Preoperative Magnetic Resonance Imaging (MRI) for Predicting Thromboembolic Complications during Endovascular...

Preoperative prediction of thromboembolic complications using magnetic resonance imaging (MRI) in coronary arteries and carotid arteries has been established. However, the technique has not been applied in peripheral arteries. This study aimed to assess the relationship between thromboembolic complications during endovascular treatment (EVT) for iliac artery occlusion and signal intensity on MRI.

This single-institution study included 52 iliac artery occlusions in 51 patients (mean age, 70.4 years) who underwent successful EVT between January 2010 and March 2018. MRI using an inversion recovery-prepared, steady-state free precession technique was performed preoperatively. Thromboembolic complications were defined as distal embolization and in-stent protrusion greater than 25% of the stent cross-sectional area confirmed by angiography and intravascular ultrasonography, regardless of symptoms. The highest signal intensity of iliac artery occlusion divided by the signal intensity of adjacent iliopsoas muscle (target-to-muscle ratio, TMR) was measured on MR images. Multivariate analysis was performed to clarify the predictors of thromboembolic complications during EVT.

Thromboembolic complications observed in 11 vessels (21.2%) from 11 patients comprised distal embolization (n = 4) and in-stent protrusion (n = 7). A TMR cutoff value > 2.57 had a sensitivity of 90.9%, specificity of 78.0%, positive predictive value of 52.6%, and negative predictive value of 97.0% for detecting thromboembolic complications during EVT. In the multivariate analysis, TMR >2.57 was the only independent factor associated with thromboembolic complications (odds ratio, 30.10; 95% confidence interval, 3.26-278.00; P = 0.003).

The presence of higher signal intensity in iliac artery occlusion on MRI is useful for predicting thromboembolic complications during EVT.