Percutaneous closure of the small patent ductus arteriosus using occluding spring coils

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.

Amplatzer Device closure of Atrial Septal Defects and Patent Ductus Arteriosus: Initial Experience

Surgical closure of Atrial Septal Defects (ASD) and Patent Ductus Arteriosus (PDA) can be performed successfully with low mortality. However, the morbidity associated with general anaesthesia, thoracotomy, cardiopulmonary bypass, postoperative monitoring in the intensive care unit, several days of hospital stay and the requirement of blood products is considerable. The expense associated with this morbidity, operative scar and the psychologic trauma to the patient and parents are additional disadvantages of surgery. Hence, the closure of these defects by transcatheter methods with various devices has been evaluated worldwide. We report the initial experience at our centre with closure of secundum ASDs and large PDAs with the Amplatzer Septal Occluder and Amplatzer Duct Occluder.

Influence of ductal size on the results of transcatheter closure of patent ductus arteriosus with coils

To assess the influence of ductal size on the results of transcatheter closure of patent ductus arteriosus (PDA) with coils, 154 consecutive patients were studied prospectively. Ductal size was defined as the narrowest diameter of ductus measured on aortography. All patients were divided into 5 groups according to ductal size: < 1 mm, 1-1.9 mm, 2-2.9 mm, 3-3.9 mm, and > or = 4 mm. The occlusion of PDA with coils was performed through a transarterial approach. The results were evaluated by angiography at 10 minutes and by color Doppler echocardiography at 1 day, 2 days, 1 week, 1 month, 3 months, 6 months, and 12 months after the procedure. The immediate occlusion rates for ductal sizes < 1 mm, 1-1.9 mm, 2-2.9 mm, 3-3.9 mm, and > or = 4 mm were 89.7%. 75.4%, 51.4%, 30.8%, and 40%, respectively; whereas the occlusion rates at 12-months follow-up were 100%, 98.5%, 97.3%, 69.2%, and 80%, respectively. There were no significant differences in occlusion rate at 12-months follow-up among the groups with ductal sizes < 3 mm or among the groups with ductal sizes > or = 3 mm. The occlusion rate for ductal size < 3 mm at each follow-up time was significantly higher than that for ductal size > or = 3 mm (10 minutes: 71.8% vs 34.8%. P = 0.001; 12-months: 98.5% vs 73.9%, P < 0.001). The occlusion rate of residual shuntings at 12-months follow-up for ductal size < 3 mm was also significantly higher than that for ductal size > or = 3 mm (94.6% vs 60%, P = 0.007). The results of the present study demonstrate that ductal size < 3 mm had a higher occlusion rate than that for a size > or = 3 mm. PDA with a size > or = 3 mm may need other treatment strategies or other devices to achieve better results.

Angiographic and hemodynamic predictors for successful outcome of transcatheter occlusion of patent ductus arteriosus in infants less than 8 kilograms

Transcatheter occlusion of patent ductus arteriosus (PDA) using Gianturco coils (GCs) has been performed for the past decade. However, little has been written regarding anatomical and hemodynamic predictors for successful occlusion of the PDA in infants. This report is to evaluate the outcome of transcatheter occlusion of PDA in symptomatic infants less than 8 kg and to assess predictors of successful occlusion. Retrospective review of catheterization charts and cineangiograms of 42 symptomatic infants who underwent cardiac catheterization for attempted transcatheter occlusion of their PDA was conducted. The hemodynamic and angiographic data evaluated included the length/diameter (L/D) ratio, defined as the length divided by the narrowest diameter of the ductus arteriosus, and preocclusion pulmonary artery pressures. Thirty-one out of 42 patients (74%) had successful occlusion. Twenty-nine out of 42 infants had an L/D ratio > 3. Of these, 26 (90%) had successful occlusion of their PDA. Thirteen out of 42 patients had an L/D ratio < or = 3. Of these, 8 (62%) had unsuccessful occlusion. Complications encountered were transient loss of femoral arterial pulse (n = 6), coil embolization (n = 5), hemolysis (n = 2), and mild left pulmonary artery obstruction (n = 2). No permanent loss of femoral arterial pulse was noted. These complications resulted in no mortality and minimal morbidity. The L/D ratio was the strongest predictor of successful outcome, with an L/D ratio greater than 3.0 being more amenable to transcatheter occlusion (odds ratio of 4.6). Other predictors for success included lower preocclusion systolic, diastolic, and mean pulmonary artery pressure and smaller ductal diameter. Our conclusion was that infants less than 8 kg with an L/D ratio > 3.0 can safely and successfully undergo transcatheter occlusion of their PDA using transcatheter coils.

Comprehensive assessment of patent ductus arteriosus by echocardiography before transcatheter closure

BACKGROUND

Anatomic type and angiographic measurements of patent ductus arteriosus (PDA) are used to determine the suitability of transcatheter closure (TCC). The purpose of this study is to evaluate whether these PDA features can be obtained by 2-dimensional echocardiography (2DE).

METHODS

We retrospectively compared PDA measurements and type from 36 patients submitted to TCC between November 1995 and October 2000.

RESULTS

The patient age ranged between 2 months to 10.5 years (median = 1.2 years). A significant correlation was found between measurements of PDA minimal diameter (R(2) = 0.88) and diameter at aortic ostium (R(2) = 0.72); whereas a poor correlation existed between measurements of the ampulla length. The 2DE and angiographic PDA classification were concordant in 31 of 36 (86%) patients.

CONCLUSION

Our data support the use of 2DE measurements of PDA minimal diameter and PDA diameter at the aortic end to assess suitability for TCC. In the majority of cases, PDA type can be diagnosed by 2DE.

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.

