Absence of the ductus venosus

Absence of the ductus venosus is a rare vascular anomaly, but clinicians should be aware that it can be diagnosed antenatally and the prognosis is dependent on the type of associated malformation of the fetal vascular system. Antenatal detection of a single umbilical artery and unexplained cardiomegaly should prompt detailed examination of the umbilical and portal veins. Absent ductus venosus is associated with three main patterns of abnormal venous circulation, the worst prognosis being seen when the umbilical vein bypasses the liver and connects to the right atrium. Fetuses with absence of the ductus venosus are at risk of other congenital anomalies including facial clefts, hemivertebrae, cardiac, genitourinary, gastrointestinal anomalies; affected infants also have a poorer prognosis. In conclusion, fetuses with features suggestive of absence of ductus venosus require referral to a tertiary perinatal center.     

Clinical profile and management of PDA in neonates

Patent ductus arteriosus (PDA) is recognised more often with increasing survival of preterm babies. The pharmacological closure of ductus by indomethacin has changed the man-agement of PDA¹. Twenty neonates admitted over a period of 21 months to Neonatal Intensive Care Unit (NICU) of M.S. Ramaiah Medical College hospital, Bangalore, who were diagnosed to have PDA, were analyzed. The objectives of this retrospective analysis were to study the clinical profile, the efficacy of oral indomethacin and the outcome of PDA. 2–D and Doppler echocardiaography were used to confirm the clinically suspected PDA. These neonates were treated with 3 doses of oral indomethacin (0.2–0.25 mg/kg/dose 12 hourly) along with fluid restriction and oxygen. Echocardiography was repeated to demonstrate the closure of PDA. The incidence of PDA was 2.3% of total NICU admissions. Seventy percent of this cohort were < 32 weeks of gestation, 55% had birth weight of < 1500 gms. Seventy percent (14) neonates had onset of PDA after 48 hrs of life. 81.25% of neonates responded to indomethacin and overall survival rate in treated group was 67%. Drug related complications were noted in 2 newboms. This study illustrates the utility of echocardiography in diagnosing and monitoring PDA in preterm and low birth weight babies with high index of suspicion of this common congenital heart disease. Pharmacological intervention with indomethacin is rewarding with acceptable results.     

Neonatal hemochromatosis and patent ductus venosus: clinical course and diagnostic pitfalls

Background  Neonatal hemochromatosis is a rare metabolic disorder characterized by excessive iron deposition within the liver leading to hepatic failure and portal hypertension. Objective  We describe the clinical course and imaging findings in three infants with neonatal hemochromatosis associated with patent ductus venosus. We paid special attention to the diagnostic challenges encountered in these patients in order to emphasize some of the potential diagnostic pitfalls. Materials and methods  We conducted a comprehensive search of our radiology database of the last 10 years (1999–2008) for the keywords “neonatal hemochromatosis.” Medical records and imaging studies of various modalities were reviewed. Results  Three neonates were found to have neonatal hemochromatosis; all of them were associated with patent ductus venosus. Two of these patients were referred to our tertiary center for embolization of an inaccurately diagnosed hepatic vascular malformation. Two patients underwent successful liver transplantation and one died shortly after referral. Conclusion  The awareness and inclusion of neonatal hemochromatosis in the differential diagnosis of newborns with liver failure and patent ductus venosus has critical treatment implications.     

Patent ductus arteriosus in preterm neonates

Failure of the ductus arteriosus to close within 48–96 hours of postnatal age results in a left to right shunt across the ductus and overloading of the pulmonary circulation. This is more likely to happen in premature neonates with respiratory distress syndrome. Deterioration in the respiratory status on day 3–4 in a ventilated neonate and unexplained metabolic acidosis may be the earliest indicators of a patent ductus arteriosus (PDA). Indomethacin is the main stay of medical management of PDA in preterm neonates. Guidelines for administration of indomethacin have been described in the protocol. Restricted fluid therapy may be beneficial in the prevention of PDA in preterm neonates. Presence of PDA in a term neonate should be investigated to rule out an underlying congenital heart disease.     

