Search PubMed⌕ Search

Biomedical subjects

J C Huhta

Publications and source records attributed to J C Huhta.

At least 37 records · Page 2Linked to original sources
PubMed1996

Venous Doppler in the fetus with absent end-diastolic flow in the umbilical artery.

High perinatal mortality has been reported in association with the finding of absent end-diastolic flow velocities in the umbilical artery. The fetus is known to centralize its circulation during hypoxemia and abnormal venous blood flow velocities have been reported in cases of heart failure and imminent asphyxia. The aim of this study was to evaluate blood flow velocities recorded with Doppler ultrasound in the umbilical vein, inferior vena cava and middle cerebral artery as predictors of survival in 17 fetuses with absent or reversed end-diastolic flow in the umbilical artery. There were five perinatal deaths, all having abnormal umbilical cord venous pulsations. An increased proportion of diastolic blood flow velocity in the middle cerebral artery as a sign of hypoxia was found in 12 fetuses without a relationship to perinatal mortality. An increased proportion of retrograde blood flow in the inferior vena cava was recorded in only one fetus, which died on the same day of congestive heart failure, suggesting fetal heart sparing in the remaining complicated pregnancies. The results suggest that abnormal end-diastolic umbilical venous pulsation in the cord is a late and ominous sign of a severely compromised fetus, while abnormal blood flow velocimetry in the middle cerebral artery might be an earlier sign of fetal hypoxia, with a better prognosis.

Blood Flow Velocity↗
PubMed1996

Doppler echocardiography of normal and abnormal embryonic mouse heart.

To evaluate normal embryonic mouse heart development using Doppler echocardiography and to quantify changes in normal embryonic mouse cardiac function with increasing gestational age from the time of cardiac septation, a new method was applied using Doppler echocardiography. Trisomic embryos were screened to evaluate a model of abnormal cardiac anatomy. The development of the embryonic heart in mice has been well studied anatomically, but there are limited physiologic studies. A new method has been developed to assess the mouse fetal heart in a similar fashion to the current use of echocardiography in the chick embryo and the human fetus. This method was applied to normal mouse embryos known to survive and to abnormal trisomy embryos that die during gestation and have cardiac failure. To analyze early normal embryonic heart hemodynamics, Doppler echocardiograms were performed on n = 129 C57B1/6J mouse embryos from d 10 through 19 of gestation and 20 embryos with trisomy 16 (gestational d 11-14). The maximal blood velocities recorded at the inflow and outflow of the embryonic heart were analyzed for heart rate, peak early and peak late inflow and outflow velocities, and measurements were made of systolic ejection, filling, and other time intervals normalized for heart rate. A high velocity holosystolic or diastolic velocity with altered time intervals was identified as atrioventricular or semilunar valvular regurgitation, respectively. Inflow and outflow velocities increased with increasing gestational age. The time period of isovolemic contraction time was present before and undetectable after gestational d 17, whereas the total filling time increased. Ejection time and isovolemic relaxation time had no significant change. No valvular regurgitation was detected in normal embryos. These echocardiographic patterns are similar to those observed for human embryos. Abnormal Doppler findings were present (inflow or outflow valvular regurgitation) in 55% of trisomy 16 embryos. Echocardiographic data can now be obtained beginning at d 11 in the mouse embryo for analyses relating to abnormal heart development. A noninvasive technique may be invaluable to monitor the physiologic condition of embryos within a litter and to detect and monitor those embryos where heart defects may be expected. Qualitative markers of embryonic congestive heart failure such as valvular regurgitation may be present and detectable with structural valvular abnormalities or failing cardiac physiology. The mouse embryo is an appropriate animal model to analyze normal and abnormal mammalian heart development and function.

Animals↗
PubMed1995

Diagnosis and management of fetal cardiac tumors: a multicenter experience and review of published reports.

