Normal Doppler parameters in pregnancy

Doppler ultrasound of fetal blood vessels in normal

  1. Doppler ultrasound uses sound waves to detect the movement of blood in vessels. It is used in pregnancy to study blood circulation in the baby, uterus and placenta. Using it in high-risk pregnancies, where there is concern about the baby's condition, shows benefits. However, its value as a screening tool in all pregnancies needs to be assessed.
  2. Intra- and interobserver reliabilities for the different Doppler parameters of the AoI were measured on 31 recordings covering all the gestational weeks in the study. We aimed for an optimum reliability of at least 0.75 and accepted a reliability of 0.4 as a criterion for moderate agreement 12, 13
  3. Doppler blood flow measurement from the uterine artery is used for prediction of preeclampsia, hypertensive disorders in pregnancy, and as complementary surveillance parameters in high-risk pregnancies and fetal growth restriction 1, 2. A reference curve from normal pregnancies is the basis for identification of pathological blood flow
  4. Umbilical Artery Doppler Reference Ranges. Umbilical Artery (UA) Impedance Indices are calculated by using ultrasound to measure the blood flow waveforms from the uterine arteries through a free-floating portion of the umbilical cord . The figure at the right shows the normal saw-tooth appearance of arterial blood flow through the umbilical cord

Reference ranges for Doppler parameters of the fetal

Doppler evaluation of uteroplacental arteries in normal gestation groups (I and II) (Tables 1 and 2). The results of the analysis revealed that the blood flow parameters viz. SPV, EDV, PI, and RI in group I and II did not differ significantly (p> 0.05) during 40 to 50 and 51 to 60 days of gestation.It indicates that in normal gestation body weight has no significant effect on blood flow. The Doppler indices have been found to decline gradually with gestational age (i.e. there is more diastolic flow as the fetus matures): S/D ratio mean value decreases with fetal age 8 at 20 weeks, the 50 th percentile for the S/D ratio is 4 at 30 weeks, the 50 th percentile is 2.8 UA Doppler indices normally decline (indicating decreased impedance) as pregnancy progresses. Because of the large surface area of the villous circulation, Doppler indices do not show increased impedance until at least 30% of the villous vasculature is abnormal

IUGR pregnancy with respect to normal and abnormal Doppler waveforms. Materials and methods Source of Data: The study was conducted at the Government General Hospital, Siddipet, from October 2016 to September 2018, in the Department of Obstetrics and Gynecology in pregnant women attending OPD, admitted i 15 Although the effects of normal ageing upon diastolic TDI parameters have been well-documented in the literature, the effect of age upon myocardial Sa velocity and consequently its normative reference values have been under-reported. The 5th percentile values for myocardial Sa velocity in this present cohort were 6, 6.7, and 6.8 cm/s for the. Fetal Doppler parameters represent a validated tool for testing fetal well-being at term and can select pregnancies that need increased surveillance. The aim of the present study was to evaluate the role of fetal Doppler parameters at term for the prediction of pregnancy outcomes in patients affected by GDM Umbilical artery Doppler • Umbilical artery Doppler is the most widely used Doppler examination in obstetrics and abnormal results have good correlation with adverse perinatal conditions. • Performed from 24 weeks gestation to term and it's purpose is to detect those fetuses at risk of perinatal morbidity or mortality due to growth. A fetal Doppler test normally takes place during your second trimester (weeks 13 to 28 of pregnancy). Some manufacturers of at-home fetal Dopplers say you may be able to hear your baby's heartbeat..

Uterine artery Doppler measurements during first and

Umbilical Artery Doppler Reference Range

These reference intervals showed how a normal pregnancy is expected to progress regarding these Doppler velocimetric parameters and are useful to follow high risk pregnancies. The comparison between results using different curves may provide insights about the best patterns to be used Doppler ultrasound provides a non-invasive method for the study of fetal hemodynamics. Investigation of the uterine and umbilical arteries gives information on the perfusion of the uteroplacental and fetoplacental circulations, respectively, while Doppler studies of selected fetal organs are valuable in detecting the hemodynamic rearrangements that occur in response to fetal hypoxemia

