Endoluminal phototherapy for prevention of restenosis: preliminary results at 6-month follow-up.

OBJECTIVE: The objective of this observational study was to investigate safety and efficacy of laser phototherapy (LPh) in prevention of restenosis after percutaneous coronary intervention (PCI). BACKGROUND DATA: Laser irradiation is known to cause a limitation of the local inflammatory cascade and a stimulation of proliferation of specific cells. Based on the results of previous experiments proving the beneficial effects of laser light on the activity of vascular and inflammatory cells, we attempted to use these properties to prevent restenosis. METHODS: Laser phototherapy was performed in 41 patients after stent implantation or balloon angioplasty. Illumination power of 100 mW and energy dose equal to 9 J/cm(2) was used. Patients were monitored for major adverse cardiac events (MACE) after 30 days and 6 months. At 6 months, angiography as a control was performed to assess the influence of LPh on restenosis rate. RESULTS: Angiographic follow-up (n = 30) revealed restenosis in 9% and 25% of patients after stent implantation and balloon angioplasty, respectively. The MACE rate was 4.5% and 12.5% in stent and balloon-treated patients, respectively. CONCLUSIONS: Laser phototherapy gives very promising results in restenosis prevention, especially after stent implantation. The treatment method is safe, with a low rate of MACE in follow-up.

Estrogen-eluting, phosphorylcholine-coated stent implantation is associated with reduced neointimal formation but no delay in vascular repair in a porcine coronary model.

Estrogen can inhibit intimal proliferation and accelerate endothelial regeneration after angioplasty. This suggests that estrogen may prevent in-stent restenosis. Unlike other therapies to prevent restenosis, estrogen may also not delay endothelial regrowth, thereby avoiding the risk of late stent thrombosis. The purpose of this work was to determine the effect of a 17beta-estradiol-eluting stent on neointimal formation in a porcine model. Each artery of six pigs was randomized to either a control, low-dose, or high-dose 17beta-estradiol-eluting stent. All animals were sacrificed at 30 days for histopathological analysis. There was a 40% reduction in intimal area in the high-dose stents compared with control stents (2.54 +/- 1.0 vs. 4.13 +/- 1.1 mm(2), for high dose vs. control, respectively; P < 0.05). There was complete endothelial regeneration at 30 days and similar inflammatory response to stenting on histopathology in all the stent groups. This is the first study to show that 17beta-estradiol-eluting stents are associated with reduced neointimal formation without affecting endothelial regeneration in the pig model of in-stent restenosis. Estrogen-coated stents may have a potential benefit in the prevention and treatment of in-stent restenosis.