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At least 1,243 records · Page 69Linked to original sources
PubMed2004

Multicenter USA Amplatzer patent ductus arteriosus occlusion device trial: initial and one-year results.

OBJECTIVES: We sought to review and report initial and one-year efficacy and safety results of the multicenter USA Amplatzer ductal occluder (ADO) device trial. BACKGROUND: Transcatheter closure of a moderate to large patent ductus arteriosus (PDA) using conventional techniques is challenging. The ADO can close a PDA up to 12 mm in diameter. METHODS: From September 1999 to June 2002, 484 patients were enrolled in 25 U.S. centers. Forty-five (9%) of 484 patients did not have ADO implantation, because the PDA was too small or because of elevated pulmonary resistance. The median age of the patients at catheterization was 1.8 years (range 0.2 to 70.7 years), and weight was 11 kg (range 4.5 to 164.5 kg). RESULTS: The median PDA minimal diameter was 2.6 mm (range 0.9 to 11.2 mm); 76 (17%) of 439 were larger than 4.0 mm. Median pulmonary artery mean pressure was 20 mm Hg (range 7 to 80 mm Hg). The ADO was implanted successfully in 435 (99%) of 439 patients, with a median fluoroscopy time of 7.1 min (range 2.9 to 138.4 min). Angiographic demonstration of occlusion was seen in 329 (76%) of 435. This increased to 384 (89%) of 433 on post-catheterization day 1, with occlusion documented in 359 (99.7%) of 360 at one year. At the last evaluation in all patients at any time, PDA closure was documented in 428 (98%) of 435 patients. There have been two cases of partial left pulmonary artery occlusion after ADO implantation and no cases of significant aortic obstruction. CONCLUSIONS: Moderate to large PDAs can be effectively and safely closed using the ADO device, with excellent initial and one-year results. This device should obviate the need for multiple coils or surgical intervention for these defects.

Adolescent↗
PubMed2006

The influence of percutaneous closure of patent ductus arteriosus on left ventricular size and function: a prospective study using two- and three-dimensional echocardiography and measurements of serum natriuretic peptides.

OBJECTIVES: We aimed to evaluate the effect of percutaneous closure of patent ductus arteriosus (PDA) on left ventricular (LV) hemodynamics. BACKGROUND: Today, most PDAs are closed percutaneously. Little is known, however, about hemodynamic changes after the procedure. METHODS: Of 37 children (ages 0.6 to 10.6 years) taken to the catheterization laboratory for percutaneous PDA closure, the PDA was closed in 33. Left ventricular diastolic and systolic dimensions, volumes, and function were examined by two-dimensional (2D) and three-dimensional (3D) echocardiography and serum concentrations of natriuretic peptides measured before PDA closure, on the following day, and 6 months thereafter. Control subjects comprised 36 healthy children of comparable ages. RESULTS: At baseline, LV diastolic diameter measured >+2 SD in 5 of 33 patients. In 3D echocardiography, a median LV diastolic volume measured 54.0 ml/m2 in the control subjects and 58.4 ml/m2 (p < 0.05) in the PDA group before closure and 57.2 ml/m2 (p = NS) 6 months after closure. A median N-terminal brain natriuretic peptide (pro-BNP) concentration measured 72 ng/l in the control group and 141 ng/l in the PDA group before closure (p = 0.001) and 78.5 ng/l (p = NS) 6 months after closure. Patients differed from control subjects in indices of LV systolic and diastolic function at baseline. By the end of follow-up, all these differences had disappeared. Even in the subgroup of patients with normal-sized LV at baseline, the LV diastolic volume decreased significantly during follow-up. CONCLUSIONS: Changes in LV volume and function caused by PDA disappear by 6 months after percutaneous closure. Even the children with normal-sized LV benefit from the procedure.

Child↗
PubMed2006

Determination of indomethacin in plasma by micellar electrokinetic chromatography with UV detection for premature infants with patent ducts arteriosus.

