Coronary artery calcification as a novel predictive marker of unstable coronary lesion in survivors of out-of-hospital cardiac arrest without ST-segment elevation.

Aim: Acute myocardial infarction (AMI) is the leading cause of out-of-hospital cardiac arrest (OHCA). A highly predictive marker is needed to identify AMI in survivors of OHCA without ST-segment elevation because the appropriate indication for emergency coronary artery angiography in patients without ST-segment segment elevation has not been determined. Accordingly, the aim of this study was to elucidate the clinical significance of coronary artery calcification in identifying survivors of OHCA without ST-segment elevation who could benefit from emergency coronary artery angiography.

Methods: Survivors of OHCA without ST-segment elevation with no obvious extra-cardiac cause who underwent emergency computed tomography and coronary artery angiography were enrolled. Unstable coronary lesion was diagnosed using coronary artery angiography, and presence of coronary artery calcification and coronary artery calcium score were evaluated by non-contrast, non-electrocardiography gated computed tomography.

Results: Thirty of 100 consecutive survivors of OHCA were diagnosed to have unstable coronary lesion. Sensitivity and specificity of coronary artery calcification in identifying unstable coronary lesion were 87% and 60%, respectively. Multivariate logistic regression analysis revealed that coronary artery calcification was an independent predictor of unstable coronary lesion (odds ratio: 7.28, 95% confidence interval: 2.00-26.56, p < 0.001).

Conclusion: Evaluation of coronary artery calcification by computed tomography is useful in identifying patients with unstable coronary lesion who could benefit from emergency coronary artery angiography among survivors of OHCA without ST-segment elevation on post-resuscitation electrocardiography.