Evaluation of nonscarred myocardial T1 value using contrast-enhanced look-locker cardiac MRI and its relationship to cardiac function in dilated cardiomyopathy: Comparison of 1.5 and 3.0 Tesla MRI.

PURPOSE

To assess relationship between nonscarred myocardial T1 value measured using contrast-enhanced Look-Locker MRI and cardiac function in dilated cardiomyopathy (DCM) at 1.5 Tesla (T) and 3.0T MRI.

MATERIALS AND METHODS

Contrast-enhanced Look-Locker MRI was performed in 35 DCM patients. Nonscarred myocardial and blood T1 values were calculated from the signal intensity values and the delay time obtained on Look-Locker MRI. We assessed the correlation between the myocardial T1 value or myocardial T1 minus blood T1 value and cardiac function estimated using cine MRI (e.g., end-diastolic volume: EDV, left ventricular ejection fraction: LVEF) or brain natriuretic peptide (BNP).

RESULTS

With 1.5T MRI (n = 16), the myocardial T1 value correlated negatively with the EDV(r = -0.66) and end-systolic volume (ESV; r = -0.68), and positively with the LVEF (r = 0.51); the myocardial T1 minus blood T1 value correlated inversely with EDV (r = -0.70), ESV (r = -0.62), and brain natriuretic peptide (BNP; r = -0.56). With 3.0T MRI (n = 17), the myocardial T1 value correlated negatively with ESV (r = -0.44), septal thickness (r = -0.60), and BNP (r = -0.51), and positively with LVEF (r = 0.61); the myocardial T1 minus blood T1 value negatively correlated with BNP (r = -0.50) and positively with LVEF (r = 0.54).

CONCLUSION

The nonscarred myocardial T1 value measured with either 1.5T or 3.0T contrast-enhanced Look-Locker MRI is significantly related to cardiac dysfunction in DCM.