ObjectiveRecent randomized controlled trials have demonstrated a notable prevalence of immediate technical failures (ITFs) in percutaneous vascular interventions (PVIs) for complex arterial lesions associated with chronic limb-threatening ischemia (CLTI). Current imaging modalities present inherent limitations in identifying these lesions, making it challenging to determine the most suitable candidates for PVI. We present a novel preprocedural magnetic resonance imaging (MRI) histology protocol for identifying lesions that might present a higher rate of immediate and mid-term PVI failure. Methods22 patients (13 females, average age 65.8±9.72 years) scheduled for PVI were prospectively enrolled and underwent 3T MRI using ultrashort echo time and ‘Steady-State Free Precession’ contrasts to characterize target lesions prior to PVI. Lesions were scored as ‘hard’ if >50% of the lumen was occluded by hard components (calcium/dense collagen) on MRI in the hardest cross-section. Two readers evaluated MRI datasets. TASC/GLASS/WIFi scoring was performed based on intraprocedural angiograms and chart review. The relationship between MRI scoring, TASC/GLASS scoring and procedural outcomes was investigated using univariate analysis. Mid-term follow-up (revascularization and amputation rate) was recorded at 3 months and 6 months, post-intervention. ResultsOur cohort of 22 patients yielded 40 target lesions. 5 lesions were excluded (2 non-diagnostic image quality, 3 PVIs were ultimately diagnostic only). 6 lesions (17%) were scored as ‘hard’. MRI-scored ‘hard’ lesions had higher proportion of ITF (‘hard’ vs ‘soft’ 83% (n/N=5/6) vs. 3% (n/N=1/29), p<.001). ‘Hard’ versus ‘soft’ MRI scoring was the only factor significantly associated with immediate PVI technical success (p < .001), as opposed to TASC/GLASS scoring. Both at 3 months and 6 months after PVI, the re-intervention rate was significantly higher among those lesions which were scored ‘hard’ on MRI (3-month: hard: 80% vs. soft: 16%, p =.011 6-month: hard: 80%, soft: 27%, p=.047). ConclusionsMRI histology could be a valuable tool for optimizing PVI patient selection and treatment strategies.