Sexual dimorphism in placental size and function has been described. Whether this influences the clinically important umbilical artery (UA) waveform remains controversial, although a few cross-sectional studies have shown sex differences in UA pulsatility index (PI). Therefore, we tested whether fetal sex influences the UA Doppler indices during the entire second half of pregnancy and aimed to. 15 Normal Fetomaternal Doppler Indices in the Second and Third Trimesters of Pregnancy. A. K. Ertan, H. J. Hendrik, I. Tossounidis, and W. Schmidt. Establishing Normal Curves. The goal of defining normal values for fetomaternal perfusion is to be able to discriminate between normal and abnormal pregnancies on the basis of Doppler ultrasound findings

cochinblogs: Pregnancy with fibroid and hypocoiled cord:

BACKGROUND: The aim of this study was to establish normative data for ophthalmic artery Doppler variables in the first trimester of normal pregnancy. METHODS: Maternal ophthalmic artery Doppler signals were recorded in 409 singleton pregnancies at 11-14 weeks' gestation, in mothers presenting consecutively for routine antenatal care Normal reference range of uterine artery Doppler in healthy singleton pregnancies from Northeast Brazil was established. The 95th percentile of UtA-PI and UtA-RI values may serve as a cut-off for future prediction of pregnancy complications studies (i.e., pre-eclampsia) in Northeast Brazil

Doppler US provides a unique window to the fetoplacental circulation, allowing assessment of fetal well-being. Doppler US of the umbilical artery is an integral component of managing the fetus with growth restriction; and Doppler US of the middle cerebral artery, as a noninvasive means of detecting fetal anemia, has revolutionized the management of pregnancies complicated by alloimmunization Doppler velocimetry Doppler velocimetry of the umbilical artery is a good tool for fetal assessment in FGR when the etiology is placental dysfunction related to progressive obliteration of the villus vasculature. Placental vascular changes lead to fetal hemodynamic changes that can be evaluated by umbilical artery Doppler A fetal Doppler test normally takes place during your second trimester (weeks 13 to 28 of pregnancy). Some manufacturers of at-home fetal Dopplers say you may be able to hear your baby's. The objective of the current study was to evaluate fetal arterial and venous Doppler parameters in postterm pregnancies with oligohydramnios and those with normal amniotic fluid

Doppler evaluation of maternal vessels in normal gestation

artery Doppler parameters associated with adverse pregnancy outcomes. Methods—A prospective cohort of women with singleton gestations between 11 and 14 weeks consented to uterine artery Doppler measurements. Doppler parameters were measured bilaterally, and mean pulsatility index (PI) and resistive index (RI) values were calculated #Women with an abnormal UA Doppler at 20-24 weeks (defined as a pulsatility index [PI] > 95th centile) and/or notching should be referred for serial ultrasound measurement of fetal size, AFI , BPP with umbilical artery Doppler commencing at 26-28 weeks of pregnancy. #Women with a normal uterine artery Doppler should be offered a single scan.

Doppler of Fetal heart Placenta location. BPP Parameters (Muscle tone, fetal movement, Breathing movements, and Amniotic fluid index) And possibly baby measurements if there is fundal height discrepancies. Tips for you this week. Surging hormones coupled with stress, anxiety etc. can affect any woman's emotional state during pregnancy DOPPLER SPECIFIC PARAMETERS Anatomy of a Waveform. Flow Time Corrected (FT c) Flow Time (FT) is the duration of time of the flow from the left ventricle during systole. Flow Time corrected (FTc) is Flow Time duration of blood flow in the aorta normalised to 60 beats/min using Bazett's equation. Typically FTc is one third of the cardiac cycle OBJECTIVE Objective of our study was to evaluate changes in Doppler resistance indices in the common hepatic artery during normal pregnancy. STUDY DESIGN Cross-sectional study included 210 healthy pregnant women gestational age 6-40 weeks, 40 healthy non-pregnant women and 30 women after delivery. We divided all pregnant women by pregnancy trimester Normal pregnancy, postpartum care and examination, encounter for contraceptive management, procreative management, outcome of delivery, and encounter for antenatal screening of mother: Middle cerebral artery Doppler velocimetry: CPT codes covered if selection criteria are met: 76821: Doppler velocimetry, fetal; middle cerebral arter Valores de referência para parâmetros doplervelocimétricos das artérias uterinas entre a 11 a e 14 a semanas de gestação em uma amostra populacional do Nordeste do Brasil; Translated title of the contribution: Reference range of uterine artery Doppler parameters between the 11 th and 14 th pregnancy weeks in a population sample from Northeast Brazi

