R. Hoffmann et al., The impact of high pressure vs low pressure stent implantation on intimal hyperplasia and follow-up lumen dimensions - Results of a randomized trial, EUR HEART J, 22(21), 2001, pp. 2015-2024
Aims Histology and retrospective clinical studies have indicated that the a
mount of neointimal hyperplasia is dependent on the arterial injury induced
during stent implantation. This study analysed, prospectively, the impact
of high vs low pressure stent implantation techniques using a second genera
tion stent on intimal hyperplasia and follow-up lumen dimensions.
Methods and Results Post-intervention and follow-up (mean[+/- SD] 5.5 +/- 1
.3 months) angiographic and intravascular ultrasound studies were performed
on 120 MultiLink HP stents randomized to implantation at either low (8-10
atm) or high (16-20 atm) pressure. Intravascular ultrasound measurements of
the external elastic membrane, stent, and lumen cross-sectional area were
performed at 1 mm axial increments. Peri-stent plaque+media cross-sectional
area (external elastic membrane-stent cross-sectional area, intimal hyperp
lasia cross-sectional area (stent-lumen cross-sectional area at follow-up),
intimal hyperplasia thickness and peri-stent tissue growth cross-sectional
area (Delta persistent plaque+media cross-sectional area) were calculated.
Intravascular ultrasound demonstrated a larger minimal lumen cross-section
al area postintervention in the high pressure group (7.3 +/- 2.0 vs 6.2 +/-
1.8 mm(2), P <0.001, high vs low pressure a cup, group respectively). At f
ollow-up, the mean intimal hyperplasia cross-sectional area (1.7 +/- 0.9 vs
1.5 +/- 0.8 mm(2), P=0.708), the mean intimal hyperplasia thickness (0.16
+/- 0.12 vs 0.16 +/- 0.12 mm, P=0.818) and peri-stent tissue proliferation
cross-sectional area were not greater in the high pressure group. Thus, the
minimal lumen cross-sectional area at follow-up continued to be greater (5
.5 +/-2.0 vs 4.7 +/-1.7 mm(2), P=0.038) in the high pressure group.
Conclusions High pressure stent implantation results in greater stent expan
sion even with the less rigid second generation Multi-Link stent. Larger lu
men dimensions persist at follow-up, while intimal hyperplasia is not signi
ficantly greater after high pressure implantation compared to the low press
ure technique. (C) 2001 The European Society of Cardiology.