Influence of platelet count, platelet mass index, and platelet function on the spontaneous closure of ductus arteriosus in the prematurity

BACKGROUND

This study aims at evaluating the influence of platelet count, platelet mass index, and platelet function on the spontaneous closure of ductus arteriosus in prematurity.

METHODS

All preterm babies were divided into two groups, including Group 1 with "open PDA" and Group 2 with "closed PDA". The variables of platelet count, mean platelet volume, platelet mass index, and platelet function were analyzed and compared between two groups of patients to identify the factors that significantly influenced spontaneous closure of ductus arteriosus.

RESULTS

Twenty-four patients were in the "open PDA" group, whereas 36 patients were in the "closed PDA" group. Mean GA and BW were 27.6 ± 1.8 (23.1-30.4) and 28 ± 1.6 (23.4-30.6) weeks and 1009 ± 270 (585-1480) g and 1035 ± 298 (505-1500) g in "open PDA" and "closed PDA" groups, respectively (p > 0.05). The incidence of "Collagen-ADP > 130 s" was significantly higher in the "open PDA" group, and the levels of hemoglobin and hematocrit were significantly lower in the "open PDA" group (p < 0.05). Multivariate logistic regression analysis showed that respiratory distress syndrome (OR: 9, CI: 1.5-51.8) and collagen-ADP > 130 s (OR: 5.7 CI: 1.55-21.3) are two independent factors associated with ductal patency.

CONCLUSION

This is the first study in the English literature providing evidence of the influence of platelet dysfunction on the spontaneous closure of ductus arteriosus in prematurity. Longer collagen-ADP duration is identified as a risk factor of ductal closure.

Effectiveness of the critical congenital heart disease screening program for early diagnosis of cardiac abnormalities in newborn infants

Objectives:

To evaluate the effectiveness of critical congenital heart disease (CCHD) screening program for early diagnosis of cardiac anomalies in newborn infants.

Methods:

This is a hospital-based prospective cross-sectional study conducted in the Pediatric and Neonatology Department, King Fahad Hospital at Albaha, Saudi Arabia, between February 2016 and February 2017.

Results:

We screened 2961 (95.4%) of 3103 patients in a nursery unit; 142 (4.6%) patients were not screened. The test was positive in 114 (3.9%) patients and negative in 2847 (96.1%). There were 94 (3.2%) false positives and 20 (0.7%) true positives. Critical cardiac defects were diagnosed in 7 (0.2%) patients of all screened infants, and severe pulmonary hypertension was diagnosed in 13 (0.4%) patients. True negative results were found in 2841(96%) patients, and no cardiac defect was diagnosed, whereas false negative results were seen in 6 (0.2%) patients diagnosed with ventricular septal defect. The sensitivity was 77%, and the specificity was very high at 97%, with a positive predictive value of 18%, and a negative predictive value of 99.8% (95% confidence interval 13.78-19.18, p=0.0001).

Conclusion:

Pulse oximetry was found to be easy, safe, sensitive, and highly specific for diagnosis of CCHD.

Contemporary outcomes of percutaneous closure of patent ductus arteriosus in adolescents and adults

Background

Catheter based treatment has gained wide acceptance for management of patent ductus arteriosus (PDA) ever since its introduction. Percutaneous closure in adults can be challenging because of anatomical factors including large sizes, associated pulmonary arterial hypertension (PAH) and co-morbidities. This study aimed to provide comprehensive contemporary data on the safety and efficacy of percutaneous device closure of PDA in adult and adolescent population at a large referral center.

Methods

This single-center retrospective analysis included 70 patients (33 adolescents and 37 adults) who underwent successful percutaneous device closure of PDA between January 2011 and February 2017.Baseline patient demographics, clinical characteristics, procedural and device related variables, and immediate outcomes during hospital stay were recorded. Patients were followed up for residual shunt and complications.