OBJECTIVES: We sought to determine the prevalence and natural history of cardiac tumors in patients referred for fetal echocardiography. BACKGROUND: Cardiac tumors are rare; the prevalence, reported from autopsy studies of patients of all ages, varies from 0.0017% to 0.28%. Despite many case reports, the prevalence and natural history of fetal cardiac tumors are unclear. METHODS: Fourteen thousand fetal echocardiograms recorded over an 8-year period in seven centers were available for retrospective review. Medical records and echocardiograms were studied to determine the reason for referral, family history of tuberous sclerosis, prenatal and postnatal course and tumor description and type. RESULTS: Cardiac tumors were present in 19 pregnancies (0.14%). Gestational age at diagnosis ranged from 21 to 38 weeks. The most common indication for referral was a mass on an obstetric ultrasound study. The tumors were singular in 10 patients and multiple in 9. Tumor size ranged from 0.4 x 0.4 to 3.5 x 4 cm, and the majority of tumors were not hemodynamically significant. There were 17 patients with rhabdomyomas, 1 with a fibroma and 1 with an atrial hemangioma. Tuberous sclerosis complex was diagnosed in 10 patients. Partial or complete tumor regression was seen in eight patients; tumors were unchanged in five; and three required operation. CONCLUSIONS: Fetal cardiac tumors, a rare condition, are often benign. The majority of tumors are rhabdomyomas, but not all fetuses with rhabdomyoma have tuberous sclerosis.

Female↗
PubMed1995

Late results of systemic atrioventricular valve replacement in corrected transposition.

From December 1964 to October 1993, 40 patients (aged 5 months to 70 years, mean 21.8 years, median 13.6 years) with corrected transposition and systemic atrioventricular valve insufficiency underwent replacement (n = 39) or repair (n = 1) of the systemic atrioventricular valve. Thirty-nine patients had situs solitus and 1 had situs inversus. Associated anomalies included Ebstein's malformation of the systemic atrioventricular valve (n = 22), ventricular septal defect (n = 19), and pulmonary stenosis (n = 14). Preoperatively, 16 patients (40.0%) had complete heart block and 27 patients (67.5%) were in New York Heart Association functional classes III and IV. The early mortality was 10.0% (n = 4) and 8 patients died subsequently. The principal cause of death in all 12 patients was systemic ventricular failure. Overall survival including early mortality was 78.0% at 5 years and 60.7% at 10 years; survival excluding early mortality was 86.7% at 5 years and 67.5% at 10 years. Survivorship correlated with preoperative systemic ventricular ejection fraction of 44% or more (p < 0.001) and later interval of operation (9 deaths in 15 patients before 1981 versus 3 deaths in 25 patients subsequently) (p = 0.06). There were no cases of surgically induced complete heart block. Two patients underwent late reoperations related to the systemic atrioventricular valve prosthesis. Follow-up extended to 26.0 years (median 4.7 years). At last follow-up, 18 of the 28 survivors were in New York Heart Association functional class I, 9 were in class II, and 1 was in class III. We conclude that the results of systemic atrioventricular valve replacement in corrected transposition have improved significantly during the past decade. To preserve systemic ventricular function, we suggest operation be considered at the earliest sign of progressive ventricular dysfunction as assessed by serial clinical evaluation and echocardiography.

Adolescent↗
PubMed1995

Fetal echocardiography during indomethacin treatment.

Fetal echocardiograms were evaluated in 315 studies performed in 107 fetuses exposed to indomethacin. In the majority of cases, the results of the fetal echocardiography study were within normal limits (74%). The most common abnormal phenomena were tricuspid valve regurgitation (10%), ductal constriction (6%), tricuspid valve regurgitation and ductal constriction (5%), an increased ductal velocity (2%), and other (3%). The difference between the prevalence of ductal constriction in the whole series of studies (11%) compared to the prevalence of ductal constriction per fetus (25%) (p < 0.001) suggests that this phenomenon was only temporary and disappeared when medication was discontinued. The mean gestational age for detection of tricuspid valve regurgitation was 27.7 +/- 2.8 weeks and for ductal constriction, 30.9 +/- 2.1 weeks (t-test, p < 0.01). Trivial tricuspid valve regurgitation was detected at a mean of 26.7 +/- 2.2 weeks and significant tricuspid valve regurgitation at 29.6 +/- 2.3 weeks (t-test, p < 0.01). We conclude that indomethacin treatment is relatively safe for the fetal heart. The most common side-effects are tricuspid valve regurgitation and ductal constriction. Tricuspid valve regurgitation may be detected before ductal constriction, but by itself it is not a contraindication for the continued use of indomethacin.

Arterial Occlusive Diseases↗
PubMed1994

Extracardiac anomalies, aneuploidy and growth retardation in 100 consecutive fetal congenital heart defects.

