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PubMed1985

Left recurrent laryngeal nerve palsy associated with primary pulmonary hypertension and patent ductus arteriosus.

Two patients with left recurrent laryngeal nerve paralysis in association with pulmonary artery hypertension are described. One had primary pulmonary hypertension and the other had patent ductus arteriosus. The greatly dilated pulmonary artery in these patients resulted in compression of the left recurrent laryngeal nerve and produced a cardiovocal (Ortner's) syndrome. The pathogenesis of the vocal cord palsy was documented by cross-sectional computed tomography. In conclusion, computed tomography is of great help in differentiating this syndrome from other diseases such as mediastinal mass or lymphadenopathy whenever hoarseness is complicated by pulmonary hypertension.

Adult↗
PubMed1997

Evaluation of Gianturco coils for closure of large (> or = 3.5 mm) patent ductus arteriosus.

OBJECTIVES: This report evaluates the use of Gianturco coils to close large patent ductus arteriosus (PDAs) (> or = 3.5 mm) and describes transvenous delivery of 0.052-in. (0.132-cm) Gianturco coils. BACKGROUND: Coil closure of PDAs has become increasingly popular. However, the technique has significant limitations when used to close large PDAs. This report evaluates patient characteristics, PDA anatomy, hemodynamic variables, delivery technique and coil geometry to determine predictors of success. METHODS: Between January 1995 and January 1997, 16 of 118 patients undergoing catheterization for PDA closure were found to have large PDAs. Their median age and weight were 14 months (range 3 months to 43 years) and 8.5 kg (range 3.5 to 73), respectively. The mean PDA diameter was 4.3 mm (range 3.5 to 5.9). Closure of PDAs was attempted using transcatheter delivery of 0.038-in. (0.096-cm) and 0.052-in. coils. Differences in clinical, anatomic, hemodynamic and technical variables between successes and failures were compared. RESULTS: Eleven (69%) of 16 patients had successful closure of their PDA. Failures occurred only in patients < 8 months of age with an indexed PDA diameter > 7 mm/m and a pulmonary/systemic flow ratio > or = 2.8:1. Use of 0.052-in. coils tended to reduce the incidence of embolization and the number of coils needed for closure. CONCLUSIONS: Patients > 8 months of age can have successful closure of large PDAs with currently available Gianturco coils. The 0.052-in. Gianturco coils can be used safely to close large PDAs in infants as small as 6 kg. Increased experience and improved coil design may improve closure rates of large PDAs in infants.

Cardiac Catheterization↗
PubMed1998

Reopening after successful coil occlusion for patent ductus arteriosus.

OBJECTIVES: This study was performed to determine the frequency of patent ductus arteriosus (PDA) reopening and the factors that may predict reopening after successful coil occlusion. BACKGROUND: Transcatheter coil occlusion is a widely used and accepted method to close a PDA. After documented successful coil occlusion, we found PDAs that reopened. We hypothesized that specific factors are involved in those that reopened. METHODS: All patients who underwent percutaneous transarterial PDA coil occlusion were studied. Successful coil occlusion was documented. PDA reopening was determined when Doppler-echocardiography (DE) performed after the procedure was negative for PDA flow but at follow-up demonstrated PDA shunting. Patients with a reopened PDA were compared with all other patients in evaluating independent variables. RESULTS: Coil occlusion for PDA was attempted in 22 patients. Clinical success was achieved in 20 patients (91%), and DE was negative for PDA shunting in 19 patients (90%). At follow-up, five patients demonstrated reopening. The PDA minimal diameter was 1.4 +/- 0.5 mm (mean +/- SD) for the reopened group and 1.2 +/- 0.7 mm for the other patients. The PDA length was 2.9 +/- 1.9 mm for the reopened group and 7.1 +/- 3.2 mm for all other patients. All those with type B PDA were in the reopened group. When independent variables were compared between groups, only PDA length and type B PDA predicted reopening (p < 0.05). CONCLUSIONS: PDA reopening may occur after successful coil occlusion. Short PDA length and type B PDA are associated with reopening. The data suggest that in such anatomy, alternative strategies to the current coil occlusion technique should be considered.

