Application of color-coded quantitative digital subtraction angiography in predicting the outcomes of immediate type I and type III endoleaks

Abstract

Objective: Immediate type I and type III endoleaks after endovascular aneurysm repair (EVAR) could be persistent or temporary. Reintervention is necessary for persistent ones. Color-coded quantitative digital subtraction angiography (CQDSA) could provide a quantitative evaluation of the endoleak hemodynamics. We aimed to use CQDSA to quantify immediate type I and type III endoleaks after EVAR and to find a practical way to predict their outcomes.

Methods: Between January 2012 and December 2014, 485 consecutive patients with abdominal aortic aneurysms underwent EVAR at our institution. Thirty-five patients (31 men, four women) with slight immediate type I and type III endoleaks after EVAR were recruited in the prospective observational nested case-control study. After at least 6 months of follow-up, these patients were divided into two groups based on endoleak-related adverse events. Their final intraprocedure DSA images were collected and converted into a single polychromatic image for CQDSA measurements. The parameter time to peak (TTP) of the selected regions of interest in the endoleak area and a reference area at the same latitude within the stent graft were derived from the time-intensity curve. A receiver operating characteristic curve was generated to test the ability of TTP to predict endoleak-related adverse events and to identify the optimal cutoff value.

Results: Finally, two groups were identified: 12 patients with endoleak-related adverse events and 23 patients without endoleak-related adverse events. Median follow-up time for all patients was 24.0 months. Age, gender, and comorbidity were similar in these two groups. TTP was significantly lower in patients with endoleak-related adverse events (P = .002). The risk of endoleak-related adverse events was significantly higher in patients with mixed-type endoleak than in those with simple-type endoleak (P = .003). According to the receiver operating characteristic curves, TTP ≤5 seconds reached the maximal sum of sensitivity and specificity (sensitivity, 91.67%; specificity, 69.57%). Logistic regression analysis confirmed that TTP ≤5 seconds (P = .016) and mixed-type endoleak (P = .044) were associated with higher risk of endoleak-related adverse events.

Conclusions: CQDSA could help predict the outcomes of immediate type I or type III endoleaks after EVAR. TTP ≤5 seconds and mixed-type endoleak were two potential predictors of endoleak-related adverse events. This approach may offer an objective assessment of such immediate endoleaks and reference for immediate reintervention or conservative therapy.

Trial registration: ClinicalTrials.gov NCT02016131.