PubMed Health⌕ Search

Biomedical subjects

K Marsál

Publications and source records attributed to K Marsál.

At least 37 records · Page 2Linked to original sources
PubMed2001

Ventriculovascular physiology of the growth-restricted fetus.

OBJECTIVES: To examine the mechanisms by which intrauterine growth restriction may influence later cardiovascular risk by comparing the ventriculovascular physiology of gestational age- and weight-matched growth-restricted and normal fetuses. DESIGN: A prospective longitudinal observational study of 20 normal fetuses studied from 20 weeks to term at monthly intervals was compared with a growth-restricted cohort examined in the interval between diagnosis and delivery. The last values before delivery of the growth-restricted cohort were compared with the normal cohort in two analyses matched for weight and for gestation. Arterial and venous vessel wall physiology and aortic pulse wave velocity were examined longitudinally in the thoracic descending aorta and inferior vena cava using an ultrasonic phase-locked echo-tracking system. Serial echocardiographic examinations were performed assessing structure, ventricular dimensions, function and Doppler flows. RESULTS: There was a linear increase in cardiac preload and relative pulse amplitude in the inferior vena cava with gestation. In normal fetuses, the aortic pulse wave velocity, maximum incremental and late decremental velocities increased with gestation whilst the relative pulse amplitude decreased reflecting falling distal impedance. In both age- and weight-matched analyses, the growth-restricted fetuses showed significantly reduced values reflecting the chronic fetal ventriculovascular responses to increased placental impedance. Pulse wave velocity increased with gestation and was significantly less in the growth-restricted cohort. CONCLUSIONS: Growth restriction is associated with abnormal ventriculovascular physiology that represents a successful adaptive response to raised placental impedance and reduction in wall stress as evidenced by the lower fetal pulse wave velocity in growth-restricted fetuses. However, whilst fetal adaptive mechanisms may aid survival they may result in cerebral and vascular abnormalities that prejudice later cardiovascular health.

Aorta, Thoracic↗
PubMed2000

Management of pregnancies with suspected intrauterine growth retardation in Sweden. Results of a questionnaire.

BACKGROUND: Diagnosis and management of intrauterine growth retardation during pregnancy remain a major challenge in obstetric care. The objective of this survey was to evaluate the routine clinical management of pregnancies with suspected intrauterine growth retardation at obstetric departments in Sweden. METHODS: In 1997, a questionnaire was sent to all 59 obstetric departments in Sweden. Forty-two departments, caring for 83% of all deliveries in Sweden, replied. Four major topics were addressed: definition and diagnosis of intrauterine growth retardation; magnitude of the problem; clinical management; use of Doppler ultrasound in clinical decision-making. RESULTS: Intrauterine growth retardation is diagnosed by a combination of serial fundal height measurements and ultrasonic fetal biometry at 40 departments, two departments perform routine fetal biometry at 32 weeks. The diagnosis is most often made at 32-36 gestational weeks. Five departments use 1.5 s.d. below the mean as cut-off point for diagnosis of small for gestational age fetuses; 35 departments use mean - 2 s.d. and two departments mean - 2.5 s.d. Intrauterine growth retardation is suspected in 1.6-6.3% pregnancies. About 19% of patients with suspected intrauterine growth retardation are hospitalized. On average, 63% of all small-for-gestational age babies are diagnosed prenatally. Thirty-nine out of 42 obstetric departments use formalized management protocols. All departments use cardiotocography, repeat ultrasound scans and Doppler ultrasound for antenatal surveillance. CONCLUSIONS: In Swedish obstetric units, the diagnostic procedures and methods of fetal surveillance in pregnancies suspected of intrauterine growth retardation are more or less uniform. Doppler examination of umbilical artery is used at all responding departments and is considered a valuable asset in clinical decision-making.

Cardiotocography↗
PubMed1999

Epidermal growth factor in maternal urine--a predictor of intrauterine growth restriction?