Subcostal cross-sectional echocardiographic imaging of patent ductus arteriosus

Summary A modified subcostal short-axis cross-sectional echocardiographic view for imaging the patent ductus arteriosus (PDA) was studied. A total of 22 newborns with PDA and various associated cardiac anomalies and 16 newborns without PDA were examined. The PDA was imaged in the subcostal view in 19 newborns. In the control group, the absence of the PDA was established in 13 newborns and considered probable in three. The PDA was optimally imaged in the subcostal view in patients with normal or enlarged pulmonary artery, mainly those with the hypoplastic left heart. Among the eight patients with small pulmonary artery (pulmonary atresia or severe tetralogy of Fallot), the PDA was imaged in the subcostal view in three and in the suprasternal view in eight. By combining the suprasternal and the subcostal views, the PDA was imaged in each instance.     

Precordial contrast echocardiographic detection of patent ductus arteriosus in small preterm infants

Summary Clinical detection of patent ductus arterious (PDA) remains an important and challenging problem in the small preterm infant with respiratory distress. In this study, PDA was diagnosed in 28 small preterms using an improved contrast echocardiographic method. In these infants, the injection of saline into the aorta generated echoes which were imaged at the pulmonary valve. This was accomplished using a conventional M-mode ultrasound transducer applied at the usual precordial position. Contrast echo studies were compared with the degree of ductal patency shown by single film aortography. Ductal patency was detected by contrast echo in 29 of 31 instances of aortographically proven PDA. Indirect echo indices commonly used for detection of PDA (cardiac chamber enlargement) may be limited since factors other than left-to-right shunt can cause cardiac enlargement in distressed small preterms. This direct contrast echo technique is an easily performed, sensitive, qualitative method for confirmation of the diagnosis of PDA in small preterm infants. This work was supported in part by grant 5507 RR05551-17 from U.S. Public Health Service, Bethesda, Maryland Presented to members of the Cardiology Section at the 20th Annual Meeting of the Society for Pediatric Research, April 29–May 2, 1980, San Antonio, Texas     

Patent ductus venosus

Summary A patent ductus venosus has been reported on only two previous occasions. Both involved adults who presented with recurrent bouts of encephalopathy. We present the case of an infant with complex congenital heart disease and multiple other abnormalities, in whom a patent ductus venosus was an incidental finding at necropsy. The etiology of this condition and the options for management are discussed.     

Unusual ultrasound finding of patent ductus arteriosus in a preterm infant

Summary Patency of the ductus arteriosus (PDA) is a common finding in small premature infants. Recently pulsed-Doppler-cross sectional echocardiography (PD-CSE) has been successfully used in these patients. We report a case of a premature infant with an unusual PD-CSE pattern.     

Treatment of patent ductus arteriosus with ibuprofen

AIM—To evaluate the efficiency and side effects of ibuprofen for the early treatment of patent ductus arteriosus (PDA)and compare it with indomethacin.METHODS—Forty preterm infants with gestational ages of less than 33 weeks, with respiratory distress syndrome (RDS) and echocardiographically confirmed PDA, were randomly assigned at days 2 to 3 of life to receive either intravenous indomethacin 3 × 0.2 mg/kg at 12 hour intervals or intravenous ibuprofen 1 × 10 mg/kg, followed by 5 mg/kg 24 and 48 hours later.RESULTS—PDA closed in 15 of 20 patients from the indomethacin group (75%) and in 16 of 20 (80%) from the ibuprofen group. Seven patients (three indomethacin, four ibuprofen) required a second treatment with indomethacin and in five (three in the indomethacin group and two in the ibuprofen group) the duct was ultimately ligated. Ibuprofen patients had a better urinary output and showed no increase in serum creatinine concentrations compared with the indomethacin group. Ibuprofen was not associated with any other side effect.CONCLUSIONS—Ibuprofen treatment seems to be as efficient as indomethacin in closing PDA on the third day of life in preterm infants with respiratory distress syndrome and seems to have fewer renal side effects.     