Transcatheter closure of patent ductus arteriosus using Gianturco coils in adolescents and adults

We present the short- and intermediate-term results of transcatheter closure of patent ductus arteriosus with Gianturco coils in adolescents and adults. During a 5-year period, 55 patients (44 females, 11 males) with ages ranging from 14 to 72 years (median, 23) underwent attempted transcatheter closure of patent ductus with the Gianturco coils. The diameter of the narrowest segment of the ductus ranged from 0.8 to 7.6 mm (3.9 +/- 1.3 mm). The 55 patients were divided into three groups. Group I consisted of nine patients with a ductal diameter < or = 3 mm, group II consisted of 27 patients with a ductal diameter > 3 mm but < or = 4 mm, and group III consisted of 19 patients with a ductal diameter > 4 mm. Four- to five-loop Gianturco coils were used, which were deployed via retrograde aortic route. Multiple-coil technique was generally applied in group II patients. Balloon occlusion technique in combination with multiple-coil technique was generally used in group III patients. Deployment of coil was successful in 51 patients (93%) but failed in 4. The success rate of coil deployment in group I, II, and III were 100% (9/9), 96% (26/27), and 84% (16/19), respectively. A mean of 1.9 +/- 0.7 coils was deployed per patient. Of the four patients with unsuccessful coil deployment, three underwent surgery and one received implantation with Amplatzer duct occluder. Distal embolization of 21 coils occurred in 10 patients (3 in group II and 7 in group III), from whom 20 coils were retrieved with a gooseneck snare and 1 coil was removed during surgery. The mean diameter of ductus in the 10 patients with distal embolization was significantly larger than that in those without (5.2 +/- 1.4 vs. 3.7 +/- 1.1 mm; P < 0.01). Among the 51 patients with successful coil deployment, immediate complete closure was achieved in 20 (39%), while trivial to mild leak was present in 31 (61%). No significant complications were encountered. After a follow-up period ranging from 5 to 42 months, four patients had a small residual shunt and three underwent a second intervention with complete occlusion. None had left pulmonary artery stenosis documented with Doppler echocardiography. Transcatheter closure of ductus with the Gianturco coils is safe and feasible in the majority of adolescents and adults. Taking high embolization rate in patients with a ductus diameter > 4 mm into consideration, controlled-release coils, Buttoned device, or Amplatzer duct occluder can be a better choice.

Iatrogenic coarctation after coil occlusion of arterial duct

Coil occlusion of a patent ductus arteriosus was performed in an 8.5-month-old girl with a large left-to-right shunt through a wide arterial duct. Post-occlusion echocardiography revealed iatrogenic obstruction of the aorta caused by protrusion of the loops of the Jackson coil into the descending aorta. The problem resolved spontaneously during follow-up.

Transcatheter patent ductus arteriosus occlusion: evolution of techniques and results from the 1990s

OBJECTIVE

To review the evolution of transcatheter patent ductus arteriosus (PDA) occlusion techniques and results.

METHODS

A single institution, retrospective review including all patients with intention to close a PDA from 1991 to 1998, with no exclusions.

RESULTS

Rashkind occluder (n = 65), sideris double-button (n = 6), Cook detachable coil (n = 28) and Amplatzer ductal occluder (n = 4) were used. Successful implantation occurred in 99 of 103 patients. There was a need for a second transcatheter procedure to close residual ductal shunting in 12% of patients: Rashkind umbrellas (n = 8), double-button (n = 1), coils (n = 3). Eight patients (8%) required surgery, including 4 of 6 patients with the double-button occluder.

CONCLUSIONS

The Rashkind occluder and the Sideris double-button device both had an unacceptably high rate of residual shunts requiring a second transcatheter procedure or surgical closure. Detachable coils and the Amplatzer ductal occluder have become the current technology of choice for transcatheter PDA closure with high success rates.

Catheter closure of moderate to large sized patent ductus arteriosus using the simultaneous double or triple coil technique

BACKGROUND

Although the clinical experience with transcatheter closure of the patent ductus arteriosus using the coils has grown rapidly, one important complication of this procedure using the conventional Gianturco coil was the migration of coils into peripheral vessels. This is especially for patients with a relatively larger size ductus and the risk for such complications could be increased. In this situation, the detachable coil may have some technical benefits to perform coil occlusion and reduce the incidence of complications.

METHODS

We describe the clinical efficacy of a simultaneous double or triple coil occlusion technique using the Cook detachable coil or bioptome delivered 0.052 inch Gianturco coil to close the ductus arteriosus. This was performed in patients whose ductus diameter was greater than 3.0 mm.

RESULTS

From February 1995 to December 2000, 118 patients with patent ductus arteriosus were treated by coil occlusion using Cook detachable coils, of whom 58 patients whose minimum diameter of ductus > or = 3.0 mm were reviewed. All patients had successful placement of coils. According to the evaluation by color flow mapping, a trivial shunt was observed in 17 patients (29%) within 24 h after the procedure. In 11 out of 17 patients, a residual shunt was not detected 1 month after the procedure. At 6 months after the procedure, the residual shunt was detected only in three patients.

CONCLUSIONS

Although this study did not calculate the statistical significance between detachable and non-detachable coils in term of occlusion rate, our institutional experience suggests that the simultaneous double or triple coil technique using the detachable or 0.052 inch Gianturco coils can reduce the prevalence of coil migration or complications.

Patent ductus arteriosus equipment and technique. Amplatzer duct occluder: intermediate-term follow-up and technical considerations

Between May 1997 and June 2000, 69 patients, ages 0.1 to 34 years, underwent attempted anterograde transcatheter closure of a patent ductus arteriosus (PDA) using the Amplatzer Duct Occluder (ADO). The ADO is a cone-shaped, self-centering, and repositionable occluder made of nitinol wire mesh. A 5Fr to 7Fr sheath was used for the delivery of the device. The mean PDA diameter (at the pulmonary end) was 4.6 +/- 1.9 mm (range 1 mm-8.5 mm). Sixty-seven of the 69 patients had successful device placement. The mean ADO smallest diameter was 6.9 +/- 1.8 mm (range 4 mm-12 mm). Complete angiographic closure occurred in 62 (92.5%) of 67 patients (95% confidence interval, 88.22%-98.77%). In five patients, there was a trivial residual shunt immediately after the procedure. At 24 hours, color Doppler flow imaging revealed complete closure in all 67 (100%) patients. The unsuccessful attempts occurred in two patients with a small, 1-mm diameter native PDA and residual PDA after surgical occlusion. Fluoroscopy time was 7.6 +/- 1.8 minutes (4 min-18 min). No complications were observed. At a median follow-up of 1.5 years (range 0.25 to 3.2 years), all patients had complete closure without complications. We conclude that transcatheter closure using the ADO is a highly effective and safe treatment for most patients with PDA.

