Background: Cardiac arrest (CA) is the most severe complication of acute myocardial infarction (AMI). Besides the location and severity of coronary occlusion, different factors may have significant role in the pathogenesis of AMI-related cardiac arrest (CA), but their contribution is still under investigation. The aim of the study was to investigate the cardiac magnetic resonance (CMR) features of myocardial injury associated with a higher risk of CA accompanying an AMI.
Methods: In total, 918 myocardial segments from 54 post-AMI patients undergoing CMR imaging with delayed gadolinium enhancement were enrolled in the study, of which 18.54% presented CA during the acute phase of AMI. In all patients, infarct mass, the proportion of high transmurality extent, and scar mass at different myocardial segments were calculated using QMap software (Medis BV).
Results: Compared to patients without CA, those with CA had a significantly higher infarct size (p = 0.03) and a higher degree of transmurality (29.28% vs. 14.1%, p = 0.01). The risk of CA during the acute phase was significantly higher in patients in whom the location of myocardial injury was at the level of latero-apical, antero-lateral, and basal anterior segments. Group 1 presented a larger infarct size at the level of the latero-apical (33.9 ± 30.6 g vs. 13.6 ± 17.3 g, p = 0.02), anterolateral (26.5 ± 29.0 g vs. 8.9 ± 12.8 g, p = 0.02), and anterobasal segment (20.1 ± 21.5 g vs. 7.8 ± 14.7 g, p = 0.02).
Conclusions: CMR imaging identified infarct mass, high transmurality degree, and large myocardial injury as features associated with an increased risk of CA in the acute phase of AMI, especially at the level of anterolateral segments.
