SEARCH · PubMed Health
Explore indexed PubMed citations for clinical trials, systematic reviews and public health research. Read source abstracts and follow each citation to its original PubMed record.
Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.
New insights into the closure of the ductus arteriosus may lead to more effective nonsurgical treatment in patent ductus arteriosus. ET-1 agonists may prove useful in future pharmacologic interventions.
A technique for closure of the complicated ductus arteriosus is described which has proved both simple and safe. The technique embodies the use of profound hypothermia, low flow, and direct suture of the pulmonary end of the ductus arteriosus through a pulmonary arteriotomy. No operative deaths have occurred among 4 patients so treated, and no complications from air embolism or hemorrhage have been encountered.
AIMS: We reported the incidence, clinical manifestations and outcome of patent ductus arteriosus (PDA) in full-term infants by screening echocardiography. METHODS AND RESULTS: Total 1230 infants received echocardiographic screening and periodic follow-up. On the third day of life, there were 109 infants with isolated ductus arteriosus aneurysm (DAA), those with persistent patency of the ductus arteriosus (DA) in 26. The DA closed within 48 h in 828 infants, and persisted beyond 48 h in 180. The incidence of PDA in full-term infants was 0.91, 0.83 and 0.66% at 1, 4 and 6 months follow-up, and 0.82, 0.73 and 0.64% if infants with DAA were excluded. Infants with PDA had lower birth body weight (BBW) than those with closed DA (p = 0.02). The DA width on the third day of life ranged from 0.23 to 0.43 cm (0.32 +/- 0.08 cm) and 0.08 to 0.44 cm (0.16 +/- 0.06 cm) in infants with or without PDA, respectively, which was significantly different (p < 0.05). The sensitivity, specificity, predictive positive and negative values were 87.5, 92.5, 36.8 and 99% respectively for the cuff-off point at 0.25 cm of DA width. CONCLUSIONS: Risk factors in infants with PDA included lower BBW and larger measured DA width at the third day of life. We predicted the arterial duct would close if DA width <0.25 cm, and suggested follow up earlier if >0.25 cm on the third day of life.
Patent ductus arteriosus with pulmonary hypertension and right to left shunting of blood flow was diagnosed in a 9-month-old female cat. Because of the pulmonary hypertension, the cat did not have typical signs of patent ductus arteriosus; thus, cardiac angiography and catheterization were utilized to confirm the diagnosis. The patent duct was successfully occluded with a vascular clip.
Circular strips of ductus arteriosus from lambs of gestational age between 90 and 144 days (term 147 days) were studied in vitro at low (8--16 torr (1 torr = 133.322 Pa)) and high (426--622 torr) PO2. Potassium- and oxygen-induced contractions increased with the gestational age and attained a maximum at term. At low PO2, ibuprofen, a blocker of prostaglandin synthesis, produced a dose-dependent contraction of the ductus at all ages and enhanced the potassium-induced contraction of the immature ductus (90--124 days). Both effects were relatively greater in the 103- to 107-day gestational group. At that age, ibuprofen also potentiated the oxygen-induced contraction. These findings, while confirming that a prostaglandin is involved in ductus patency, indicate that the prostaglandin-relaxing mechanism becomes functional at an early stage of gestation and reaches maximal activity before term. The existence of an active, prostaglandin-mediated relaxation in the preterm ductus may account, in part, for the reduced responsiveness of the vessel to oxygen. It is confirmed that ibuprofen and other nonsteroidal antiinflammatory drugs are well suited for the management of the premature infant with patent ductus arteriosus.
Indomethacin produces constriction and hypoxia of the fetal ductus arteriosus. This is associated with death of smooth muscle cells in the ductus wall and an increased incidence of patent ductus arteriosus in the newborn period. We used fetal sheep to determine which factors are responsible for indomethacin-induced hypoxic cell death. Cell death in the ductus wall is directly related to the degree of indomethacin-induced ductus constriction and is present at both moderate and marked degrees of constriction. Both moderate and marked degrees of ductus constriction reduce vasa vasorum flow to the ductus (moderate = 69 +/- 25%; marked = 30 +/- 16% of preinfusion values) and increase the thickness of the ductus wall. In contrast, ductus luminal blood flow is not affected by moderate degrees of constriction and is reduced only after marked constriction. Although indomethacin increases ductus tone, it has no effect on ductus oxygen consumption. These findings suggest that the hypoxic cell death that occurs during the early stages of indomethacin-induced constriction is primarily due to changes in vasa vasorum blood flow and muscle media thickness.
