Real-time fast strain-encoded magnetic resonance imaging to evaluate regional myocardial function at 3.0 Tesla: comparison to conventional tagging.

PURPOSE

To compare the utility of the real-time technique fast strain-encoded magnetic resonance imaging (fast-SENC) for the quantification of regional myocardial function to conventional tagged magnetic resonance imaging (MRI).

MATERIALS AND METHODS

Healthy volunteers (N = 12) and patients with heart failure (N = 7) were examined using tagged MRI and fast-SENC at 3.0T. Circumferential strain was measured using fast-SENC in six endo- and six subepicardial regions in the basal-, mid-, and apical-septum and the basal-, mid-, and apical-lateral wall from the four-chamber view. These measurements were plotted to tagging, in corresponding myocardial segments.

RESULTS

Peak systolic strain (Ecc) and early diastolic strain rate (Ecc/second) acquired by fast-SENC correlated closely to tagged MRI (r = 0.90 for Ecc and r = 0.91 for Ecc/second, P < 0.001 for both). Both fast-SENC and tagging identified differences in regional systolic and diastolic function between normal myocardium and dysfunctional segments in patients with heart failure (for fast-SENC: Ecc = -21.7 +/- 2.7 in healthy volunteers vs. -12.8 +/- 4.2 in hypokinetic vs. 0.6 +/- 3.8 in akinetic/dyskinetic segments, P < 0.001 between all; Ecc/second = 104 +/- 20/second in healthy volunteers vs. 37 +/- 9/second in hypokinetic vs. -16 +/- 15/second in akinetic/dyskinetic segments, P < 0.001 between all). Quantitative analysis was more time-consuming for conventional tagging than for fast-SENC (time-spent of 3.8 +/- 0.7 minutes vs. 9.5 +/- 0.7 minutes per patient, P < 0.001).

CONCLUSION

Fast-SENC allows the rapid and accurate quantification of regional myocardial function. The information derived from fast-SENC during a single heartbeat seems to be superior or equal to that acquired by conventional tagging during several heart cycles and prolonged breathholds.