"Traditionally thoracic aortic aneurysm disease has been treated with surgery requiring a large chest incision and placement of a synthetic graft to repair the artery. However, a new study indicates that use of the minimally invasive W.L. GORE TAG (R) Thoracic Endoprosthesis to treat descending thoracic aneurysms appears to be superior to open surgical repair in anatomically suitable patients.
Investigator Ellen D. Dillavou, MD, from the division of vascular surgery at the University of Pittsburgh Medical Center, said this is the first study to look at the long-term (five-year) outcomes of the two procedures. "Our researchers studied outcomes of the TAG endograft after its implantation in 140 patients compared to 94 patients who had similar aneurysms repaired by open surgery, between September 1999 and May 2001, as well as 51 more patients who were added in 2003 after revision of the endograft." The long-term follow-up of the multi-center device trial which took place at centers throughout the United States, is detailed in the May 2008 issue of the
Journal of Vascular Surgery.Follow-up consisted of patient visits, computed tomography scans and X-rays at one and six months, then annually for five years. "Initially and at five years, TAG patients had better results," said Dr. Dillavou. "At five years aneurysm-related mortality was 2.8 per cent compared to 11.7 per cent in open surgery patients, and major adverse events were 57.9 per cent vs. 78.7 per cent. Endoleaks in TAG patients decreased from 8.1 per cent at one month to 4.3 per cent at five years."
There were no aneurysm ruptures reported in either group over the study period and no deaths due to aneurysm-related causes after one year in either group. At five years, secondary procedures in the TAG group were lower (15.0 per cent vs. 31.9 per cent) and many were managed with a minimally invasive approach. Only five TAG patients underwent major aneurysm-related re-interventions (3.6 per cent), including one arch aneurysm repair, one open aneurysm repair and three patients with minimally invasive procedures for endoleaks.
Dr. Dillavou added that at five years, aneurysm sac size decreased in 50 per cent of the patients and increased in 19 per cent of them, compared to the one-month baseline. Comparison with the modified low-porosity device at two years showed sac increase in 12.9 per cent of original vs. 2.9 per cent in modified grafts. "Although sac enlargement is concerning, early modified device results indicate this issue may be resolved," said Dr. Dillavou.
"Prior to this report it was not known if minimally invasive repairs would be as durable as traditional open repairs," said Dr. Dillavou. "This study demonstrates that in suitable patients, endovascular repair of thoracic aneurysms has clear and lasting advantages over open aneurysm repair and that the TAG endograft is durable to five years of follow-up. This work confirms that the early advantages of minimally invasive endovascular thoracic aneurysm repair extend to five years of follow-up. TAG patients had fewer deaths and complications from their aneurysms, making this the safest approach for suitable patients."