Adolescent↗
PubMed1998

Catheter closure of moderate- to large-sized patent ductus arteriosus using the new Amplatzer duct occluder: immediate and short-term results.

OBJECTIVES: The aim of this study was to assess the immediate and short-term results of anterograde catheter closure of a moderate- to large-sized patent ductus arteriosus (PDA) using the new self-expandable, respositionable Amplatzer duct occluder (ADO) device. BACKGROUND: Transcatheter closure of a PDA using devices or coils is technically challenging and may be accompanied by a 38% incidence of residual shunts. METHODS: Twenty-four patients (6 male, 18 female) underwent attempted transcatheter closure of a PDA using the ADO at a median age of 3.8 years (range 0.4 to 48) and a median weight of 15.5 kg (range 6 to 70). The mean PDA diameter at its narrowest segment was 3.7+/-1.5 mm. A 6F long sheath was used for delivery of the ADO. Follow-up evaluation was performed with color flow mapping of the main pulmonary artery within 24 h and at 1 and 3 months after closure. RESULTS: Twenty three of the 24 patients had successful device placement. Angiography showed that 7 patients had complete immediate closure, 14 had a trace shunt (foaming through the device with no jet), and 2 had a small residual shunt (with a jet). Within 24 h, color Doppler revealed complete closure in all patients. The unsuccessful attempt was during an initial trial with a prototype that has been modified. The median fluoroscopy time was 13.5 min (range 6.3 to 47). All patients were discharged home the next day. There were no complications. Of the 23 patients, 21 completed the 1-month follow-up, all (95% confidence interval [CI] 86% to 100%) with complete closure, and 18 of 23 patients completed the 3-month follow-up, also all (95% CI 83% to 100%) with complete closure. CONCLUSIONS: Anterograde transcatheter closure using the new ADO is an effective therapy for patients with a PDA diameter up to 6 mm. Further clinical trials are underway.

Alloys↗
PubMed1998

Double-helix coil for occlusion of large patent ductus arteriosus: evaluation in a chronic lamb model.

OBJECTIVES: We sought to evaluate the efficacy and tissue reaction of a new miniature interventional device for occlusion of large patent ductus arteriosus (PDA) in a neonatal lamb model. BACKGROUND: A variety of devices are used to close PDAs by interventional measures. Spring coils found to have a high cumulative occlusion rate have thus far been limited to smaller PDAs because of the physical limitation of grip forces. METHODS: Memory-shaped double-cone stainless steel coils with enhanced stiffness of the outer rings by a double-helix configuration were mounted on a titanium/nickel core wire. A snap-in mechanism attaches the coil to the delivery wire, allowing intravascular coil retrieval and repositioning. The system was placed through a 4F or 5F Teflon catheter. A chronic lamb model (n = 8) of PDA (>5 mm) was used in which ductus patency was secured by a protocol of repetitive angioplasty procedures. The animals were killed after 1 to 181 days, and the ductal region was examined by inspection as well as by light and electron microscopy. RESULTS: Placement of the coils within the PDA was possible in all lambs. Before final detachment, the coils were retrieved or repositioned, or both, up to 12 times. In all but one animal the ductus was closed within 6 days after the procedure. The coils caused no infections or aortic and pulmonary artery obstruction. Histologic and electron microscopic studies revealed endothelial coverage of the implants but no foreign body reaction or local or systemic inflammation or erosion of the implant. CONCLUSIONS: The device effectively closed large PDAs in our model and may overcome the previous limitations of coils. Clinical trials are indicated.

Angiography↗
PubMed1999

Follow-up results of transvenous occlusion of patent ductus arteriosus with the buttoned device.