Results

Of 70 PDA device closure cases, 71.4% were females; the mean age was 23 years (range:10-58years). Devices used were 4-Cook’s detachable coils, 64-occluders (ADO-I and II, Lifetech, Cardi-O-Fix), 1-vascular plug and 1-ventricular septal occluder device. Device success was achieved in all including those with very large PDAs. At 24-h post-procedure, the success rate of transcatheter intervention was 95.7%. At 6-months follow up, complete closure was observed in all (mean follow up duration-531 days). In patients with severe PAH, significant immediate and sustained reduction of the mean pulmonary pressure was observed(77 mmHg to 33 mmHg;P = 0.014). No procedure-related complications including death, device embolization and stenosis of aorta or pulmonary artery occurred.

Conclusions

In contemporary practice, percutaneous device closure is an effective and safe treatment option for adolescent and adult PDA patients.

Handle With Care: A Ductus Arteriosus Aneurysm in an Elderly Patient

A ductus arteriosus aneurysm (DAA) was corrected with an 18 mm Amplatzer patent foramen ovale occluder. DAA is a rare finding, with sporadic cases reported (the vast majority in children and infants). In the elderly, it poses serious therapeutic challenges, as the risk of rupture is counterbalanced by the high risk of its correction, which requires surgery or placement of an endovascular prosthesis in a critical region such as the aortic arch.

Familial clustering of congenital deafness, patent ductus arteriosus, Eisenmenger complex, and differential cyanosis: A case report

RATIONALE

Few studies had reported syndromes that include patent ductus arteriosus (PDA) with Eisenmenger syndrome and congenital deafness clustered in male siblings without facial, skeletal, or mental abnormalities.

PATIENT CONCERNS

Two brothers, who were deaf and had PDA with Eisenmenger complex, were first seen at our Cardiology clinic at the ages of 25 and 41, respectively. They presented with progressive dyspnea on exertion. Upon physical examination, both brothers had clubbing and/or cyanotic toes, normal fingers, and without facial, skeletal, ophthalmological, or mental abnormalities.

DIAGNOSES AND INTERVENTIONS

Echocardiography and multidetector computed tomography revealed large PDAs in both brothers. Cardiac catheterization showed bidirectional shunting via the PDA.

OUTCOMES AND LESSONS

Familial clustering of Eisenmenger PDA and congenital deafness is rare. Further studies are warranted to define possible genetic links.

Comparison of the Mortality and In-Hospital Outcomes of Preterm Infants Treated with Ibuprofen for Patent Ductus Arteriosus with or without Clinical Symptoms Attributable to the Patent Ductus Arteriosus at the Time of Ibuprofen Treatment

The aim of this study was to assess the differences in the mortality and in-hospital outcomes of preterm infants with < 28 weeks of gestation who received ibuprofen treatment according to the presence of clinical symptoms (any of oliguria, hypotension, or moderate to severe respiratory difficulty) attributable to hemodynamically-significant patent ductus arteriosus (hsPDA) at the time of first ibuprofen treatment. In total, 91 infants born from April 2010 to March 2015 were included. Fourteen infants (15.4%) received ibuprofen treatment when there were clinical symptoms due to hsPDA (clinical symptoms group). In clinical symptoms group, infants were younger (25 [23-27] vs. 26 [23-27] weeks; P = 0.012) and lighter (655 [500-930] vs. 880 [370-1,780] grams; P < 0.001). Also, the clinical risk index for babies (CRIB)-II scores were higher and more infants received invasive ventilator care ≤ 2 postnatal days. More infants received multiple courses of ibuprofen in clinical symptoms group. Although the frequency of secondary patent ductus arteriosus (PDA) ligation and the incidence of bronchopulmonary dysplasia (BPD) was higher in the clinical symptoms group in the univariate analysis, after multivariate logistic regression analysis adjusting for the CRIB-II score, birthweight, birth year, and the invasive ventilator care ≤ 2 postnatal days, there were no significant differences in mortality, frequency of secondary ligation and in-hospital outcomes including necrotizing enterocolitis (NEC), intraventricular hemorrhage (IVH), BPD or death. Our data suggest that we can hold off on PDA treatment until the clinical symptoms become prominent.

The serial changes of perfusion index in preterm infants with patent ductus arteriosus: is perfusion index clinically significant?

BACKGROUND

Perfusion Index (PI) which reflects the peripheral blood flow may help early detection and treatment decision of hemodynamically significant patent ductus arteriosus (hsPDA) in preterm infants. The present study is designed to analyze the usefulness of PI level in early detection of hsPDA in preterm infants.