A simple and selective micellar electrokinetic chromatography (MEKC) is described for determination of indomethacin in plasma. Plasma proteins are precipitated by acetonitrile. An aliquot of supernatant was evaporated and reconstituted with Tris buffer for MEKC analysis. The separation of indomethacin was performed at 25 degrees C using a background electrolyte consisting of Tris buffer (30 mM; pH 8.0) with 100 mM sodium octanesulfonate (SOS) as an anionic surfactant. Under this condition, a good separation with high efficiency and short analysis time is achieved. Several parameters affecting the separation of indomethacin were studied, including pH and concentrations of the Tris buffer and SOS. The linear range of the method for the determination of indomethacin was over 0.3-10.0 microg/mL; the detection limit (signal-to-noise ratio=3; injection 0.5 psi 5s) was 0.1 microg/mL. The proposed method for determination of indomethacin in premature infants with patent ducts arteriosus has been demonstrated.

Administration, Oral↗
PubMed2005

A rapid and sensitive microscale HPLC method for the determination of indomethacin in plasma of premature neonates with patent ductus arteriousus.

Indomethacin (IND) is the drug of choice for the closure of a patent ductus arteriosus (PDA) in neonates. This paper describes a simple, sensitive, accurate and precise microscale HPLC method suitable for the analysis of IND in plasma of premature neonates. Samples were prepared by plasma protein precipitation with acetonitrile containing the methyl ester of IND as the internal standard (IS). Chromatography was performed on a Hypersil C(18) column. The mobile phase of methanol, water and orthophosphoric acid (70:29.5:0.5, v/v, respectively), was delivered at 1.5 mL/min and monitored at 270 nm. IND and the IS were eluted at 2.9 and 4.3 min, respectively. Calibrations were linear (r>0.999) from 25 to 2500 microg/L. The inter- and intra-day assay imprecision was less than 4.3 % at 400-2000 microg/L, and less than 22.1% at 35 microg/L. Inaccuracy ranged from -6.0% to +1.0% from 35 to 2000 microg/L. The absolute recovery of IND over this range was 93.0-113.3%. The IS was stable for at least 36 h when added to plasma at ambient temperature. This method is suitable for pharmacokinetic studies of IND and has potential for monitoring therapy in infants with PDA when a target therapeutic range for IND has been validated.

Anti-Inflammatory Agents, Non-Steroidal↗
PubMed2005

The use of a bedside assay for plasma B-type natriuretic peptide as a biomarker in the management of patent ductus arteriosus in premature neonates.

OBJECTIVE: To test the utility of the bedside plasma concentration of B-type natriuretic peptide (BNP) assay as a screen for patent ductus arteriosus (PDA) in premature neonates. STUDY DESIGN: Newborn infants admitted to the neonatal intensive care unit (NICU) had paired echocardiography and BNP measurements at enrollment and every 4 to 5 days. RESULTS: Twenty neonates (gestational age approximately 28.6 weeks and birth weight approximately 1161 g) had 81 paired echocardiography and BNP determinations. BNP ranged from 5 to 3900 pg/mL. Fifty-six of 81 echocardiograms showed PDA. Significant correlations were found between BNP and ductal size and degree of shunting. Correlation was greater in infants >2 days of age. BNP >300 pg/mL predicted significant PDA, whereas BNP <105 pg/mL predicted absence of significant PDA. CONCLUSION: Bedside measurement of BNP correlates with magnitude of PDA in premature newborns, particularly beyond day 2, and may be useful in guiding diagnostic and management strategies.

Biomarkers↗
PubMed2006

Noninvasive diagnosis of aortic coarctation in neonates with patent ductus arteriosus.