Significant correlations between the flow volume of patent ductus venosus and early neonatal liver function: possible involvement of patent ductus venosus in postnatal liver function

BACKGROUND: The biochemical features of portosystemic venous shunt with high flow volume are hypergalactosaemia, hyperammonaemia, prolonged blood coagulation time, and raised serum bile acid concentration. The ductus venosus remains open with shunt flow in most neonates for a certain period after birth. However, the effects of blood flow through the ductus venosus on neonatal liver function remain unclear. OBJECTIVE: To elucidate the effect of patency of the ductus venosus on liver function in early neonates. METHODS: Subjects were divided into three groups by gestational age (group I, 29-32 weeks; group II, 33-36 weeks; group III, 37-41 weeks). The shunt flow volume through the ductus venosus was examined serially using ultrasonography, and correlations between flow volume and liver function in the respective groups were calculated during the first week after birth. RESULTS: Group I had a higher flow volume and later functional closure than the other two groups. Plasma ammonia and serum total bile acid concentrations correlated with flow volume in groups I and II, and blood galactose and galactose 1-phosphate concentrations correlated significantly with flow volume in group III. Percentage hepaplastin also correlated significantly with flow volume in all groups, but plasma vitamin K concentration did not in any group. CONCLUSIONS: Patent ductus venosus has a considerable effect on crucial liver functions such as ammonia detoxification, blood coagulation, and regulation of serum total bile acid concentration in early neonates.     

Indomethacin for closure of patent ductus arteriosous in preterm neonates

Fifteen low birth weight premature infants with a diagnosis of PDA were administered 0·2 mg/kg of indomethacin orally, 3 doses at 12 hourly intervals. The results were compared with 18 prematures who were managed by fluid restriction (80–100 ml/kg/day) and decongestive therapy. Nine out of the 15 cases who received indomethacin met with the criteria of response, compared with only 2 out of 18 in whom there was spontaneous closure (P<0·01). Eleven of 15 cases who received indomethacin survived compared to only 6 of 18 in the control group (P<0·01). Overall mortality due to PDA alone was 58·9 per cent. Indomethacin when administered orally and sufficiently early, is safe and effective in closing PDA in premature infants. This modality of treatment is feasible in the Indian set up.     

Echocardiographic prediction of patent ductus arteriosus in need of therapeutic intervention

Aim: To evaluate the efficacy of various echocardiographic markers in predicting a patent ductus arteriosus (PDA) in need of treatment. Methods: Forty‐five preterm infants with a mean (SD) gestational age of 27.7 (1.9) weeks underwent echocardiography at a postnatal age of 24 ± 6 and 72 ± 6 h. Four echocardiographic markers were studied: ductus diameter, ductal flow Doppler curves, the left atrial to aortic root (LA/Ao) ratio and Doppler pixels representing ductal shunting. Results: Twenty‐eight infants had a PDA with a detectable left‐to‐right shunt. Of these, 12 (43%) were treated for a shunt through the PDA. Ductal diameter was the most accurate echocardiographic marker when it came to predicting a significant shunt, with a sensitivity of 89%, a specificity of 70%, a positive likelihood ratio of 2.97 and a negative likelihood ratio of 0.16 at the age of 72 h. The efficacy of the method at 72 h of age was 84%. The corresponding efficacy of the pulsatile Doppler curve was 72%, percentage of green colour pixels 63% and the LA/Ao ratio 53%. Conclusion: Ductus diameter appears to be the most important variable in determining the need for therapeutic intervention for PDA in preterm infants.     

