Three-dimensional speckle tracking echocardiography for the evaluation of the infarct size and segmental transmural involvement in patients with acute myocardial infarction.

PURPOSE: To compare parameters between three-dimensional speckle tracking echocardiography (3DSTE) and delayed enhancement magnetic resonance imaging (DE-MRI) for estimating myocardial infarct size, peak systolic strain, and transmural involvement of infarct segments in patients with acute myocardial infarction (AMI).

METHODS: Delayed enhancement MRI was conducted to determine myocardial infarction (MI) position, size, and transmural involvement in 26 patients with AMI. 3DSTE was conducted to measure global peak systolic strain in the left ventricle and to estimate longitudinal, circumferential, and radial peak systolic strain in papillary muscle segments. Conventional echocardiography was used to calculate the wall-motion score index (WMSI) and left ventricular ejection fraction (LVEF).

RESULTS: Left ventricular strain parameters and LVEF were statistically significantly lower in patients with large-size MI than in those with small-size MI. Global longitudinal strain (GLS) and global circumferential strain (GCS) were significantly lower in patients with moderate-size MIs than in those with small-size MIs. All parameters except ejection fraction (EF) were lower in patients with large-size MI compared with those with moderate-size MI (P < 0.05). Pearson analysis revealed that left ventricular GCS, GLS, GRS, WMSI, and LVEF of AMI patients correlated with the myocardial infarct area (MIA) measured by MRI (r = 0.86, 0.81, -0.71, 0.64, and -0.66, respectively; all P-values <0.01). Transmural infarct segments exhibited significantly lower longitudinal, circumferential, and radial strains than normal segments (P < 0.05).

CONCLUSIONS: These findings indicate that 3DSTE can distinguish between MIs of different infarct sizes, and may provide an indirect means for the accurate determination of transmural involvement in infarct segments.