Non-Contrast UTE MRI Guided Staging Predicts In-Vivo Lower Extremity Endovascular Procedural Complexity.

Abstract

Our understanding of plaque morphology and its relationship with procedural complexity and immediate technical failure (ITF) in percutaneous vascular intervention (PVI) is poorly understood, particularly in tibial disease due to significant limitations of CTA, DSA and DUS imaging. Ultrashort echo time (UTE) MRI is a non-contrast 3T MRI technique that can identify and differentiate plaque morphology and characteristics. The aim of this study was to create a UTE MRI-defined staging system to support clinicians evaluate endovascular procedural complexity. Patients scheduled for PVI underwent pre-operative UTE MRI. Lesions were graded based on MRI-defined anatomical characteristics and plaque morphology on a four-scale staging system, where stage A was least severe and stage D most severe. The primary outcome was the association of UTE Stage with ITF and was evaluated using logistic regression. Secondary outcomes included associations between UTE Stage and number of wire/catheter escalations required during the procedure, and UTE Stage and number of treatment devices used. TASC scoring was also evaluated and investigated for any influence on ITF. 47 patients with 90 arterial lesions were included. Stage D and stage C UTE MRI- defined disease strongly influenced ITF (Odds ratio 114.3, 95% CF 10.4-1257.5, p<0.001 and OR 21.0 95% CF 2.33-189.3, p=0.007 respectively). Logistic regression identified Stage D disease was 99 times more likely to require catheters/wire escalations for crossing (OR 0.01, p=0.004, 95% CF 0.00-0.24). UTE MRI stage did not influence number of treatment devices used (Chi 2.53, p=0.47). Logistic regression showed that TASC score had no influence on ITF (Chi 2.13, p=0.55). UTE-MRI defined staging is strongly associated with ITF, crossing time and need for crossing device escalation whereas TASC staging had no influence on ITF. This study supports the notion that an understanding of plaque morphology and plaque characteristics is pivotal to procedural planning.