Measurement of human myocardial perfusion by double-gated flow alternatinginversion recovery EPI

This paper presents a flow-sensitive alternating inversion recovery (FAIR) method for measuring human myocardial perfusion at 1.5 T. Slice-selectiveln on-selecfive IR images were collected using a double-gated IR echoplanar im aging sequence. Myocardial perfusion was calculated after T1 fitting and ex trapolation of the mean signal difference SISel - SINSel. The accuracy of t he method was tested in a porcine model using graded intravenous adenosine dose challenge. Comparison with radiolabeled microsphere measurements showe d a good correlation (r = 0.84; mean error = 20%, n = 6) over the range of flows tested (0.9-7 ml/g/min). Applied in humans, this method allowed for t he measurement of resting myocardial flow (1.04 +/- 0.37 ml/g/min, n = 11). The noise in our human measurements (SEflow = 0.2 ml/g/min) appears to com e primarily from residual respiratory motion. Although the current signal-t o-noise ratio limits our ability to measure small fluctuations in resting f low accurately the results indicate that this noninvasive method has great promise for the quantitative assessment of myocardial flow reserve in human s. Magn Reson Med 41:510-519, 1999. (C) 1999 Wiley-Liss, Inc.