OBJECTIVES: The purpose of this presentation is to document results of buttoned device (BD) occlusion of patent ductus arteriosus (PDA) in a large number of patients with particular emphasis on long-term follow-up in an attempt to provide evidence for feasibility, safety and effectiveness of this method of PDA closure. BACKGROUND: Immediate and short-term results of BD occlusion of PDA have been documented in a limited number of children. METHODS: During a six-year period ending August 1996, transcatheter BD closure of PDA was attempted in 284 patients, ages 0.3 to 92 years (median 7) under a protocol approved by the local institutional review boards and FDA with an investigational device exemption in U.S. cases. RESULTS: The PDAs measured 1 to 15 mm (median 4) at the narrowest diameter; 20 were larger than 8 mm and 10 larger than 10 mm. They were occluded with devices measuring from 15 to 35 mm delivered via 7F (N = 140) or 8F (N = 144) sheaths. Successful implantation of the device was accomplished in 278 (98%) of 284 patients. The Qp:Qs decreased from 1.8+/-0.6 (mean+/-SD) to 1.09+/-0.19 (p < 0.001). Effective occlusion defined as no (N = 167 [60%]) or trivial (N = 79 [28%]) residual shunt was achieved in 246 (88%) patients. All types of PDAs, irrespective of the shape (conical, tubular or short), size (small or large) or length (short or long) of the PDA and previously implanted Rashkind devices, could be occluded. Follow-up data, 1 to 60 months (median 24) after device implantation, were available in 234 (84%) patients. Seven (3%) patients required reintervention to treat residual shunt with (N = 2) or without (N = 5) hemolysis. Actuarial reintervention-free rates were 95% at 1 and 5 years. There was gradual reduction of actuarial residual shunts and were 40%, 28%, 21%, 14%, 11%, 10%, 6% and 0% respectively at 1 day, 1, 6, 12, 24, 36, 48 and 60 months after device implantation. Incorporation of folding plug over the button loop in 10 additional patients produced immediate and complete occlusion of PDA. CONCLUSIONS: This large multiinstitutional experience confirms the feasibility, safety and effectiveness of buttoned device closure of PDAs. All types of PDAs irrespective of the shape, length and diameter can be effectively occluded. Incorporation of folding plug over the button loop produces complete PDA occlusion at the time of device implantation.

Adolescent↗
PubMed1999

The snare-assisted technique for transcatheter coil occlusion of moderate to large patent ductus arteriosus: immediate and intermediate results.

OBJECTIVES: The purpose of this study was to evaluate the feasibility, safety and efficacy of using a snare-assisted technique to coil occlude the moderate to large size patent ductus arteriosus (PDA). BACKGROUND: Transcatheter occlusion of small PDAs using Gianturco coils is safe and effective. However, in larger size PDAs and/or those with short PDA length, the procedure still carries risks of coil embolization, incomplete occlusion and failure to implant the coil. METHODS: From January 1994 to June 1997, the records of 104 consecutive snare-assisted coil occlusions of moderate to large PDAs (minimum diameter >2.0 mm) were reviewed. Immediate and intermediate outcomes including complete and partial occlusion, failure to implant and complications were analyzed with respect to ductal type and size. RESULTS: Patient age ranged from 0.1 to 70.1 years (median 3.3 years). Minimum PDA diameter ranged from 2.1 to 6.8 mm (mean 3.0 +/- 0.9 mm). Angiographic types were A-62, B-13, C-6, D-14 and E-9. Using the snare-assisted technique, coil placement was successful in 104/104 patients (100%), irrespective of size or angiographic type. Immediate complete closure was observed in 73/104 (70.2%) and was related to smaller PDA size, but not to angiographic type. Complete closure was documented in 102/104 (98.1%) at 2- to 16-month follow-up. Successful closure was unrelated to PDA size or type. Coil embolization to the pulmonary artery occurred in 3/104 (2.9%) patients and was not related to PDA size or type. The need for multiple coils was found in 28/104 patients (26.9%), and was related to larger PDA size, but not to angiographic type. CONCLUSIONS: The snare-assisted delivery technique allows successful occlusion of moderate to large PDAs up to 6.8 mm, irrespective of angiographic type. This technique permits improved control and accuracy of coil placement, and facilitates delivery of multiple coils.