Umbilical arterial Doppler assessment Radiology

  1. al pain should mandate at least a CTG trace, to.
  2. 1. Ultrasound Obstet Gynecol. 2009 Nov;34(5):605-7. doi: 10.1002/uog.7437. Severely abnormal flow patterns in the ductus venosus in the presence of otherwise normal fetal Doppler parameters in two cases of severe intrauterine growth restriction
  3. Throughout gestation, changes in foetal umbilical cord Doppler parameters in ewes were detected. Doppler ultrasonography of the umbilical artery was performed weekly starting at 18 weeks before parturition until birth
  4. No IUGR: Where the baby is constitutionally small but the doppler parameters are normal, pregnancy can be taken until 40 weeks. Labor may be induced at 40 weeks if the patient does not go into labor by 40 weeks and there are no contraindications for normal vaginal delivery. If the gestational age is less than 40 weeks, the mother is monitored.

The S/A ratio may throughout the normal pregnancy from 18 to 36 weeks. be consider abnormal when it is superior to 3.4. P232 P230 Blood flow velocity waveforms in fetal pulmonary arteries Doppler flow in the fetal circulation - III Objective: To evaluate the ductus venosus hemodynamic parameters in 31 - 40 weeks gestation normal fetus in the Paki- stani population using Doppler ultrasonography. Material and methods: In a. Performance of the Coupled LV-Arterial System in Normal Pregnancy. The basic hemodynamic parameters of heart rate, stroke volume, and cardiac output increased throughout gestation and peaked in the third trimester, and MAP did not change. These findings are similar to previously reported data 2009 208 12 -40 Normal PB, VI, Fl, VFI FGR Useful Tuuli 43 2010 120 11 -14 Normal VI, Fl, VFI Correlation of VI & VFI more indices± PB reliable than Fl in PB Hafner 21 2010 383 11 -14 Normal PV, PQ, VI, Fl, Pregnancy outcome Useful for IUGR Ute rine art. Doppler and PE Yigiter 4

Doppler Ultrasound Evaluation of the Fetus and Placenta

Doppler echocardiographic parameters in normal pregnant and healthy nonpregnant women The conventional and tissue Doppler parameters of the study participants are shown in Table 5 . There was a statistically significant increase in transmitral A wave velocity ( P < 0.05) but slight increase in E wave velocity resulting in a significant decrease. Our study is one of the few that has aimed to assess the effects of GDM on Doppler parameters of the fetal MCA and umbilical artery (UA) and to compare with normal pregnancies. This cross-sectional study was performed on 66 pregnant women, including 33 women with GDM and the others without it, in Akbar-Abadi University Hospital in Tehran, Iran. While Doppler ultrasound screening is beneficial for women with high-risk pregnancies, there is insufficient evidence on its benefits and harms in low- and unselected-risk pregnancies. This may be related to fewer events of abnormal Doppler flow, however the prevalence of absent or reversed end diastolic flow (AEDF or REDF) in such women is unknown

Normative reference values for the tissue Doppler imaging

  1. A total of 111 singleton normal pregnancies were studied during the second half of pregnancy using a combined color-coded Doppler and two-dimensional real-time ultrasound system
  2. Kurjak A, Kupesic S. Parallel Doppler assessment of yolk sac and intervillous circulation in normal pregnancy and missed abortion. Placenta 1998;19:619-623. Cepni I, Bese T, Ocal P, Budak E, Idil M, Aksu F. Significance of yolk sac measurements with vaginal sonography in the first trimester in the prediction of pregnancy outcome
  3. A high-risk pregnancy is a situation which puts the mother, the fetus, or both at greater risk than a normal pregnancy. The shear wave velocity (SWV) showed no significant difference between the placenta of normal pregnancies in the second and third trimesters (0.85 ± 0.43 m/s and 0.89 ± 0.57 m/s, respectively)
  4. e whether there is a relationship between abnormal umbilical artery Doppler studies (UADS) and small for gestational age (SGA) birth weight and other adverse perinatal outcomes in fetuses that appear normally grown by ultrasound. This was a retrospective study of all women who had UADS performed at or after 26 weeks of gestation at our institution between January 2005 and December 2012
  5. ultrasonographic parameters (mean gestational sac diameter, yolk sac diameter, crown rump length, embryonic heart rate and uterine artery Doppler) in predicting early pregnancy failure in patients with recurrent pregnancy loss
  6. Objectives Recently our group showed that first trimester maternal ophthalmic artery Doppler could be a predictor factor for early‐onset pre‐eclampsia. The aim of this study is to establish normative data of ophthalmic artery Doppler parameters in the first trimester of pregnancy. Methods Maternal ophthalmic artery Doppler were performed in 251 singleton pregnancies at 11-14 weeks of.