METHODS

Preterm infants born before 36 gestational weeks were assessed for PI and simultaneous echocardiography. Based on echocardiography, each infant is categorized into no-PDA (group 1), non-hsPDA (group 2) and hsPDA (group 3). Heart rate (HR), mean arterial pressure (MAP), body temperature and oxygen saturation (SpO2) and concomitant PI were measured on days 1, 2, 3 and 4.

RESULTS

In all preterm infants (N.=42) PI significantly increased from 0.7 on day 1 to 1.4 on day 4. The HR did not change by the days; however, the MAP increased on days 3 and 4 compared to day 1. In hsPDA group, the median PI was 0.7 (IQR, 0.4) on day 1 compared to 0.9 (IQR, 0.2) on day 2. PI is significantly lower in hsPDA group compared to no-PDA group on day 1 and 2; however, this difference disappeared at 48 hour on the intravenous ibuprofen treatment (on day 3 and 4).

CONCLUSIONS

PI may predict the perfusion disorder and help to decide for treatment of hsPDA and was also helpful to monitor the response to treatment in hsPDA patients.

A systematic review of trends and patterns of congenital heart disease in children in Nigeria from 1964-2015

BACKGROUND

Congenital heart diseases cause significant childhood morbidity and mortality. Several restricted studies have been conducted on the epidemiology in Nigeria. No truly nationwide data on patterns of congenital heart disease exists.

OBJECTIVES

To determine the patterns of congenital heart disease in children in Nigeria and examine trends in the occurrence of individual defects across 5 decades.

METHOD

We searched PubMed database, Google scholar, TRIP database, World Health Organisation libraries and reference lists of selected articles for studies on patterns of congenital heart disease among children in Nigeria between 1964 and 2015. Two researchers reviewed the papers independently and extracted the data. Seventeen studies were selected that included 2,953 children with congenital heart disease.

RESULTS

The commonest congenital heart diseases in Nigeria are ventricular septal defect (40.6%), patent ductus arteriosus (18.4%), atrial septal defect (11.3%) and tetralogy of Fallot (11.8%). There has been a 6% increase in the burden of VSD in every decade for the 5 decades studied and a decline in the occurrence of pulmonary stenosis. Studies conducted in Northern Nigeria demonstrated higher proportions of atrial septal defects than patent ductus arteriosus.

CONCLUSIONS

Ventricular septal defects are the commonest congenital heart diseases in Nigeria with a rising burden.

Patent Ductus Arteriosus in Preterm Infants

Despite a large body of basic science and clinical research and clinical experience with thousands of infants over nearly 6 decades,(1) there is still uncertainty and controversy about the significance, evaluation, and management of patent ductus arteriosus in preterm infants, resulting in substantial heterogeneity in clinical practice. The purpose of this clinical report is to summarize the evidence available to guide evaluation and treatment of preterm infants with prolonged ductal patency in the first few weeks after birth.

Safety and Efficacy of Transcatheter Closure of Patent Ductus Arteriosus With Severe Mitral Regurgitation in Adults

BACKGROUND

Transcatheter closure is the usual treatment for patent ductus arteriosus (PDA), but its safety and efficacy have not been reported in adult PDA patients with severe mitral regurgitation.

STUDY DESIGN

A retrospective study on 27 consecutive patients diagnosed with PDA and severe mitral regurgitation and treated using transcatheter closure between September 2010 and September 2012 at the Department of Cardiology of Changhai Hospital in Changhai, China. Left ventricular (LV) diastolic volume and function, pulmonary artery pressure, and instantaneous reverse-flow volume were examined by echocardiography before PDA closure, immediately after closure, and 1 year after closure.

RESULTS

After the procedure, the LV diastolic volume (P<.05) and instantaneous reverse-flow volume (P<.001) were significantly decreased. There was no effect on the ejection fraction (P>.05). Pulmonary arterial systolic pressure was unchanged 1 year after closure (from 46.41 ± 19.92 mm Hg to 45.43 ± 13.64 mm Hg; P=.58). All procedures were uneventful and only mild complications occurred (hemolysis in 2 cases, subcutaneous hematoma in 4 cases, and fever in 2 cases).

