Effects of stent design and serum cholesterol level on the restenosis rate in atherosclerotic rabbits

Abstract We investigated the effect of serum cholesterol level and stent design on the restenosis rate within the stent after balloon angioplasty and stent implantation using atherosclerotic rabbits. Two types of nicket/titanium stents with gaps (open stent) and without gaps (closed stent) between the wire coils were implanted into the aorta of the rabbits 10 weeks after atherosclerosis had been induced using a standard high cholesterol diet and balloon abrasion. Each rabbit had an open stent and a closed stent implanted into the infrarenal abdominal aorta. Between these two stents a control segment of the aorta was treated with angioplasty alone. The animals were divided into two groups according to the diet protocol as follows: in group I ( n = 9) a high cholesterol diet was stopped after stent implantation; in group II ( n = 10) a high cholesterol diet was maintained after stent implantation. Digital subtraction angiograms were obtained every 4 weeks for up to 24 weeks and the narrowest diameter of the arterial segments within each stent and in the segment between stents was measured. The diameter narrowing within the closed stent was greater in the high cholesterol group compared with the low cholesterol group: 12 weeks (2.57 ± 0.09 mm in group I vs 2.14 ± 0.15 mm in group II, mean ± S.E., p p p p