Risk Factors for Failed Thoracic Endovascular Aortic Repair: Explant Analysis

OBJECTIVES: To determine relevant risk factors for treatment failure that required endograft explantation in patients undergoing thoracic endovascular aortic repair (TEVAR).
METHODS: All patients undergoing TEVAR from May 2002 to April 2009 were retrospectively reviewed. Treatment failure requiring thoracic endograft explantation was analyzed. Risk factors contributing to treatment failure were assessed.
RESULTS: A total of 315 TEVAR procedures were performed during the study period. Two hundred eighty four patients (TEVAR group) who underwent successful TEVAR procedures and had sufficient follow-up data formed the basis of this analysis. Additionally, 19 patients (explant group) who had TEVAR failure which required thoracic endograft explanation were also included in this study. Among them, 14 patients with TEVAR failures were transferred from outside institutions while five patients with TEVAR failure occurred in our series. Indications for thoracic endograft removal included: endograft infection (n=5), malperfusion (n=7), endograft migration (n=2), aneurysm expansion (n=2), and retrograde aortic dissection (n=3). There were no differences in epidemiological or comorbid risk factors between the TEVAR and explant groups. Risk factors identified for TEVAR failure included presence of connective tissue disorder (odds ratio [OR] 12.3, 95% confidence interval [CI] 2.3 to 25.4; p < 0.001), acute aortic dissection (OR 8.5, CI 1.7-17.6, p < 0.001), mycotic aneurysm (OR 5.8, CI 1.4-9.2, p < 0.002), and endograft undersizing (OR 2.3, CI 1.7-6.5, p > 0.003). Seventeen patients (89%) had successful thoracic endograft explant with aortic reconstruction. Among those whose thoracic endografts were explanted, early and late mortality were 15% (n = 16) and 36% (n = 12) in an 18-month average period of follow-up.
CONCLUSIONS: TEVAR failures requiring endograft explantation are associated with high mortality. Risk factors contributing to TEVAR failure were largely related to suboptimal patient selection. Patients with connective tissue disorder, acute aortic dissection, or mycotic aneurysms should be treated with caution as TEVAR does not provide durable treatment outcome.