Adolescent↗
PubMed2000

Further experience with transcatheter closure of the patent ductus arteriosus using the Amplatzer duct occluder.

OBJECTIVE: The aim of this study was to report further experience with transcatheter closure of the patent ductus arteriosus (PDA) using the Amplatzer duct occluder (ADO). BACKGROUND: The design of previously used devices is not ideal for this purpose, and their use has been associated with several drawbacks, especially in large PDAs. METHODS: Forty-three patients, aged 0.3 to 33 years (mean 6.4+/-6.7 years), with a moderate to large, type A to E PDA, underwent attempted transcatheter closure using the ADO. The device is a plug-shaped repositionable occluder made of 0.004-in. nitinol wire mesh. It is delivered through a 5F to 6F long sheath. The mean PDA diameter (at the pulmonary end) was 3.9+/-1.2 mm (range 2.2 to 8 mm). All patients had color flow echocardiographic follow-up (6 to 24 months) at 24 h, 1 and 3 months after closure, and at 6-month intervals thereafter. RESULTS: The mean ADO diameter was 6.1+/-1.4 mm (range 4 to 10 mm). Complete angiographic closure was seen in 40 of 43 patients (93%; 95% confidence interval [CI] 85.4% to 100%). The remaining three patients had a trivial angiographic shunt through the ADO. At 24 h, color flow mapping revealed no shunt in all patients. A 9F long sheath was required for repositioning of a misplaced 8-mm device into the pulmonary artery. The mean fluoroscopy time was 7.9+/-1.6 min (range 4.6 to 12 min). There were no complications. No obstruction of the descending aorta or the pulmonary artery branches was noted on Doppler follow-up studies. Neither thromboembolization nor hemolysis or device failure was encountered. CONCLUSIONS: Transcatheter closure using the ADO is an effective and safe therapy for the majority of patients with patency of the arterial duct. Further studies are required to establish long-term results in a larger patient population.

Adolescent↗
PubMed1983

[Surgical ligation of patent ductus arteriosus in the very-low-birth-weight premature infant].

Three recent cases of surgical closure of ductus arteriosus in very low birth weight infants (less than 1 000 g) are reported. The indications of both surgical and pharmacological closure in very low birth weight premature infants are discussed. The necessity of an early closure of a patent ductus arteriosus is now admitted in the very premature infant, but the use of indomethacin in the first days of life is often impossible because of its side-effects. The use of adapted non-invasive monitoring devices during surgery allows a better control of anaesthesia.

Anesthesia, General↗
PubMed2003

Echocardiographic guidance for transcatheter coil occlusion of patent ductus arteriosus in the catheterization laboratory.

The objective of this study was to investigate the feasibility of transthoracic echocardiography as a guide to monitor the completeness of patent ductus arteriosus (PDA) occlusion immediately after coil implantation. In all, 52 patients who underwent Gianturco coil implantation for PDA occlusion were evaluated by transthoracic echocardiography within 15 minutes after the first coil implantation in the catheterization laboratory. According to Doppler echocardiographic findings, these patients were classified into 3 groups: group 1, complete occlusion without residual shunt; group 2, a residual PDA diameter < 1 mm and no continuous waveforms detected; and group 3, a residual PDA diameter >or= 1 mm or continuous waveforms. There were 34 patients in group 1, 10 patients in group 2, and 8 patients in group 3. In a 12-month follow-up the complete occlusion rate was 100%, 90%, and 87.5% in groups 1, 2, and 3, respectively. We conclude that immediate Doppler echocardiography is useful in assessing the status of residual PDA just after coil implantation. Residual shunt < 1 mm and lack of continuous waveform on Doppler scan indicate sufficient ductal closure of PDA.

Adolescent↗
PubMed2003

Echocardiographic predictors of failure in patients undergoing coil occlusion of patent ductus arteriosus.