Gianturco-Grifka vascular occlusion device for closure of patent ductus arteriosus

We retrospectively reviewed the results of catheter closure of patent ductus areteriosus using the Ginaturco-Grifka vascular occlusion device in our institution. All patients in whom it was attempted had successful implantation, complete closure on follow-up, and no complications.

Early experience with the Amplatzer ductal occluder for closure of the persistently patent ductus arteriosus

Using an Amplatzer duct occluder, 106 patients (weight 21 +/- 18 kg) underwent an attempt at catheter closure of a persistently patent ductus arteriosus (PDA). Their age ranged from 22 days to 48 years. The PDA measured between 1.2 to 8.1 mm at its narrowest diameter. The device was successfully implanted in 105 patients. The immediate closure rate was 70% and gradually increased to 100% at 1-month follow-up. There was no clinical evidence of hemolysis and no incidence of device embolization or bacterial arteritis. Doppler evaluation showed no evidence of aortic arch or pulmonary artery obstruction. The device, which is currently undergoing multicenter clinical trial in the United States, is proving to be a safe and effective device for closure of the persistently PDA.

Simultaneous double or triple coil technique for closure of moderate sized (> or = 3.0 mm) patent ductus arteriosus

One important complication of coil occlusion of patent ductus arteriosus using the conventional Gianturco coil is migration of coils into peripheral vessels. Especially in patients having relatively larger size ductus, the risk for such complication could be increased. In this regard, a detachable coil may have some technical benefits in performing coil occlusion and reducing the incidence of complications such as migration of coil. Based on our clinical experiences, we describe the clinical efficacy of a simultaneous double or triple coil occlusion technique using the Cook detachable coil system to close the ductus arteriosus, especially in patients whose ductus diameter more than 3.0 mm.

Comparison of two transcatheter closure methods of persistently patent arterial duct

A randomized trial of arterial duct occlusion with a double umbrella (DU) or wire coil (WC) was undertaken for patients <18 years of age, weighing >10 kg with isolated ducts < or = 3 mm in diameter. Baseline, procedural, and outcome characteristics were compared in an intention-to-treat analysis according to randomization group. From 40 consecutively screened patients, 2 were not enrolled due to a ductal diameter of >3 mm on initial aortography, 38 patients were randomized to either the DU (n = 20) or WC (n = 18) groups. The groups did not differ significantly with respect to age, weight, gender, duct size, type, or branch pulmonary artery diameters. Crossover occurred only in the DU group, where 4 patients (20%) had a ductal diameter of < or = 1 mm and could not be entered for umbrella placement. All remaining DU group patients had ductal diameters of > or = 1.3 mm (p <0.0001). There were no embolizations or secondary implants in the DU group, but in the WC group there was 1 early and 1 late embolization, with 6 patients (33%) with > or = 2 coils. Mean times for the procedure (DU 68+/-19 minutes; WC 65+/-27 minutes; p = 0.70) and fluoroscopy (DU 14+/-4 minutes; WC 11+/-6 minutes; p = 0.22) did not differ significantly. Angiographic duct closure was documented in 4 of 13 patients (31%) of the DU group and 4 of 18 patients (22%) of the WC group (p = 0.69). Combined with an echocardiogram, closure in 11 of 17 patients with DU (65%) and 13 of 18 patients with WC (72%) (p = 0.64) was documented before hospital discharge. One WC group patient received thrombolytic therapy for a femoral artery thrombus. Follow-up at a median of 6.5 months (range 3.2 to 37) showed closure by Doppler echocardiography in 15 of 19 patients with DU (79%) versus 14 of 18 patients with WC (78%) (p = 1.0). Thus, with a tendency toward similar procedural characteristics and outcomes, the higher cost of the DU system compared with coil implants favors the use of coils for closure of the small arterial duct.

Transcatheter closure of persistent arterial ducts with different types of coils

BACKGROUND

Different types of coils have been designed for transcatheter closure of persistent arterial ducts. We compared the efficacy and safety of three types of coils: Gianturco coils (Cook), Cook detachable coils (Cook), and Duct Occlud devices (pfm).

METHODS

Sixty-three patients underwent coil occlusion of arterial ducts between April 1995 and July 2000. The mean age and weight were 4.8+/-3.4 years and 16.5+/-7.6 kg, respectively. The results and complications of ductal occlusion among the three types of coils were compared. Kaplan-Meier analysis was used to assess reduction in the prevalence of residual shunt with time, and multiple regression analysis was performed to identify predictors of complete occlusion.

RESULTS

Coil occlusion of persistent arterial ducts that measured 2. 2 +/- 0.8 mm was feasible in 90% (57/63) of patients. Gianturco coils were used in 29, Duct Occlud devices in 16, and Cook detachable coils in 12 patients. The prevalence of residual shunt at 24 hours, 6 months, 12 months, and 24 months was 42%, 20%, 18%, and 14%, respectively. The reduction in prevalence of residual shunt with time tended to be greater when Gianturco coils were used (P =. 067). Logistic regression identified the use of Gianturco coils to be a significant predictor of complete ductal occlusion on follow-up (P =.04). Pull-through of coils occurred in 4.8% (3/63) and coil embolization in 6.3% (4/63). There was no association between the type of coil and the risk of embolization (P = 1.00).