The importance of extracardiac anomalies in 100 consecutive fetuses with congenital heart disease was evaluated. The most common cardiac diagnoses were hypoplastic left heart syndrome in 35% and atrioventricular canal defect in 15%. Extracardiac anomalies were present in 42%, abnormal karyotype in 19% and intrauterine growth retardation in 20%. There were 45 survivors (35 required neonatal surgery, ten did not require early surgery) and 80% (36/45) of the survivors had isolated congenital heart disease. Extracardiac anomalies and abnormal karyotype were more frequently present in non-survivors (p < 0.001). Also, intrauterine growth retardation was more frequent in non-survivors (p < 0.05).

Journal Article↗
PubMed1994

Doppler in non-immune hydrops fetalis.

Fetal ultrasound studies were performed on 24 fetuses with non-immune hydrops to evaluate echocardiographic and cardiovascular Doppler parameters that may be useful in assessing hemodynamics and in predicting outcome. Of all cardiovascular parameters analyzed, only the presence of abnormal pulsations in the umbilical vein (p < 0.001) was found to be significantly different between the 11 survivors and 13 non-survivors. In a smaller subset of 12 fetuses, in whom inferior vena caval waveforms were recorded, survivors (n = 6) had a significantly lower percentage of retrograde flow in the inferior vena cava (p < 0.001) and higher inferior vena caval E/V velocity ratio (p < 0.001) than non-survivors (n = 6). Sixteen of the 24 cases examined had abnormal umbilical venous pulsations; 12 of the 16 (75%) died including all fetuses with hydrops due to twin-to-twin transfusion or congenital heart disease. When fetuses with pulsatile flow in the umbilical vein were compared with fetuses with normal umbilical venous flow, the following significant differences were found: lower right and left ventricular output velocities, larger inferior vena caval diameter, decreased shortening fractions of the right and left ventricles, and lower peak velocities at the aortic and pulmonary valves and in the ductus arteriosus.

Journal Article↗
PubMed1994

Diastolic function of the fetal heart during second and third trimester: a prospective longitudinal Doppler-echocardiographic study.

To generate normal charts of fetal cardiac inflow velocities and to assess physiologic changes of ventricular diastolic function, velocity waveforms of tricuspid and mitral valves were studied longitudinally in 49 fetuses in 4 week intervals from 14 weeks gestation to term. Doppler tracings were analyzed for: peak early (E) and peak late (A) inflow velocities, time velocity integral (TVI) of total inflow and A-wave velocity waveforms and heart rate corrected isovolemic relaxation time. E- and A-velocity as well as total- and A-wave-TVI of both valves increased significantly with gestational age (P < 0.001). Heart rate and A/E ratio decreased significantly with gestational age (P < 0.001). The ratio of A-wave TVI to total TVI of both valves and heart rate corrected isovolemic relaxation time (IVR) was constant suggesting unchanged diastolic function. This study provides normal charts for fetal cardiac inflow velocities. After 14 weeks of gestation all inflow velocities and their respective TVI's increased linearly in the growing fetal heart. There was evidence that diastolic function did not change. Area ratios and IVR should be used to determine changes in ventricular diastolic function, rather than velocity ratios.

Adult↗
PubMed1994

The prevalence and clinical significance of fetal tricuspid valve regurgitation with normal heart anatomy.

OBJECTIVE: Our purpose was to assess the prevalence, cause, and clinical significance of fetal tricuspid valve regurgitation in structurally normal hearts during indicated fetal echocardiographic examination. STUDY DESIGN: The prevalence of fetal tricuspid regurgitation was retrospectively evaluated in a group of 733 singleton fetuses referred for routine fetal echocardiography. RESULTS: The prevalence of this abnormality was 6.8%. Tricuspid valve regurgitation was most frequent in the group referred for fetal echocardiography to evaluate indomethacin exposure, followed by maternal diabetes. Factors associated with tricuspid valve regurgitation included ductal constriction, abnormal heart rhythm, atrial septal aneurysm, congestive heart failure, pericardial effusion, myocardial hypertrophy, and extracardiac malformations. Fetal tricuspid valve regurgitation was trivial in 80% (nonholosystolic, maximum velocity < 2 m/sec) and was significant in 20% (holosystolic, maximum velocity > 2 m/sec). Neonatal follow-up of tricuspid valve regurgitation was unremarkable. CONCLUSIONS: Fetal tricuspid valve regurgitation with normal heart anatomy was a frequent finding during indicated fetal echocardiographic examination and may indicate abnormal physiologic characteristics (increased preload or afterload, myocardial impairment, or arrhythmia). In the majority of cases (92%) the possible cause may be established. In other cases (8%) there may be "idiopathic" tricuspid valve regurgitation.

