Abstract 5453: Endothelial Dysfunction Plays Important Roles on Development of Acute Coronary Syndrome and Fatal Events
Background and hypothesis: Endothelial dysfunction is thought to contribute to atherothrombogenic process, however we identify little about practical relationship between clinical evolution of acute coronary syndrome (ACS) and endothelial dysfunction. This study assessed hypothesis that endothelial dysfunction has clinical impact on development of ACS and the related prognosis.
Methods: Endothelial dysfunction was graded by ultrasonic measured reactive changes in lumen diameter of right brachial artery following transient forearm occlusion for 5 minutes (FMD; flow-mediated endothelium-dependent vasodilation) in consecutive 518 patients with stable coronary artery disease. The enrolled patients were categorized into three groups according to the values of FMD, and their cardiovascular and other clinical events were prospectively followed-up for no less than 36 months.
Results: For a mean follow-up period of 60 months with 100% follow-up, the patients with severe endothelial dysfunction (FMD<4%; Group-L, n=174), far more frequently developed ACS, compared to those in Group-M with mild endothelial dysfunction (4%≤FMD<8%, n=171) or Group-H with preserved endothelial function (FMD 8% or more, Group-H, n=173), [p<0.001, by Kaplan-Meier analysis], while the patients in group-H remained free from ACS. More than two thirds of the patients with fatal events belonged to Group-L. Cox proportional hazard model analysis showed that severe endothelial dysfunction was the most powerful predictor for future development of ACS (hazard ratio=5.77, 95%confidential interval; 2.52–13.22, p<0.001) and any fatal events (hazard ratio=5.87, 95%confidential interval; 1.26–72.25, p=0.009).
Conclusion: These results certainly suggest endothelial dysfunction plays important roles on development of ACS or any fatal events in the near future and strategies based on practical status of endothelial function are required to prevent ACS or fatal clinical events.