CONCLUSIONS

Transcatheter occlusion of small persistent arterial ducts with coils is safe and effective. There is no advantage of detachable coils (Cook detachable coils and Duct Occlud devices) over nondetachable Gianturco coils in reducing the risk of embolization. Our findings are in favor of the inexpensive, but more effective, Gianturco coils for occluding small arterial ducts of 3 mm or less.

Recommendations of the British Paediatric Cardiac Association for therapeutic cardiac catheterisation in congenital cardiac disease

The aims of these recommendations are to improve the outcome for patients after, and to provide acceptable standards of practice of therapeutic cardiac catheterisation performed to treat congenital cardiac disease. The scope of the recommendations includes all interventional procedures, recognising that for some congenital malformations, surgical treatment is equally as effective as, or occasionally preferable to, interventional treatment. The limitations of the recommendations are that, at present, no data are available which compare the results of interventional treatment with surgery, and certainly none which evaluate the numbers and types of procedures that need to be performed for the maintenance of skills. Thus, there is a recognised need to collect comprehensive data with which these recommendations could be reviewed in the future, and re-written as evidence-based guidelines. Such a review will have to take into account the methods of collection of data, their effectiveness, and the latest developments in technology. The present recommendations should, therefore, be considered as consensus statements, and as describing accepted practice, which could be used as a basis for ensuring and improving the quality of future care.

Comparison of the one-and-a-half-year results of closure of patent ductus arteriosus by transcatheter coils placement with surgical ligation

Patent ductus arteriosus (PDA) is a common type of congenital cardiovascular lesion. It usually needs surgical ligation in a full-term baby after 1 year of age. Transcatheter implantation of coils was introduced for the closure of small- to moderate-sized PDA in 1992. From November 1995 to November 1998, the authors closed the PDA in 153 patients by transcatheter implantation of coils and by surgical ligation in 10 patients. One hundred fourteen of them were studied for more than 1(1/2) years. The regular follow-up studies, including physical examination; electrocardiography; and pulsed, continuous-wave, and color Doppler flow mapping, were performed on day one and day 2, and 1 week, 1 month, 3 months, 6 months, and 1 year after the procedure. The results of the closure of PDA by surgical ligation or coil placement were compared and analyzed in all the patients.

Closure of the patent ductus arteriosus with the amplatzer PDA device: immediate results of the international clinical trial

The purpose of this article is to present the immediate and short-term results of the international registry of transcatheter closure of patent ductus arteriosus (PDA) using the Amplatzer duct occluder (ADO). Three hundred sixteen patients (221 females) in various centers with clinical and/or echocardiographic evidence of PDA underwent an attempt of catheter closure at a median age of 2.1 years and median weight of 10.7 kg. The median Qp/Qs ratio was 2.3, the median length of the PDA was 6.7 mm and the median diameter of the PDA at its narrowest point (usually the pulmonic end) was 3.8 mm. Immediately after closure and by angiography, the PDA was completely closed in 177/311 patients (56%) and within 24 hr the complete closure rate increased to 76% (235/308). Complications were encountered in 15 patients, including 1 major complication due to device embolization and subsequent death, 6 moderate complications, and 8 minor complications. The median fluoroscopy time was 12 min and the median total procedure time was 70 min. One hundred fourteen patients reached the 6-month follow-up. Color Doppler echocardiography demonstrated complete closure in 109 patients (94.6%). Thirty-eight patients reached the 1-year follow-up mark. There was complete closure in 100% of the patients as documented by color Doppler echocardiography. So far there has been no episodes of delayed device migration, endocarditis, thromboembolism, and wire fracture or device disruption. We conclude that the ADO is safe and effective in most patients with PDA up to a diameter of 10.6 mm. Further clinical trials are underway to assess its long-term safety and efficacy.

Transcatheter occlusion of patent ductus arteriosus using a 0.052-inch coil--immediate results

Coil occlusion of a patent ductus arteriosus (PDA) was attempted with a 0.052-inch Gianturco coil. The patients' ages and body weights at occlusion ranged from 5.8 to 19.7 (12.3+/-5.0, mean+/-SD) years and 18.9-99.1 (44.8+/-23.7) kg, respectively. Three types of 0.052-inch Gianturco coils with loop diameters (mm) and coil lengths (cm) of 6x8 (diameter x length), 8x8, or 8x10 were used. The delivery system was prepared as reported by Hays et al with slight modification. The minimal diameter and the Qp/Qs of the PDA ranged from 2.3 to 4.7 (3.4+/-0.7) mm, and 1.1-1.8 (1.5+/-0.3), respectively. There were 7 cases with type A PDA and 3 with type B, and coils were successfully deployed in all. Complete occlusion in the catheter laboratory was achieved in 4 cases. A minor leak disappeared within 24 h in 3 cases and at 3 months follow-up in 1 case. A tiny leak without a heart murmur persisted in 2 cases at 3 months' follow-up. No procedure-related complications occurred. This technique has significant advantages over previously reported techniques using a 0.038-inch coil for type B, or A PDA with a minimal diameter of 3-4 mm or more.

Interventional pediatric cardiology: device closures

Surgical treatment of various septal defects has been long established. With the advances in transcatheter therapy dilatation techniques for valvular stenosis and vascular obstruction have become established procedures. Closure of septal defects in the catheterization laboratory has also been introduced; some of these have come into regular use in current practice. In 1967, Porstmann et al reported the use of Ivalon plug to close patent ductus arteriosus (PDA). Since then, several devices have been used including Rashkind PDA ocluder (not being used now), Gianturco coils, detachable coils (for small PDA), CardioSEAL and other umbrella devices and Amplatzer PDA occluder. Closure rates vary from 95-98% in most series, however, some of these devices are very expensive, more so, when compared to the cost of surgical ligation of PDA. Catheter closure of secundum atrial septal defect (ASD) has also been done by various devices like clamshell device, Sideris Buttoned device, ASDOS device, Amplatzer device and cardioSEAL. So far no device has been accepted as ideal for every case, however, Amplatzer device has been used most extensively. Issues such as completeness of endothelialisation, incidence of late arrhythmias, endocarditis remain uncertain. However, in select population of ASD cases with a central secundum defect, device closure is being used increasingly. Device closure of ventricular septal defect remains challenging and controversial and is probably available to a small group of children with defects that are difficult to close surgically and involve higher risk.

