PB0015 - Rose bengal- mediated catheter- based polarized green laser photodynamic therapy after stenotic artery thermal angioplasty for inhibition of restenosis

Background: Atherosclerosis result in plaque formation and plaque rupture leads to arterial thromboembolism. The laser atherectomy methods that are currently in use, cause to inflammation and subsequent restenosis.

Aims: The aim of this study was to evaluate the effect of rose bengal- mediated catheter- based photodynamic therapy on inflammation and intimal hyperplasia reduction after laser angioplasty of the animal occluded femoral artery, wherein diagnostic ultrasound is adjuncted with angioplasty and combination therapy system, with a goal of increased safety.

Methods: Briefly, New Zealand white rabbits were submitted to femoral artery advanced atherosclerotic occlusion by primary perivascular severe cold injury followed by a 2% cholesterol- rich diet for fourteen weeks. Histopathology results showed the formation of stable advanced atherosclerosis with lipid and neovessel- rich plaque, resulted in occlusion in all of the rabbits’ arteries. Then treatment group underwent B- mode ultrasound- guided argon laser (488 nm) angioplasty followed by rose bengal- mediated catheter- based polarized green laser (λ= 532 nm, E/A= 150 J/cm2) photodynamic therapy.

Results: Results from ultrasonography and histopathology showed a significant reduction in the mean value for immune cells and smooth hyperplastic smooth muscle cells density after angioplasty in the treatment group compared with the other groups (p < 0.05).

Conclusion(s): Cytotoxic and anti- inflammatory effect of rose bengal- induced by green laser, can cause to reduce the density of immune cells, foam cells and smooth muscle hyperplasia cells in the intimal layer. These findings provide the basis for developing of combined photodynamic therapy for a successful clinical application in the treatment of neointimal hyperplasia after laser angioplasty.