CONCLUSION

Transcatheter closure can decrease the LV volume and instantaneous reverse-flow volume in adult PDA patients with severe mitral regurgitation. This procedure is effective and has a good safety profile.

[Value of amino-terminal pro-brain natriuretic peptide as a predictive marker of symptomatic patent ductus arteriosus in preterm infants]

OBJECTIVE

To study the value of amino-terminal pro-brain natriuretic peptide (NT-proBNP) in predicting symptomatic patent ductus arteriosus (sPDA) in preterm infants.

METHODS

Preterm infants born at a gestational age (GA) of ≤ 32 weeks and diagnosed with patent ductus arteriosus (PDA) by echocardiography within 48 hours after birth between June 2014 and April 2015 were selected as subjects. Their clinical manifestations were observed, and serum NT-proBNP levels were measured and echocardiography was performed at 3 and 5 days after birth. The infants were divided into sPDA group and asymptomatic PDA (asPDA) group based on their clinical manifestations and the results of echocardiography. The correlations between serum NT-proBNP level and echocardiographic indices were analyzed. Serum NT-proBNP levels were compared between the two groups. The receiver operator characteristic (ROC) curve was applied to determine the sensitivity and specificity of serum NT-proBNP in the prediction of sPDA.

RESULTS

A total of 69 preterm infants were enrolled in this study, with 13 infants in the sPDA group and 56 infants in the asPDA group. Serum NT-proBNP level was positively correlated with the diameter of the arterial duct (r=0.856; P<0.05)and the ratio of left atrial diameter to aortic root diameter (LA/AO) (r=0.713; P<0.05). At 3 and 5 days after birth, the serum NT-proBNP levels in the sPDA group were significantly higher than those in the asPDA group (P<0.05). The area under the ROC curve (AUC) for the prediction of sPDA by NT-proBNP levels at 3 days after birth was 0.949 (95% CI: 0.892-1.000; P<0.001), with a cut-off value of 27 035 pg/mL (sensitivity: 92.3%; specificity: 94.6%); the AUC for the prediction of sPDA by NT-proBNP levels at 5 days after birth was 0.924 (95% CI: 0.848-1.000; P<0.001), with a cut-off value of 6 411 pg/mL (sensitivity: 92.3%; specificity: 92.9%).

CONCLUSIONS

NT-proBNP may be a quantitative index for shunt volume. The measurement of serum NT-proBNP levels on 3 and 5 days after birth may be useful to predict sPDA in preterm infants.

Postnatal diagnosis of maternal congenital heart disease: missed opportunities

A 30-year-old primigravida with no known comorbidities presented to the emergency department at 29+6/40 gestation, with breathlessness. The initial diagnosis was pulmonary embolism, which was later revised following initial investigations and considered to be pre-eclampsia/HELLP (haemolysis, elevated liver enzymes, low platelets) syndrome. Following caesarean section and delivery of a live baby, the patient had episodes of cyanotic hypoxia and was admitted to intensive care. A provisional diagnosis of idiopathic pulmonary hypertension was performed. Decompensation led to transfer to a specialist intensive care unit for extracorporeal membrane oxygenation, where a diagnosis of patent ductus arteriosus and Eisenmenger's syndrome was made. Heart disease is the leading indirect cause of maternal death, and Eisenmenger's syndrome in pregnancy carries a 50-65% mortality. A literature review demonstrated that this is the only reported case of a postnatal diagnosis of Eisenmenger's syndrome. We considered missed opportunities to make an earlier diagnosis, so that patients and doctors will benefit from the lessons we learnt.

The new occlutech duct occluder: immediate results, procedural challenges, and short-term follow-up

OBJECTIVE

The aim of this study was to assess the immediate and short-term results of transcatheter closure of patent ductus arteriosus (PDA) using the Occlutech duct occluder (ODO).

BACKGROUND

The ODO is a new self-expanding nitinol device. Its body is wider at the pulmonary artery end than the aortic end. It is available in longer lengths than the Amplatzer duct occluder.

METHODS

Twenty-two ODO implants were attempted in successive children referred for transcatheter device occlusion of PDAs ≥1 mm in diameter.

