Dye-staining angiography detects atherosclerosis early

Dye-staining angiography combining Silius Red (SR) and Fast Green (FG) dyes to visualize collagen subtypes can help detect atherosclerosis early, a recent study has found.

Fifty-one coronary arteries were excised from 20 autopsies (mean age 60±2.6 years, 14 men) and were subjected to angioscopy to classify coronary plaques and normal segments. Collagen staining was performed using SR and FG.

After staining, the researchers found that combination of SR and FG could differentiate between the different collagen subtypes: collagen III was stained emerald-green, I was red, and IV and V were coloured pink.

Moreover, the colour distribution changed across different angioscopic and histologic characteristics. For instance, normal coronary segments with intimal thickness ≤200 µm were predominantly green, while similar segments with >200-µm thick intima showed a mixture of red and green.

The green colour, in particular, was common in segments with intimal thickness >200 µm and was observed in both normal segments and segments with white plaques. Those with yellow plaques were either remained unstained or were coloured pink depending on whether they had a necrotic core or not, respectively.

The ability to easily discriminate between collagen subtypes in coronary arteries could improve the diagnosis of atherosclerosis, the researchers said.

“Because collagen I, the major subtype in the normal vessel wall, stained red and collagen III which appears in the early stage of atherosclerosis stained emerald-green, the beginning and early stage of atherosclerosis in the superficial layer of the coronary artery could be detected by angioscopy,” they added.