Fetal Doppler Parameters at Term in Pregnancies Affected

  1. growth restriction or abnormal Doppler parameters, and we calculated the sensitivity, specificity, positive predict-ive value (PPV), and negative predictive value (NPV). Results Table 1 shows the number and age of patients involved in the study. The study included 139 females (29.5%) with healthy pregnancy. The females with essentia
  2. When all other parameters are within normal limits, the need for an NST is questionable. Manning et al. described a high-risk pregnancy protocol where routine NST was not performed when all other BPP parameters were normal . Others view the NST and the BPP as independent predictors of normal outcome . The BPP is usually performed to lower the.
  3. e their renal volumes and right.
  4. ed in fetus prenatal detection with intrauterine growth restriction (IUGR) within Pregnancy Induced Hypertension (PIH) and their respiratory menace.A prospective analysis was performed in 141 third-trimester pregnancies
  5. Bower S, Vyas S, Campbell S, Nicolaides KH. Color Doppler imaging of the uterine artery in pregnancy: normal ranges of impedance to blood flow, mean velocity and volume of flow. Ultrasound Obstet Gynecol. 1992 Jul 1. 2(4):261-5. . Doubilet PM, Benson CB. Sonographic evaluation of intrauterine growth retardation
  6. Ectopic Pregnancy— Although it's rare, bleeding after sex during pregnancy can also be a sign of an ectopic pregnancy, which is when the fertilized egg attached outside of the uterus (meaning that the baby won't survive). Miscarriage— More on this in the section below

Fetal Doppler--Listening to Baby's Heartbea

  1. PURPOSE: To evaluate whether Doppler ultrasonographic (US) velocimetry in renal interlobar arteries is altered in women with pregnancy-induced hypertension (PIH) compared with that in healthy pregnant and nonpregnant women. MATERIALS AND METHODS: Flow waveform measurements in renal interlobar arteries were obtained in 39 nonpregnant women, 77 healthy pregnant women at 16-40 weeks gestation.
  2. ute period every month or every 2 weeks in case of pathological pregnancy
  3. Fetal Doppler Heart Rate UNDER Normal Range. Many times, a baby's heart rate is slightly under the normal heart rate range and they're still healthy. However, if you think your baby's heartbeat is lower than what it should be, contact your doctor or midwife. Heart rates slower than normal ranges may be caused by chromosomal abnormalities
  4. Cerebroplacental ratio. CPR: Z-score (SDs away from the expected normal mean for this gestation): (centile: ) Umbilical artery PI median. 5 th and 95 th centiles. 20 24 28 32 36 40 0 0.2 0.4 0.6 0.8 1 1.2 1.4 1.6 1.8 Gestational age (w) Middle cerebral artery PI median. 5 th and 95 th centiles
  5. If the results of Doppler US remain normal, delivery is recommended at 38-39 weeks. With decreased diastolic flow, antenatal testing (eg, nonstress tests, amniotic fluid measurement, and biophysical profile) is increased in frequency, Doppler US is performed weekly, and delivery is considered after 37 weeks
Normal 37 weeks pregnancy and ultrasound, your complete

The American College of Radiology will periodically define new practice parameters and technical standards for radiologic practice to help advance the and third trimesters of pregnancy, a more detailed fetal anatomic examination may be necessary in some biophysical profile and fetal Doppler ultrasound, or additional biometric. CONCLUSION: Normal reference range of uterine artery Doppler in healthy singleton pregnancies from Northeast Brazil was established. The 95th percentile of UtA-PI and UtA-RI values may serve as a cut-off for future prediction of pregnancy complications studies (i.e., pre-eclampsia) in Northeast Brazil A Doppler pregnancy test is done in the same way that a normal ultrasound scan is done. The pregnant woman will be asked to lie down on the examination platform, and her skirt/pants will be lowered to expose the baby bump. The sonographer then applies a water-based gel on the tummy. The function of the gel is to facilitate a secure contact of.

