Clinical application of the coil-sack vascular occlusion device in infants and children

Experimental evaluation of a new transcatheter vascular embolization device in the swine model

PURPOSE

To evaluate a new transcatheter device suitable for arterial embolization in an animal model.

MATERIALS AND METHODS

A new prototype self-expanding braided embolic device (Embolizor), consisting of nitinol wire strands fixed at either end with platinum-iridium bands and covered with a film of polyethylene, was deployed through 5-F diagnostic catheters into renal artery branches in five swine. Standard stainless-steel spring coils were deployed in other renal branches and served as controls. The animals underwent follow-up selective renal arteriography to determine presence or absence of vessel recanalization or device migration 15-23 days after device deployment. Histopathologic evaluation of target vessels and peripheral renal parenchyma was also performed.

RESULTS

Ten Embolizors and 10 stainless-steel coils were deployed in arteries ranging in size from 1.8 to 3.0 mm in diameter. The Embolizor was easily and precisely deployed. Angiographic evidence of vascular occlusion in the Embolizor group was noted within 30 seconds in eight device deployments and within 5 minutes in two. No early or delayed device migration was noted on follow-up arteriography. In the control group, seven of 10 previously occluded arteries were recanalized. No recanalization was noted in the Embolizor group. Light microscopy revealed evidence of infarction in all specimens examined. Whereas three specimens in the Embolizor group contained occasional giant cells, there were numerous multinucleated giant cells present within the interstices of all control spring coils.

CONCLUSION

The Embolizor was easily, precisely, and successfully deployed through standard selective diagnostic angiographic catheters. Short-term follow-up demonstrated no recanalization or migration of the device. The Embolizor was shown on histopathologic analysis to have no significant foreign body reaction.

[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.

Right aortic arch with isolation of the left subclavian artery, moderate patent ductus arteriosus, and subclavian steal syndrome: A rare aortic arch anomaly treated with the Gianturco-Grifka vascular occlusion device

We present the first described use of the Gianturco-Grifka Vascular Occlusion Device to close a moderate patent ductus arteriosus associated with the rare congenital condition of right aortic arch with isolation of the left subclavian artery. Left vertebral artery "steal" through the moderate patent ductus arteriosus was eliminated by this transcatheter technique. Cathet. Cardiovasc. Intervent. 47:320-322, 1999.

[Interventions in congenital heart disease and their sequelae in adults]

The advancements of cardiac surgery over the last decades led to larger numbers of patients with operated congenital heart diseases surviving into adulthood. In Germany it is estimated that over 120,000 adults have operated congenital heart diseases. Five to 7% of them will need yearly hospital admissions. Interventional procedures are additional tools used to treat these patients with various sequelae or residua (Table 1). In the following review we concentrate on 2 different interventional procedures: dilatation and stent implantations for treatment of stenosis and the different devices used for the closure of shunt lesions. For congenital valvular pulmonary stenosis, balloon dilatation is the therapy of choice regardless the age of the patient. Stent implantation for the treatment of peripheral pulmonary stenosis (e.g., after previous systemic pulmonary shunts) can decrease the need for redo surgery, which is accompanied with increased risk. Stent implantations proved also to be useful to treat stenoses after Mustard patch in patients with transposition of the great arteries, after Fontan procedures or dealing with the rare pulmonary venous stenosis. In contrast, dilatation of bioprosthesis and conduit stenosis are not promising. Balloon dilatation of valvular aortic stenosis is an accepted therapy in childhood up to adolescents. Table 2 compares a surgical series including many infants with critical aortic stenosis with a series of balloon dilatation in children and another one in adults regarding lethality, complications, and results. Table 3 illustrates the immediate and late results of balloon dilatation of aortic coarctation in 3 different studies. The high recurrence rate in infants made clinicians refrain from taking this age group for balloon dilatation. In children and adult patients, good results are reported (75% reduction of gradients). The complication rate is low (2.3 to 3.3%) and aneurysm formation rate seldom (1 to 7%). Stenosed aorto-pulmonary collaterals will rarely need balloon dilatation. Surgical closure of atrial septal defect is a low risk procedure with a very low rate of residual shunts (2%). Of the 5 available devices for transcatheter closure of atrial septal defect Type II, only 2 occluders are in use in Germany, the Clamshell and the Amplatzer device. The largest clinical studies of the different systems, their efficacy, complications and residual shunt rate are presented in Table 4. For the deployment of these occluders a TEE is always needed. There are many more systems in clinical use to close the patent arterial duct (PDA) (Table 5). The Ivalon plug as well as the Rashkind device have probably only historical value. Different types of coils (Gianturco, Cook detachable, PFM) are now in use worldwide. The reason for their widespread use, besides their easy application, is the fact that most coils are relatively cheap and need only small sheaths for deployment. Their further evaluation identified a residual shunt rate of 5% as well as a number of complications (embolization, hemolysis, stenosis of the left pulmonary artery) in 0 to 6%. For the large PDA the Amplatzer device has recently been introduced. An additional indication for the use of the different occluding devices are aorto-pulmonary collaterals, venovenous fistulae, pulmonary or coronary artery fistulae. Aorto-pulmonary collaterals are often associated with complex cardiac lesions and occasionally appear after palliative procedures. An excellent cooperation between adult and pediatric cardiologists is needed in order to offer the group of adults with congenital heart diseases an adequate and comprehensive management.