Retrospective assessment of at-risk myocardium in reperfused acute myocardial infarction patients using contrast-enhanced balanced steady-state free-precession cardiovascular magnetic resonance at 3T with SPECT validation.

ABSTRACT

BACKGROUND: Contrast-enhanced (CE) steady-state free precession (SSFP) CMR at 1.5T has been shown to be a valuable alternative to T2-based methods for the detection and quantifications of area-at-risk (AAR) in acute myocardial infarction (AMI) patients. However, CE-SSFP's capacity for assessment of AAR at 3T has not been investigated. We examined the clinical utility of CE-SSFP and T2-STIR for the retrospective assessment of AAR at 3T with single-photon-emission-computed tomography (SPECT) validation. MATERIALS AND METHODS: A total of 60 AMI patients (ST-elevation AMI, n = 44;  non-ST-elevation AMI, n = 16) were recruited into the CMR study between 3 and 7 days post revascularization. All patients underwent T2-STIR, CE-bSSFP and late-gadolinium-enhancement CMR. For validation, SPECT images were acquired in a subgroup of patients (n = 30). RESULTS: In 53 of 60 patients (88 %), T2-STIR was of diagnostic quality compared with 54 of 60 (90 %) with CE-SSFP. In a head-to-head per-slice comparison (n = 365), there was no difference in AAR quantified using T2-STIR and CE-SSFP (R2 = 0.92, p < 0.001; bias-0.4 ± 0.8 cm2, p = 0.46). On a per-patient basis, there was good agreement between CE-SSFP (n = 29) and SPECT (R2 = 0.86, p < 0.001; bias - 1.3 ± 7.8 %LV, p = 0.39) for AAR determination. T2-STIR also showed good agreement with SPECT for AAR measurement (R2 = 0.81, p < 0.001, bias 0.5 ± 11.1 %LV, p = 0.81). There was also a strong agreement between CE-SSFP and T2-STIR with respect to the assessment of AAR on per-patient analysis (R2 = 0.84, p < 0.001, bias - 2.1 ± 10.1 %LV, p = 0.31). CONCLUSIONS: At 3T, both CE-SSFP and T2-STIR can retrospectively quantify the at-risk myocardium with high accuracy.