Normal Values in Pregnancy and Ultrasound Measurements. Henry L. Galan. Laura Goetzl. Invasive Cardiac Monitoring 1214. Noninvasive Cardiac Monitoring 1214. Arterial Blood Gas Values (Third Trimester) 1215. Pulmonary Function Tests 1215. Pulmonary Function Tests, Mean Values 1215. Peak Flows Stable Over Gestation 1215 Normal Vital Signs in Pregnancy. Activated partial thromboplastin time Alanine aminotransferase (ALT, SGPT) Albumin Aldosterone Alkaline phosphatase Alpha-1-antitrypsin Alpha-fetoprotein Amylase Angiotensin converting enzyme Anion gap Antithrombin III, functional Apolipoprotein A-1 Apolipoprotein B Aspartate aminotransferase (AST, SGOT. Normal twins may also show growth imbalance in the early stage, and growth imbalance occurring in the early pregnancy and mid-pregnancy may not prompt a frequent monitoring. For the assessment of growth discordance, the main clinical reference should be based on growth parameters, which were the most important parameters in growth assessment.

Turn the doppler on and slowly — really slowly — move it around until you can hear the heartbeat. The earlier it is in your pregnancy, the lower you'll likely have to go. Try below your. For anyone expecting, getting a fetal Doppler will make your pregnancy less worrisome. In addition, it is a great device to bond with your unborn baby, if you want to enjoy an intimate moment with your little one before the delivery get a Popamazing Professional Prenatal Fetal Doppler Fetal Medicin Abstract. The aim of the present study was to compare the Doppler parameters of the fetal ductus arteriosus (DA) measured in the traditional longitudinal ductal arch (LDA) view and the newly introduced three vessels and trachea (3VT) plane of the fetal upper mediastinum. The peak systolic velocity (PSV), end‑diastolic velocity (EDV), time‑averaged maximum velocity (TAMXV) and velocity. Echocardiographic and Doppler parameters used in grading pulmonary regurgitation severity; Parameter Mild Moderate Severe Pulmonic valve Normal Normal or abnormal Abnormal RV size Normal ∗: Normal or dilated Dilated Jet size by color Doppler § Thin (usually < 10 mm in length) with a narrow origin Intermediat

Comparison of Outcome of Normal and High-Risk Pregnancies

Practice Parameters AIUM practice parameters are intended to provide the medical ultrasound community with guidelines for the performance and recording of high-quality ultrasound examinations. The parameters reflect what the AIUM considers the minimum criteria for a complete examination in each area but are not intended to establish a legal. Worldwide preeclampsia (PE) is the leading cause of maternal death and affects 5 to 8% of pregnant women. PE is characterized by elevated blood pressure and proteinuria. Doppler Ultrasound (US) evaluation has been considered a useful method for prediction of PE; however, there is no complete data about the most frequently altered US parameters in the pathology Doppler is a good surveillance tool to judge and predict the turning point at which the decreased perfusion-adapted fetus decompensates and delivery is necessary. 2,30 In contrast, for LGA fetuses, with which the placenta is usually large as well, there is an increased blood flow present, and the wave curve is normal, such that the usual.

Figure 3 Normal triphasic Doppler waveform. Diagram shows the four waves in the normal spectral Doppler waveform. The A wave (blue), which is above the baseline, has a retrograde component of flow toward the liver. The S (red) and D (green) waves are below the baseline with flow antegrade toward the heart Doppler ultrasound can be used to find the heartbeat of a fetus or how fast blood is moving through a vein or artery. Fetus: The stage of human development beyond 8 completed weeks after fertilization. Multiple Pregnancy: A pregnancy where there are two or more fetuses. Oxygen: An element that we breathe in to sustain life

A Radiologist's Guide to the Performance and

grade 3 placenta at 33 week doppler scan. devikaupen 20/07/12. dear all, During my last check up I noticed my placenta grading was 3, although my gynae has not pointed this out and nor has she warned me on anything but as a first time mom to be I am worried. What I read on the internet it seems that placenta does not grade to 3 before 36 weeks. Kitabatake A, Inoue M, Asao M et.al. Non invasive evaluation of pulmonary hypertension by a pulsed doppler technique. Circulation 1983;68:302-309. Van de Mooren K, Barendregt LG, Wladimiroff J. Flow velocity waveforms in the human fetal ductus arteriosus during the normal second trimester of pregnancy Fetal Growth Chart. If there are concerns about your baby's growth in the third trimester of pregnancy, you may get scans to track size on a growth chart. See examples of head and abdominal circumference growth charts. Also see a doppler scan of blood flow through the placenta. If your doctor has any concerns about your baby's growth later in. Stuart B, Drumm J, FitzGerald DE, Duignan NM. Fetal blood velocity waveforms in normal pregnancy. Br J Obstet Gynaecol 1980; 87:780. Pourcelot, L. Applications clinique de 1'examen Doppler transcutane In: Pourcelot, L(Ed): Velocimetric Ultrasonore Doppler 1974; 34:213

