Fat in left ventricular myocardium assessed by steady-state free precession pulse sequences

Intramyocardial fat can be observed in different pathologic processes including arrhythmogenic right ventricular cardiomyopathy (ARVC) and in old myocardial infarction (OMI) In SSFP images, fat is hyperintense and surrounded by a black boundary, called "Indian Ink" artifact that is generated when fat and water coexist in the same voxel. Aim of this study was to compare the SSFP with the conventional FSE and STIR (FSE/STIR) method for the detection of LV intramyocardial fat. Fifty-four consecutive patients with OMI (>1,000 days) and 69 patients with a diagnosis of ARVC underwent magnetic resonance. LV fat was detected in 29 patients (53.7%) in SSFP images and in 28 patients (51.9%) in FSE/STIR images. At Bland- Altman plot a close agreement was found between the extent of fat measured in SSFP images and in FSE images. However, a slight systematic overestimation, was found for the fat quantification in the SSFP images. In the ARVC group, both FSE/STIR and SSFP images evidenced fat infiltration in LV myocardium in 11 patients (15.9%) without any mismatch. SSFP had 100% sensitivity and 98.8% of specificity to detect LV intramyocardial fat in ARVC and in ischemic heart disease. SSFP sequence with TR/TE = 2 is capable in identifying and quantifying the presence of fat tissue within the LV myocardium in patients with previous myocardial infarction and ARVC.