Echocardiography↗
PubMed1994

Pregnancy outcome following Mustard procedure for transposition of the great arteries: a report of five cases and review of the literature.

OBJECTIVE: To review outcomes and complications of pregnancies in women with transposition of the great arteries who had undergone the Mustard procedure. METHODS: Four women with transposition of the great arteries who had undergone Mustard procedures in childhood received their obstetric care for five pregnancies at three institutions in the greater Philadelphia area between 1990-1992. Pregnancy complications and outcomes were reviewed. RESULTS: The most common maternal complication in pregnancy following performance of the Mustard procedure was cardiac arrhythmia, which required treatment in two of four patients. Late-onset fetal growth restriction requiring induction occurred in two of five pregnancies. Third-trimester oligohydramnios requiring induction occurred in one patient, and her second pregnancy was complicated by preterm labor and premature rupture of the membranes (PROM) at 33 weeks. One patient with a twin pregnancy developed mild preeclampsia, preterm labor, and PROM at 30 weeks. There were no neonatal or perinatal deaths or significant morbidity. CONCLUSION: If a patient with transposition of the great arteries who underwent the Mustard procedure is hemodynamically stable before pregnancy, good maternal and fetal outcome can be expected.

Adolescent↗
PubMed1993

Sonographic differential diagnosis of fetal cardiac abnormalities.

Ultrasonographic evaluation of the fetal heart for structural and functional abnormalities is vital for prenatal diagnosis and perinatal management. Even more important than up-to-date diagnostic equipment is keen observation and an understanding of fetal cardiac abnormalities. One diagnostic approach begins with the four-chamber view with particular attention to the normal symmetric sizes of all four cardiac chambers. Ventricular disproportion, inequality in ventricular size, is often an easily detectable sign of a cardiovascular abnormality. Segmental diagnosis of cardiac and visceral situs, ventricular outflow tracts for conotruncal abnormalities and the aortic and ductal arches is also vital for diagnosing affected fetuses.

Diagnosis, Differential↗
PubMed1993

[Acute effects of cigarette smoking on fetal cardiovascular and uterine Doppler parameters].

The purpose of this study was to assess the effects of smoking one cigarette (nicotine mean 0.63 +/- 0.17 mg) on uterine- and foetal cardiovascular Doppler parameters in healthy pregnant smokers. All pregnancies (n = 16; mean gestational age: 36 +/- 4 weeks) had been uneventful and all foetuses were appropriate for gestational age with normal baseline Doppler parameters and normal foetal outcome (birthweight: 3254 +/- 340 grams). Measurements, performed immediately before and after smoking, included pulsatility index (PI) of umbilical artery (UA), middle cerebral artery (MCA), foetal descending aorta and uterine artery as well as maternal and foetal heart rate. The ratio of UA/MCA PI was used to assess centralisation. Changes in foetal cardiac output were determined by: time-velocity integral times heart rate, at aortic and pulmonary valve level. Foetal heart rate (p < 0.0005, paired t-test) and maternal heart rate (p < 0.05) increased significantly. All other parameters did not change significantly. However, in one additional woman with labile hypertension and increased baseline uterine artery PI (1.9), smoking of one cigarette caused a substantial rise in uterine artery PI to 3.25 ten minutes after smoking. Middle cerebral artery PI decreased from 2.2 to 1.18 with an unchanged cardiac output and umbilical artery PI raising the UA/MCA PI ratio from 0.51 to 0.81, suggesting a brain sparing effect. Smoking of one cigarette raised maternal and foetal heart rate. There was no evidence of other cardiovascular effects or centralisation in healthy foetuses of normal pregnancies, but this might not be true in foetus of pathologic pregnancies.

Adult↗
PubMed1992

2D echocardiographic assessment of the fetal heart size in the 2nd and 3rd trimester of uncomplicated pregnancy.

We report simple methods for assessing the fetal heart size by calculating the ratio of the area of the four chambers to the chest area when viewed in the same plane. The average value for this ratio in normal 99 fetal hearts was 0.30 +/- 0.05 and in 16 cases of fetal cardiomegaly it was 0.42 +/- 0.05. The difference was statistically significant (P less than 0.01). A second method is presented which involves measurements of the AP diameter of the heart in the longitudinal plane of the fetal trunk divided by the AP diameter of the chest just above the liver. The average value of this ratio in the normal group was 0.49 +/- 0.06. In a group with cardiomegaly, the average value was 0.62 +/- 0.04 and the difference was statistically significant (P less than 0.01). These methods to calculate heart size use only screen data, and are a simple tool to evaluate fetal heart cardiomegaly.

