Left ventricular function, volumes, and mass in MRI studies using SFPP versus FLASH sequences in an animal model

OBJECTIVE
To compare the accuracy of two cine-gradient-echo sequences to quantify left ventricular function, volumes, and mass in an animal model.

MATERIAL AND METHODS
We studied ten Gottingen miniature pigs (seven male, three female; mean weight 49.8+/-10.65kg; range: 35-65kg) with a 1.5 Tesla MRI scanner using free-breathing SSFP and FLASH sequences. We used 8-mm short-axis images to estimate left ventricular ejection fraction (EF), volumes (end-diastolic (EDV), end-systolic (ESV), and stroke volume (SV)), mass, and signal-to-noise ratio (SNR) on SSFP and FLASH sequences. We analyzed the correlation and concordance of the two sequences for each variable.

RESULTS
Using the SSFP sequence, the mean estimated EF was 77.35+/-3.13%; mean EDV 61.55+/-8.64ml; mean ESV 13.83+/-1.92ml; mean SV 47.72+/-7.78ml; and mean myocardial mass 75.87+/-11.44g. Using the FLASH sequence, the mean EF was 81.87+/-2.22%; mean EDV 55.4+/-8.08ml; mean ESV 10.03+/-1.87ml; mean SV 45.38+/-6.83ml; and mean myocardial mass 87.74+/-15.21g. The correlation between SSFP and FLASH to quantify EDV, SV, and myocardial mass was excellent (r>0.8) and moderate (r>0.4) for quantifying ESV and EF. The SNR in the SSFP sequence was significantly higher than in the FLASH sequence (mean difference 120.94+/-42.94).

CONCLUSIONS
In the SSFP sequence, ventricular volumes are slightly higher and ventricular mass is slightly lower than in the FLASH sequence, probably because of the higher SNR on SSFP sequences.

CITATION Radiologia. 2009 Mar-Apr;51(2):156-62