Intraaortic spring coil loops: early and late results

Long-term follow-up results of lung perfusion studies after transcatheter closure of patent ductus arteriosus

OBJECTIVE

This study presents the long-term follow-up of patients who developed left lung perfusion (LLP) abnormalities following patent ductus arteriosus (PDA) closure with various device types.

DESIGN

The study includes 23 adult and pediatric patients who had undergone transcatheter PDA closure and were shown to have decreased LLP (<40%) by the first scintigraphy performed within the average follow-up period of 14.0 ± 8.12 months (2.0-30 months). For PDA closure, the Amplatzer duct occluder was used in 12 patients, and coils were used in 11. Within the average period of 58.91 ± 12.93 months (37-85 months) after transcatheter PDA closure, a second lung perfusion scintigraphy was performed.

RESULTS

In 13 out of 23 patients (56.5%), LLP improved by the time of the second scintigraphy. Improved and unimproved patients did not differ with regard to age, weight, body surface area, PDA diameter, ampulla diameter, and PDA length at the time of PDA closure and the second scintigraphy. There was no significant difference with regard to the percent of improved patients between the different device types (P =.88). The left pulmonary artery indexes were also insignificantly different (P =.446). Patients with persistent LLP abnormality had significantly higher average Doppler velocity index [(LPA blood flow velocity--RPA blood flow velocity) / MPA blood flow velocity] × 100 (P =.007) and PDA diameter/length. If Doppler velocity index ≥50% is taken as the cutoff value, it is possible to predict persisting LLP abnormality with 80% sensitivity and 76% specificity. Left lung perfusion abnormality was found to persist in patients with PDA diameter/length ≥0.5 with 80% sensitivity and 92.3% specificity.

CONCLUSIONS

The LLP abnormalities seen after PDA closure with various devices eventually improve to normal in the majority of patients during long-term follow-up. Patients whose PDA length is shorter than its diameter are at risk of developing LLP abnormalities that persist long-term.

New device for percutaneous closure of aortopulmonary collaterals

A 4.5-month-old infant with tetralogy of Fallot, pulmonary atresia, and multiple aortopulmonary collaterals underwent successful occlusion of the collaterals using a new device. This new plug (Amplatzer vascular plug) is a self-expandable cylindrical device made of nitinol wire mesh. The device is available in sizes from 4 to 16 mm in 2 mm increment. The device can be used in patients with aortopulmonary collaterals, pulmonary arteriovenous malformations, venovenous collaterals, shunts, coronary fistulas, and certain type of patent ductus arteriosus.

The modern approach to patent ductus arteriosus treatment: complementary roles of video-assisted thoracoscopic surgery and interventional cardiology coil occlusion

BACKGROUND

In an effort to analyze our experience and develop treatment guidelines, we reviewed all our patients with patent ductus arteriosus (PDA) treated with video-assisted thoracoscopic surgery (VATS) or interventional cardiology coil occlusion.

METHODS

One hundred patients underwent 102 cardiac catheterizations. Forty-five children underwent VATS. The entire cohort of patients is 141 because 4 patients underwent both catheterization and VATS.

RESULTS

Successful PDA coil occlusion occurred in 91 patients (91 of 100; 91%); 8 had unsuccessful attempts at coil occlusion and 1 was referred for surgical ligation after catheterization without any attempt at coil placement. Thirty-nine children had successful VATS PDA closure. Six children required conversion to thoracotomy because of inadequate exposure during VATS. Hospital stay for children more than 45 days of age was as follows: VATS median stay, 1 day, mean, 1.4 days; thoracotomy median stay, 4 days, mean, 4.6 days. One patient treated with PDA coil occlusion developed a recurrent PDA and required reembolization. Three children underwent initial catheterization without successful coil placement with subsequent successful VATS. All VATS patients left the operating theater with echocardiography documenting no residual PDA. Two children who underwent successful VATS with no residual PDA at hospital discharge were found on outpatient follow-up to have developed tiny recurrent PDAs and both were successfully coil occluded; 1 of these 2 children is 1 of the 3 children initially evaluated by catheterization and then referred for VATS.

