Acute coronary syndrome: evaluation of detection capability using non-electrocardiogram-gated parenchymal phase CT...

To evaluate the capability to detect acute coronary syndrome (ACS) by using non-electrocardiogram-gated parenchymal phase CT imaging.

Of 962 consecutive patients who underwent emergent coronary angiography for suspected ACS, 32 with ACS who underwent CT ≤24 h before angiography and 15 without ACS who underwent CT ≤24 h before or after angiography were included. Parenchymal phase was acquired at 100-s scan delay. The presence of a myocardial perfusion defect (MPD) on the left ventricle (a decrease of >20 HU) and its capability to detect ACS were evaluated. Results were compared with laboratory findings.

MPD was detected in 29 of 32 ACSs. The sensitivity, specificity, and positive and negative predictive values were 91 % (29/32), 93 % (14/15), 97 % (29/30), and 82 % (14/17), respectively. The sensitivities of ST- and non-ST-elevation ACSs were 89 % (16/18) and 93 % (13/14), respectively, without significant difference (P > 0.99). Of the CT-detectable ACS, non-ST-elevation on the electrocardiogram and a normal creatine kinase-myocardial band were observed in 41 % (12/29) and 24 % (7/29), respectively.

ACS is highly detectable even using conventional parenchymal phase CT imaging. Therefore, even when CT is non-gating, radiologists should carefully evaluate the heart to avoid overlooking ACS.