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PubMedDate not supplied

Detachable coils for occlusion of patent ductus arteriosus in 2 dogs.

OBJECTIVE: To describe the use of a detachable coil for transcatheter closure (TCC) of patent ductus arteriosus (PDA) in 2 dogs. STUDY DESIGN: Clinical study. ANIMALS: Two female Pembroke Welsh Corgi dogs with PDA. METHODS: Using fluoroscopic guidance, an 8-mm-diameter coil stent with 5 loops (detachable coils for PDA closure) was inserted via catheterization of the femoral artery. The catheter was passed through the PDA into the pulmonary artery. The coil was withdrawn so that 1.5 loops remained on the pulmonary side of the orifice of the ductus. The rest of the loops were pushed out from the catheter into the ductus. After confirming the correct placement of the coil and the effectiveness of the occlusion, the delivery wire was detached from the coil. RESULTS: Insertion of the coil was easily performed, even without previous experience. Immediate and marked decrease of the cardiac murmur was auscultated. Only slight residual flow was detected by angiography conducted 3 months' postoperatively. The dogs experienced quick and uneventful recovery after coil placement and required minimal postoperative care. Follow-up evaluation of the dogs showed no functional clinical signs of PDA, and no cardiac abnormalities were detected on electrocardiographic, phonocardiographic, and echocardiographic examination. In dog 1, the residual flow had disappeared on the color-flow Doppler echocardiographic examination at 18 months' postoperatively. CONCLUSION: TCC using a detachable coil was easy, safe, and effective in 2 dogs with PDA. The minimal residual shunting observed only by echocardiography seemed hemodynamically insignificant. CLINICAL RELEVANCE: This method can be used as an alternative to traditional surgical methods.

Animals↗
PubMedDate not supplied

Postoperative rupture of an aortic aneurysmal dilation associated with a patent ductus arteriosus in a dog.

OBJECTIVE: To describe an unusual case of fatal aortic aneurysm rupture after standard ligation of a left-to-right shunting patent ductus arteriosus (PDA) and review the literature concerning the causes of aneurysm and applicable medical physics of blood flow that may contribute to mural failure. STUDY DESIGN: Clinical case report. SAMPLE POPULATION: An 11-month-old female Brittany spaniel. RESULTS: A PDA was diagnosed in the dog after referral for a grade IV/IV cardiac murmur. Diagnostic tests performed included a minimum database, thoracic radiography, and echocardiography. Conventional surgical ligation of the PDA was performed. The postoperative recovery from anesthesia was uneventful. Approximately 5 hours after surgery, the dog vocalized once and collapsed. All resuscitative efforts failed. Necropsy showed a large, spiral rupture of the cranial and dorsal wall of the aorta that extended from the left subclavian artery to 2 cm distal to the PDA-aorta junction. No evidence of intramural, perianeurysmal hemorrhage or inflammation was noted. Histopathologic examination of the ruptured aneurysm showed that the wall lacked a defined tunica intima and endothelial cell layer. A distinct separation of the thinned tunica media parallel to the elastic fibers was noted. CONCLUSIONS AND CLINICAL RELEVANCE: Dilatation of the aorta near the area of a PDA is one of the recognized abnormalities associated with the condition. Aneurysmal dilatation results from and contributes to abnormal blood flow dynamics and increased aortic wall tension, which promotes expansion. Although an unusual and previously unreported sequela, rupture of the aneurysm should be considered a possible complication when ligation of a PDA with a conspicuous aortic aneurysmal dilation is performed.

Animals↗
PubMedDate not supplied

Comparison of the incidence of residual shunting between two surgical techniques used for ligation of patent ductus arteriosus in the dog.

OBJECTIVE: To compare the incidence of residual patent ductus arteriosus (PDA) flow after ligation using 2 different dissection techniques: a standard dissection and a method described by Jackson and Henderson. STUDY DESIGN: A randomized, prospective study. ANIMALS: Thirty-five dogs admitted for surgical correction of a left to right shunting PDA. METHODS: Dogs were randomly assigned: 19 to a standard dissection technique (group S) and 16 to the Jackson and Henderson dissection group (group JH). RESULTS: Gender ratio, age at surgery, and diameter of the ductus were not statistically different between groups. Breed distribution was also similar. Because 1 dog had fatal intraoperative hemorrhage, only 34 dogs were available for residual flow comparisons. Twenty-one percent of group S dogs had residual flow compared with 53% in group JH. Whereas no intraoperative complications occurred in group S, 3 were encountered in group JH. CONCLUSIONS: The incidence of residual flow was higher when the Jackson and Henderson dissection was used for PDA ligation compared with a standard method of dissection. This was probably because of entrapment of loose connective tissue within the medial aspect of the ligature, impeding complete closure of the ductus. CLINICAL RELEVANCE: Ideal PDA closure should result in no residual ductal flow to prevent possible adverse long-term sequelae, such as recanalization and infective endocarditis.

