Fibro-fatty volume of culprit lesions in virtual histology ^™ intravascular ultrasound is associated with the amount of debris during carotid artery stenting

Objectives: This study aimed to evaluate the relationship between the amount of aspirated debris during distal balloon-protected carotid artery stenting (CAS) and the pre-intervention plaque composition, as assessed by Virtual Histology^™ (VH) intravascular ultrasound (IVUS). Methods: The study subjects were 25 consecutive patients (mean age, 73.0 ± 5.2 years; 20 males and 5 females) who underwent CAS under distal balloon protection. The average rate of carotid stenosis was 74.6 ± 12.9% by North American Symptomatic Carotid Endarterectomy Trial criteria. We assessed culprit plaque components by VH-IVUS before CAS. Aspirated debris was filtered, stained with HE and mounted onto glass slides. The quantity of debris was evaluated by measuring its surface area. We evaluated the relationship between the quantity of aspirated debris and VH-IVUS measurements before CAS. Results: The amount of debris during CAS was positively correlated with the total plaque volume in grayscale IVUS (Rs = 0.480, p = 0.015) and fibro-fatty volumes over the entire lesion length in VH-IVUS (Rs = 0.561, p = 0.001). Conclusions: Culprit lesions with large plaque volumes, especially larger fibro-fatty volumes, as imaged by VH-IVUS, are associated with large amounts of debris during balloon-protected CAS.