Abstract 13357: Diffuse Intimal Thickness without Lipid or Calcium Content at Branch Points is a Characteristic Feature of Coronary Artery in Patitents with Coronary Spastic Angina : Optical Coherence Tomography Analysis
Background: Endothelial nitric oxide (NO) activity is deficient at the arterial wall where shear stress is low or oscillatory. Decreased NO activity plays an important role in the development of initial arteriosclerotic lesion. Atherosclerotic plaque is often localized at the curved segment and the branching points (BPs) where shear stress is disturbed. We previously reported that CS preferentially also occurs at the distal site of BPs where shear stress is oscillatory. However, there is no report about the morphological feature of coronary artery at BPs in patients with CS.
Objective: We examined the morphological features of coronary artery around BPs in patients with CS by intravascular optical coherence tomography (OCT).
Methods: Twenty four patients with chest pain at rest and normal coronary angiogram were enrolled (59.3±10.7 yo). According to the acetylcholine provocation test, subjects were divided into 2 groups as 18 patients in whom CS was demonstrated (CS group), and 6 patients in whom CS was not demonstrated (control). OCT image acquisition was performed around CS sites after complete vasodilatation, and planimetric indices and morphological features of coronary arterial wall were assessed.
Results: Among 18 CS patients, 14 patients showed segmental diffuse CS in the distal sites of BPs, and the remaining 4 showed entire diffuse CS. The ratio of intima area/ lumen area was tended to be higher at the proximal site (P=0.139) and significantly higher at the distal site (P=0.006) of BPs in the CS group as compared with that in the control group. Furthermore, the ratio of intima area/ lumen area was significantly higher at the distal site than the proximal site of BPs in the CS group (P= 0.0215), although the ratio was similar in the control group. In the CS group, distal sites of BPs had diffuse intimal hyperplasia and no site was accompanied with lipid or calcium accumulation. This finding suggests that the intimal thickness of coronary artery in patients with CS is distinctly different to lipid laden atherosclerosis.
Conclusion: There is the diffuse intimal thickness without lipid and calcium content at the distal site of BPs in the coronary artery involved in CS.
- © 2010 by American Heart Association, Inc.