T 2 * measurement during first‐pass contrast‐enhanced cardiac perfusion imaging

First‐pass contrast‐enhanced (CE) myocardial perfusion imaging will experience T   2 *effects at peak concentrations of contrast agent. A reduction in the signal intensity of left ventricular (LV) blood due to T   2 *losses may effect estimates of the arterial input function (AIF) used for quantitative perfusion measurement. Imaging artifacts may also result from T   2 *losses as well as off‐resonance due to the bolus susceptibility. We hypothesized that T   2 *losses would not be significant for measurement of the AIF in full‐dose studies using a short echo time (TE = 0.6 ms). The purpose of this study was to directly measure T   2 *in the LV cavity during first‐pass perfusion. For single‐dose Gd‐DTPA (0.1 mmol/kg at 5 ml/s), the LV blood pool T   2 *had a mean value of 9 ms ( N = 10) at peak enhancement. Distortion of the AIF due to T   2 *signal intensity loss will be less than 10% using TE = 0.6 ms. Magn Reson Med, 2006. Published 2006 Wiley‐Liss, Inc.