Epidermal growth factor (EGF), an angiogenic and mitogenic peptide, is known to be essential for normal fetal development in mice. Hypothetically, low maternal urine EGF levels might be associated with intrauterine growth restriction (IUGR) or pre-eclampsia (PE). We carried out a prospective study of 1009 consecutive women whose urine was sampled in early pregnancy (at a median of 13 weeks of gestation) between January and November 1993. Thirty women gave birth to IUGR babies and 24 developed PE. The study was designed as a nested case-control study with two matched controls for each case. EGF and human chorionic gonadotrophin (HCG) levels were measured and expressed in ng EGF/mg creatinine and IU HCG/mg creatinine. Logistic regression analysis was made with EGF or HCG levels as explanatory variables. Urinary EGF levels were significantly lower in the IUGR subgroup than in their controls, but no such difference was found between the PE subgroup and their controls. In the series as a whole, smokers were found to have lower EGF and HCG levels than non-smokers. In addition, correlation was found to exist between EGF and HCG levels (Spearman's rho 0.35; P<0.001). We conclude that a relative deficiency of EGF in early pregnancy might be one of the pathophysiological mechanisms of IUGR. However, the EGF level was an insufficiently discriminative variable to be of use for screening purposes.

Adult↗
PubMed1999

Heredity for hypertension influences intra-uterine growth and the relation between fetal growth and adult blood pressure.

OBJECTIVE: To study whether heredity for hypertension influences intra-uterine growth and the relationship between fetal growth and adult blood pressure. DESIGN: Five-year prospective follow-up study with retrospective collection of data on size at birth and gestational age from obstetric records. SETTING: Centre of preventive medicine in Malmo, Sweden. SUBJECTS: Thirty normotensive men with and 27 without heredity for hypertension were investigated in 1990, and the majority (n = 28 and n = 20, respectively) in 1995 also. MAIN OUTCOME MEASURES: Two measures of intra-uterine growth were compared between the groups and related to adult systolic blood pressure: the birth weight deviation from the expected birth weight based on ultrasonically derived intra-uterine growth curves, and the degree of thinness at birth (ponderal index = weight/length3). RESULTS: The birth weight deviation in men with heredity for hypertension differed significantly from that in men without such heredity (%) (-6.9+/-12.0 versus +7.3+/-18.4; P = 0.002). Ponderal index was somewhat lower in the men with than in those without heredity for hypertension, but the difference did not reach statistical significance (kg/m3) (25.9+/-2.6 versus 27.0+/-2.2; P = 0.08). In the group with heredity for hypertension, systolic blood pressure correlated inversely with ponderal index both in 1990 (r = -0.44; P = 0.01) and 1995 (r = -0.49; P = 0.009), and the 5-year increase in systolic blood pressure correlated inversely with the birth weight deviation (r = -0.38; P = 0.04). No such correlations were found in the group without heredity for hypertension. CONCLUSION: Our results suggest that genetic factors contributing to the development of hypertension may influence intra-uterine growth.

Adult↗
PubMed1999

Do pre-, early, and mid-pregnancy life events influence gestational length?

The aim of this study was to determine whether the frequency and quality of reported life events during the 6 months before pregnancy to mid-pregnancy influence gestational age at birth. Seventy nulliparous women were studied at 12 and 25 gestational weeks with a 64-item self-rated life event questionnaire developed for obstetric groups. Life events were categorised into eight psychosocial areas according to the diagnostic and statistic manual (DSM-III-R). The women rated each experienced event as strainful or not strainful. Gestational age was determined by ultrasound biometry before 20 gestational weeks. The number of life events during the following periods was recorded from 6 months before pregnancy to 12 gestational weeks, from 12 gestational weeks to 25 gestational weeks, from 6 months before pregnancy to 25 gestational weeks. No significant relationships were found between the number of reported life events and pregnancy duration. Life events in different psychosocial areas also did not influence gestational age at birth. A non-significant relationship (p = 0.06) was found between pregnancy duration and the number of strainful events reported from 6 months before pregnancy to 25 gestational weeks, shorter pregnancy duration being found in women reporting many strainful events. Our findings suggest that life events in general do not influence pregnancy duration. However, if they are perceived as strainful, pregnancy length tends to decrease.