Animals↗
PubMedDate not supplied

Sodium nitroprusside-induced deliberate hypotension to facilitate patent ductus arteriosus ligation in dogs.

OBJECTIVE: To report the use of sodium nitroprusside to induce deliberate hypotension to reduce hemorrhage and facilitate surgical ligation of complicated patent ductus arteriosus (PDA) in dogs. STUDY DESIGN: Retrospective study. ANIMALS: Six dogs. METHODS: Hemorrhage occurred during surgical ligation of PDA in 5 dogs. Surgical dissection and isolation of the PDA were very difficult in a sixth dog that was considered to be at increased risk for ductus rupture. Sodium nitroprusside (5 to 25 microg/kg/min intravenously) was administered to these 6 dogs to induce hypotension to reduce blood loss and facilitate surgical ligation of the PDA. RESULTS: Sodium nitroprusside infusion reduced blood pressure (mean arterial pressure, 45 to 60 mm Hg) within 5 to 10 minutes and hemorrhage from the PDA, facilitating its surgical ligation. Recovery from surgery and anesthesia was uneventful in all 6 dogs. CONCLUSIONS: Sodium nitroprusside infusion can be used to induce deliberate hypotension in dogs to facilitate surgical ligation of PDA. CLINICAL RELEVANCE: Sodium nitroprusside infusion produces hypotension within 5 to 10 minutes and is easy to control, rapidly abates, and should help to facilitate surgical ligation of PDA.

Animals↗
PubMed2001

The treatment of patent ductus arteriosus in preterm infants. A review and overview of randomized trials.

Patent ductus arteriosus (PDA) is a common problem in very preterm infants. It results in a significant left-to-right shunt and an increase in left ventricular output. Pulmonary compliance can be reduced. Systemic effects result from the diastolic steal and retrograde diastolic blood flow. Randomized controlled trials of PDA closure fall into three groups: (i) prophylactic treatment in the first 24 h, (ii) pre-symptomatic treatment on ultrasound evidence of a PDA or the first clinical signs and (iii) treatment when it becomes haemodynamically significant. Prophylactic treatment with indomethacin reduces the incidence of intraventricular haemorrhage. All the trials have a decreased need to treat a subsequent PDA in the treatment group. There are no other improvements in outcome, without any change in mortality, bronchopulmonary dysplasia, necrotizing enterocolitis or retinopathy of prematurity. Clinical decisions on the treatment of the ductus should be individualized and based on the gestation of the baby, the respiratory condition and the size of the ductal shunt.

Anti-Inflammatory Agents, Non-Steroidal↗
PubMed2000

Low-dose continuous indomethacin in early days of age reduce the incidence of symptomatic patent ductus arteriosus without adverse effects.

We conducted a comparative study to evaluate whether the low-dose continuous indomethacin therapy in the early days of age would reduce incidence of the symptomatic patent ductus arteriosus (PDA) without the adverse effects. Thirty-seven infants were in the historical comparison group, and 39 infants were given low-dose indomethacin continuously (0.004 mg/kg/h) from 6-12 postnatal hours until the recognition of closing PDA. Low-dose continuous indomethacin significantly decreased the incidence of symptomatic PDA at 5 days of age (p < 0.01) as compared with the historical comparison group. There was no episode of decreasing urinary output and necrotizing enterocolitis in the indomethacin group. We conclude that the low-dose continuous indomethacin therapy results in decreasing the incidence of symptomatic PDA without significant adverse reactions.

Anti-Inflammatory Agents, Non-Steroidal↗
PubMed2003

Risk factors predicting vasopressor use after patent ductus arteriosus ligation.