Five-loop coil occlusion of patent ductus arteriosus prevents recurrence of shunt at follow-up

Recent reports suggest reopening of the patent ductus arteriosus (PDA) after complete occlusion with three-loop Gianturco coils. We hypothesize that five-loop coils may produce a larger thrombus than three-loop coils, which will result in no or less probability of recanalization of PDA during follow-up. This study is designed to test this hypothesis. Follow-up echocardiographic and Doppler data of 30 patients who underwent five-loop coil occlusion of small to medium-sized PDA during a 33-month period ending December 1998 were examined. Thirty patients had no residual shunt on echo Doppler study on the day following the procedure and were followed for 6 to 30 months (median, 12) after coil implantation. At the last follow-up study, none of the patients had a residual shunt and left atrial size decreased. Careful pulsed, continuous wave, and color Doppler interrogation of left/main pulmonary artery junction and proximal descending aorta did not reveal any evidence for obstruction. The follow-up data suggest that complete occlusion of small- to medium-sized PDAs is feasible with five-loop coils without evidence for recanalization at a mean follow-up of 12 months. Much longer (2 to 5 years) follow-up data may be necessary to confirm these observations. We speculate that a greater degree of thrombosis is produced within the ductus by the five-loop coils, which in turn may be responsible for lack of shunt recurrence. We recommend use of five-loop instead of three-loop coils for transcatheter occlusion of small- to medium-sized PDAs.

Immediate and early results of closure of moderate to large patent arterial ducts using the new Amplatzer device

OBJECTIVES

Our aim was to assess the immediate and short term results of closure of moderate and large patent arterial ducts using the self-expanding and repositionable Amplatzer device.

METHOD

We attempted closure in 25 patients (10 Females and 15 males) using the Amplatzer occluder. Their median age was 48 months with a range from 8 months to 26 years and median weight of 14 kg with a range from 4.5 kg to 48 kg. The mean ductal diameter was 4.1 mm (S.D 1.51 mm). A 6F/7F long sheath was used to deliver the device. Follow up was performed with colour- flow mapping of the pulmonary trunk within 24 hours, at 3 months, and 6 months of closure.

RESULTS

Of the 25 patients, the device was placed successfully in 23. Concurrent angiography showed immediate closure in 12 patients, while 8 had trivial shunting and 3 had mild shunting. Within 24 hours, Doppler examination revealed complete closure in all but three patients, who had a mild residual shunt. Two attempts were unsuccessful. Both these patients underwent successful surgical ligation. All except one patient were discharged on the next day. Of the 23 patients, 15 (65%) have been followed up for 3 months, while 8 (35%) have completed 6 months of follow-up. Of the three patients initially with mild residual flow, two had completely closed at 3 months The one remaining patient is yet to be seen at the 3 month follow-up. Thus, at 3 months, all patients studies had shown complete closure.

CONCLUSION

Antegrade transcatheter closure using the Amplatzer duct occluder is an efficacious treatment for bigger patent arterial ducts. Long-term follow-up is necessary to show sustained benefits and confirm the absence of side effects.

Endothelialization of the coils used to occlude a persistent ductus arteriosus: an angiographic study

To assess the endothelialization of the coils used to close a persistent ductus arteriosus (PDA), the present study comprised a review of the follow-up aortograms and pulmonary angiograms in 25 patients who underwent coil occlusion. The minimal diameter and the length of the PDA were measured prior to the procedure, and the shortest distance between the aortic end of the deployed coil and the aortic end of the PDA was measured after coil deployment. Evidence of endothelial coverage of the coil was sought on follow-up angiograms performed 6-24 (15+/-5) months later and the factors that determined the thickness of the endothelial coverage on the aortic end were investigated. Separation of the coil and the contrast column were detected at the aortic end in all cases and at the pulmonary end in 18 of 25 cases. The thickness of the separation ranged from 0.4 to 1.3 (0.7+/-0.2) mm at the aortic end and 0.3 to 0.8 (0.6+/-0.2) mm at the pulmonary end. The length of the ductus and of the ampulla had a significant positive correlation with the thickness of the aortic end separation. Apparent endothelial coverage of the coil was completed by 6 months after coil occlusion. Infective endocarditis or thromboembolism is an unlikely complication once endothelium covers the implanted coil.

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.

Transcatheter coil occlusion of the small patent ductus arteriosus (<4 mm): improved results with a "multiple coil-no residual shunt" strategy

We report our experience with transcatheter occlusion of the small PDA using Gianturco coils comparing a single coil strategy to a "multiple coil-no residual shunt strategy". Fifteen patients (Group I) had a single coil only placed irrespective of residual shunting and 20 (Group II) were treated using the no residual shunt strategy. Age, minimal PDA diameter, PDA length and PDA types were similar between groups. Closure rates in Group I patients were 60%, 80% and 87% at <1 month, 6 months and 1 year, respectively. In Group II, the <1 month and 6 month closure rates were 100%. The costs and hospital charges for coil closure were comparable to a concurrent surgical group; the total charges (hospital plus physician) were less for Group I, but similar between Group II and the surgical group. The complication rate for coil closure was significantly less than surgical closure. From these data, transcatheter closure with multiple coils can achieve the same closure rate as surgery at similar hospital charges with fewer complications.

