Endovascular repair of abdominal aortic aneurysms showed a higher mortality rate over the long term compared with open surgical repair, according to a study published yesterday in The Lancet.
The study, “Endovascular versus open repair of abdominal aortic aneurysm in 15-years’ follow-up of the UK endovascular aneurysm repair trial 1,” was based on data from the 1,252-patient Evar trial 1, in which 626 patients were randomly assigned to either EVAR using a stent graft or open surgical repair. The primary endpoint was total and aneurysm-related deaths through mid-2015.
The EVAR cohort showed a 42% lower mortality rate after 6 months, likely due to lower complication rates. There was no mortality difference between the techniques from 6 months to 8 years, but from 8 to 15 years the EVAR group showed a 14% mortality increase compared with the open surgery group.
“The increased aneurysm-related mortality in the EVAR group after 8 years was mainly attributable to secondary aneurysm sac rupture (13 deaths [7%] in EVAR vs two [1%] in open repair), with increased cancer mortality also observed in the EVAR group,” the authors wrote.
Lead author Dr. Roger Greenhalgh, of the Imperial College London, said aneurysms in the EVAR group could refill if the stent graft slips over time as patients’ blood vessels widen with age.
“What appears to be happening is that the device inserted into the aorta can move slightly over time. This allows tiny leaks to occur. Over time, these leaks cause a pressure build-up in the original aneurysm, which is then at risk of bursting. However, if patients were regularly scanned, these aneurysms could be caught in time,” Greenhalgh said.
Although newer stent grafts and 3D imaging have improved EVAR since the study launched in 2004, regular screening is a must, he added.
“These findings need to be a wake-up call to doctors across the world. Many of these aneurysms could have been caught with regularly scanning, such as ultrasound scanning. Therefore we should be scanning patients who undergo the EVAR procedure at least once a year, rather than the current situation where patients receive scans far less often,” Greenhalgh said. “The vast majority of aneurysm repairs performed in the world are EVAR procedures, and we are certainly not recommending switching back to the open operation. This involves a large incision in the body and carries serious risks.”