In this study, we sought to determine whether the risk of failure of coil occlusion of patent ductus arteriosus (PDA) could be predicted on the basis of echocardiographic variables. The echocardiographic characteristics of patients in whom PDA coil occlusion failed were compared with those in whom the procedure was successful. A total of 5 variables were evaluated: PDA diameter (PDAd); indexed PDAd; PDA shape; left ventricular end-diastolic diameter; and the presence of flow reversal in the descending aorta. We found that 2 variables related to the size of the duct (PDAd and PDAd/body surface area), and 2 related to the magnitude of the shunt (left ventricular end-diastolic diameter and flow reversal) were positively associated with failure (P <.05). PDAd and flow reversal had the greater effect in each group and remained significant when they were put into a logistic regression model to predict failure (P =.004 and.053, respectively). In conclusion, echocardiographic variables can predict risk of failure in patients undergoing PDA coil occlusion.

Adolescent↗
PubMedDate not supplied

Patent ductus arteriosus in an infant with atrioventricular septal defect and pulmonary hypertension: diagnosis by transesophageal color flow echocardiography.

An infant with complete atrioventricular septal defect (atrioventricular canal) was examined by standard transthoracic two-dimensional pulsed Doppler and color Doppler echocardiography. No evidence of ductus arteriosus was present. Preoperative transesophageal echocardiography identified a patent ductus: the left-to-right shunt seen by color Doppler echocardiography was enhanced by pharmacologic maneuvers aimed at decreasing pulmonary vascular resistance and increasing systemic vascular resistance. Transesophageal echocardiography was found to be more sensitive than transthoracic echocardiography even in a small infant.

Ductus Arteriosus, Patent↗
PubMedDate not supplied

Diagnosis of patent ductus arteriosus by serendipity in the adult.

Seven patients with patent ductus arteriosus (PDA) were seen in our adult echocardiography laboratory. In five of seven patients the diagnosis was made on color Doppler when it was not suspected clinically. The diagnosis became apparent because of a turbulent retrograde jet seen on color Doppler in the main pulmonary artery. One of the patients had known congenital heart disease and heart surgery in the past, and the diagnosis of PDA was missed both on catheterization and in the operating room. PDA may be unsuspected in adult patients and may be missed by techniques other than color Doppler echocardiography. The striking findings on color Doppler may help to make this important diagnosis in such patients.

Adult↗
PubMed1999

Evidence of patent ductus arteriosus and right-to-left shunt by finger pulse oxymetry and Doppler signals of agitated saline in abdominal aorta.

The diagnosis of patent ductus arteriosus (PDA) with right-to-left shunt in the adult by using transthoracic echocardiography (TTE) is difficult because of limited windows. We report a case of a 23-year-old woman who was referred for treatment of primary pulmonary hypertension but was found to have a PDA with a right-to-left shunt. On examination she had asymmetric hypoxia of the upper extremities on finger pulse oxymetry. Transthoracic echocardiography revealed a large right atrium and no atrial or ventricular septal wall defects. The diagnosis of PDA with Eisenmenger's syndrome was made after evidence of a right-to-left shunt was confirmed by Doppler signals of intravenous agitated saline in the abdominal aorta. This case illustrates the utility of Doppler signals from agitated saline in the abdominal aorta and finger pulse oxymetry, in addition to physical examination, in the diagnosis of PDA with right-to-left shunt.

Adult↗
PubMed2006

Outcome of percutaneous transarterial coil occlusion in patients with isolated patent ductus arteriosus using an upstream-and-push maneuver.