RESULTS

Median patient age was 2.4 years (range, 0.7-17.5 years), median weight was 13.1 kg (range, 6.3-40 kg), and median PDA diameter was 1.9 mm (range, 1-4.3 mm). Twenty-one out of 22 patients (95%) had successful ODO implantation. One device was withdrawn before release because it did not reach the pulmonary artery end of a long duct. Median procedure time was 40 minutes (range, 26-60 minutes) and fluoroscopy time was 4.5 minutes (range, 2.7-13.3 minutes). Occlusion rates were 19/21 (90%) at the end of the procedure, 20/21 (95%) at 24-48 hours post procedure, and 21/21 (100%) on echocardiography at a median follow-up of 4 weeks (range, 2-16 weeks). There were no device-related complications. Two infants had femoral artery occlusion, successfully treated by heparinization and thrombolysis.

CONCLUSION

This first formal clinical evaluation of the ODO indicates that it is safe and effective in occluding small-to-moderate size ducts, up to a diameter of 4.3 mm. The device produced equivalent results to the Amplatzer duct occluder. Further evaluation is required to assess whether its shape and longer length make it superior for closing large and long ducts.

Platelets and platelet-derived growth factor in closure of the ductus arteriosus

The crucial role of platelets in the permanent closure of the ductus arteriosus has recently been elucidated in an animal model; however, clinical studies investigating the impact of platelet count on ductal patency have conflicting results. Our aim is to compare platelet count, indices and serum platelet-derived growth factor levels in preterms with and without ductal patency. Preterms with a gestational age of 27-30 weeks followed up during a twelve-month period in the neonatal intensive care unit of Adnan Menderes University Hospital were enrolled. Infants underwent echocardiographic evaluation starting on the second day and subsequently assessed every other day until ductal closure was achieved, or upon clinical signs of reopening. Platelet-derived growth factor was measured on the second and fifth days of life. Eleven very low birth weight infants who subsequently required medical treatment for patent ductus arteriosus were compared with twenty-three infants with closed ductus. Although platelet count and indices were similar, median serum plateletderived growth factor levels on day 5 were significantly lower among babies who subsequently required medical treatment for ductal patency (874.6 vs 1099.6 pg/ml). The current study points out a possible association between serum platelet-derived growth factor levels and ductal closure. Our results suggest that platelet-derived growth factor may play a role in ductal closure independent from platelet count and might be used as an adjunct surrogate for prediction of future need for treatment for hemodynamically significant patent ductus arteriosus in preterm infants.

Management of patent ductus arteriosus in premature infants

Patency of the ductus arteriosus is required for fetal survival in utero. In infants born prematurely, ductus fails to close and shunt reverses from left to right. Incidence of patent ductus arteriosus (PDA) is inversely proportional to the gestational age. A large PDA (>1.5 mm diameter) with left to right shunt in very low birth weight infants can cause pulmonary edema, congestive heart failure, pulmonary hemorrhage and increase the risk for bronchopulmonary dysplasia. Attempts to prevent or close the duct by pharmacological or surgical methods have not changed the morbidity or the long term outcome. Pharmacological treatment with indomethacin or ibuprofen is successful in 75 to 80 % of infants but its use also exposes these infants to undesirable side effects like gastrointestinal bleeding, perforation and necrotizing enterocolitis. Prophylactic therapy with indomethacin or ibuprofen to prevent PDA has not altered the morbidity or long term outcome. Currently, there is a dilemma as to how to treat, when to treat and whom to treat. Recent literature suggests a trial of conservative management during the first week followed by selective use of anti-inflammatory drugs. Surgical ligation is reserved for infants who fail medical therapy and still remain symptomatic. Spontaneous closure of the PDA has been reported in up to 40-67 % of very low birth weight (VLBW) infants by 7 d. In this review authors discuss these controversies and propose a more rational approach.

[Clinical analysis of 165 extremely low birth weight infants]

OBJECTIVE

To analyze the clinical features and prognosis of extremely low birth weight infants (ELBWI).

METHOD

Data of totally 165 hospitalized ELBWI between August 1st, 2008 and November 30th, 2013 in Hunan Children's Hospital were analyzed. The information of general data and births, prenatal care, delivery room stabilization, transfer information, complications, treatment, outcome and follow up were summarized.

