Portal Vein Embolization using the Amplatzer Vascular Plug II: Preliminary Results

Abstract

In this study we examined the feasibility of portal vein embolization (PVE) by using the Amplatzer Vascular Plug (AVP-II). We measured the time of vessel occlusion after plug deployment and changes in plug length and diameter within 4 weeks of PVE. In 10 consecutive patients (4 women, age 64 +/- 10 yrs, 48 - 82 yrs) an ipsilateral PVE of the right portal vein was performed prior to intended hemihepatectomy. After embolization with microparticles, the right portal vein was occluded using an AVP-II. We measured the time of complete vessel occlusion by angiography. Follow-up with computed tomography (CT) was performed within 72 h and after 4 weeks. PVE was performed in all 10 patients without acute complications. Complete vessel occlusion was achieved in 9.7 +/- 5.1 min (range 1 - 21 min). On follow-up CT we found enhanced arterial vascularization of the embolized liver segments in 5 / 5 patients within 72 hours and in 6 / 10 patients after 4 weeks. The plug showed a contraction of 20 +/- 9 % and a dilatation of 23 +/- 13 %. Thus, the AVP-II dilated to 94 +/- 8 % (78 - 100 %) of its nominal diameter. The plug diameter was significantly larger in men compared to women (17 +/- 1.7 mm vs. 14 +/- 1.4 mm, p < 0.02). We did not observe any recanalization or migration of the device. The volume of the left liver lobe increased significantly by 27 % (p < 0.001) after 4 weeks. PVE with the AVP-II is a feasible and effective method. The AVP-II can dilate within 4 weeks up to its nominal diameter dependent on the grade of oversizing. Dilatation of the diameter is associated with a shortening in length.