Patent Ductus Arteriosus

In the absence of irreversible pulmonary hypertension, closure of clinically detectable patent ductus arteriosus (PDA) is usually recommended in adults. Device closure obviates the need for general anesthesia and a surgical incision and eliminates postoperative pain, long convalescence, and lifelong scarring. Over the past 20 years, the efficacy and safety of transcatheter device closure of PDA in adults has been established. Even though the immediate success rate is lower with transcatheter device closure than with surgical closure, transcatheter reintervention for residual clinical shunts is very effective at abolishing residual leaks. The late complete closure rate, as determined by echocardiography, is very similar with surgical closure and with device closure. The clinical significance of silent residual shunts is unknown. In patients with silent residual shunts, the use of prophylactic antibiotics is as of yet recommended. Occlusion devices should be used whenever possible in adults, and surgical closure of patent ducts should be reserved for patients with larger ducts. The method of ductal closure should be selected on the basis of the quality of and experience with available interventional and surgical resources. Emerging minimally invasive surgical treatments seem promising, but further experience and follow-up are needed before widespread application of these techniques can be recommended.

Long-term outcome of transcatheter coil closure of small to large patent ductus arteriosus

Coil closure of patent ductus arteriosus (PDA) has become an accepted alternative to surgical closure in most pediatric cardiac centers. However, little is known about the mid-to long-term outcome of this procedure. Therefore, we evaluated the immediate, short-, and long-term outcome of transcatheter coil closure (TCC) of PDA using single or multiple Gianturco coils or the Gianturco-Grifka Vascular Occlusive Device (GGVOD). One hundred forty-nine patients underwent an attempt at TCC of their PDAs at a median age of 2.4 years (2 weeks to 55 years) and median weight of 13.5 kg (2.3-87 kg). There were 33 patients < 1 year of age. The median PDA minimal diameter was 2 mm (0.4-7 mm) with 26 patients whose PDA minimal diameter was > 4 mm. A 4 Fr catheter was used for coil deployment in 136 patients, a 3 Fr in 4, and an 8 Fr in 4 patients who received the GGVOD. A single coil was used in 77 patients and multiple coils (2-6) were used in 66 patients. One hundred forty-six patients had successful closure (142 had immediate complete closure and 4 had residual shunt), 3 patients failed the initial attempt (2 underwent surgical ligation and 1 had a successful second attempt a year later). Of the four patients with residual shunt, three underwent a second procedure with implantation of 1-3 coils resulting in complete closure in all and one patient had spontaneous resolution of the residual shunt. Complications were encountered in nine patients: six had coil migration with successful retrieval in four; two had left pulmonary artery stenosis (2.4 kg and 6.3 kg infants), and one patient had loss of femoral arterial pulse. The median fluoroscopy time was 16 min (2-152 min). One hundred forty-two patients had the procedure as an outpatient, five patients stayed greater than 24 hr, and two of these patients were in hospital for 1 month for noncardiac reasons. At a median follow-up interval of 3.0 years (1 month to 5.1 years), there were no episodes of delayed coil migration, delayed recanalization, thromboembolic episodes, or bacterial endocarditis. Lung perfusion scans performed at a median follow-up interval of 1.6 years in 31 patients who received multiple coils revealed 45% +/- 5% blood flow to the left lung. Long-term follow-up of coil closure of PDA indicates that the technique is safe and effective for most patients with PDA up to a diameter of 7 mm.

Radiation exposure to children during coil occlusion of the patent ductus arteriosus

The risks of excessive exposure to ionizing radiation are well described and measures are routinely taken to limit such exposure to both patient and personnel in the catheterization laboratory. Coll occlusion of the patent ductus arteriosus (PDA) as well as other more complex pediatric interventions has raised concern regarding radiation exposure, particularly as minimally invasive surgical techniques are being developed which lack such exposure risk. In eight consecutive patients, aged 0.7-7 years (median, 2.3 years), coil occlusion of a PDA was performed and surface entrance radiation dose determined by thermoluminescent dosimetry (TD). Total cumulative doses (PA + lateral dose) were also calculated for each patient. Entrance and cumulative dose was likewise measured in 12 patients undergoing standard diagnostic catheterization (DC) and in 5 consecutive patients undergoing pulmonary balloon valvuloplasty (PBV). The groups were comparable in age, weight, and body surface area (BSA). Total cumulative dose in the PDA patients was 97 +/- 25 mGy (mean +/- SE). There was no significant difference between the three groups in entrance dose absorbed at each location or in total cumulative dose. The mean total fluoroscopy time in the PDA occlusion group was significantly less than that of the PBV group (10.1 +/- 1.81 min vs. 19.3 +/- 2.29 min, P < 0.05) but was comparable to the DC group (13.2 +/- 1.5 min, P = NS). When the subjects were analyzed collectively, no correlation between fluoroscopy time and measured entrance dose was observed. The strongest correlates of total cumulative dose were patient weight (r = 0.67, P < 0.001) and BSA (r = 0.62, P = 0.001). Patients undergoing coil occlusion of a PDA are not exposed to increased radiation entrance dose compared to those undergoing standard DC and PBV. Furthermore, surface entrance radiation dose as determined by TD varies according to patient size for a given fluoroscopy time.

Stretching of the ductus: an important factor in determining the outcome of coil occlusion

The present study measured the minimal diameter of the ductus (minimal D), the stretched minimal diameter (stretched D), and the stretch index (SI) before coil occlusion in 25 patients with a patent arterial duct. The following factors were compared in the success group (22 cases, coil successfully placed after initial deployment) versus the failure group (3 cases): minimal D, stretched D, SI, the sum of the loop diameter of coils (the loop diameter), the sum of the product of the loop diameter and the number of loops (the loop diameter and number), the loop diameter/minimal D, the loop diameter/stretched D, the loop diameter and number/minimal D, and the loop diameter and number/stretched D. In the failure group, minimal D, stretched D, SI, the loop diameter, and the loop diameter and number were larger than in the success group. The loop diameter/stretched D, and the loop diameter and number/stretched D were smaller in the failure group. Although the loop diameter and number/minimal D was slightly smaller in the failure group, the loop diameter/minimal D was comparable. It is concluded that the stretched D is more reliable than minimal D to determine the appropriate size of coil for successful initial deployment.

