Measurements of left ventricular dimensions using real-time acquisition incardiac magnetic resonance imaging: comparison with conventional gradient echo imaging

This study investigates the use of real-time acquisition in cardiac magneti c resonance imaging (MRI) for measurements of left ventricular dimensions i n comparison with conventional gradient echo acquisition. Thirty-one subjec ts with a variety of left ventricular morphologies to represent a typical c linical population were studied. Short-axis data sets of the left ventricle (LV) were acquired using a conventional turbo-gradient echo and an ultrafa st hybrid gradient echo/echo planar sequence with acquisition in real-time. End-diastolic volume (EDV), end-systolic volume (ESV), ejection fraction ( EF) and left ventricular mass (LV mass) were measured. The agreement betwee n the two acquisitions and interobserver, intraobserver and interstudy vari abilities were determined. The bias between the two methods was 5.86 ml for EDV, 0.23 ml for ESV and 0.94% for EF. LV mass measurements were significa ntly lower with the real-time method (mean bias 14.38 g). This is likely to be the result of lower spatial resolution and chemical shift artefacts wit h the real-time method. Interobserver, intraobserver and interstudy variabi lities were low for all parameters. In conclusion, real time acquisition in MRI can provide accurate and reproducible measurements of LV dimensions in subjects with normal as well as abnormal LV morphologies, but LV mass meas urements were lower than with conventional gradient echo imaging. (C) 2001 Elsevier Science B.V. All rights reserved.