Adult↗
PubMed1999

Moderate smoking during pregnancy is associated with a reduced risk of preeclampsia.

BACKGROUND: To investigate the effects of maternal smoking during pregnancy on the development of preeclampsia (PE). METHODS: The study comprised two populations with singleton pregnancies, one collected from 1990 to 1994 at the Malmö University Hospital (Malmö series, n=14,510) and the other from the National Birth Registry of Sweden 1993 (National series, n=113,211). Women with PE (n=281 and n=2,865, respectively) were compared to those without PE, delivered in 1993 (n=2,811 and n=110,346, respectively). The subgroups of women who had PE associated with preterm birth (n=58 and n=693, respectively) were compared with the same control groups in both series. RESULTS: Multiple logistic regression analysis showed that, in comparison with non-smokers, moderate smokers (1-9 cigarettes per day) were characterized by a lower incidence of PE (odds ratio (OR) 0.4; 95% confidence interval (CI) 0.22-0.60), and PE associated with preterm birth (OR 0.1; 95% CI 0.01-0.67). The corresponding figures in the validating National series were also significantly lower for moderate smokers (OR 0.6; 95% CI 0.5-0.7 and OR 0.6; 95% CI 0.5-0.8, respectively). CONCLUSION: Moderate smoking during pregnancy seems to protect against the development of PE and PE associated with preterm birth. Nicotine might be the agent responsible for this protective effect.

Adult↗
PubMed1998

Does the prenatal diagnosis of fetal urinary tract anomalies affect perinatal outcome?

A review of the literature is presented. Congenital renal and urinary tract anomalies are described, and the possible consequences of detecting them in utero are discussed. Prenatal detection of lethal anomalies affords the parents the option of terminating the pregnancy. If termination of pregnancy is not an acceptable option for the parents, the antenatal knowledge of lethal fetal anomaly helps the clinician to avoid unnecessary obstetric intervention, e.g., cesarean delivery for fetal distress. In certain cases of nonlethal renal and urinary tract anomalies, antenatal detection may influence both obstetric and postnatal management. It seems reasonable to anticipate that this might improve the prognosis of some children in terms of better preservation of kidney function. However, no scientific evidence is available to support such a statement. There are no randomized trials evaluating the outcome of congenital renal and urinary tract anomalies using different prenatal and postnatal diagnostic and therapeutic approaches. It is hoped that further research will lead to more rational antenatal and postnatal management protocols.

Female↗
PubMed1998

Reproducibility of ultrasonic fetal volume blood flow measurements.

The intraobserver reproducibility of ultrasonic volume blood flow measurements in the human fetus was evaluated in this study. A new approach, simultaneous measurement of the vessel diameter and the flow velocity with a pulsed-wave Doppler ultrasound synchronized with a real-time ultrasound phase-locked echo-tracking system, was used to estimate volume blood flow (VBF) in the fetal descending aorta. Measurements were performed in a longitudinal study on 20 normally grown fetuses. Intraobserver reproducibility of repeated estimations of mean blood flow velocities throughout gestation was very good, with high values of intraclass correlation coefficient (IntraCC 0.80-0.91) and low values of coefficient of variation (CV 4-11%). The IntraCC of repeated vessel diameter measurements throughout gestation was low (0.30-0.68), whereas the values of CV were acceptable (< 12%), with the exception of the period between 140 and 167 gestational days (CV > 12%). The lower reproducibility of vessel diameter measurement contributed directly to the relatively low reproducibility of VBF estimations overall (IntraCC 0.25-0.70; CV 17-28%), as these are calculated from a formula using both flow velocity and vessel diameter. Nevertheless, the synchronized approach gives absolute values of vessel diameter, flow velocity and VBF comparable with values reported in the human fetus previously. The new method provides, by taking the vessel wall pulsations into consideration and by measuring diameter and velocity simultaneously, a more complete information on fetal haemodynamics and fetal physiology.