OBJECTIVES: To find a noninvasive method to detect coarctation of the aorta (CoA) in the presence of a patent ductus arteriosus (PDA) in neonates. STUDY DESIGN: From 1994 to 1998, 36 neonates with CoA and PDA confirmed by surgery or cardiac catheterization were studied; another 19 neonates with isolated PDA served as control patients. The prospective study was conducted from 2001 to 2002 on 162 neonates. RESULTS: Among the 36 neonates in the CoA group, 14 patients (39%) had blood pressure discrepancy, 26 patients (72%) had a visualized posterior shelf by echocardiogram, and the ratio of isthmus/descending aorta diameters (I/D ratio) was below 0.64 in 32 patients (89%). None of the control patients had these features. A diagnostic approach was subsequently proposed, according to which a neonate with PDA who fulfilled any of the above features was diagnosed as CoA plus PDA. In the prospective study, the sensitivity and positive predictive values of this method were both 91.7%, whereas the specificity and negative predictive values were both 99.3%. CONCLUSIONS: Echocardiographic measurements of I/D ratio along with the delineation of posterior shelf and a BP discrepancy can satisfactorily identify CoA in the presence of PDA in neonates.

Aorta↗
PubMed2006

Indomethacin prophylaxis, patent ductus arteriosus, and the risk of bronchopulmonary dysplasia: further analyses from the Trial of Indomethacin Prophylaxis in Preterms (TIPP).

OBJECTIVES: To determine the risk of bronchopulmonary dysplasia (BPD) in subgroups of infants with and without patent ductus arteriosus (PDA) who were randomized to indomethacin prophylaxis or placebo, and to examine whether adverse drug effects on edema formation and oxygenation may explain why indomethacin prophylaxis does not reduce BPD. STUDY DESIGN: We studied 999 extremely low birth weight infants who participated in the Trial of Indomethacin Prophylaxis in Preterms (TIPP) and who survived to a postmenstrual age of 36 weeks. RESULTS: The incidence of BPD in the 2 subgroups of infants with PDA was 52% (55/105) after indomethacin prophylaxis and 56% (137/246) after placebo. In contrast, rates of BPD in the 2 subgroups without a PDA were 43% (170/391) after indomethacin prophylaxis and 30% (78/257) after placebo (P [interaction] = .015). Logistic regression analysis with adjustment for prognostic baseline factors showed that adverse and independent effects of indomethacin prophylaxis on the need for supplemental oxygen and on weight loss by the end of the first week of life may increase the risk of BPD in infants without PDA. CONCLUSIONS: Harmful side effects on oxygenation and edema formation may explain why indomethacin prophylaxis does not prevent BPD even though it reduces PDA.

Bronchopulmonary Dysplasia↗
PubMed2007

Patent ductus arteriosus ligation in premature infants: who really benefits, and at what cost?

PURPOSE: Patent ductus arteriosus (PDA) ligation in premature infants has been shown to have low surgical morbidity and mortality. Ligation goals include prompt improvement in cardiorespiratory failure, with rapid wean from mechanical ventilation; less risk of prolonged mechanical ventilation and subsequent chronic lung disease (CLD); and survival to discharge. This study was designed to examine true morbidity after ligation and elucidate which preoperative factors might predict favorable outcomes. METHODS: Institutional review board-approved retrospective review of 197 infants less than 38 weeks of gestational age (GA), undergoing PDA ligation via thoracotomy between January 1, 1992, and January 1, 2004. Chronic lung disease defined as need for supplemental oxygen at 36 weeks corrected GA. Student t and chi2 tests were used. RESULTS: Mean GA was 27 weeks (range, 23-35 weeks), birth weight was 957 g (range, 440-3170 g); infants underwent ligation at 16 days of life (range, 1-132 days). Duration of surgery was 50.5 minutes (range, 13-150 minutes). Mean postoperative times were 27 days to extubation, 60 days to wean from supplemental oxygen, and 84 days to discharge. Early extubation (within 10 days of ligation) occurred in only 54 patients (30%). Only 44 (22%) survived to discharge without CLD. Forty patients (20%) died, with respiratory failure the most common cause (70%). In general, early extubation, survival without CLD and survival to discharge were associated with greater GA and birth weight, higher Apgar scores, greater age and weight at surgery, no preoperative intraventricular hemorrhage, lack of ventilator dependence, and lower ventilator settings (P < .05). Preoperative amount and duration of indomethacin use, chest x-ray findings, and echocardiographic assessment of ductus size did not predict favorable outcomes (all P > .05). CONCLUSIONS: Most premature infants currently undergoing PDA ligation at our institution do not experience the anticipated rapid improvements in cardiorespiratory status and go on to develop CLD. Few preoperative variables (including radiographic and echocardiographic assessments) definitively predict outcomes.

