thesis
Intracoronary Brachytherapy: a New Technique to Prevent Restenosis After Percutaneous Coronary Interventions
- Publication date
- 10 May 2000
- Publisher
- Percutaneous trans luminal coronary angioplasty (PTCA) is an accepted treatment for
coronary artery disease. However, angiographical restenosis is reported in 40-60% of patients
after a successful PTCA. Mechanisms involved in the restenosis process are elastic recoil of
the artery, local thrombus formation, vascular remodeling with shrinkage of the vessel and an
overact healing process with neointimal hyperplasia.
Neointimal hyperplasia develops by
migration and proliferation of smooth muscle cells and myofibroblasts after balloon induced
trauma of the arterial wall and by deposition of an extracellular matrix by the smooth muscle
cells. The introduction of the stent in the arsenal of the interventional cardiologist has reduced
the restenosis rate to 15-20%, by preventing elastic recoil and negative remodeling.
However, the occurrence of restenosis after stent implantation remains unresolved, especially in
small vessels and long lesions, where it may exceed 30% of the cases. It is primary caused by
neointimal hyperplasia, which occurs due to trauma of the arterial wall by