Aortic aneurysm sac shrinkage after endovascular repair is device-dependent: A comparison of zenith and AneuRx endografts

Aneurysm sac shrinkage after endovascular aneurysm repair (EAR) provides objective evidence of successful aneurysm exclusion and absence of endotension. Attainment of this outcome parameter may be device-dependent. In this study, 169 patients underwent EAR with an AneuRx (n = 118) or Zenith (n = 51) endograft at a single institution. A prospectively maintained database was examined for significant changes in aneurysm sac diameter (greater than or equal to5 mm) on the basis of computed tomography (CT) measurements at 6 and 12 months follow-up. Significant aneurysm sac shrinkage (greater than or equal to5 mm) occurred in 73.1% (19/26) vs. 43.1% (28/65) of patients in the Zenith and AneuRx groups, respectively, at 12 months (p = 0.03). At 6 months follow-up, sac shrinkage rates were 51.4% (19/37) vs. 25.8% (16/62) in the Zenith and AneuRx groups, respectively (p = 0.04). Mean reduction of sac diameter at 12 months was -7.6 +/- 1.6 mm vs. -3.5 +/- 0.8 mm in the Zenith and AneuRx groups, respectively (p = 0.01). There was a trend toward fewer Type I and III endoleaks at 1 month in the Zenith group (0 vs. 8.3%) that did not achieve statistical significance (p = 0.067). The presence of any endoleak (greater than or equal to1 month) was associated with reduced 12 month shrink rates from 47.1% (25/51) to 28% (4/14) in the AneuRx group (p = 0.35) and from 77.3% (17/22) to 50% (2/4) in the Zenith group (p = 0.25). Patients treated with the Zenith endograft demonstrated a significantly higher rate and amount of aneurysm sac shrinkage than patients treated with an AneuRx device. Endoleaks appeared to negatively influence shrink rates with both endografts.