Ductus Arteriosus, Patent↗
PubMed2006

A new theory of cryptogenic stroke and its relationship to patent foramen ovale; or, the puzzle of the missing extra risk.

Cryptogenic stroke (or stroke of undetermined cause) is a common cause of stroke and is statistically associated with patent foramen ovale (PFO). The largest study of cryptogenic stroke is the Homma study, which is a sub-study of the WARSS trial; it produced the following data: cryptogenic stroke patients with and without PFO, when treated with either aspirin or warfarin, all had identical recurrence rates. This is puzzling because it seems as though there ought to have been some extra risk in one of the two groups under one of the two treatments. How could everything come out the same? A review of the epidemiology of cryptogenic stroke shows that, compared to patients with stroke of determined cause, cryptogenic stroke patients are a little younger and have lower doses of the usual risk factors (hypertension and diabetes mellitus) but more PFO. Cryptogenic strokes appear to be embolic strokes from an unknown source. A previously published article setting forth a hypothetical theory of stress-induced stroke was used to analyze these data. It is suggested that stress can induce episodic systemic platelet activation and hypercoagulability, which causes transient thrombus formation and subsequent embolization on both the arterial and venous sides of the circulation; the latter requires a PFO to cause a stroke (paradoxical embolism). The sum of these two mechanisms explains cryptogenic stroke. The PFO subset of cryptogenic stroke includes patients with both early and late stage disease who have an aggregate risk approximately equal to that of patients without PFO. Cryptogenic stroke is part of the disease of stress-induced cerebrovascular disease. Aspirin and warfarin have already been shown to be equally effective in secondary prevention of ischemic stroke.

Adult↗
PubMed2005

In silico patent searching reveals a new cannabinoid receptor.

Increasing evidence suggests that some cannabinoids mediate their effects independently of the known cannabinoid CB(1) and CB(2) receptors. Two recently published patents indicate that several cannabinoid receptor ligands also bind to the orphan G-protein-coupled receptor GPR55. This receptor is reported to be expressed in several tissues and might function in lipid or vascular biology. Thus, GPR55 might represent a new cannabinoid receptor.

Amino Acid Sequence↗
PubMed2005

Use of sodium nitroprusside in the anaesthetic protocol of a patent ductus arteriosus ligation in a dog.

Patent ductus arteriosus (PDA) is one of the most common congenital cardiac abnormalities in the dog. Sodium nitroprusside has been proposed as an infusion during PDA ligation as the resultant nitric oxide production causes hypotension thereby facilitating surgical dissection and decreasing the risk of haemorrhage. This case report details how the method described did not decrease blood pressure and therefore had no beneficial effects. It is speculated that the lack of response may have been due to tachyphylaxis. Other drugs may be preferred to induce deliberate hypotension in the dog.

Anesthesia, General↗
PubMed2006

Original investigation of right-to-left shunting patent ductus arteriosus in an Irish setter puppy.

A six-month-old, entire female, Irish setter was presented with a two-month history of progressive hindlimb weakness and collapse on exercise. Thoracic auscultation revealed a soft systolic murmur and a split second heart sound. Differential cyanosis and polycythaemia were not observed. Right-to-left shunting patent ductus arteriosus (r-PDA) was confirmed on contrast echocardiography ("bubble study") and selective right ventricular angiography. Comparison of blood gases from the metatarsal and auricular artery confirmed the presence of differential hypoxia. This technique is not known to have been described previously in the diagnostic investigation of r-PDA in dogs.

Animals↗
PubMed2005

Cerebral hemodynamic change and intraventricular hemorrhage in very low birth weight infants with patent ductus arteriosus.

