delivery. Results. There were no differences between groups regarding selected sequence variations in any of these genes. The co-occurrence of several polymorphisms in the same patient was also not related to the blood flow patterns in the uterine arteries. Conclusions. Although we found certain trends of genetic polymorphisms being related to preeclampsia and fetal growth, we failed to find an association between clotting gene polymorphisms, single or in combination, with the abnormal uterine flow in the first trimester.

Download Full-text

Preliminary Analysis of the Effects of Blood Vessel Movement on Blood Flow Patterns in the Coronary Arteries

Journal of Biomechanical Engineering ◽

10.1115/1.2895734 ◽

1994 ◽

Vol 116 (3) ◽

pp. 302-306 ◽

Cited By ~ 39

Author(s):

James E. Moore ◽

Nicolas Guggenheim ◽

Antonio Delfino ◽

Pierre-Andre´ Doriot ◽

Pierre-Andre´ Dorsaz ◽

...

Keyword(s):

Blood Flow ◽

Shear Rate ◽

Coronary Arteries ◽

Cardiac Cycle ◽

Flow Patterns ◽

Wall Shear Rate ◽

Axial Movement ◽

Wall Shear ◽

Artery Flow ◽

Blood Flow Patterns

Blood flow patterns are believed to be involved in the formation and progression of arterial diseases. It is possible that the normal physiologic movement of blood vessels during the cardiac cycle affects blood flow patterns significantly. For example, the contraction of the heart in systole and subsequent relaxation in diastole create movements of the coronary arteries, as evidenced in real-time angiography. The effects of this movement on coronary artery flow patterns have never been previously analyzed. This work was undertaken to provide a preliminary estimate of the importance of the effects of such physiologic movements on blood flow patterns in the coronary arteries. A Womersley-type solution was used to determine the effect of axial movement on the wall shear rate in a simplified model of the coronary arteries. The pulsatile pressure gradient was derived from previously published coronary artery flow waveforms. The axial movement function was obtained from a three-dimensional reconstruction of a biplanar coronary angiogram. Significant changes in wall shear rate were noted when the movement was taken into account. The maximum and minimum wall shear rates were 10 percent smaller and 107 percent larger in magnitude respectively, and the Oscillatory Shear Index (OSI) was doubled. Most of the changes in wall shear rate were observed in systole, when the pressure gradient is minimal and the movement is strongest. The results indicate that blood vessel movement during the cardiac cycle has a significant effect on hemodynamic phenomena which have been associated with the development of atherosclerosis.

Download Full-text

Ca2+-activated K+ channels modulate basal and E2β-induced rises in uterine blood flow in ovine pregnancy

AJP Heart and Circulatory Physiology ◽

10.1152/ajpheart.2001.281.1.h422 ◽

2001 ◽

Vol 281 (1) ◽

pp. H422-H431 ◽

Cited By ~ 39

Author(s):

Charles R. Rosenfeld ◽

David N. Cornfield ◽

Timothy Roy

Keyword(s):

Heart Rate ◽

Blood Flow ◽

Uterine Artery ◽

Late Pregnancy ◽

Uterine Blood Flow ◽

Calcium Dependent ◽

Uterine Arteries ◽

Near Term ◽

Artery Flow ◽

Oxide Synthase

Uterine blood flow (UBF) increases >30-fold during ovine pregnancy. During the last trimester, this reflects vasodilation, which may be due to placentally derived estrogens. In nonpregnant ewes, estradiol-17β (E2β) increases UBF >10-fold by activating nitric oxide synthase and large conductance calcium-dependent potassium channels (BKCa). To determine whether BKCa channels modulate basal and E2β-induced increases in UBF, studies were performed in near-term pregnant ewes with uterine artery flow probes and catheters for intra-arterial infusions of tetraethylammonium (TEA), a selective BKCa channel antagonist at <1 mM, in the absence or presence of E2β (1 μg/kg iv). Uterine arteries were collected to measure BKCa channel mRNA. TEA (0.15 mM) decreased basal UBF ( P < 0.0001) 40 ± 8% and 55 ± 7% ( n = 11) at 60 and 90 min, respectively, and increased resistance 175 ± 48% without affecting ( P > 0.1) mean arterial pressure (MAP), heart rate, or contralateral UBF. Systemic E2β increased UBF 30 ± 6% and heart rate 13 ± 1% ( P ≤ 0.0001, n = 13) without altering MAP. Local TEA (0.15 mM) inhibited E2β-induced increases in UBF without affecting increases in heart rate (10 ± 4%; P = 0.006). BKCa channel mRNA was present in uterine artery myocytes from pregnant and nonpregnant ewes. Exponential increases in ovine UBF in late pregnancy may reflect BKCa channel activation, which may be mediated by placentally derived estrogens.

Download Full-text