Ligation of the patent ductus arteriosus (PDA) is sometimes complicated by postoperative hypotension requiring vasopressor(s). It is unclear which infants are at risk for this complication. We conducted a retrospective and prospective cohort study to identify risk factors predicting vasopressor use after PDA ligation. Our patients were infants < 37 weeks of gestation who underwent PDA ligation. The primary outcome was the use of vasopressor(s) within 72 hours after PDA ligation, defined as beginning vasopressor(s) or increasing the dose of vasopressor(s). Thirty-two of 100 (32%) study infants required vasopressor(s) after PDA ligation. Infants who had lower birth weights, lower gestational ages, higher ventilator support, or whose mothers had received antenatal steroids had a higher risk of vasopressor use. Infants who required vasopressor(s) were at increased risk of dying before 36 weeks postmenstrual age. Lower birth weight, lower gestational age, and higher respiratory support define a high-risk subgroup of patients in whom the prophylactic administration of vasopressor(s) could be studied.

Cohort Studies↗
PubMed2003

Feasibility of surgery for patent ductus arteriosus of premature babies in a neonatal intensive care unit.

Twenty-two premature neonates underwent surgical haemoclip closure of patent ductus arteriosus in a neonatal intensive care unit (NICU). Surgery was performed in the NICU in order to prevent hypothermia and interruption of care, and to avoid accidental vascular access removal and extubation. The results suggest that morbidity can be limited by performing the surgery in an NICU, and by switching from conventional to high-frequency mechanical ventilation in case of severe respiratory failure.

Ductus Arteriosus, Patent↗
PubMed2004

Indomethacin therapy for patent ductus arteriosus in premature infants: efficacy of a dosing strategy based on a second-dose peak plasma indomethacin level and estimated plasma indomethacin levels.

The objective of this study was to determine the rate of patent ductus arteriosus (PDA) closure in premature infants using an adjustable indomethacin (INDO) dosing strategy, based on a second-dose peak plasma INDO level. We conducted a retrospective review of the medical records of premature infants that were treated with INDO for a PDA, had a second dose peak plasma NDO levels, and followed predetermined guidelines for INDO dosing adjustments, over a 4-year period (1995 to 1998). Of 103 infants treated with the adjustable INDO dosing strategy, 66 (64%) achieved PDA closure whereas 37 (36%) did not. No differences in the second-dose peak plasma INDO levels (830 +/- 339 versus 702 +/- 381 ng/mL), day of life treatment was started (4 +/- 3 versus 4 +/- 2 days), or the number of doses of INDO received (4 +/- 1 versus 5 +/- 2 dose) were observed between responders and nonresponders. However, fourth-dose peak plasma INDO levels, which were available from 38 of 66 (57%) of the responders and 20 of 37 (54%) of the nonresponders, were lower in nonresponders (1553 +/- 413 versus 1829 +/- 609 ng/mL, p < 0.05). Patient demographics, including birth weight and gestational age, were similar between these groups. Using an adjustable INDO dosing strategy, based on a second-dose peak plasma INDO level and estimated plasma levels, PDA closure rates of 64% can be achieved. Although a clear relationship between INDO plasma levels and PDA closure was evident form this study, the rate of PDA closure in our study was lower than has been observed in studies with serial plasma INDO level monitoring.

Cardiovascular Agents↗
PubMed2004

Indomethacin-induced early patent ductus arteriosus closure cannot be predicted by a decrease in pulse pressure.

Wide pulse pressure is considered to be a sign of patent ductus arteriosus (PDA). We tested the hypothesis that, following indomethacin therapy, PDA closure is associated with a significant decrease in pulse pressure. Thirty-two ventilated preterm infants were echocardiographically diagnosed within the first 24 hours of life with PDA. Systolic, diastolic, and mean arterial blood pressures were measured prior to indomethacin treatment and after echocardiographically confirmed PDA closure. Following PDA closure, systolic and diastolic blood pressures and mean arterial pressure increased significantly without a significant change of pulse pressure (17 +/- 7 to 20 +/- 12 torr). We conclude that in preterm infants with PDA, systolic, diastolic, and mean arterial blood pressures increase significantly within first few days of life. Pulse pressure does not appear to be affected by early PDA closure. We speculate that high pulmonary resistance in the first days of life prevents significant diastolic aortic runoff and leaves pulse pressure unaffected by PDA, as well as by its closure.

Blood Pressure↗
PubMed1984

Effect of patent ductus arteriosus on lower extremity blood flow velocity patterns in preterm infants.

