ABSTRACT
RATIONALE AND OBJECTIVES: The clinically most widely used devices (Porstmann-plug, Rashkind-umbrella, Botallooccluder) have inherent specific limitations (eg, transarterial approach, residual shunts, limited retrieval). The authors assess practicability, efficacy, and tissue reaction of the new retrievable transvenous plug device for the occlusion of the persistent patent ductus arteriosus (PDA). METHODS: A foam plug (polyvinyl alcohol) is mounted on a titanium core pin where, at both ends, small legs (titanium nickel alloy) with titanium heads are anchored, to ensure safe fixation in the ductus. The device is introduced transvenously through a long sheath (Mullins sheath) and held by a modified biopsy forceps allowing complete retrieval until final release. A common lamb model of large PDAs (n = 11) was used to test for practicability and the histomorphologic outcome. Clinical results were obtained from a consecutive series of 16 patients (aged 13 to 71 years). RESULTS: In all lambs, placement of the plug within the PDA was possible. Histopathology (follow-up 10 to 215 days; mean 112 days) revealed an adequate ingrowing of the device and no pathologic foreign body reaction. The diameter of the human PDAs ranged from 3 to 7 mm (mean 5 mm). The size of the sheath used for introducing the plug (diameter 8 to 16 mm) ranged from 8 to 16 French. Fourteen of 16 PDAs were closed immediately after or on day 1 after implantation, 1 was closed after the 12-month follow-up, and 1 needed an additional plug after 30 months for definitive closure. CONCLUSIONS: The device demonstrated practicability and biocompatibility in our experimental lamb model and effectively closed the PDA in a consecutive series of 16 patients. A greater number of patients and a longer follow-up period are necessary for the definitive clinical assessment of the new device.
Subject(s)
Ductus Arteriosus, Patent/therapy , Embolization, Therapeutic/methods , Polyvinyls/therapeutic use , Adolescent , Adult , Aged , Animals , Animals, Newborn , Aortography , Ductus Arteriosus, Patent/diagnostic imaging , Ductus Arteriosus, Patent/pathology , Embolization, Therapeutic/instrumentation , Female , Follow-Up Studies , Humans , Male , Microscopy, Electron, Scanning , Middle Aged , Sheep , Treatment OutcomeABSTRACT
An Ivalon-plug (PDA-plug) has been developed for transvenous closure of patent ductus arteriosus. It can be introduced into the ductus through standard venous sheaths with a diameter of 8-16 French. The plug is fixed in its target position by means of four distal (aortal) and two proximal (pulmonary) nitinol struts. In case of malpositioning the system can be pulled back into and retrieved through the sheath. In animal experiments endothelialization of the implanted material was demonstrated. PDA-closure was attempted in 58 patient; the procedure was successful in 57 cases; a residual ductal flow was present in eight patients. During a follow-up of up to 24 months there were no complications.
