Zarins C K, White R A, Hodgson K J, Schwarten D, Fogarty T J
Stanford University, Division of Vascular Surgery, Stanford, CA 94305-5450, USA.
J Vasc Surg. 2000 Jul;32(1):90-107. doi: 10.1067/mva.2000.108278.
The purpose of this study was to determine whether evidence of blood flow in the aneurysm sac (endoleak) is a meaningful predictor of clinical outcome after successful endovascular aneurysm repair.
We reviewed all patients in Phase II of the AneuRx Multicenter Clinical Trial with successful stent graft implantation and predischarge contrast computed tomographic (CT) imaging. The clinical outcome of patients with evidence of endoleak was compared with the outcome of patients without evidence of endoleak. The CT endoleak status before hospital discharge at 6, 12, and 24 months was determined by each clinical center as well as by an independent core laboratory. Endoleak status at 1 month was assessed with duplex scanning examination or CT at each center without confirmation by the core laboratory.
Centers reported endoleaks in 152 (38%) of 398 patients on predischarge CT, whereas the core laboratory reported endoleaks in 50% of these patients (P <.001). The center-reported endoleak rate decreased to 13% at 1 month. Follow-up extended to 2 years (mean, 10 +/- 4 months). One patient had aneurysm rupture and underwent successful open repair at 14 months. This patient had a Type I endoleak at discharge but no endoleak at 1 month or at subsequent follow-up times. There were no differences between patients with and patients without endoleak at discharge in the following outcome measures: patient survival, aneurysm rupture, surgical conversion, the need for an additional procedure for endoleak or graft patency, aneurysm enlargement more than 5 mm, the appearance of a new endoleak, or stent graft migration. Despite a higher endoleak rate identified by the core laboratory, neither the endoleak rate reported by the core laboratory nor the endoleak rate reported by the center at discharge was significantly related to subsequent outcome measures. Patients with endoleak at 1 month were more likely to undergo an additional procedure for endoleak than patients without endoleaks. Patients with Type I endoleaks at discharge and patients with endoleak at 1 month were more likely to experience aneurysm enlargement at 1 year. However, there was no difference in patient survival, aneurysm rupture rate, or primary or secondary success rate between patients with or without endoleak. Actuarial survival of all patients undergoing endovascular aneurysm repair was 96% at 1 year and was independent of endoleak status. Primary outcome success was 92% at 12 months and 88% at 18 months. Secondary outcome success was 96% at 12 months and 94% at 18 months.
The presence or absence of endoleak on CT scan before hospital discharge does not appear to predict patient survival or aneurysm rupture rate after endovascular aneurysm repair using the AneuRx stent graft. Although the identification of blood flow in the aneurysm sac after endovascular repair is a meaningful finding and may at times indicate inadequate stent graft fixation, the usefulness of endoleak as a primary indicator of procedural success or failure is unclear. Therefore, all patients who have undergone endovascular aneurysm repair should be carefully followed up regardless of endoleak status.
本研究旨在确定动脉瘤腔内血流证据（内漏）是否是血管内动脉瘤修复成功后临床结局的有意义预测指标。
我们回顾了AneuRx多中心临床试验II期所有成功植入支架移植物并在出院前进行对比计算机断层扫描（CT）成像的患者。将有内漏证据的患者的临床结局与无内漏证据的患者的结局进行比较。每个临床中心以及一个独立的核心实验室确定出院前6、12和24个月时的CT内漏状态。各中心通过双功扫描检查或CT评估1个月时的内漏状态，未得到核心实验室的确认。
各中心报告398例患者中152例（38%）在出院前CT检查时有内漏，而核心实验室报告这些患者中有50%存在内漏（P<.001）。各中心报告的1个月时内漏率降至13%。随访延长至2年（平均10±4个月）。1例患者动脉瘤破裂，于14个月时接受了成功的开放修复。该患者出院时存在I型内漏，但1个月及随后的随访时均无内漏。在以下结局指标方面，出院时有内漏和无内漏的患者之间无差异：患者生存率、动脉瘤破裂、手术转换、因内漏或移植物通畅性而需要额外手术、动脉瘤增大超过5mm、出现新的内漏或支架移植物移位。尽管核心实验室确定的内漏率较高，但核心实验室报告的内漏率和出院时各中心报告的内漏率均与随后的结局指标无显著相关性。1个月时有内漏患者比无内漏患者更有可能因内漏而接受额外手术。出院时存在I型内漏的患者和1个月时有内漏的患者在第1年更有可能出现动脉瘤增大。然而，有内漏和无内漏患者在患者生存率、动脉瘤破裂率或一级或二级成功率方面无差异。所有接受血管内动脉瘤修复患者的1年精算生存率为96%，且与内漏状态无关。12个月时一级结局成功率为92%，18个月时为88%。12个月时二级结局成功率为96%，18个月时为94%。
出院前CT扫描有无内漏似乎不能预测使用AneuRx支架移植物进行血管内动脉瘤修复后的患者生存率或动脉瘤破裂率。尽管血管内修复后动脉瘤腔内血流的发现是一个有意义的发现，有时可能表明支架移植物固定不充分，但内漏作为手术成功或失败的主要指标的有用性尚不清楚。因此，所有接受血管内动脉瘤修复的患者无论内漏状态如何均应仔细随访。
