'In vivo' size of knitted Dacron prostheses (Gelseal) used in the thoracic aorta: a computed tomography study

Long-term size follow-up of knitted Dacron grafts (Gelseal™) used in the ascending aorta

There is limited information about the size change of a knitted Dacron graft (Gelseal™) used in the thoracic aorta. We evaluated the diameters of the Gelseal™ grafts at a long-term follow-up for 3.7 ± 1.3 years (1-5.9 years; median, 4.0 years), which were used for replacement of the ascending aorta in 59 patients with acute aortic dissection. The early and late dilatation rates (LDRs) of the prosthetic grafts were calculated retrospectively based on the graft diameter at the level equivalent to the ascending aorta on the pre-discharge computed tomography (CT) scans and follow-up CT scans performed every year after surgery. Immediately after surgery (15 ± 7 days), the early dilatation of the Gelseal™ grafts was 26.0 ± 6.0% with significant correlations with the number of post-operative days (R = 0.500, P = 0.003). At the follow-up for 3.7 ± 1.3 years, the LDR was 10.5 ± 6.6%, which was also significantly correlated with the number of the post-operative years (R = 0.608, P = 0.001). Linear regression analysis indicated that the annual dilatation rate was ≈ 3.23%. During the follow-up, we have experienced no redo surgery due to graft fracture or false aneurysm formation at the anastomosis sites associated with the graft dilatation. In conclusion, the Gelseal™ graft used in the ascending aorta demonstrates a small but continuous increase in the diameter, up to 5 years after implantation, without any adverse events.

Dilatation of aortic grafts over time: what to expect and when to be concerned

Dilatation of aortic prosthetic grafts is commonly reported, but most reports are anecdotal, with little objective data in the literature. We performed a prospective trial of 303 patients who underwent prosthetic graft repair for aortic aneurysm or occlusive disease, randomizing patients between insertion of a woven polyester or expanded polytetrafluoroethylene (ePTFE) graft. Patients were followed with computed tomography and ultrasonography for up to 5 years in order to assess the frequency and magnitude of postoperative dilatation. Graft dilatation was documented in patients with polyester grafts at 12 months. Thereafter and up to 60 months, polyester grafts did not dilate further. After 5 years, polyester prostheses had dilated by 25% and ePTFE by 12.5%, as determined by computed tomography imaging. These observations suggest that dilatation of prosthetic grafts is more frequent with knitted polyester grafts compared with ePTFE. Dilatation occurs within the first year after implantation and can be, in part, explained by a discrepancy between the initial nominal graft diameter and its diameter after clamp release, probably due to an in vivo adaptation of the textile structure. Interestingly, graft dilatation did not appear to be associated with an increased frequency of graft-related complications.

Behaviour of polyester grafts in adult patients with repaired coarctation of the aorta

AIMS

Whatever the technique used for surgical or endovascular repair of a coarctation of the aorta (CA), long-term complications might occur. Aneurysm formation after patch angioplasty is not uncommon and may lead to a life-threatening condition. Therefore, we were interested in the long-term results of different types of tube grafts, from which a lower degree of dilatation is expected.

METHODS AND RESULTS

All patients, currently older than 16 years, who underwent (redo) surgery for CA, and in whom a tube graft was inserted, were selected from the database of congenital heart disease of our hospital. Follow-up data were collected by reviewing the patients' files. The degree of graft dilatation was calculated for each patient. Fifty-three patients (41 males, median age 33.1 years, Q1-Q3 29.9-40.2 years) could be included in the study, in which 20 (38%) 'Gelseal', 12 (23%) 'Gelsoft', 8 (15%) 'Gelweave', and 13 (24%) older types of grafts were used. Twenty patients underwent a primary repair and in all others a tube graft was implanted after a previous patch angioplasty. The median graft diameter (manufacturer size) at implantation was 20 mm (Q1-Q3 16-22 mm). The median follow-up time of the grafts was 13.1 years (Q1-Q3 9.0-17.2 years). The graft size increased to a median value of 26 mm (Q1-Q3 22-30 mm) (median 50% increase in diameter, range 0-271%, P < 0.0001). The diameter of six grafts remained unchanged during follow-up. Three deaths occurred, of whom two were cardiac-related. False aneurysms occurred in four patients, graft aneurysm in two, endarteritis in two, and graft stenosis in one.

CONCLUSION

Nearly, all tube grafts dilated up to 50% of the manufacturer diameter during follow-up. Re-interventions were inevitable in more than 10 per cent of the cases, primarily because of (false) aneurysm formation. Our series illustrates that late complications are not uncommon, so that rigorous follow-up of these CA patients remains mandatory.

Gelseal versus Gelweave dacron prosthetic grafts in the descending thoracic aorta: a two-year computed tomography scan follow-up study

BACKGROUND

In the abdominal aorta, the use of knitted rather than woven dacron prostheses has shown an early and slow late dilation. The dilation of woven versus knitted dacron prostheses in the thoracic aortic position has not yet been investigated.

METHOD

From 1992, 25 patients entered a prospective study: 13 Gelweave and 12 Gelseal prostheses (diameter 18-26 mm) were implanted in the descending thoracic aorta. Computed tomography (CT) scans without contrast-enhancement were performed 2 weeks, and 1 and 2 years postoperatively. The full length of the grafts was scanned and the diameter was measured in mm measured at a level outside the areas of intercostal artery reimplantation. Patient determinants analysed were age, hypertension and implantation diameter of the grafts. The Gelseal group had a mean age of 63.7 years and seven were males. The Gelweave group had a mean age of 67.8 years and seven were males.

RESULTS

the mean implantation diameters were 19.6 +/- 1.7 mm and 22.0 +/- 2.7 mm (P = 0.02) for the Gelseal and Gelweave grafts, respectively. On the CT-scans at 2 weeks postoperatively, the diameter had increased by 18.8 +/- 4.8% (P = 0.0001) in the Gelseal and by 5.7 +/- 6.4% (P = 0.007) in the Gelweave grafts. This difference in diameter at 2 weeks between the two prostheses was significant (P < 0.0000 1). At 1 year the diameter had increased by 28.4 +/- 5.2% (P = 0.0001) and by 8.4 +/- 4.6% (P = 0.0003) for the Gelseal and Gelweave grafts, respectively, compared with the implantation diameter. The increase in diameter between the postoperative values at 2 weeks and those at 1 year was statistically significant in the Gelseal grafts (P = 0.0002) but not in the Gelweave grafts (P = 0.56). At 2 years an increase in diameter by 31.4 +/- 5.2% (P = 0.0001) and by 7.4 +/- 7.1% (P = 0.014) for the knitted and woven prosthetic grafts, respectively, was noted compared with the initial implantation diameter. The increase in diameter between the CT measurements at 2 weeks and those at 2 years was statistically significant in the Gelseal group (P = 0.001) but not in the Gelweave group (P = 0.86). The difference in this late increase in diameter between the two implanted grafts was also significant (P < 0.005). Age, hypertension and initial diameter did not appear to be significant determinants.

CONCLUSION

In contrast to the Gelseal prosthesis in the descending aorta, the Gelweave prosthesis does not show any late dilation.