Peri-infarct dysfunction in post-myocardial infarction: assessment of 3-T tagged and late enhancement MRI.

摘要

OBJECTIVE: To determine LV function at different distances from myocardial infarction (MI) by using 3-T tagged MRI and late gadolinium enhancement (LGE). METHODS: Cardiac MR images were acquired from 21 patients with previous MI. The harmonic phase (HARP) method was used to calculate radial and circumferential strain (RS, CS). The two strains were synchronised by subtracting the CS from the RS at the same time, and this was defined as the efficient strain (ES). Peak strain (P-RS, P-CS, P-ES) and time to peak strain (T-RS, T-CS, T-ES) were used as estimates of contractile function. Based on the presence of LGE, myocardium was classified into infarct, border zone, adjacent and remote areas. RESULTS: P-RS and P-ES were significantly greater for remote than for adjacent and infarct areas. P-CS values were significantly greater for remote and border zone than for infarct areas. T-RS and T-ES were significantly shorter for remote and border zone than for infarct areas. T-CS was significantly shorter for border zone than for infarct areas. CONCLUSION: Contractile dysfunction demonstrated by peak strain was correlated with location at different distances from the infarct. In the border zone, contractile deformation was characterised as earlier T-RS, T-CS and T-ES and greater P-CS than in the infarct area.