CONCLUSIONS

Video-assisted thoracoscopic surgery and coil occlusion represent complementary techniques for PDA treatment. A rationale for selection of the appropriate treatment modality can be based upon the size and age of the patient and the size and morphology of the PDA.

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.

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.

[Guidelines of clinical practice of the Spanish Society of Cardiology. Requirements and equipment of invasive techniques in pediatric cardiology: clinical application]

Invasive techniques in pediatric cardiology have experienced a big change since the 80's. The growth of non-invasive methods for diagnosing congenital heart defects has made the number of diagnostic catheterizations decrease remarkably. On the other hand, the notable development of pediatric interventional catheterization techniques will allow that, in the near future, the number of therapeutic catheterizations overcomes the diagnostic ones in our country. The former are more difficult and dangerous, so they require experienced and skilled hands and more economic resources. This chapter is divided in three main sections: I) Requirements and equipment needed for pediatric invasive techniques; II) Current indications, contraindications and complications of the diagnostic catheterization, and III) Techniques, indications and results of pediatric therapeutic catheterization: current state. Likewise, we state the suitability or not for these therapeutic procedures in different cardiac anomalies.

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.

Percutaneous coil occlusion of ascending aorta to pulmonary artery shunts

Two patients with pulmonary atresia and intact ventricular septum each underwent early palliative surgery with a pulmonary valvotomy and an ascending aorta to pulmonary artery shunt. Adequate right ventricular growth and relief of pulmonary stenosis rendered the shunts unnecessary. The shunts were successfully occluded percutaneously with Gianturco coils.

Experimental study of coil embolization using a new atelocollagen spring coil

Spring steel coils have been used to occlude abnormal vessels in patients with a congenital heart malformation. However, long-term adverse effects of steel spring coils remain uncertain, although some long-term results appear to be good. The purpose of this study was to evaluate the angiographic and histologic results of coil embolization experimentally using a biodegradable atelocollagen coil that we have recently developed. The spring coil was made from a 30% atelocollagen solution mixed with a contrast medium. The delivery system consisted of a 5-F end-hole catheter and a 3-F modified biotome catheter as a catch and release system. Coil embolization was percutaneously attempted in 12 dogs, and only one coil was placed in each dog so that a variety of endothelial coverage could be evaluated both in complete and incomplete occlusion. At 1 wk to 5 mo after the procedure, the occluded vessels were resected and examined histologically. Postprocedural angiography showed complete occlusion in 6 of the 12 vessels and partial occlusion in 6. Follow-up angiography showed complete occlusion in 8 and incomplete occlusion in 4. Histologic examination revealed that diffuse thrombosis around the coil loops and the exchange between blood and contrast medium were detectable as early as 7 d after embolization. Atelocollagen was gradually replaced with fibrous tissue and became markedly degraded by 5 mo. Atelocollagen spring coils can be used to occlude abnormal vessel effectively and safely. The histologic reactions and the fate of the coil seem to be within tolerable limits. This experimental study supports the feasibility of a clinical trial of this coil embolization in patients with an aorticopulmonary collateral artery.

Coarctation of the aorta following coil occlusion of a patent ductus arteriosus

A case is described in which coarctation of the aorta develops following coil occlusion of a patent ductus arteriosus with a single Gianturco coil. This finding has yet to be reported in children undergoing this procedure and demonstrates the possibility of its occurrence and brings into question the need for and the duration of antibiotic prophylaxis following coil deployment.

Effectiveness of five-loop coils to occlude patent ductus arteriosus

Coil occlusion of patent ductus arteriosus with 5-loop coils was undertaken in 10 patients without coil embolizations, and with 90% immediate occlusion and 100% occlusion at follow-up. We conclude that 5-loop coil occlusion of patent ductus arteriosus is safe and effective.

