Off-label use of stretchable polytetrafluoroethylene: Overexpansion of synthetic shunts

• Published in: International journal of artificial organs 2010-05, Vol.33 (5), p.263-270
• Main Authors: VERBELEN, Tom O, FAMAEY, Nele, GEWILLIG, Marc, REGA, Filip R, MEYNS, Bart
• Format: Article
• Language: English
• Subjects: Biological and medical sciences; Blood Vessel Prosthesis; Blood Vessel Prosthesis Implantation - adverse effects; Blood Vessel Prosthesis Implantation - instrumentation; Blood Vessel Prosthesis Implantation - mortality; Catheterization - adverse effects; Catheterization - instrumentation; Catheterization - mortality; Child, Preschool; Constriction, Pathologic; Coronary Angiography; Device Approval; Elastic Modulus; Female; Graft Occlusion, Vascular - diagnostic imaging; Graft Occlusion, Vascular - etiology; Graft Occlusion, Vascular - mortality; Graft Occlusion, Vascular - physiopathology; Graft Occlusion, Vascular - therapy; Heart Defects, Congenital - mortality; Heart Defects, Congenital - physiopathology; Heart Defects, Congenital - surgery; Humans; Infant; Infant, Newborn; Male; Medical sciences; Polytetrafluoroethylene; Pressure; Prosthesis Design; Pulmonary Artery - diagnostic imaging; Pulmonary Artery - physiopathology; Pulmonary Artery - surgery; Radiotherapy. Instrumental treatment. Physiotherapy. Reeducation. Rehabilitation, orthophony, crenotherapy. Diet therapy and various other treatments (general aspects); Retrospective Studies; Stents; Time Factors; Treatment Outcome; Vascular Patency
• ISSN: 0391-3988; 1724-6040
• DOI: 10.1177/039139881003300501

To describe our experience with balloon dilatation and stenting of modified systemic-to-pulmonary artery (PA) shunts in relation to an assessment and interpretation of the mechanical properties of thin-walled expandable polytetrafluoroethylene (ePTFE) stretch vascular grafts. Our pediatric cardiology/cardiac surgery database was reviewed to identify all infants and children with a modified systemic-to-PA shunt who underwent cardiac catheterization. Reports and images were reviewed. Thin-walled stretchable and regular Gore-Tex vascular grafts were mechanically compared using tensiometry. 11 patients underwent dilatation or stenting procedures of a systemic-to-PA shunt. No major complications occurred and none of our patients died during or due to this intervention. High pressures in balloons and stents with diameters larger than the graft were used. Shunt diameters and oxygen saturation levels increased from 2.05 +/- 1.25 mm to 4.75 +/- 0.88 mm and with 12 +/- 6.8%, respectively. In 6 patients re-catheterizations were performed. Four patients died, all with patent shunts. The fail-stress and the fail-strain in the circumferential direction of the stretchable graft were significantly higher than in the non-stretchable graft. Dilatation and stenting of stenosed modified systemic-to-PA shunts is feasible and safe. Dilatation and stenting of these shunts to calibers larger than those provided by the manufacturer is possible. Results of our technical study posit a great advantage for the use of the thin-walled stretch configuration of ePTFE.