Late renal artery occlusion following endovascular repair of abdominal aortic aneurysm: a possible complication of mural thrombus formation within aortic endografts

Left Renal Artery Chronic Occlusion in the Setting of Extensive Intraprosthetic Mural Thrombus in an Abdominal Aortic Endograft

Thrombotic deposits within aortic endograft post-endovascular aortic aneurysm repair (EVAR) is a fairly well-recognized complication, yet their clinical significance remains inadequately understood. We present a rare case of extensive mural thrombus formation in an oncologic patient with a history of EVAR, emphasizing the importance of lifelong surveillance in abdominal aortic aneurysm (AAA)-EVAR patients. A 75-year-old female was admitted with refractory hypertension secondary to a medium-sized AAA, which exhibited an extensive mural thrombus, contributing to atrophic changes in the left kidney and likely chronic occlusion of the left renal artery. Factors contributing to thrombus formation generally include endograft configuration, aneurysm diameter, and patient-specific characteristics, such as a pro-thrombotic status conferred by metastatic lung cancer. This case underscores the necessity for comprehensive surveillance strategies post-EVAR. Recommendations advocate for a 30-day follow-up and lifelong annual surveillance, employing modalities such as color duplex ultrasound for detection of endoleaks and sac enlargement, with selective use of CT imaging. This case underscores the importance of continued vigilance and surveillance in patients undergoing EVAR, particularly those with complex medical histories, to mitigate potential long-term complications and optimize patient outcomes.

Significance and Risk Factors for Intraprosthetic Mural Thrombus in Abdominal Aortic Endografts: A Systematic Review and Meta-analysis

BACKGROUND

The detection of intraprosthetic thrombus (IPT) deposits is a common finding during follow-up for endovascular abdominal aneurysm repair (EVAR); however, its clinical significance is still debated. The aim of this study was to determine if IPT represents a risk factor for thromboembolic events (TEs; endograft or limb thrombosis, or distal embolization) after EVAR.

METHODS

A systematic review of English literature was undertaken until November 2017. Studies providing 2-group comparison (patients with IPT development on postoperative computed tomography angiography versus patients without IPT) with extractable outcome data (TE related to IPT and/or risk factors for IPT development) were included. Meta-analysis was performed when comparative data were given in 2 or more articles.

RESULTS

Five single-center studies (808 patients) were analyzed. IPT detection at any time during follow-up occurred in 20.8% (168/808) of patients. Extractable data for postoperative TE were available in 4 studies (613 patients): on comparative meta-analysis, IPT was not significantly associated with TE occurrence during follow-up (odds ratio 2.25, 95% confidence interval [CI] 0.50-10.1; P = 0.29). IPT is generally detected during the first year after EVAR (maximum reported median: 12 months, range: 1.2-23). Polyester graft material (odds ratio 2.34, 95% CI 1.53-3.58; P < 0.001) and aorto-uni-iliac configuration of the endograft (odds ratio 3.27, 95% CI 1.66-6.44; P = 0.001) were confirmed as risk factors for IPT formation on meta-analysis. The literature systematic review suggests that IPT formation may be also associated with long main bodies and large necks.

CONCLUSIONS

IPT detection on postoperative computed tomography angiography was not significantly associated with the occurrence of TE over time. The aorto-uni-iliac configuration and the use of polyester fabric for endografts were confirmed as risk factors for IPT development.