OBJECTIVE: Our objective was to study the pharmacokinetics of ibuprofen in premature infants with patent ductus arteriosus on day 3 and day 5 after birth. METHODS: Ibuprofen was administered on days 3, 4, and 5 by a 15-minute intravenous infusion of 10, 5, and 5 mg/kg, respectively, with the aim of closing the ductus arteriosus. Blood samples were drawn at time zero and at 0.5, 1, 2, 4, 12, and 24 hours after the first and third doses. Ibuprofen plasma concentrations were assayed by HPLC. RESULTS: A total of 27 premature infants were included (gestational age, 28.6 +/- 1.9 weeks; birth weight, 1250 +/- 460 g; values are mean +/- standard deviation). Ibuprofen pharmacokinetics followed a 2-compartment open model. Between the first and third doses (day 3 and day 5) there was a significant decrease of the volume of distribution of the central compartment (Vd(c)) (0.244 versus 0.171 L/kg; P =.03) and area under the plasma concentration-time curve (524 versus 447 mg. h/L; P =.01). The decrease in Vd(c) was most pronounced in patients with a closing ductus. Total body clearance and plasma half-life did not change significantly. No significant differences were observed in ibuprofen peak plasma concentrations after the first and third doses in relation to ductal status after treatment. CONCLUSION: Ibuprofen pharmacokinetics showed a large interindividual variation in premature infants during treatment for patent ductus arteriosus, and significant changes may occur between day 3 and day 5 after birth in those infants with a closing ductus. These findings may have implications for the treatment schedule with ibuprofen in patients with patent ductus arteriosus.
OBJECTIVES: To determine the causes and outcome of residual shunting after transcatheter occlusion of persistent ductus arteriosus with the Rashkind double umbrella occluder, and to determine the potential of the device to produce obstruction to flow in the aorta and left pulmonary artery. DESIGN: Angiographic examination of morphology of ductus followed by prospective clinical and ultrasound evaluation (including cross sectional imaging, colour flow mapping, and pulse wave Doppler) of all patients undergoing occlusion of persistent ductus arteriosus between October 1987 and July 1992. PATIENTS: 140 patients with ages between 0.5 and 78 (median 3.8) years and weights between 6.8 and 74 (median 13.8) kg. INTERVENTIONS: Attempted implantation of the Rashkind double umbrella ductus occluder under angiographic control through a transvenous (n = 136) or transarterial (n = 4) approach. MAIN OUTCOME MEASURES: Successful occlusion of ductus; frequency, pattern, and prognosis of residual shunts; Doppler velocities in left pulmonary artery and aorta; volume loading of the left heart. RESULTS: Including reocclusions the overall rate of successful occlusion was 96%. A total of six devices embolised at the time of operation (4.3%) with no sequelae. There were no anatomical factors that predicted a poor outcome, but suboptimal positioning of the device led to a significantly higher incidence of residual shunts (p < 0.001). Colour flow mapping correctly identified shunts that were unlikely to close spontaneously (n = 9) and to date seven have undergone successful closure with a second device. Encroachment of device legs produced statistically (p < 0.001) but not clinically significant increases in left pulmonary artery Doppler velocities that diminished with time. CONCLUSIONS: Transcatheter occlusion provides a safe and effective means of closing a persistent ductus arteriosus. Doppler colour flow mapping is necessary for follow up and shows those ducts requiring reocclusion. The device did not produce significant disturbance to flow in the pulmonary arteries or aorta.
Postanatal closure of the ductus arteriosus depends on the level of O2 to which it is exposed. Certain vasoactive substances may also play a role in this constriction. The response to O2 is not as well developed in immature fetal animals and this probably explains the high incidence of patent ductus arteriosus (PDA) in premature human infants. The magnitude of shunting through a PDA depends on its size and the relationship between the pulmonary and systemic vascular resistances. Factors affecting the pulmonary vascular resistance (such as hypoxia) will therefore affect the shunt. The ability of the infant to handle the volume overload also depends on maturity of the infant since myocardial development may not be complete even at term. The clinical manifestations and management of PDA with and without pulmonary disease are described. Recent attempts at pharmacological closure of the PDA are presented.
We report our experience in a 13-month-old boy undergoing transcatheter coil occlusion of a patent ductus arteriosus. Constriction of the ductus arteriosus with subsequent relaxation resulted in inadvertent coil embolization. This case report and review of the literature have implications for transcatheter treatment of persistent ductus arteriosus.
