3 Tesla MR cardiac applications: 6 months experience of daily clinical practice with emphasis on comparison with 1.5T Tesla for myocardial viability evaluation

Purpose: To compare 3Tesla cardiac imaging with 1.5 Tesla for myocardial viability evaluation in nearly identical experimental conditions.

Methods: 35 patients (mean age 63±11; 94.2% male) underwent both 3T and 1.5 T MR cardiac examination. Comparison between two scanner was made on the basis of the same study protocol that includes: cine b-FFE 2 and 4 chamber views multiple short-axis views (every 1cm throughout the entire LV). Perfusion is evaluated after Gadolinium injection (0.15 mmol/kg). Delayed Enhancement evaluation is performed with a segmented inversion-recovery technique. Image quality was assessed measuring Signal-to-Noise Ratio and Contrast-to-Noise Ratio in four left ventricle points in a cine b-FFE end-diastolic mid-ventricular image.

Results: We found non statistically significant differences between the two scanners (p=NS) in measuring the functional and viability parameters that follows: ejection fraction, stroke volume, cardiac output, kinesis score, perfusion score, DE score. Myocardial SNR was significantly higher with 3T MR respect to 1.5T (O,621±O,236 VS O,395±O,128 and O,656±O,120 VS O,390±0,063 measured in end-diastolic and end-systolic phase respectively) (p<0,005).

Conclusion: 3T showed high concordance with 1.5 Tesla regarding functional and viability parameters evaluation with a significant increase of SNR ratio.