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.

Transarterial occlusion of patent ductus arteriosus with Gianturco coils in pediatric patients: a preliminary result in central Taiwan

OBJECTIVE

We wish to present the preliminary result of transarterial occlusion of patent ductus arteriosus (PDA) with Gianturco coils in pediatric patients in central Taiwan.

MATERIALS AND METHODS

We attempted occlusion of PDA with Gianturco coils in a total of 26 consecutive patients, 13 infants and 13 children, 23 female and three male, between July 1 1997 to September 30 1998. Median patient age was 2.57 years (from 0.25 to 14.02 years old). Median patient weight was 10.8 kg (4.0 to 36.0 kg). Premature babies with PDA, full-term babies who were less than three months old and patients who had other congenital heart disease were not included in this study. All PDAs were approached transarterially from the femoral artery. Coils were selected to provide a helical diameter that was twice or more the minimum ductus diameter and a length approximating five loops. In five patients who had a PDA diameter > or =3.5 mm, we used a snare technique to assist coil delivery beforehand, and to test coil stability, or to retrieve coil that had migrated to the pulmonary artery afterwards. Physical auscultation, chest radiographs and echocardiography with color Doppler were done in all patients within 24 h, and one, two, three, six and 12 months after coil occlusion.

RESULTS

The median ductus minimum diameter was 2.3 mm (range, 1.0 to 4.7 mm). Fifteen patients had the megaphone type (type A), four had the window type (type B), five had the tubular type (type C), one had the aneurysmal type (type D) and one had the elongated conical type (type E). Twenty-one patients underwent single coil occlusion and five had multiple coils occlusion. Twenty-one patients had immediate angiographic closure of the ductus and disappearance of heart murmur at 15 min after the procedure. Dark-brown urine (hemoglobinuria) was found in one patient, 10 h after the first procedure, due to a mild residual ductal shunt. Two more coils were implanted in a second procedure that was performed within 24 h, and the ductus was completely occluded. The dark-brown urine regressed. At one month follow-up, four patients had mild residual ductal shunts, which were completely occluded by one more coil in three patients and by two more coils in the other patient. Malpositioned coils were deployed in five patients immediately after the procedure. In total, the closure rate at 15 min, within 24 h, and at one, two, three, six and 12 months were 81, 85, 85, 100, 100, 100 and 100%, respectively. In one year of follow-up, there was no instance of coil migration, ductus reopening or stenosis of the left pulmonary artery.

CONCLUSIONS

Transarterial occlusion of PDA, with a Gianturco coil having approximately five loops, can be effectively achieved in patients with a minimum ductus diameter up to 4.7 mm. In patients with a ductus of more than 3.5 mm, the snare-assisted technique was employed advantageously to control coil delivery with accuracy and stability. Coil malposition or migration can be easily retrieved using a 10-mm Nitnol snare catheter. Hemoglobinuria, due to intravascular hemolysis, may regress within 24 h after the second attempt at coil implantation.

Does ductal occlusion with the gianturco coil cause left pulmonary artery and/or descending aorta obstruction?

Thirty-two patients (median age 4.5 years) underwent transcatheter Gianturco coil occlusion of a patent ductus arteriosus. Transthoracic echocardiography was performed the day after coil placement and at intermediate follow-up (median 8.6 months). Echocardiographic results were compared with angiographic and hemodynamic data obtained during catheterization. Two-dimensional (2D) echocardiography performed the day after ductal occlusion displayed evidence of coil protrusion into the left pulmonary artery in 28 of 31 patients (90%) and into the descending aorta in 17 of 29 (59%). However, pulsed Doppler analysis demonstrated normal left pulmonary arterial flow velocities in 28 of 29 patients (97%) and normal descending aortic flow velocities in 26 of 27 (96%). Pulse Doppler results were corroborated by angiographic and hemodynamic catheterization data, which showed no evidence of adjacent vessel obstruction. Peak Doppler velocities among patients with and without 2D echocardiographic left pulmonary artery or descending aorta coil impingement did not differ significantly. The discrepancy between 2D and pulse Doppler findings did not change significantly at intermediate follow-up. Thus, transcatheter occlusion of the patent ductus arteriosus with properly implanted Gianturco coils does not cause significant obstruction to flow in the left pulmonary artery or descending aorta despite frequently misleading 2D echocardiographic images of coil impingement on these vessels.

Interventional cardiac catheterization

Over the past decade, transcatheter interventions have become increasingly important in the treatment of patients with congenital heart lesions. These procedures may be broadly grouped as dilations (e.g., septostomy, valvuloplasty, angioplasty, and endovascular stenting) or as closures (e.g., vascular embolization and device closure of defects). Balloon valvuloplasty has become the treatment of choice for patients in all age groups with simple valvar pulmonic stenosis and, although not curative, seems at least comparable to surgery for congenital aortic stenosis in newborns to young adults. Balloon angioplasty is successfully applied to a wide range of aortic, pulmonary artery, and venous stenoses. Stents are useful in dilating lesions of which the intrinsic elasticity results in vessel recoil after balloon dilation alone. Catheter-delivered coils are used to embolize a wide range of arterial, venous, and prosthetic vascular connections. Although some devices remain investigational, they have been successfully used for closure of many arterial ducts and atrial and ventricular septal defects. In the therapy for patients with complex CHD, best results may be achieved by combining cardiac surgery with interventional catheterization. The cooperation among interventional cardiologists and cardiac surgeons was highlighted in a report of an algorithm to manage patients with tetralogy of Fallot or pulmonary atresia with diminutive pulmonary arteries, involving balloon dilation, coil embolization of collaterals, and intraoperative stent placement. In this setting, well-planned catheterization procedures have an important role in reducing the overall number of procedures that patients may require over a lifetime, with improved outcomes.