BACKGROUND: At birth, the increase in oxygen causes contraction of the ductus arteriosus, thus diverting blood flow to the lungs. Although this contraction is modulated by substances such as endothelin and dilator prostaglandins, normoxic contraction is an intrinsic property of ductus smooth muscle. Normoxic inhibition of potassium channels causes membrane depolarization and calcium entry through L-type calcium channels. However, the studies reported here show that after inhibition of this pathway there is still substantial normoxic contraction, indicating the involvement of additional mechanisms. METHODS AND RESULTS: Using ductus ring experiments, calcium imaging, reverse-transcription polymerase chain reaction, Western blot, and cellular electrophysiology, we find that this depolarization-independent contraction is caused by release of calcium from the IP3-sensitive store in the sarcoplasmic reticulum, by subsequent calcium entry through store-operated channels, and by increased calcium sensitization of actin-myosin filaments, involving Rho-kinase. CONCLUSIONS: Much of the normoxic contraction of the ductus arteriosus at birth is related to calcium entry through store-operated channels, encoded by the transient receptor potential superfamily of genes, and to increased calcium sensitization. A clearer understanding of the mechanisms involved in normoxic contraction of the ductus will permit the development of better therapy to close the patent ductus arteriosus, which constitutes approximately 10% of all congenital heart disease and is especially common in premature infants.
Among 425 pre-term low birthweight babies who survived more than 48 hours there were 130 with idiopathic respiratory distress syndrome, 73 of whom received ventilation for their disease. The ductus arteriosus was considered patent by clinical criteria in 41 of these babies, all but 1 of whom had a murmur. Of the remaining 32 infants there were 2 babies only who died and both were found to have a patent ductus arteriosus which had not been detected clinically. Another baby died whilst being ventilated for idiopathic respiratory distress syndrome and although autopsy information is not available it seems likely that factors other than a patent ductus arteriosus caused death. The mean age of murmur detection in those ventilated infants considered to have a patent ductus arteriosus was 6 days (range 2-19). Infants without a murmur or other features of a ductus arteriosus did not require to be ventilated beyond day 7 with the exception of the 2 fatalities already mentioned. Thus, relying on clinical criteria and particularly on the presence of a murmur, if sought often, rarely results in missing or seriously delaying the diagnosis of patent ductus arteriosus in babies with severe idiopathic respiratory distress syndrome.
Prostaglandin E1 is used to reopen the constricted ductus arteriosus in neonates with ductus-dependent circulation. To clarify possible prostanoid receptor agonists that can reopen the neonatal ductus with fewer side effects, we studied in vivo reopening of the neonatal ductus arteriosus by AE1-329, a prostanoid EP4-receptor agonist, in the rat. Neonatal rats were incubated at 33 degrees C. The inner diameter of the ductus was measured with a microscope and a micrometer following rapid whole-body freezing. Intraesophageal pressure was measured with a Millar micro-tip transducer. The ductus arteriosus constricted quickly after birth, and the inner diameter was 0.80 and 0.08 mm at 0 and 60 min after birth. PGE1 and AE1-329, injected subcutaneously at 60 min after birth, dilated the ductus dose-dependently. Thirty minutes after injection of 10 ng/g of PGE1 and AE1-329, the ductus diameter was 0.52 and 0.65 mm, respectively. The ductus-dilating effect of PGE1 was maximal at 15-30 min, and disappeared at 2 h. The ductus-dilating effect of AE1-329 was prolonged, the ductus was widely open at 6 h, and closed at 12 h after injection of 10 ng/g AE1-329. AE1-259-01 (EP2 agonist) (100 ng/g) did not dilate the neonatal ductus. Respiration was depressed by PGE1, but not by AE1-329. These results indicate the major role of EP4 in the neonatal ductus and that AE1-329, an EP4 agonist, can be used to dilate the neonatal constricted ductus without the side effects shown by EP3, including apnea.
Normal fetal circulation requires patency of the ductus arteriosus. Prenatal ductal closure causes profound circulatory changes, such as massive tricuspid regurgitation. After delivery, the clinical picture of these severely distressed cyanotic newborns usually improves rapidly as the circulation is no longer dependent on ductal patency after onset of respiration. This case report deals with a newborn infant with severe tricuspid regurgitation and a large atrial right to left shunt who was treated with prostaglandin E1 infusion at 12 hours of age and in whom cardiac angiography revealed no evidence of either patent or functionally closed ductus arteriosus and no anatomic cardiac abnormalities at 30 hours of age. On the basis of physiologic and morphologic observations in this infant, the possible role of premature ductal narrowing or closure in the pathogenesis of transient neonatal tricuspid regurgitation is discussed. It is recommended that documentation of ductal presence or absence should become part of the diagnostic evaluation of newborns with transient tricuspid regurgitation.
