Abstract
INTRODUCTION: Acute stent thrombosis and in-stent restenosis are serious complications of percutaneous coronary intervention (PCI) and may be associated with vascular or platelet abnormalities. We aimed to assess endothelium-dependent vasomotion, endogenous fibrinolysis and platelet function in patients with acute stent thrombosis or in-stent restenosis.
MATERIALS AND METHODS: Thirty-six subjects were enrolled into four groups: acute stent thrombosis, in-stent restenosis, uncomplicated PCI with stent implantation and healthy matched controls. Forearm blood flow was measured using bilateral venous occlusion plethysmography during intra-brachial acetylcholine, substance P and sodium nitroprusside infusion. Venous blood samples were withdrawn for estimation of plasma fibrinolytic variables and platelet aggregometry.
RESULTS: Acetylcholine, substance P and sodium nitroprusside caused dose-dependent increases in blood flow (P < 0.001) and substance P caused a dose-dependent increase in tissue-type plasminogen activator (t-PA) release (P < 0.001) in all groups. Thrombin, collagen, adenosine diphosphate (ADP) and the thromboxane A2 analogue, U46619, caused dose-dependent platelet aggregation (P < 0.001) in all groups. There were no significant between group differences in these responses except that, in keeping with aspirin therapy, collagen-induced platelet aggregation was impaired in patient groups compared with healthy controls (P < 0.01). Post-hoc analysis demonstrated a significant impairment of acute t-PA release in current smokers compared to non-smokers (P < 0.05).
CONCLUSIONS: Despite previous reports suggesting impaired vascular function, endothelium-dependent vasomotion, endogenous fibrinolysis and platelet aggregation do not appear to play a major role in the pathogenesis of acute stent thrombosis or in-stent restenosis.
Original language | English |
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Pages (from-to) | 343-9 |
Number of pages | 7 |
Journal | Thrombosis Research: Vascular Obstruction, Hemorrhage and Hemostasis |
Volume | 111 |
Issue number | 6 |
Publication status | Published - 2003 |
Keywords
- Acetylcholine
- Aged
- Case-Control Studies
- Coronary Restenosis
- Coronary Thrombosis
- Endothelium, Vascular
- Female
- Fibrinolysis
- Humans
- Male
- Middle Aged
- Nitroprusside
- Platelet Aggregation
- Regional Blood Flow
- Stents
- Substance P