We used a 20-MHz, range-gated, pulsed Doppler device to measure noninvasively femoral artery blood flow velocity patterns in 24 preterm infants with patent ductus arteriosus (PDA). Mean spatial flow velocity and its temporal average were recorded by illumination of the entire flow stream. Peak systolic forward flow velocity (Vs), peak diastolic retrograde flow velocity (VD), mean flow velocity (Vf), and the peak to peak-mean velocity ratio, (VS-VD)/Vf, were determined serially in each patient. The changes in the femoral flow velocity pattern preceded or coincided with other evidence of ductal left to right shunting. Prior to PDA closure, (VS-VD)/Vf averaged 14.1 and Vf averaged 4.4 cm/sec; after ductal closure, (VS-VD)/Vf fell to 3.7 (P less than .001) and Vf rose to 9.1 cm/sec, more than twice the preclosure value (P less than .001). Large diastolic reverse flow velocity vectors and low mean velocity correlated with large left to right PDA shunts estimated from other methods of assessment. The noninvasive femoral artery Doppler approach detects patency of the ductus early in life, reflects left to right shunting in diastole, and emphasizes the impact of the PDA on systemic blood flow.

Blood Flow Velocity↗
PubMedDate not supplied

[Trans-catheter closure of patent ductus arteriosus in childhood--an alternative to surgical ligature].

Transcatheter closure of a persistently patent ductus arteriosus (PDA) was successfully performed in four children using a Rashkind double disk umbrella device. Mean age was 5.1 +/- 1.5 (2.8 to 6.3 years) and weight 18.8 +/- 3.8 kg (14.1 to 22.3 kg). In all children the PDA was the only cardiac lesion and was diagnosed clinically and by means of continuous wave and color-coded doppler echocardiography. After angiographic measurement of PDA size the correlating device was implanted. The ductus was closed immediately in two children, whereas there was a residual angiographic shunt in the others. Echocardiography performed within 24 hours showed a minimal shunt only in one of these cases. The shunt had disappeared at the one month follow up study. We experienced none of the reported possible complications. Transcatheter closure of the PDA after the neonatal period seems to be a safe and effective alternative to surgical ligation as our early experience shows, and should become the procedure of first choice in these patients.

Angiocardiography↗
PubMed1990

Hemodynamic changes in a term newborn piglet model of patent ductus arteriosus.

Patent ductus arteriosus (PDA) is a common form of congenital heart disease in full-term infants. To investigate the morbidities associated with a left to right PDA shunt, we produced a PDA in six full-term newborn piglets (less than 36 hours old) by bathing the ductus arteriosus with prostaglandin E (PGE) and infiltrating it with formalin. In five age-matched piglets, the ductus arteriosus was ligated to serve as controls. Microsphere determinations of left ventricular output (LVO) and regional blood flow (Q) were made on three consecutive days. We produced left to right shunts of 36 to 47% (mean) in the experimental piglets. The experimental piglets had a 22 to 36% increase in LVO with a one- to twofold reduction in percentage of LVO to the kidneys and carcass (p less than 0.05). Although percentage of LVO to the gastrointestinal tract was reduced (p less than 0.05), no reduction of absolute Q to the gastrointestinal tract was observed. Brain and heart Q were similar in both groups. We conclude that significant hemodynamic changes result from left to right shunting in the full-term newborn piglet with PDA. These hemodynamic changes, such as reduction in renal blood flow, are relevant information that will help explain the morbidities observed in infants with a hemodynamically significant PDA with a left to right shunt.

Animals↗
PubMedDate not supplied

[Doppler sonographic flow parameter of the anterior cerebral artery in patent ductus arteriosus of the newborn infant compared to a healthy control sample].

33 premature infants (age: 32 +/- 3 weeks; birth weight 1,268 +/- 535 gs) with the clinical signs of patent ductus arteriosus Botalli (PDA) and a control group of 96 healthy infants (age: 37 +/- 4 weeks; birth weight 2 348 +/- 944 gs) were investigated. Pulsed doppler recordings were obtained in the anterior cerebral arteries (ACA) and compared with the flow pattern in the truncus coeliacus (TC). In all children the maximal systolic velocity (Vs), the endsystolic (Ves) and the enddiastolic velocity (Ved) and the pulsatility-index (PI) were measured. The 96 healthy premature born infants showed the following velocities: Vs: 41 +/- 12 cm X sec-1; Ves: 19 +/- 7 cm X sec-1; Ved: 10 +/- 4 cm X sec-1. The pulsatility-index was 0.74 +/- 0.08. In children with PDA all velocities were significantly lower than in the healthy control group: Vs: 31 +/- 10 cm X sec-1; Ves: 7 +/- 6 cm X sec-1; Ved: -1 +/- 5 cm X sec-1. Ved was more decreased than Vs resulting in a significant increase in PI (1.04 +/- 0.14). 22 infants with surgically proven large PDA (age: 31 +/- 3 weeks; birth weight: 1,160 +/- 467 gs) showed significant lower velocities (Vs: 34 +/- 8 cm X sec-1; Ves: 4 +/- 4 cm X sec-1; Ved: -4 +/- 4 cm X sec-1) in comparison with the healthy control group and the 11 children with small PDA (age: 33 +/- 4 weeks; birth weight: 1,494 +/- 621 gs).(ABSTRACT TRUNCATED AT 250 WORDS)