BACKGROUND: There are limited data on the outcome of percutaneous transarterial coil occlusion for isolated patent ductus arteriosus (PDA) in Taiwan. This study evaluated the 2-year outcome of 52 patients with isolated PDA who received percutaneous transarterial coil occlusion by an upstream-and-push maneuver. METHODS: From July 1997 to June 2002, a total of 52 patients (25 infants, 27 children) underwent occlusion of PDA with standard Gianturco coils. There were 39 females and 13 males. Patient age ranged between 7 days and 14 years, and weight was between 3 and 45 kg. Percutaneous transarterial coil occlusion was performed by an upstream-and-push maneuver. Chest auscultations, chest radiographs, and Doppler echocardiography were performed in all patients within 24 hours, and 1, 3, 6, 12 and 24 months after coil occlusion. RESULTS: Mean PDA diameter at the pulmonary end was 2.34 +/- 1.00 mm (range, 1.00-4.80 mm). Angiographic classification was megaphone type in 32 patients, window type in seven, tubular type in six, aneurysmal type in three, and elongated conical type in four. Complete PDA occlusion was performed with a single coil in 41 (79%) patients and with multiple coils in 11 (21%). The mean ratio of pulmonary to systemic blood flow was 1.95 +/- 0.95 (range, 1.10-5.80) before the procedure, and 1.02 +/- 0.04 (range, 1.00-1.20) after the procedure (p < 0.001). Immediate occlusion of the ductus was achieved 15 minutes after the procedure in 44 (85%) patients. Occlusion was achieved in 92% of patients within 24 hours and in 100% of patients by the 1-month follow-up. Follow-up at 24 months after the procedure revealed no complications. CONCLUSION: Percutaneous transarterial coil occlusion with 5-loop Gianturco coils can be effectively and safely achieved in patients with a PDA minimum diameter < 5 mm.

Cardiac Surgical Procedures↗
PubMed2002

New thinking on gene patents.

With the number of patent claims including DNA sequence booming, is there a way forward to help resolve disagreements over the many issues involved? One ethical body believes that there is and has produced a new study.

DNA↗
PubMedDate not supplied

Experimental evaluation of a new self-expanding patent ductus arteriosus occluder in a canine model.

PURPOSE: A new self-expanding patent ductus arteriosus (PDA) occluder was designed. MATERIALS AND METHODS: Percutaneous closure of surgically created aortopulmonary shunts was attempted in 19 dogs. The occlusion device consisted of a nitinol wire frame tightly woven into a cylinder with a flat retention disc. A polyester-filled frame was used in the last six procedures. A 6-F introducing sheath was advanced across the aortopulmonary conduit into the descending thoracic aorta. The prosthesis (attached on a stiff delivery cable) was advanced through the introducing sheath. The retention disc was first released in the descending thoracic aorta, then the cylindrical device frame was expanded within the conduit by withdrawing the sheath. RESULTS: Subtotal misplacement into the descending aorta occurred in one procedure (overall technical success rate, 95%), and one animal died before the 1-week follow-up. Complete angiographic shunt closure was achieved in seven of 18 (39%) animals at 30 minutes, 12 of 17 (71%) animals at 1 week, 14 of 17 (82%) animals at 1 month, and 11 of 12 (92%) animals at 3 months. Significantly higher 30-minute closure rates occurred with polyester-filled occluders compared with nonfilled occluders (five of five [100%] vs one of 13 [15%]; P = .002). Persistent shunt at 3 months occurred in only one nonfilled device (6%). In the remaining 16 animals, both orifices of the shunt were covered by a smooth glistening neoendothelium at postmortem examination. CONCLUSION: This device combines the advantages of small delivery system, easy placement, self-centering, and repositionability. Immediate shunt closure can be reliably accomplished with the polyester-filled prosthesis.

Alloys↗
PubMed2003

Treatment of patent ductus arteriosus.

Patent ductus arteriosus (PDA) continues to be one of the most common problems found in premature infants. The incidence is inversely related to gestation, but may be reduced by use of antenatal steroids, lower volume fluid regimen and judicious use of phototherapy. However, there continues to be controversy as to the appropriate indications for treatment, varying from prophylaxis on the basis of gestation to treatment only when a PDA is demonstrably significant. The situation is further complicated by differing diagnostic criteria for ductal patency or significance. Prophylactic treatment is likely to result in up to 64% of babies being treated unnecessarily. Early treatment of significant or symptomatic PDA depends upon accurate diagnosis. PDA closure can then be achieved using medical means, with surgery reserved for patients in whom this fails or in whom there are contra-indications. However, the optimum timing for intervention remains unknown.

Anti-Inflammatory Agents, Non-Steroidal↗