Abstract 12554: Endothelial Dysfunction but not Vascular Smooth Muscle Dysfunction Plays Important Roles on Development of Acute Coronary Syndromes and Fatal Cardiovascular Events
Background: Arterial dysfunction is thought to contribute to atherothrombogenic process, however we identify little about practical relationship between clinical evolution of acute coronary syndromes and arterial dysfunction. This study investigated whether arterial dysfunction has clinical impact on development of acute coronary syndromes.
Methods: Arterial 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 vasodilatation), and dilation of brachial artery after sublingual administration of nitroglycerin (TNG) in consecutive 518 patients with stable coronary artery disease. The enrolled patients were categorized into three groups according to the values of FMD or TNG, and their cardiovascular and other 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%, n=174) and the patients with severe vascular smooth muscle dysfunction (TNG<11%, n=145) more frequently developed acute coronary syndromes and fatal cardiovascular events. Cox proportional hazard model analysis showed that severe endothelial dysfunction was the most powerful predictor for future development of acute coronary syndromes (hazard ratio=5.77, 95%confidential interval; 2.52-13.22, p<0.001) and fatal cardiovascular events (hazard ratio=10.34, 95%confidential interval; 1.26-72.25, p=0.022). However severe vascular smooth muscle dysfunction was not a significant predictor for future development of acute coronary syndromes (hazard ratio=1.82, 95%confidential interval; 0.84-3.93, p=0.124) or fatal cardiovascular events (hazard ratio=2.25, 95%confidential interval; 0.65-5.24, p=0.152).
Conclusion: These results suggest endothelial dysfunction but not vascular smooth muscle cell dysfunction plays important roles on development of acute coronary syndromes and fatal cardiovascular events in the near future and strategies based on practical status of endothelial function are required to prevent acute coronary syndromes and fatal cardiovascular events.
- © 2011 by American Heart Association, Inc.