Birth Weight↗
PubMed1981

[Haemodynamics of blood supply to the pulmonary or body circulation via a patent ductus arteriosus in infants (author's transl)].

To control the cardiopulmonary functioning of high risk newborn with congenital heart defects the authors apply computergenerated recording of vital parameters predominantly measured by non-invasive methods. It was found that periodic variations of the arterial partial oxygen pressure occur with occlusion of the outflow from both the right and the left ventricle, associated with patent ductus arteriosus. The authors interpret these periodic variations as intermittent contractions of the arterial duct. The pathophysiology of this phenomenon is discussed.

Blood Circulation↗
PubMed1982

Prophylactic indomethacin therapy for patent ductus arteriosus in very-low-birth-weight infants.

We performed a double-blind, controlled study of prophylactic indomethacin therapy in 47 premature infants (less than 1700 g) who had subclinical patent ductus arteriosus. They received either indomethacin or placebo at a mean age of 2.9 days. Among the 25 infants weighing more than 1000 g, a hemodynamically important ductus shunt developed in only four of the 14 given placebo. The incidence of important shunts, the number of surgical ligations, and the duration of oxygen therapy were not appreciably different between the study groups. In contrast, among the 22 infants who weighed 1000 g or less, a major ductus shunt developed in 10 of the 12 given placebo. In the smaller infants indomethacin therapy was associated with a significantly lower incidence of major shunts, fewer surgical ligations, a decreased duration of oxygen therapy, and fewer days necessary to regain birth weight. We conclude that prophylactic indomethacin therapy in infants weighing under 1000 g prevents the later development of large ductus shunts and decreases morbidity.

Clinical Trials as Topic↗
PubMed2002

Early reopening and recanalization after successful coil occlusion of the patent ductus arteriosus.

BACKGROUND: Controversy exists regarding early reopening and recanalization after successful (complete) coil occlusion of the patent ductus arteriosus (PDA). METHODS: Patients with successful PDA coil occlusion were reviewed with regard to PDA size and type, coil size, number of coils, and delivery technique. Follow-up echocardiograms at <24 hours, 6 months, and >12 months were reviewed for residual PDA shunt, left pulmonary artery (LPA) stenosis, and aortic obstruction. RESULTS: Successful coil occlusion was achieved in 94 patients. On the initial (<24 hours) echocardiogram, 76 of 92 (83%) had complete PDA occlusion, 5 of 92 (5%) had mild LPA stenosis, and no patient had aortic obstruction. Follow-up at 6 months was available in 70 patients, 57 with complete occlusion on the initial echocardiogram. PDA reopening was found in 3 of 57 patients (5%). Larger PDA diameter was associated with residual shunt (2.40 +/- 0.40 mm versus 1.87 +/- 0.53 mm; P <.01). Disagreement between the initial and 6-month echocardiogram was found in 11 of 70 patients (16%). Intermediate follow-up (median, 30 months; range, 12 months to 5.3 years) was available in 46 patients, 38 with complete occlusion on the 6-month echocardiogram. No patient (0 of 38) with a normal echocardiogram at 6 months developed recanalization, LPA stenosis, or aortic obstruction. CONCLUSION: These data suggest that: (1) routine echocardiography immediately after PDA coil occlusion is unnecessary; (2) early PDA reopening is uncommon; and (3) PDA recanalization does not occur if complete echocardiographic closure is documented 6 months after coil occlusion. Additional follow-up examination in these patients may not be necessary.

Adolescent↗
PubMed2002

Quantification of left-to-right shunt in patent ductus arteriosus with the PISA method.

Direct Doppler echocardiographic calculation of shunt flow in patent ductus arteriosus (PDA) may be difficult because the orifice area is not well visualized. We used proximal isovelocity surface area (PISA) method to calculate the effective shunt orifice area and the shunt volume in a patient with PDA. The PISA calculation correlated well with shunt estimation by echocardiographic volumetric methods and by oximetry.

Adult↗