ST-Segment Resolution as a Marker for Myocardial Scar in ST-Segment Elevation Myocardial Infarction

Objective: To investigate the relationship between ST-segment resolution (STR) and myocardial scar thickness after percutaneous coronary intervention (PCI) in patients with ST-segment elevation myocardial infarction (STEMI). Methods: Forty-two STEMI patients with single-branch coronary artery stenosis or occlusion were enrolled. ST-segment elevations were measured at emergency admission and at 24 h after PCI. Late gadolinium-enhanced cardiac magnetic resonance imaging (CMR-LGE) was performed 7 days after PCI to evaluate myocardial scars. Statistical analyses were performed to assess the utility of STR to predict the development of transmural (>75%) or non-transmural (<75%) myocardial scars. Results: The sensitivity and specificity of STR for predicting transmural scars were 96% and 88%, respectively, at an STR cut-off value of 40.15%. The area under the curve was 0.92. Multivariate logistic proportional hazards regression analysis disclosed that patients with STR<40.15% had a 112.95-fold higher probability of developing transmural scars compared with patients with STR≥40.15%. STR percentage was negatively correlated with myocardial scar thickness (β=-0.838, P <0.001) and size (β=-0.714, P <0.001). Conclusion: STR<40.15% at 24 h after PCI may provide meaningful diagnostic nformation regarding the extent of myocardial scarification in STEMI patients.