Abstract 313: Noninvasive Detection and Evaluation of Coronary Plaque at the Site of Coronary Spasm in Patients With Coronary Spastic Angina Using 64-Slice Multislice Computed Tomography
Background: The characteristics of coronary plaque at the site of a coronary spasm have not yet been elucidated by 64-slice multislice computed tomography (MSCT).
Methods and Results: Between June 2005 and December 2008, 64-slice MSCT was performed in 72 patients with clinically suspected of having coronary spastic angina (CSA) before undergoing invasive angiography. No significant organic coronary artery stenosis (≥ 75%) was observed in the 3 major coronary arteries angiographically in any of the patients. Forty patients were diagnosed as CSA by a provocation test for coronary spasm with intracoronary injection of ergonovine maleate. Thirty of the 40 CSA patients had coronary spasms in the left anterior descending coronary artery (LAD). Three patients with CSA and 2 patients without CSA were excluded in the present study because of poor images in MSCT. Twenty-seven patients with CSA (CSA-group: 24 males; age 64±9 years) and 30 patients who were not diagnosed as CSA (Control-group: 13 males; age 65±11 years) were included in the present study. In the proximal LAD, coronary plaques at the site of coronary spasm in the CSA-group and those of the Control-group were evaluated and compared between the two groups by MSCT. The ratio of males was significantly higher (24/27 vs. 13/30, p < 0.01) in the CSA-group than in the Controls. Coronary plaque was detected in 26 patients in the CSA-group and 24 subjects in the Controls. The CSA-group had a significantly larger plaque area (12.89±5.94 vs. 7.70±3.36 mm2, p < 0.001), a higher % area stenosis (64.92±17.41 vs. 41.59±17.24%, p < 0.001), a larger remodeling index (1.41±0.35 vs. 1.21±0.15, p < 0.05), a smaller lumen area (6.38±3.50 vs. 11.22±5.13 mm2, p < 0.01) and a lower minimal MSCT plaque density (−2.23±16.07 vs. 12.54±25.15 HU, p < 0.05) in comparison to the Controls. The total vessel area (19.26±6.16 vs. 18.92±5.29 mm2, NS), the reference vessel area (14.81±5.18 vs. 15.88±4.72 mm2, NS) and the degree of calcified plaque were also comparable between the two groups.
Conclusion: 64-slice MSCT shows that decompensated positive remodeling plaque is associated with coronary spasm.