DuctOcclud--implant for transcatheter closure of patent ductus arteriosus

The DuctOcclud implant is a metal coil device designed for transcatheter closure of small to moderate size patent ductus arteriosus, a Congenital Heart Disease in which a vessel-like communication between the aorta and the pulmonary artery persists after birth. The paper describes the design of the device, its delivery system, and the implant procedure. It also reviews and reports the experimental and the clinical experiences accumulated utilizing the device for occlusion of patent ductus arteriosus.

[Ductus closure in adults with the Rashkind device: comparative results]

INTRODUCTION

Catheter occlusion of the persistent ductus arteriosus with Rashkind device is an alternative to the surgical closure demonstrated in children, however a few results have been reported of occlusion in adults.

METHOD

From 1990 to 1996 in 127 patients with persistent ductus arteriosus undergoing occlusion by Raskind device. Two groups according age: 105 children (< 14 years) and 22 adults (> 14 years), were studied retrospectively. The results were analysed by immediate aortogram and follow-up at 24 hours, 6 and 12 months by color-Doppler echocardiograms.

RESULTS

The adults were frequently asymptomatic (86%) and with high incidence (59%) of silent ductus. Similar QP/QS (1.61 +/- 0.47 in adults vs 1.49 +/- 0.51) was calculated although pulmonary pressure was superior in children (12.50 +/- 2.97 vs 16.84 +/- 5.88 mmHg; p = 0.003). In group > 14 years the ductal anatomy favorable (Krichenko type A or B) was more frequent (91% vs 73%; p = 0.06) and ductal diameter significantly higher (3.03 +/- 1.50 vs 2.41 +/- 0.96 mm; p = 0.009). In adults 17 mm umbrella were used more frequently (91 vs 61%; p = 0.02). Absence complications (embolization, bacteremia, haemolysis, proximal stenosis of the left pulmonary artery) were found in adults against 4.72% in children. The occlusion were more effective in adults specially in early controls: 55% vs 34% (p = 0.09), 82% vs 69%, 91% vs 77% and 95% vs 83% (p > 0.10). Multivariate analysis identified age as an independent predictor of complete occlusion.

CONCLUSION

Our experience in transcatheter occlusion of persistent ductus arteriosus with Rashkind device in adults support the efficacy, safety and excellent early results despite higher incidence of silent asymptomatic ductus.

Interventional procedures for congenital heart disease

Interventional techniques available for use in treating congenital heart disease include balloon dilation of valves and vessels, stent placement and coil embolization of collaterals, patent ducts and other arterial fistulae. In addition, a variety of devices for closure of atrial and ventricular septal defects and patent ducts currently are under investigation. Radiofrequency ablation of arrhythmias also is applicable to the pediatric population.

Follow-up after coil closure of patent ductus arteriosus

A prospective serial follow-up after coil closure of patent ductus arteriosus in 84 patients showed a cumulative duct closure up to 96% at the end of 2 years. Five patients underwent transient recanalization, and 4 patients required repeat procedure for residual shunt or recanalization.

Spring coil retraction in coil occlusion of persistent ductus arteriosus

AIMS

To present the short and intermediate term results of coil occlusion of persistent ductus arteriosus and the results of radiographic measurements of spring coils implanted to treat patent ducts.

PATIENTS

22 children underwent coil occlusion. Their ages ranged from 2 years 9 months to 12 years 10 months (mean (SD) age, 6.5 (3.6) years). The duct diameter ranged from 1.0 to 3.5 mm at the narrowest point (mean 2.6 (0.7) mm). In 11 of the children regular coils were implanted using the non-attached system, while in the other 11 the detachable coil embolisation system was used.

RESULTS

12 children (55%) had no significant residual leaks immediately after procedures involving a single coil delivery. The remaining 10 (45%) had residual leaks immediately after the procedure, although no patient with a large duct showed residual leakage 18 months after the procedure. Radiographic measurement of the coils showed that all implanted coils retracted to 65-85% of their original size immediately after occlusion. This retraction was more evident in patients showing spontaneous closure of the residual shunt or having a coil 8 mm in diameter.

CONCLUSIONS

Coil embolisation is an acceptable method for occluding persistent ductus arteriosus. Retraction of implanted coils is common in the follow up period. Such retraction may be related to spontaneous closure of residual shunt after embolisation.

Stretched minimal diameter of the ductus and coil occlusion

BACKGROUND

Stretching of the ductus was supposed to determine the size mismatch of the coil with the ductus in coil occlusion that results in residual leak or migration.

METHODS

We measured the minimal diameter (D) and the stretched minimal diameter (S) of the ductus in 12 patients with patent ductus arteriosus (PDA). The stretch index (SI) was calculated as S divided by D. We calculated ratios of the loop diameter of the first implanted coil to D (C1/D) and S (C1/S) and those of the sum of all the loop diameters of all implanted coils for complete closure to D (total C/D) and to S (total C/S).

RESULTS

Stretched minimal diameter divided by D was 1.8 +/- 0.3. Ratios of the loop diameter of the first implanted coil to D (C1/D), and S (C1/S) were 3.7 +/- 1.8 and 2.1 +/- 0.9, respectively. Ratios of the sum of all the loop diameters of all coils to D (total C/D) and S (total C/S) were 5.2 +/- 1.6 and 2.9 +/- 0.9, respectively. Standard deviations of C1/S and total C/S are significantly smaller than those of C1/D and total C/D, respectively.

CONCLUSIONS

The narrowest segment of the ductus could be stretched to twice the size of the minimal diameter. The stretched minimal diameter may be a more reliable parameter to select the loop diameter of coils than the angiographic minimal diameter.

Transvenous "snare-assisted" coil occlusion of patent ductus arteriosus

Sixty consecutive patients underwent successful transcatheter closure of patent ductus arteriosus without morbidity using a modified transvenous "snare-assisted" approach and a single elongated Gianturco coil. This technique ensures complete occlusion and avoids inadvertent embolization of the coil to undesirable sites, making transcatheter occlusion a viable alternative to surgical ligation.