Adult↗
PubMed1991

Fetal hydronephrosis and renal artery blood velocity.

The renal artery blood velocity waveform was recorded by Doppler ultrasound in 17 fetuses with hydronephrosis in the third trimester of pregnancy. The waveform was analyzed for pulsatility index and related to the degree of dilatation of the renal pelvis. The pulsatility index was found to be above the renal reference range in only five out of the total of 31 kidneys examined. No relationship was found between the degree of dilatation and pulsatility index. A slight relationship was, however, found between abnormal pulsatility index and the need for operative intervention in the neonatal period. Doppler ultrasound is a valuable tool for evaluating renal circulation, but the results suggest limited clinical value in fetuses with hydronephrosis.

Journal Article↗
PubMed1991

Usefulness of color-flow Doppler in diagnosing and in differentiating supracristal ventricular septal defect from right ventricular outflow tract obstruction.

Color-flow Doppler is used for special localization of cardiac flows. The transeptal jet in supracristal ventricular septal defect (VSD) is directed toward the pulmonary valve and is often difficult to distinguish from the right ventricular (RV) outflow tract flow. Pulsed- and continuous-wave Doppler can misread the VSD jet as a stenotic lesion in the RV outflow tract. This study describes the color-flow Doppler characteristics of supracristal VSD and determines if color-flow Doppler can differentiate supracristal VSD jets from RV outflow tract flow. The study group comprised 28 patients ranging in age from 3 days to 23 years (mean 6.4), with catheter-diagnosed supracristal VSD in 14, isolated pulmonary valve stenosis in 10 and RV infundibular obstruction in 4. The echocardiographic Doppler and color-flow Doppler data of all patients were reviewed without knowledge of catheterization diagnosis. In all patients with supracristal VSD, color-flow Doppler revealed an abnormal transeptal jet directed toward the pulmonary valve that occurred 5 to 10 ms before RV outflow tract flow was identified. VSD and RV outflow tract jet could be differentiated by pulsed- and continuous-wave Doppler alone in 10 of 14 patients (71%). In 4 patients, differentiation was possible only with color-flow Doppler and electrocardiographic gating. Associated aortic regurgitation, or a fistula, or both, were detected in 6 patients. Pulsed- and continuous-wave Doppler with or without color-flow Doppler correctly identified the level of obstruction in all patients with RV outflow tract lesions (14 of 14). Supracristal VSD jet occurs in early systole and is directed toward the pulmonary valve.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗
PubMed1991

Acute fetal ductal occlusion in lambs.

To assess fetal right ventricular and hemodynamic responses to acute occlusion of the ductus arteriosus, the pulmonary pressure, right and left ventricular output, and right ventricular dimensions of five fetal lambs were measured with simultaneous echocardiographic monitoring. Ductal occlusion resulted in a rise in pulmonary arterial pressure, a decrease in right ventricular output of 68%, an increase in left ventricular output of 18%, and a fall in combined cardiac output of 34%. The right ventricular systolic dimension increased, and the shortening fraction decreased from 0.41 to 0.14. Tricuspid regurgitation started within two heartbeats after ductal occlusion and resolved as soon as the occlusion was released. Acute fetal ductal occlusion imposes a marked increase in the right ventricular afterload, resulting in reversible triscuspid regurgitation.

Animals↗
PubMed1991

Intrapartum course of fetuses with isolated hypoplastic left heart syndrome.

Once considered universally fatal, the hypoplastic left heart syndrome is now being surgically treated in the newborn period. To help formulate an appropriate management plan for the labor and delivery of these patients, we reviewed the intrapartum course and immediate neonatal outcome of 13 fetuses with known hypoplastic left heart syndrome. Eleven of 13 patients underwent labor, and only one had an abnormal fetal heart pattern. There were no cases with meconium staining of the amniotic fluid. All patients with spontaneous or induced labor were delivered vaginally. There were no Apgar scores less than 8 at 5 minutes, and all umbilical cord blood pH values were greater than or equal to 7.20. All infants survived to undergo initial reconstructive surgery. We conclude that labor does not appear to be a high-risk situation for the fetus with this disorder. Routine intrapartum fetal heart rate monitoring can be used, oxytocin can be used as indicated, and cesarean section should be reserved for traditional obstetric indications.

Female↗