OBJECTIVE - To report the results of percutaneous occlusion of persistent ductus arteriosus with the Amplatzer prosthesis in 2 Brazilian cardiological centers. METHODS - From May 1998 to July 2000, 33 patients with clinical and laboratory diagnosis of persistent ductus arteriosus underwent attempts at percutaneous implantation of the Amplatzer prosthesis. The median age was 36 months (from 6 months to 38 years), and the median weight was 14kg (from 6 to 92kg). Sixteen patients (48.5%) were under 2 years of age at the time of the procedure. All patients were followed up with periodical clinical and echocardiographic evaluations to assess the presence and degree of residual shunt and possible complications, such as pseudocoarctation of the aorta and left pulmonary artery stenosis. RESULTS - The minimum diameter of the arterial ducts ranged from 2.5 to 7.0mm (mean of 4.0+/-1.0, median of 3.9). The rate of success for implantation of the prosthesis was 100%. Femoral pulse was lost in 1 patient. The echocardiogram revealed total closure prior to hospital discharge in 30 patients, and in the follow-up visit 3 months later in the 3 remaining patients. The mean follow-up duration was 6.4+/-3.4 months. All patients were clinically well, asymptomatic, and did not need medication. No patient had narrowing of the left pulmonary artery or of the aorta. No early or late embolic events occurred, nor did infectious endarteritis. A new hospital admission was not required for any patient. CONCLUSION - The Amplatzer prosthesis for persistent ductus arteriosus is safe and highly effective for occlusion of ductus arteriosus of varied diameters, including large ones in small symptomatic infants.
PURPOSE: To determine the prevalence of residual left-to-right shunt in patients submitted to closure of patent ductus arteriosus with use of Rashkind double-disc ductal occluding device, analyzing predictive factors that determine short and long-term prevalence of residual shunt. METHODS: Thirteen patients were submitted to percutaneous closure of patent ductus arteriosus with use of Rashkind double-disc device. Ten patients were male with mean age of 5.7 years. A 12mm diameter device was used in 7 cases and a 17mm device in the remaining six patients. All patients had clinical, radiological and echocardiographic follow up, after 24h, 1 month, 6 months and one year after the procedure. Morphology and length of the ductus arteriosus and the presence of residual shunt after 15 min, 24h and one year after the procedure, were correlated. RESULTS: In one case, embolization of the device to the pulmonary artery determined the in success of the procedure. Residual shunt was present in 75% of the patients after 15 min of the procedure, in 33.3% after 24h, in 25% after 1 month and 6 months and in 16.6% after 1 year. The most important and isolated predictive factor leading to a high prevalence of residual shunt after 24h and after 1 year of the procedure was the presence of ductus arteriosus diameter > or = 4.5mm at the site of its insertion in the pulmonary artery. CONCLUSION: Prevalence of residual left-to-right shunt decreases over the time, with a low incidence after one year follow-up. A higher incidence of residual shunt at 24h and 1 year after the procedure occurred in the cases where the diameter of the ductus arteriosus was > or = 4.5mm, at the site of its insertion in the pulmonary artery.
A case of successfully operated neonatal ductus arteriosus aneurysm is described. Cardiac catheterization was performed to confirm the diagnosis because of a misinterpretation of the anatomy on transthoracic echocardiography. Rupture, embolism and infection are described complications of such aneurysms. Surgery should therefore be recommended without delay.
The incidence of persistent patency of the ductus arteriosus beyond the third day of life was prospectively determined in 100 preterm infants with birthweights of 2,000 gm or less and 50 infants with birthweights of 2,001 to 2,500 gm. The overall incidence was 21% and was inversely related to increasing gestational age and birthweight. The data suggest that immaturity is the major determinant of the persistent patency of the ductus arteriosus. Spontaneous delayed closure of the ductus occurred in 79% of patients that survived the immediate neonatal period. There was a high degree of association between the presence of a patent ductus arteriosus (PDA) and respiratory distress syndrome (RDS). Eight infants with severe RDS and PDA developed heart failure and four required surgical ligation of the ductus. None of the infants with birthweights greater than 2,000 gm who had PDA developed heart failure or required surgical ligation of the ductus arteriosus.