Endovascular or endograft repair for abdominal aortic aneurysms (AAA) has low re-intervention rates that are comparable to those reported for open surgical repair--and can be recommended as first-line treatment, according to research presented at the the Society of Interventional Radiology (SIR) annual conference this week in San Diego.
Currently this less invasive treatment has been reserved for elderly patients or those with co-morbid conditions who were considered too sick for major surgery.
"Our data show that the interventional radiology treatment can be chosen with confidence. This is good news for patients, many of whom do not want major abdominal surgery," said Tarun Sabharwal, MD, interventional radiologist at Guy's and St. Thomas' Hospitals in London. Additionally, the researchers advocated revising current surveillance of patients' stent grafts by CT scans to check for delayed appearance of complications, especially in light of the added radiation risk the scans bring to patients.
AAA, dubbed the "silent killer" because there are usually no obvious symptoms of the disease, is the 17th leading cause of death in the United States, accounting for more than 15,000 deaths annually. AAA affects as many as 8 percent of people over the age of 60, and men are four times more likely to have AAA than women.
Interventional radiologists analyzed the results of 453 patients who underwent endovascular repair for AAA over an eight-year period, studying the rate of secondary interventions (or the necessity of performing additional procedures to correct complications from a prior treatment) and whether the need for repeat interventions could be predicted by surveillance imaging.
"Most importantly, the overall rate of secondary interventions after endovascular repair was 7.2 percent, which compares favorably to open surgery series," said Sabharwal.
Complications include possible movement of the graft after treatment or persistent blood flow into the aneurysm, which resumes the risk of its growth or rupture. Also, the graft must be monitored to ensure its continued function, and endoleaks may occur, causing blood to flow outside the endovascular graft.
Researchers noted that 2.8 percent needed to be treated for this latter complication. The overall 30-day mortality rate for endovascular aneurysm repair was 3.3 percent, compared to open surgery, which has a high associated mortality rate. Additionally, researchers found that most complications were detected within the first three months after repair, and that it was "rare" for CT scans to detect complications after that period of time.
"This suggests that CT surveillance protocols are not justified; if a three-month surveillance scan doesn't demonstrate any abnormalities, then patients could be followed with routine ultrasound scanning to monitor for complications," he added. In total, secondary interventions were performed in 33 patients, of which six were CT scan surveillance detected.
"Our results, following patients over the past eight years, contradict reports of high rates of secondary interventions coupled with the need for prolonged CT scan surveillance," he said. "Endovascular repair reduces the risk of surgery, the amount of pain and the number of complications, getting patients back to normal health more quickly than surgery. Its recovery time is measured in days to weeks, as opposed to surgery patients who take several weeks to months to recover."