The aims of this study were to assess the hemodynamics of the cerebral arteries and intraventricular hemorrhage in very-low-birthweight (VLBW) infants with and without patent ductus arteriosus (PDA) by cranial Doppler sonography. VLBW infants with significant PDA were recruited into the study (sPDA) group. Arterial blood gas analysis and complete blood counts were done near the time of the cranial sonography examination. Mechanical ventilator settings and daily fluid intake were recorded. The cranial Doppler sonographic examinations were repeated after PDA closure by indomethacin therapy and/or surgical ligation. A total of 40 preterm infants fulfilled the criteria of the study group. Another 37 preterm infants were recruited into a control group. Mean birth weight and gestational age did not differ significantly between the two groups. Differences in heart rate, blood pH, pCO2, pO2, use of surfactant therapy, mean airway pressure, ventilation index and FiO2 were statistically significant. In the sPDA group before closure of the PDA, the left atrial diameter/aorta diameter ratio demonstrated a positive relationship with resistance index (RI) and an inverse relationship with end diastolic velocities (Vd). After closure of the PDA, these changes neared those of the control group. The overall incidence of intraventricular hemorrhage (IVH) was higher in the sPDA than in the control group. There was no statistical difference in the grading and severity of IVH between the two groups. However, all preterm infants with severe IVH were found in the sPDA group, and their RIs were all higher than 0.80. Cranial Doppler sonography can be a useful tool to evaluate cerebral hemodynamic changes in VLBW infants with sPDA. Increased RI and decreased Vd of the cerebral artery may indicate a probable sPDA, and normalization of the RI and Vd may suggest closure of the sPDA.

Anterior Cerebral Artery↗
PubMed2003

Vocal cord paralysis after transcatheter coil embolization of patent ductus arteriosus.

BACKGROUND: In patients with patent ductus arteriosus (PDA) after Gianturco coil embolization, vocal cord paralysis (VCP) had not been previously described. This study investigates the risk factors of coil embolization associated with VCP. METHODS: We reviewed the medical records of all patients who had undergone transcatheter closure of PDA with a Gianturco coil between March 1998 and May 2001, and 75 patients (age range, 6 months to 55 years; mean age, 5.5 years) were identified. The procedure was performed with local anesthesia and with sedation in some young children. No patient required general anesthesia or endotracheal intubation. RESULTS: Three of the 75 patients had hoarseness caused by VCP after coil embolization. Patients with VCP had a longer ductus length (P <.01) and a smaller ductus diameter (P <.01) than patients without VCP. The pathogenesis of VCP may be caused by tense stretching and angulation of the ductus arteriosus induced by the implanted coil, which leads to compression injury of the adjacent left recurrent laryngeal nerve. CONCLUSIONS: A long ductus length (> or =12 mm) and a small ductus diameter (<1 mm) are significant risk factors of VCP after coil embolization in children <1 year of age. We recommend that coil embolization be performed very carefully in patients with PDA.

Adolescent↗
PubMed1996

Effectiveness of a thermal shape-memory patent ductus arteriosus occlusion coil.

A new shape-memory coil for transcatheter closure of the PDA was developed and evaluated in a dog PDA model. The coil is sensitive to temperature (composed of thermal shape-memory nickel-titanium). The coil was delivered to and implanted in the PDA model with a 5F catheter through the femoral artery. The PDA model was made in 14 dogs by infrarenal aorta banding (diameter 2.0 +/- 0.6 mm; length 2.9 +/- 0.1 mm). Coils were implanted in 10 dogs, whereas the other 4 dogs served as controls. Complete occlusion of the PDA model was confirmed by angiography 24 hours after the coil implantation in 7 of 10 dogs, whereas small residual flow was noted even 2 weeks after the coil implantation in the other 3 dogs. The PDA model internal diameter in the dogs with complete occlusion (1.8 +/- 0.2 mm) was significantly smaller than the diameter in dogs with residual flow (2.9 +/- 0.4 mm, P < 0.05). In the 4 control dogs, the PDA model remained patent 2 weeks after the banding. We conclude that the transcatheter occlusion with the shape-memory coil was effective in the small-diameter PDA model.

