In a prospective randomized multicentre trial, 250 patients submitted to balloon angioplasty followed by
stent implantation were randomized into control group (no local
drug delivery) or intramural delivery of
nadroparin (2 ml of 2500 anti-Xa-units/ml with a microporous
catheter). An ancillary intravascular ultrasound substudy was performed to supplement angiographic data with specific measurements of in-
stent neointimal
hyperplasia. The primary end-point was the late loss in minimal
luminal diameter on the 6 month follow-up angiogram. Secondary end-points included feasibility and safety of local
nadroparin delivery, and
major adverse cardiac events at 8 weeks and 6 months follow-up. Local delivery of
nadroparin was successful in 124 patients (99.2% success rate) and was not associated with an increase in
stent thrombosis, coronary artery dissection, side branch occlusion, distal embolization or abrupt arterial closure. At angiographic follow-up, the late loss in lumen diameter was 0.84 +/- 0.62 mm in the control group compared to 0.88 +/- 0.63 mm in the
nadroparin group (P=0.56). Angiographic restenosis rate (defined as a >50% diameter
stenosis) did not differ in the control group (20%) compared to the
nadroparin group (24%). The average area of neointimal tissue within the
stent was 2.86 +/- 0.64 mm(2) vs 2.90 +/- 0.53 mm(2) (P=0.57), control vs
nadroparin groups. There was no difference in
major adverse cardiac events at any time (88.8% vs 89.6% event free survival at 6 months, control vs
nadroparin).
CONCLUSION: