Coronary vasospastic angina: assessment by multidetector CT coronary angiography

Abstract

Objective: We aimed to describe the imaging findings of multidetector CT coronary angiography (MDCTA) in cases of vasospastic angina (VA) and to determine the accuracy of MDCTA in the identification of VA as compared with invasive coronary angiography with an ergonovine provocation test (CAG with an EG test).

Materials and methods: Fifty-three patients with clinically suspected VA were enrolled in this study. Two radiologists analyzed the stenosis degree, presence or absence of plaque, plaque composition, and a remodeling index of the related-segment in CAG with an EG test, which were used as a gold standard. We evaluated the diagnostic performances of MDCTA by comparing the MDCTA findings with those of CAG with an EG test.

Results: Among the 25 patients with positive CAG with an EG test, all 12 patients with significant stenosis showed no definite plaque with the negative arterial remodeling. Of the six patients with insignificant stenosis, three (50%) had non-calcified plaque (NCP), two (33%) had mixed plaque, and one (17%) had calcified plaque. When the criteria for significant stenosis with negative remodeling but no definite evidence of plaque as a characteristic finding of MDCTA were used, results showed sensitivities, specificities, positive predictive values (PPV), and negative predictive values (NPV) of 48%, 100%, 100%, and 68%, respectively.

Conclusion: Significant stenosis with negative remodeling, but no definite evidence of plaque, is the characteristic finding on MDCTA of VA. Cardiac MDCTA shows good diagnostic performance with high specificity and PPV as compared with CAG with an EG test.

Keywords: Coronary artery; Multidetector CT; Spasm.

Figures

Fig. 1

41-year-old man with acute chest pain. Significant discrete stenosis is noted in middle segment of left anterior descending artery (arrows) on volume rendering image (A), short-axis multiplanar image (B), and curved multiplanar multidetector CT coronary angiography images (C). However, there is no discernable atheroma in related segment, suggesting coronary spasm (B). Mild luminal irregularity is shown at corresponding segment of left anterior descending artery (arrow) on invasive coronary angiography (D). However, provoked tight stenosis occurs at same site (arrow) on invasive coronary angiography after intracoronary administration of ergonovine (E).

Fig. 2

55-year-old woman with acute chest pain. Curved multiplanar multidetector CT coronary angiography image (A) demonstrating significant discrete stenosis with internal low attenuated area at middle segment of right coronary artery (arrow). Insignificant stenosis is shown at corresponding segment (arrow) on invasive coronary angiography (B). Provoked severe stenosis is revealed at same site (arrow) on invasive coronary angiography after intracoronary administration of ergonovine (C).