Transcatheter occlusion of patent ductus arteriosus using coil embolization

We studied 31 procedures of coil embolization for occlusion of ductus arteriosus, attempted in 29 patients. The mean age was 4.8+/-3.4 years (1-16 years) and the mean diameter of ductus was 1.8+/-0.7 mm (0.8-3.1 mm). Femoral artery approach was used and aortogram in 90 degrees lateral view was performed. Through a Judkin right coronary catheter, the coil was delivered for occlusion of the ductus. In 5 cases, 2 coils were delivered using retrograde and anterograde techniques. Successful placement of coil was accomplished in 29 procedures. Coils 0.038 inch (diameter)-5 cm (length)-5 mm (helical diameter) (Cook, Inc) were used in 16 procedures, coils 0.035 inch-5 cm-5 mm in 9, coil 0.038 inch-8 cm-8 mm in 1, two coils 0.038 inch-5 cm-5 mm in 2, coils 0.038 inch-5 cm-5 mm+0.038 inch-5 cm-8 mm in 1, and 2 coils 0.035 inch-5 cm-5 mm in 2. Aortogram 20 min after the occlusion, showed residual shunt in 9. Coil migration occurred in a ductus type B in the following day. One patient developed severe haemolysis, due to a change in the coil position, 12 h after the procedure. Echodopplercardiogram 4 to 6 h after the procedure showed a residual shunt in 5 patients, 24 h after in 3 and 30 days after, in 1(3.8%). Heparin therapy started 10 days after occlusion of the ductus, caused reappearance of the shunt in 1 patient. This technique is simple and effective, but complications may occur hours or days after successful ductus occlusion.

Percutaneous therapy of structural heart disease: pediatric disease

Interventional therapy of congenital heart lesions at cardiac catheterization has greatly increased during the past decade. At the authors' institution, the frequency of such procedures among catheterizations has increased from 5% to more than 60%. The variety of lesions so treated continues to expand and equipment continues to improve. These procedures may be divided into 2 groups, namely (1) those involving balloon dilation of stenotic valves and vessel obstructions with stent placement being increasingly used in the latter and (2) those involving occlusion of lesions with (a) coils, such as aortopulmonary collaterals, patent ductus arteriosi and coronary artery fistulae and (b) umbrella devices, such as atrial and ventricular septal defects. These have replaced surgery as the initial procedure of choice in many lesions including valvar pulmonary and aortic stenoses, and postoperative aortic coarctation in young patients. In addition, use of the double-umbrella device even in noncongenital lesions appears promising.

Percutaneous coil occlusion of patent ductus arteriosus

OBJECTIVE

To determine the success rate and safety of percutaneous patient ductus arteriosus (PDA) coll occlusion.

DESIGN

Thirty consecutive pediatric patients with small to moderate-size PDAs (minimum diameter < or = 4 mm) underwent percutaneous coll occlusion. The results were assessed by angiography and echocardiography. The mean age was 5.1 +/- 4.2 years (range, 0.8 to 18.8 years); mean weight was 19.2 +/- 10.3 kg (range, 8.1 to 40.0 kg). The mean minimum diameter of the PDA was 1.8 +/- 0.8 mm (range, 1.0 to 4.0 mm).

RESULTS

PDA occlusion was achieved with one coil in 24 patients, 2 coils in 3 patients and 3 coils in 3 patients. The mean coil/PDA diameter ratio was 2.5 +/- 0.5. Immediately after coil occlusion, 29 PDAs had no flow by anglography; one had a small residual shunt. There were no significant complications. In the first 24 hours after coil implantation, echocardiography showed complete occlusion in 28 patients, a small left-to-right shunt in the same patient that had a residual shunt by anglography, and a trace shunt in one additional patient. In the two patients with residual flow by echocardiography, follow-up ultrasonography revealed no residual shunt 1 and 3 months later. At a mean follow-up of 11.8 +/- 9.3 months (range, 0 to 36.0 months), there was no PDA flow by color Doppler echocardiography in any of the 30 patients.

CONCLUSION

Coil occlusion is a safe and effective method of percutaneous closure of small to moderate-size PDAs. The largest PDA that can be closed with this technique remains to be determined.

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.