Management of cardiac dysfunction in neonates with pulmonary hypertension and the role of the ductus arteriosus

Pulmonary hypertension in the neonate is associated with cardiopulmonary disturbances and neurodevelopment morbidity. The patent ductus arteriosus is a persistent fetal shunt that can be pathologic vs supportive in the setting of neonatal pulmonary hypertension. Understanding the underlying pathophysiology of pulmonary hypertension and the cardiopulmonary effects of various phenotypes can guide management in this vulnerable population. In this narrative, we will summarize the physiologic principles of pulmonary hypertension, the impact of the patent ductus arteriosus on various phenotypes, and the utility of serial targeted neonatal echocardiography to individualize clinical assessment and management.     

新生儿动脉导管未闭的高危因素分析

目的：探讨新生儿动脉导管未闭（patent ductus arteriosus,PDA）的高危因素,为PDA的预防提供临床依据。方法：以50例PDA新生儿为病例组,100例非PDA新生儿为对照组,采用χ2检验、t检验或直线相关分析对两组患儿的临床资料进行分析,采用logistic回归分析研究PDA的独立危险因素。结果：PDA的发生与胎龄（r=-0.03,P＜0.05）、出生体重（r=－0.04,P＜0.05）呈负相关。出生时吸氧治疗为保护因素。宫内窘迫、羊水粪染、羊水过少、脐带绕颈、1 min Apgar评分＜8分、母孕期感染、合并缺氧缺血性脑病是新生儿PDA的独立高危因素。结论：避免母孕期感染、早产、低出生体重、缺氧的发生,有利于减少PDA的发生。     

Color Doppler flow mapping of the patent ductus arteriosus in very low birthweight neonates: Echocardiographic and clinical findings

Summary Forty-eight preterm infants (mean birthweight 1.0±0.3 kg; mean gestational age 28±3 weeks) underwent serial echocardiograms and physical examinations in order to determine the correlation between color Doppler flow mapping (CDFM) results and physical findings of a patent ductus arteriosus (PDA), the predictive value of early CDFM as an indicator of subsequent requirement for treatment of a PDA, and to determine the direction and duration of ductal shunting and the rate of ductal closure and opening. CDFM analysis and cardiac physical examination of left-to-right ductal shunting were usually concordant in infants with a large PDA shunt, the most reliable physical finding being increased precordial activity. CDFM studies on day 2 or 3 of postnatal life had prognostic value with regard to subsequent need for closing the PDA. Additional findings included the absence of right-to-left PDA shunting in infants <1 kg and <28 weeks gestation and the absence of ductal reopening in infants in whom it had closed spontaneously. After complete PDA closure using indomethacin, subsequent ductal reopening is uncommon, except in infants <25 weeks gestation and <700 g bodyweight.     

Intravenous Indomethacin therapy in preterm neonates with patent ductus arteriosus

This study examined the response of the patent ductus arteriosus (PDA) to intravenous Indomethacin using serial two dimensional and Doppler echocardiography and documented the complications associated with therapy. Thirty-six preterm neonates who were oxygen and ventilator dependent were studied when they were aged 3-7 days. The PDA initially closed in 22 (61%) and constricted in seven (19%) of the infants. It was non-responsive in five (14%) and the treatment was stopped because of complications in two (6%). Only three (43%) of seven neonates given a second course had PDA closure. In the 25 instances where there was PDA closure following Indomethacin, re-opening was documented echocardiographically on three (12%) occasions. Overall, Indomethacin therapy was successful in 29 (81%) neonates, PDA ligation was required in four (11%) and three died from unrelated causes. Three (8%) neonates developed major complications: multiple gastric perforations in the first, focal ileal perforation in the second, and necrotizing enterocolitis in the third. Treatment failure, PDA ligation and major complications occurred exclusively in neonates less than 28 weeks gestation. In view of the relatively low efficacy and high major complication rate in these extremely preterm infants, a randomized clinical trial needs to be conducted using two dimensional and Doppler echocardiography to allow accurate assessment of the PDA response to intravenous Indomethacin.     

