PIVOTAL Compares EVAR and Surveillance of Small AAAs

April 27, 2010—The Society for Vascular Surgery announced publication of the PIVOTAL (Positive Impact of Endovascular Options for Treating Aneurysms Early) study. PIVOTAL found that both early treatment with endovascular repair and rigorous surveillance with selective aneurysm treatment as indicated appear to be safe alternatives for patients with small abdominal aortic aneurysms (AAAs), protecting the patient from rupture or aneurysm-related death for at least 3 years. Kenneth Ouriel, MD, et al published the study in the Journal of Vascular Surgery (2010;51:1081–1087).

Medtronic, Inc. (Minneapolis, MN) sponsored the open-label study, which used the company's AneuRx AAA stent graft and Talent AAA stent graft. Dr. Ouriel first presented the data in September at the 2009 Transcatheter Cardiovascular Therapeutics scientific sessions in San Francisco, which was previously reported by Endovascular Today

According to the investigators, repair of large AAAs is well accepted, but randomized clinical trials have failed to demonstrate benefit for early surgical repair of small aneurysms over surveillance. Dr. Ouriel stated, “Even though endovascular repair has been demonstrated to be safer than open surgical repair in patients with large aneurysms, our team of researchers wanted to do a randomized trial of early endovascular repair vs. surveillance in patients with small aneurysms.”

In the study, a total of 728 patients with small infrarenal aneurysms (4 to 5 cm in diameter) were found on computed tomography scan up to 3 months after a screening of 4,665 patients. The two groups were randomly assigned to either early endovascular repair (366) or ultrasound surveillance (362). Of the repair patients, 322 had an endograft and four had open surgery (99.7% success rate). In the ultrasound surveillance group, 109 patients had to have an endograft and three had open surgery; 70.6% of these procedures were due to the growth of the AAA. The mean age of the patients was 71 ± 8 years and approximately 13% were women. Rupture or aneurysm-related death and overall mortality were compared in the two groups during a mean follow-up of 20 ± 12 months (range, 0–41 months).

The findings showed that there were 15 deaths in each group (4.1%) and the unadjusted hazard ratio for mortality after early endovascular repair was 1.01 (0.49, 2.07; P = .98). Aneurysm rupture or aneurysm-related death occurred in two patients in each group (0.6%). The unadjusted hazard ratio was 0.99 (0.14, 7.06; P = .99) for early endovascular repair.

“Treatment decisions for an individual patient are based on weighing the estimated risk of rupture against the risk or repair estimated risk of death from treatment,” said Dr. Ouriel. “In our study we sought to clarify the distinction between small and large aneurysms. Until longer follow-up data from this study are available, early treatment with EVAR and image-based surveillance, and aneurysm treatment as clinically indicated, both appear to be safe alternatives for patients with small aneurysms of 4 to 5 cm.”

The investigators noted that this recommendation is based on early data that might change as longer-term data accrue and that the findings must be taken in the context of the very low operative mortality rate after EVAR performed by the experienced trial surgeons and the diligence of the follow-up in the surveillance-only patients.

“In addition, patients who are noncompliant with imaging protocols comprise a particularly challenging subgroup for whom neither surveillance with selected repair, endovascular repair, and not even open surgery provide a safe option,” added Dr. Ouriel. “Efforts for this subgroup should be directed at education and active tactics to encourage follow-up imaging studies. For now decisions should be individualized and based on the size of the aneurysm, the medical condition of the patient, the likelihood of patient following a rigorous surveillance protocol and the surgeon's expertise in EVAR.”