Those same researchers reported that Doppler sonography was useful in predicting the outcome of patients with lupus nephritis: in a prospective series of 34 patients with various degrees of nephritis, an elevated RI value was shown to be a predictor of poor renal outcome, even in patients with normal baseline renal function normal and abnormal Doppler studies is shown in table II. Patients with abnormal Doppler were more likely to have C- section. Emergency C- section was done more in group II with abnormal Doppler 28.2% & 66% as compared to normal Doppler studies. High incidence of perinatal asphyxia (16%) in term of lo [9] Gupta U, Qureshi A, Samal S. Doppler velocimetry in normal and hypertensive pregnancy. Internet J Gynecol & Obstet 2008;11(2):123-6. [10] Urmila S, Beena B. Triple vessel wave pattern by Doppler studies in normal and high risk pregnancies and perinatal outcome. J Obstet Gynecol India 2010;60(4):312-6

Doppler parameters of the maternal hepatic artery blood

A Doppler ultrasound is an imaging test that uses sound waves to show blood moving through blood vessels. A regular ultrasound also uses sound waves to create images of structures inside the body, but it can't show blood flow. Doppler ultrasound works by measuring sound waves that are reflected from moving objects, such as red blood cells 3rd trimester ultrasound normal appearances, how to, scanning technique, protocol, charts, graphs, growth, doppler of umbilcal artery. GooGhywoiu9839t543j0s7543uw1. Please add analytics5@thewebshowroom.com.au to GA account UA-17294186-1 with Manage Users and Edit permissions - date Aug 10, 2017 Objectives. To assess the effects of routine fetal and umbilical Doppler ultrasound, or a combination of uterine Doppler ultrasound and umbilical Doppler ultrasound, in unselected and low‐risk pregnancies on obstetric practice and pregnancy. A low‐risk population is defined as a population where those considered at risk have been excluded

Normal 34 week pregnancy and ultrasound, your completeProfessional Ultrasound For Angel Sounds Fetal Doppler

Table 1: Normal and Abnormal Doppler Wise Distribution of Cases Doppler Number Percentage Normal 25 41.67 Abnormal 35 58.33 Total 60 100.00 After studying three arteries, patients were classified into normal and abnormal based on their color Doppler indices. Normal were those with no abnormality in any of the arteries At 30 weeks pregnant your baby is about the size of a head of cabbage. It weighs around 3 pounds (1.36 kg). Although your belly might make you feel like you have watermelon inside, the baby's height is around 15 inches (38 cm). As the baby grows, the amount of amniotic fluid will be reduced. This is a great sign of normal growth

US and power Doppler US are helpful diagnostic tools in the diagnosis of HT in anti-thyroid marker-positive patients with normal thyroid hormone levels. In addition to grayscale parameters, the use of power Doppler US and investigation of the presence of paratracheal lymph nodes increased the sensitivity and accuracy of US Doppler scan is a well-approved procedure used to analyze issues amid pregnancy. Doppler scan can monitor the blood flow in different parts of the infant's body. Regular blood flow in the baby's umbilical cord, brain, and heart shows that the baby is getting oxygen and nutrients he needs by means of the placenta tension in Pregnancy (ISSHP). A sample of 160 healthy pregnant women with normal blood pressure were selected as the control group. The GE Voluson E8 and E10 four-dimensional (4D) ultrasonic diagnostic instruments and the three-dimensional (3D) power Doppler in angio-quantitative mode were used to measure the hemodynamic parameters of the placenta Doppler Parameters of Prosthetic Aortic Valve Function Normal Suggests Stenosis Peak Velocity < 3 m/s > 4 m/s Mean Gradient < 20 mmhg > 35 mmhg Doppler Velocity Index >= 0.3 < 0.25 Effective Orifice area > 1.2 cm2 < 0.8 cm2 Contour of Jet Triangular Early Peaking Rounded Symmetrical contour Acceleration Time < 80 ms > 100 ms 3.2 24 0.18 150 m