Rapidly reversible myocardial edema in patients with acromegaly: assessment with ultrafast T2 mapping in a single-breath-hold MRI sequence.

OBJECTIVE

The purpose of this study was to use a single-breath-hold T2-mapping MRI sequence to evaluate the reversibility of myocardial edema in patients treated for acromegaly.

SUBJECTS AND METHODS

Before and after treatment, 15 patients with acromegaly underwent myocardial T2 mapping with an experimental single-breath-hold black-blood fast spin-echo sequence. Myocardial T2 mapping with both a multiple-breath-hold fast spinecho sequence and the experimental sequence also was performed on 14 volunteers. T2 relaxation times were calculated with a standard linear least-squares fit applied to myocardial signal intensity. The T2 relaxation times of patients were compared with those of volunteers and correlated with levels of serum growth hormone and insulinlike growth factor 1. Left ventricular function and mass index were determined with cine MRI.

RESULTS

T2 values before treatment were higher in patients (71 +/- 12 milliseconds) than in volunteers (55.9 +/- 3.6 milliseconds) (p = 0.0003). These T2 values in patients decreased soon after treatment (57.6 +/- 6.6 milliseconds, p = 0.0007). This reduction correlates with successful reduction of levels of serum growth hormone and insulinlike growth factor 1. In volunteers, myocardial T2 values did not vary significantly between the single-breath-hold sequence and the multiple-breath-hold fast spin-echo sequence. In patients, myocardial mass and left ventricular function did not differ significantly before and after treatment.

CONCLUSION

Patients with acromegaly have increased myocardial T2 values, which decrease soon after treatment, reflecting reversible myocardial edema. T2 value is more sensitive than left ventricular mass index in the detection of early reversal of acromegalic cardiomyopathy. These results highlight the potential role of MRI in direct assessment of the tissular effects of growth hormone and insulinlike growth factor 1 and in evaluation of the efficacy of treatment.