Late Aortic Remodeling Persists in the Stented Segment After Endovascular Repair of Acute Complicated Type B Aortic Dissection

Abstract

Thoracic endovascular aortic repair (TEVAR) for acute complicated type B dissection (cTBD) promotes early positive aortic remodeling. However, little is known about the long-term effect of TEVAR on the dissected aorta, which is the goal of this study. Between August 2005 and August 2009, 31 patients with cTBD were treated with TEVAR and had long-term (>1 year) follow-up imaging. CTA obtained at 1 month (1M), 1 year (1Y), and long-term (LT; average 42 months) were compared with baseline (BL) scans. The largest diameters of the stented thoracic aorta (SMAX), stented true lumen (STL), and stented false lumen (SFL) were recorded at each time point, as were the values in the unstented distal thoracic aorta and the abdominal aorta. Changes over time were evaluated using a mixed effect analysis of variance model of repeated measures. Demographics: age 56 years; 74% male. Indications for TEVAR: 61% malperfusion, 32% refractory hypertension, 45% impending rupture, 32% persistent pain; 58% had >one indication. The average length of aorta covered was 19 cm. Aortic remodeling along the stented segment is summarized in Fig 1. The SMAX remained stable (P = not significant), STL increased (P < .001), and SFL decreased (P < .001) over time; 84% had complete false lumen (FL) obliteration. For the uncovered segment, the maximum diameter increased (P = .014), as did TL (P < .001) and the visceral segment (P < .001). The FL was stable (P = not significant). The average growth of the visceral segment was 31% in patients with a patent FL vs 3% in those without (P = .004). One patient had aneurysmal degeneration of the false lumen and required an additional endograft at 2 years. TEVAR of cTBD promotes long-term remodeling across the stented segment with FL obliteration in 84% of patients. However, FL obliteration beyond the stented segment appears necessary to prevent late aneurysmal degeneration.