Zenith abdominal aortic aneurysm endovascular graft

Enrollment in the United States Zenith Multicenter Trial (ZMT). The pivotal portion of the trial included 80 surgical controls, 200 standard-risk endovascular patients, 100 high-risk endovascular patients, and 52 patients allocated to the roll-in arm. After pivotal enrollment was completed, continued access was provided through a separate study arm. At the conclusion of the 2-year follow-up, pivotal patients were given the opportunity to participate in an extended follow-up study carrying out annual assessments through 5 years. The various categories of the trial resulted in three fundamental patient groups: surgical controls, standard-risk endovascular, and high-risk endovascular. For analysis purposes, the roll-in, pivotal study, and continued access groups were combined into conglomerate standard- and high-risk endovascular groups, with a variable degree of follow-up. This flow chart shows enrollment and follow-up details. AAA, Abdominal aortic aneurysm.

Kaplan-Meier graph shows mortality stratified by standard-risk (black line) and high-risk (red line) physiologic groups. Error bars represent 95% confidence intervals at each time point.

The incidence of both new and persistent endoleaks by type and time of onset is shown for high-risk (red) and standard-risk (black) groups. The Kaplan-Meier plot shows the cumulative risk for a late endoleak of any type. Error bars represent 95% confidence intervals at each time point. No statistical differences were noted between the high- and standard-risk groups, although the numbers of patients at late follow-up time points were relatively small.