Quantification of left ventricular function with magnetic resonance imagesacquired in real time

The application of real-time magnetic resonance imaging (MRI) techniques to cardiac imaging is particularly attractive because current MR examinations of left ventricular (LV) function can be prohibitively long and are depend ent on electrocardiographic triggering. We conducted a study of the minimum spatial and temporal resolution requirements necessary for real-time ventr icular function MR imaging to quantify LV volumes accurately, both at resti ng conditions and during cardiac stress tests. In addition, we implemented a real-time segmented echoplanar imaging pulse sequence and used it to quan tify LV volume in 10 healthy volunteers. We compared these results with tho se obtained using conventional gradient-echo cine imaging and found good ag reement throughout the cardiac cycle (mean difference -0.8 +/- 10.6 ml). In conclusion, realtime cardiac MR imaging can be used to quantify LV volumes accurately throughout the cardiac cycle, over the physiologic range of hea rt rates, thereby decreasing the time required for a complete functional ca rdiac examination. (C) 2000 Wiley-Liss, Inc.