Aorta, Thoracic↗
PubMed1998

Cerebral Doppler blood flow velocimetry and central hemodynamics in the ovine fetus during hypoxemia-acidemia.

The purpose of this study was to assess the effects of hypocapnic hypoxia, acidemia and the combination of hypoxia/acidemia on blood flow velocity variables in the fetal cerebral circulation. Chronically instrumented fetal sheep were used and the ewes were induced to breathe a hypoxic gas mixture for about 90 min. This caused an initial period of hypoxemia followed by a period of mixed hypoxemia/acidemia. When the ewe was reoxygenated, the fetus experienced a period of normoxic acidemia. The fetal cerebral circulation was assessed by recording Doppler blood flow velocity waveform variables in a cerebral vessel and the umbilical artery, using standard ultrasound equipment. External carotid artery blood flow was maintained during hypoxic and hypoxic/acidotic periods despite a fall in cardiac output. In the cerebral vessel, mean maximum velocity (time-averaged maximum velocity), minimum diastolic velocity and maximum systolic velocity manifested increases during hypoxic and hypoxic-acidotic periods, but pulsatility index did not change due to the effect of reduced heart rate on pulsatility index. Umbilical artery pulsatility index increased in the hypoxic and hypoxic-acidotic periods, despite unchanged mean maximum velocity, minimum diastolic velocity and maximum systolic velocity. With acute hemodynamic changes, the measurement of pulsatility index can yield misleading results. For clinical and experimental research on the fetal cerebral circulation, more attention should be paid to the individual Doppler variables, especially to the mean maximum velocity, than to the pulsatility index alone. Changes in mean maximum velocity recorded from the cerebral artery seem to reflect changes in the cerebral arterial flow.

Acidosis↗
PubMed1998

Factor V Q506 mutation (activated protein C resistance) associated with reduced intrapartum blood loss--a possible evolutionary selection mechanism.

OBJECTIVES: To ascertain whether relationship exists between the presence of APC resistance [a hypercoagulable state due to a mutation (R506Q) in the factor V gene] and the occurrence of pre-eclampsia (PE), intrauterine growth retardation (IUGR), and pregnancy bleeding complications. DESIGN: A retrospective study. SUBJECTS: A study group of 122 women with PE and/or IUGR during a recent pregnancy and a control group of 465 healthy pregnant women. RESULTS: A significantly reduced risk of intrapartum bleeding complications in the APC-resistant subgroup as compared to the non-APC-resistant subgroup was suggested by reduced intrapartum blood loss, and pre- and postpartum haemoglobin measurements. The prevalence of APC resistance in the PE and IUGR subgroups did not differ significantly from that in the control group. CONCLUSION: The remarkably high prevalence of the potentially harmful factor V gene mutation in the general population may be the result of an evolutionary selection mechanism conferring such survival advantages as reduction in the risk of intrapartum bleeding on carriers of the FV:Q506 allele.

Biological Evolution↗
PubMed1997

Middle cerebral artery velocimetry as a predictor of hypoxemia in fetuses with increased resistance to blood flow in the umbilical artery.

