Diagnostic accuracy of Left atrial function and strain for differentiating between acute and chronic myocardial infarction

Abstract

Background The left atrial strain and strain rate in patients with myocardial infarction (MI) were measured using the cardiac magnetic resonance tissue tracking (CMR-TT) technique, and its usefulness in the quantitative assessment of myocardial infarction for differentiating between acute and chronic myocardial infarction was assessed. Methods Consecutive 36 AMI patients and 29 CMI patients who underwent CMR were retrospectively analyzed as well as 30 controls. By analyzing the strain from long and short left ventricular view cines from CMR-TT, the left atrial and ventricular functions were measured. Receiver operating characteristic(ROC) analysis was used to test the diagnostic accuracy of the CMR-TT strain parameters in distinguishing acute from chronic myocardial infarction. Results Participants in both AMI and CMI demonstrated decreased LA reservoir function, conduit function, and LA booster pump dysfunction as compared to the controls. The LA strain was more sensitive than the LV global strain for determining the stage of MI. Of all the LA strain parameters measured, SRa produced the best areas under the ROC curve (AUC) of 0.879 in demonstrating distinction between acute and chronic myocardial infarction. The LV strain and LA functional parameters showed the largest significant differences between chronic myocardial infarction and normal (P < 0.001, respectively), while there was no difference between AMI and normals. Conclusions CMR-TT-derived LA strain is a promising and robust tool for demonstrating impaired LA mechanics and quantifying LA dynamics, both of which have high sensitivity and specificity in the differential diagnosis of acute versus chronic myocardial infarction, and their use in clinical application is thus worth promoting.