Echocardiographic assessment of patent ductus arteriosus shunt flow pattern in premature infants

AIMS—To identify the patent ductus arteriosus (PDA) shunt flow pattern using Doppler echocardiography; and to assess whether it could be used to predict the development of clinically significant PDA.
METHODS—Premature infants weighing under 1500 g, who required mechanical ventilation, and in whom daily echocardiography could be performed from day 1 until the ductus closed, and on day 7 to confirm closure, were studied. The PDA shunt flow was identified from four Doppler patterns, and the closed pattern of a closed duct was also presented. Clinically significant PDA was diagnosed when there was colour Doppler echocardiographic evidence of left to right ductal shunt associated with at least two of the following clinical signs: heart murmur (systolic or continuous); persistent tachycardia (heart rate>160/min); hyperactive precordial pulsation; bounding pulses; and radiographic evidence of cardiomegaly or pulmonary congestion.
RESULTS—Of 68 infants enrolled into this study, clincally significant PDA developed in 31. The most recordable sequence of transition change of shunt flow pattern for clinically significant PDA was: pulmonary hypertension pattern, to growing pattern, to pulsatile pattern, to closing pattern, to closed pattern. And that for non-clinically significant PDA was: pulmonary hypertension pattern, to closing pattern, to closed pattern. The growing and the pulsatile patterns were mostly documented in infants with clinically significant PDA. The first documented growing pattern to predict clinically significant PDA gave a sensitivity of 64.5% and a specificity of 81.1%; the first documented pulsatile pattern gave a sensitivity of 93.5% and a specificity of 100%.
CONCLUSION—Doppler echocardiographic assessment of PDA shunt flow pattern during the first 4 days of life is useful for predicting the development of clinically significant PDA in premature infants. At that stage, the closing or closed Doppler pattern indicates that infants are not at risk of developing clinically significant PDA; the growing or pulsatile Doppler pattern indicates a continuing risk of developing clinically significant PDA.

     

Diastolic flow velocity of the left pulmonary artery of patent ductus arteriosus in preterm infants

BACKGROUND: The usefulness of diastolic pulmonary flow velocity determined by echocardiography in the assessment of symptomatic patent ductus arteriosus (sPDA) in preterm infants has not been confirmed. METHODS: Echocardiography was performed daily in infants ranging from 23 to 31 gestational weeks of age, and diastolic flow velocity of the left pulmonary artery (DFLPA) was measured. The DFLPA data before indomethacin administration for sPDA were compared with data obtained after indomethacin administration. The normal range of DFLPA was also determined from serial measurements performed in infants who did not develop sPDA during the first 7 days of life. Then, this range was compared with data from infants who did develop sPDA during this time. RESULTS: In infants who underwent indomethacin treatment, DFLPA increased with the development of sPDA and decreased when the symptoms of sPDA disappeared. On the basis of results from serial DFLPA measurement, the sensitivity and specificity of DFLPA for assessing sPDA was found to be 0.82 and 0.83, respectively. CONCLUSIONS: Measurement of DFLPA by echocardiography is a useful method for assessing sPDA in preterm infants.     

Clinical and echocardiographic diagnosis of patent ductus arteriosus in premature neonates

The ductus arteriosus frequently fails to close in premature neonates. Considerable difference in opinion exists around what signifies a hemodynamically significant patent ductus arteriosus (PDA) and how reliable clinical signs are in determining the degree of the left-to-right shunting. Although reliance on clinical signs alone could delay the diagnosis of a PDA, there is insufficient evidence to suggest that early treatment improves outcome. Echocardiography is often used as the gold standard for diagnosing a PDA. A combination of echocardiographic measurements may assist in the early diagnosis of a PDA with a hemodynamically significant degree of left-to-right shunting, especially in extremely premature babies, where closure can be significantly delayed. Decision to treat PDA should be based on a combination of clinical signs and echocardiographic parameters. Monitoring B-type natriuretic peptide may be useful in the diagnosing neonates with symptomatic PDA.