Abstract
It has been the great problems that the coronary intervention (PCI) using the balloon had a low initial success rate and a high recurrence rate. An excimer laser, one of the Debulking devices, is considered to solve those problems of balloon angioplasty because of excellent vaporizing effect.
Although we have new sophisticated devices now, there are still some difficult lesions treated by coronary intervention, thrombus abundant lesions, re-stenotic lesions, severely calcified lesions and totally occluded lesions. There are a large possibility of dispersing debris of the thrombus and atheroma, existing in a culprit lesion of acute myocardial infarction or in a degenerative vein graft, into the distal coronary bed during procedures of angioplasty. Moreover, although we have a drug eluting stent proven to have a remarkable low rate of restenosis after implantation, the established treatment for in-stent re-stensis does not exist.
We tested the clinical feasibility of the laser by focusing on acute myocardial infarction and in-stent re-stenosis. In terms of acute myocardial infarction, we performed LAMI trail as joint research of three institutions in the Hanshin area. In the result, procedure success was 96.9% and a final TIMI3 acquisition rate 97.8%. Those results were as good as CARMEL trial. We had the excellent final %MLD (5.0%), although some adjunctive therapy such as stenting was needed because of residual stentosis of 56.5% immediate after laser. Moreover, in 28 patients with in-stent re-stenosis, we compared the laser with the drug elution stent, a most effective device for preventing re-stenosis, in clinical usefulness and cost of treatment. In seven patients treated laser and 21 patients implanted DES, there was no significant difference of MACE (death, myocardial infarction, target lesion revascularization rate) between two groups. Because the cost of laser treatment was a lower, laser is expected as a new treatment of in-stent re-stenosis.
