Abstract 11105: In vivo Assessment of Focal Coronary Artery Spasm by Multislice Computed Tomography
Background: Coronary artery spasm has been shown to play an important role in the pathogenesis of not only variant angina but also many types of ischemic heart disease. Previous studies have shown that atherosclerosis is present at the site of focal coronary spasm. Noninvasive detection of atherosclerotic plaque related to coronary artery spasm by multislice computed tomography (MSCT) would be useful in clinical setting. However, data of MSCT about coronary spasm are scarce. The aim of this study was to investigate the morphological features of vascular wall at the site of focal coronary artery spasm and diagnostic possibility of coronary spasm by MSCT.
Methods and Results: From January 2006 to December 2009, 183 patients with clinically suspected coronary spastic angina who had no angiographic significant obstructive coronary disease were analyzed by MSCT and invasive angiography with ergonovine provocative test. Focal coronary spasm was defined as localized vessel narrowing associated with ischemic electrocardiographic change and chest pain. A total of 264 plaques were detected by MSCT and divided into spasm group (n=38) or non-spasm group (n=226) based on the results of provocative test. Attenuation of plaque (low (<50 Hounsfields Units(HU), intermediate(50–150HU) or high(150HU<)), patterns of vascular remodeling (positive, intermediate or negative), and degree of calcification (non-calcified, spotty (size in=3mm) or large (size in>3mm)) were evaluated in each plaque. Intermediate attenuation plaque was more frequently observed in spasm group than non-spasm group (86% vs 12%, p<0.01). Negative remodeling was more frequently identified in spasm group (58% vs 11%, p<0.01). Non-calcified plaque was more common in spasm group (83% vs 21%, p<0.01). Presence of all 3 findings of intermediate attenuation, negative remodeling and non-calcified provided the sensitivity of 55%, specificity of 98%, positive predictive value of 84% and negative predictive value of 92% for detecting the plaque related to spasm. At the sites of plaque-free and plaque with large calcification, no coronary spasm was provoked.
Conclusion: MSCT can be a useful modality to diagnose focal coronary artery spasm.
- © 2010 by American Heart Association, Inc.