Animals↗
PubMed1996

Transcatheter closure with single or multiple Gianturco coils of patent ductus arteriosus in infants weighing < or = 8 kg: retrograde versus antegrade approach.

Experience with transcatheter closure (TCC) of patent ductus arteriosus (PDA) in small infants is limited. Our goals were to evaluate the immediate and short-term results of TCC of PDA in small infants (< or = 8 kg) as attempted with single or multiple Gianturco coils and to compare results for PDA < or = 2.5 mm versus PDA > 2.5 mm. Twenty-four infants underwent an attempt at TCC of PDA at a median age of 0.7 years (range 2 weeks to 1.5 years) and median weight of 6.5 kg (range 2.3 to 8 kg). Coils were placed by the transvenous route in 14 patients and by the transarterial route in 10 patients. The median PDA diameter was 2.7 mm (range 0.4 to 5.2 mm). Ten patients had PDA diameters < 2.5 mm and all had complete closure, 9 with a single coil and 1 with two coils. Fourteen patients had PDA diameters > or = 2.5 mm; closure was complete in 10 patients, 9 of whom required multiple coils. There was a trend toward improved results with multiple coils delivered transvenously. There was immediate complete closure of the PDA with a diameter as large as 5.2 mm that persisted at a median follow-up period of 1.2 year. Closure was unsuccessful in 4 patients, each of whom required multiple coils. The median fluoroscopy time was 19 minutes. Complications included transient loss of femoral pulse in 2 infants, mild left pulmonary artery obstruction in 2, and nonretrievable coil migration to the right lung in one. We conclude that TCC is effective therapy for small infants with a PDA of diameter < or = 5.2 mm by the single-or multiple-coil technique on an outpatient basis and that TCC can be performed in neonates as small as 2.3 kg.

Cardiac Catheterization↗
PubMed1996

Transcatheter closure of the patent ductus arteriosus: comparison between the Rashkind occluder device and the anterograde Gianturco coils technique.

Thirty-five patients (mean age 43.7 months, mean weight 13 kg) underwent anterograde patent ductus arteriosus (PDA) occlusion with Gianturco coils (coil group). These patients were compared with 35 age- and weight-matched patients who underwent closure of their PDA with the Rashkind umbrella device (device group). The mean PDA diameter at its narrowest point was 2.8 mm in the coil group and 2.7 mm in the device group. There was immediate closure angiographically in 20 (57%) of 35 in the coil group compared with 9 (26%) of 35 for the device group. Color flow mapping before discharge revealed complete closure in 30 (86%) of 35 in the coil group compared with 18 (51%) of 35 in the device group (chi square = 9.5455, p < 0.005). Mean fluoroscopy time was 18.5 minutes (median 13.5 minutes) and 14.7 minutes (median 13 minutes) for the coil and device, respectively. Four coils and one device embolized down the pulmonary artery; all were successfully retrieved in the catheterization lab. Coil closure of the small to moderate PDA is safe and effective. It is more effective in achieving immediate closure than the Rashkind device. More clinical trials with the coil technique are warranted to establish the long-term results of this technique.

Cardiac Catheterization↗
PubMed1997

Coil occlusion of patent ductus arteriosus with detachable coils.

Twenty-five patients (mean age 7.0 +/- 4.8 years) underwent transcatheter coil occlusion of patent ductus arteriosus with detachable coils. The minimum diameter of the ductus arteriosus ranged from 1.0 to 4.2 mm (mean 2.6 +/- 0.9 mm). A single-coil technique was used in 17 patients, double- (six patients) or triple-coil (two patients) techniques were used in eight patients. The coil was not detached until sufficient shape and position of implanted coils were confirmed. All patients had successful implantation of coils regardless of the morphologic characteristics of the ductus. Immediately after the occlusion, heart murmurs were abolished in all patients. Color-flow mapping showed complete closure in 16 (64%) patients immediately after and 20 (80%) patients 1 month after the procedure. No significant complications occurred. The advantages of this detachable coil system may reduce coil migration and allow safer and more reliable execution of this procedure.

Adolescent↗