About half of all fetuses with increased resistance to blood flow, but with still detectable diastolic blood velocity in the umbilical artery (UA), show signs of imminent asphyxia during labour indicating a need for operative delivery. Fetal brain-sparing during hypoxia is characterized by an increase in diastolic and mean blood flow velocity in the middle cerebral artery (MCA). The aim of this study was to assess whether MCA blood velocity in pregnancies with increased resistance to blood flow in the feto-placental circulation could predict the development of fetal asphyxia during labour. Fifty pregnant women with signs of increased feto-placental vascular resistance between 31 and 42 weeks of gestation were studied serially by Doppler ultrasound and the last examination was correlated to perinatal outcome. The MCA pulsatility index (PI), cerebroplacental PI ratio and mean MCA blood velocity were calculated and correlated to fetal outcome. Fetal brain-sparing was defined as MCA PI < mean -2 S.D., cerebroplacental PI ratio < 1.08 and mean MCA blood velocity >mean + 2 S.D. No significant association was found between signs of fetal brain-sparing and the perinatal outcome. Among fetuses with signs of increased resistance to flow in the umbilical artery, velocimetry of the middle cerebral artery did not identify those that would not withstand the strain of labour.

Apgar Score↗
PubMed1997

Maternal anxiety in late pregnancy and fetal hemodynamics.

The aim of this study was to investigate if fetal circulation is affected by maternal anxiety. 37 nulliparous women were studied prospectively in the third trimester of pregnancy, with self-rate tests of anxiety (STAI). Doppler ultrasound examination of the umbilical artery and fetal middle cerebral artery was performed at 37-40 gestational weeks. The pulsatility index (PI) was calculated and corrected for heart rate. The women were divided into groups of increasing levels of anxiety. The fetuses of women with high trait anxiety scores had significantly higher PI values in the umbilical artery (p = 0.0056), significantly lower PI values in the fetal middle cerebral artery (p = 0.0029) and significantly lower cerebro-umbilical PI ratios (p = 0.0002), suggesting a change in blood distribution in favor of brain circulation in the fetuses. Maternal weight, weight-increase, height, age, marital status, smoking habits, drinking habits and socio-economic factors known to affect fetal well-being did not interfere with these findings. No significant differences in birth-weight, length and head circumference were found between infants born to mothers with higher trait anxiety levels compared to mothers with lower trait anxiety levels. Our results suggest that maternal stress, in terms of trait anxiety, influences fetal cerebral circulation.

Adolescent↗
PubMed1997

Association between a low umbilical artery pulsatility index and fetal distress in labor in very prolonged pregnancies.

OBJECTIVE: To investigate the association between fetal, umbilical and uterine circulatory changes and adverse perinatal findings in very prolonged pregnancies. STUDY DESIGN: 44 women proceeding to 43 completed weeks of gestation with the intention of a trial of vaginal delivery were studied prospectively with ultrasound Doppler velocimetry. An intensified fetal surveillance was routinely commenced at 42 weeks and only uncomplicated pregnancies were allowed to proceed. The endpoint perinatal measures were oligohydramnios, fetal meconium release, fetal distress in labor and birth asphyxia. Flow variables in different groups were compared with the Mann-Whitney U test, Student's unpaired t-test, Wilcoxon signed-rank matched-pairs test, Fisher's exact test and contingency table analysis, and a two-tailed P value <0.05 was considered statistically significant. RESULTS: The umbilical artery pulsatility index was significantly lower in cases of fetal meconium release (n=12) and fetal distress (n=7). The umbilical venous flow velocity was significantly lower in cases of meconium, and the fetal aortic volume flow significantly higher in cases of fetal distress. No significant flow changes were found in connection with oligohydramnios (n=5) and birth asphyxia (n=2). Uterine flow was not significantly affected in any group. CONCLUSIONS: In very prolonged pregnancies, fetal distress in labor was not associated with an increased placental vascular resistance. In contrast to previous reports, the umbilical artery pulsatility index was low in cases of fetal distress and meconium release. The etiology is unknown, but a subclinical fetal hypoxia might have triggered a vasodilation of placental vessels. Vasodilation at an unchanged volume flow could also explain the decrease of umbilical venous flow velocity. The increased aortic volume flow indicates an increase of cardiac output in fetuses later developing distress in labor.

Blood Flow Velocity↗