RESULT

(1) One hundred and sixty-five ELBWI were involved, their mean gestational age was (28.4±2.4) weeks, mean birth weight(910.9±93.1) g. (2) Rate of delivery in tertiary hospital was 46.7% (77/165) and prenatal steroids exposure was found in 52.1% (86/165). None of the cases were treated with continuous positive airway pressure (CPAP) in delivery room. (3) Rate of infants who were transfered to the class III b neonatal ward within 12 hours after birth was 58.8% (97/165). (4) The main complications of them included neonatal respiratory distress syndrome(NRDS, 77.0%, 127/165), bronchopulmonary dysplasia (BPD, 70.1%, 75/107), patent ductus arteriosus (PDA, 50.0%, 40/80), preterm retinopathy (ROP, 43.0%, 46/107), sepsis 39.4% (65/165), intraventricular hemorrhage (IVH, 34.8%, 49/141), necrotizing enterocolitis (NEC, 8.0%, 7/88). (5) TREATMENT: 97.6% (161/165) received oxygen therapy and 66.1% (109/165) received mechanical ventilation, 55.2% (91/165) used CPAP. 89.8% (114/127) of the NRDS used PS; 44.0% (33/75) of the BPD used low dose dexamethasone, 32.0% (24/75) used low dose nitric oxide; 60.0% (24/40) of the PDA used medication. 32.6% (15/46) of the ROP received laser photocoagulation. The average time of beginning enteral feeding was 2.0 d, the mean time to achieve full gastrointestinal feeding was 43.4 d. (6) OUTCOME: rate of survival in 165 cases with ELBWI was 51.5% (85/165), treatment was abandoned in 37.6% (62/165), total mortality was 48.5% (80/165). There were significant difference in survival rate between different birth weight group, gestational age group and admission age group (χ2=11.498, 8.789, 13.157, all P<0.05); There was significant difference in rate of giving up treatment between different birth weight and admission age groups (χ2=10.448, 8.259, all P<0.05). The primary cause of death was economic factor and worrying about prognosis. (7) Follow up: rate of neurodevelopmental impairment (NDI) in part of follow up cases was 27.9% (12/43).

CONCLUSION

ELBWI have many severe complications and sequelae, which need complex treatment and long hospital stay with a low survival rate. In order to improve the level of treatment, we need to improve the rate of prenatal steroids, carry out intrauterine and postnatal, transport of ELBWI to III b neonatal ward as early and rationally as possible, give professional, sophisticated and integrated treatment technologies as far as possible.

Transcatheter occlusion of patent ductus arteriosus: success rate and complications 5 years experience: single center in isfahan

BACKGROUND AND AIM

Percutaneous occlusion of patent ductus arteriosus (PDA) has become increasingly attractive with the evolution of devices and techniques. This study aimed to report the total experience of a novel arterial occlusion device (Duct Occlude pfm) and Amplatzer.

METHODS

A descriptive study which selected non-randomized pediatric patients with patent ductus arteriosus (PDA) was performed between May 2007 to February 2012 on 99 children aged 8 months to 16 years who underwent attempted closure of PDA. Transcatheter occlusion was attempted in all the cases of coil through a 4-5 F and for Amplatzer 6-7 F delivery catheter.

FINDINGS

Devices were successfully deployed in 98% of patients. Amplatzer was used for thirty four patients (34%) due to medium to large PDA and coil was selected for sixty five patients (66%) due to small to medium size PDA.One day after the procedure, complete occlusion was accomplished in 42 (69%) out of 61 patients in whom the detachable coil device had been used on color-flow Doppler echocardiography. Embolization of a coil occurred on 1 occasion.

CONCLUSION

METHODS of detachable coil and Amplatzer type occlusion system compares favorably with other methods of transcatheter PDA occlusion.

Cardiovascular magnetic resonance of cardiac function and myocardial mass in preterm infants: a preliminary study of the impact of patent ductus arteriosus

BACKGROUND

Many pathologies seen in the preterm population are associated with abnormal blood supply, yet robust evaluation of preterm cardiac function is scarce and consequently normative ranges in this population are limited. The aim of this study was to quantify and validate left ventricular dimension and function in preterm infants using cardiovascular magnetic resonance (CMR). An initial investigation of the impact of the common congenital defect patent ductus arteriosus (PDA) was then carried out.

METHODS

Steady State Free Procession short axis stacks were acquired. Normative ranges of left ventricular end diastolic volume (EDV), stroke volume (SV), left ventricular output (LVO), ejection fraction (EF), left ventricular (LV) mass, wall thickness and fractional thickening were determined in "healthy" (control) neonates. Left ventricular parameters were then investigated in PDA infants. Unpaired student t-tests compared the 2 groups. Multiple linear regression analysis assessed impact of shunt volume in PDA infants, p-value ≤ 0.05 being significant.

RESULTS

29 control infants median (range) corrected gestational age at scan 34+6(31+1-39+3) weeks were scanned. EDV, SV, LVO, LV mass normalized by weight and EF were shown to decrease with increasing corrected gestational age (cGA) in controls. In 16 PDA infants (cGA 30+3(27+3-36+1) weeks) left ventricular dimension and output were significantly increased, yet there was no significant difference in ejection fraction and fractional thickening between the two groups. A significant association between shunt volume and increased left ventricular mass correcting for postnatal age and corrected gestational age existed.

CONCLUSION

CMR assessment of left ventricular function has been validated in neonates, providing more robust normative ranges of left ventricular dimension and function in this population. Initial investigation of PDA infants would suggest that function is relatively maintained.

The timing of surgical ligation for patent ductus arteriosus is associated with neonatal morbidity in extremely preterm infants born at 23-25 weeks of gestation

The purpose of this study was to evaluate prognostic factors associated with surgical ligation for patent ductus arteriosus (PDA) in extremely preterm infants born at the limits of viability. Ninety infants who were born at 23-25 weeks of gestation and who received surgical ligation were included and their cases were retrospectively reviewed. Infants were classified into two different groups: survivors with no major morbidity (N), and non-survivors or survivors with any major morbidity (M). Clinical characteristics were compared between the groups. Possible prognostic factors were derived from this comparison and further tested by logistic regression analysis. The mean gestational age and the mean birth weight of M were significantly lower than those of N. Notably, the mean postnatal age at time of ligation in N was significantly later than that of the other group (17 ± 12 vs 11 ± 8 days in N and M, respectively). An adjusted analysis showed that delayed ligation (>2 weeks) was uniquely associated with a significantly decreased risk for mortality or composite morbidity after surgical ligation (OR, 0.105; 95% CI, 0.012-0.928). In conclusion, delayed surgical ligation for PDA (>2 weeks) is associated with decreased mortality or morbidities in extremely preterm infants born at 23-25 weeks of gestation.

Therapeutic manipulation of the ductus arteriosus: current options and future prospects

The ductus arteriosus is a large fetal vessel connecting the pulmonary artery with the aorta and allowing right ventricular blood to bypass the unexpanded lungs. At birth, with the start of lung ventilation and the attendant rise in blood oxygen tension, the ductus closes and the cardiovascular system acquires its final arrangement. However, in the prematurely born infant, this shunt may remain patent (patent ductus arteriosus--PDA) with adverse consequences on hemodynamic homeostasis. Conversely, there are cardiac malformations in which patency of the duct is required to maintain the pulmonary or systemic circulation prior to corrective surgery. Based on the notion that patency is an active process sustained primarily by prostaglandin (PG) E₂, PDA is currently managed with synthesis inhibitors, indomethacin or ibuprofen, while any necessary persistence of the duct after birth is achieved with the infusion of PGE₁. However, the former procedure presents a relatively high incidence of failures for the likely combination of the 2 events: the relaxing influence of the agents compensating for the loss of PGE₂ and the immaturity of the oxygen‑triggered contractile mechanism. On the other hand, PGE₁ treatment loses some of its efficacy with time and may also be complicated by troublesome side effects. This article presents possible new approaches to therapy still based on the manipulation of the relaxing mechanism(s) responsible for duct patency. At the same time, however, the idea is put forward that the management of these sick infants may find its definitive solution only with tools being designed on the operation of the oxygen‑sensing/effector system.