Biplane Long-axis Magnetic Resonance Imaging. Survey Projections for Rapid Estimation of Left Ventricular Mass and Global Function

Abstract

Objective –To evaluate the accuracy and precision of biplane long-axis magnetic resonance imaging (MRI) and two-dimensional (2D)-echocardiography, for the assessment of left ventricular (LV) mass and volumes, with multislice short-axis MRI as reference standard. Design –Forty-five cardiac patients and four volunteers with varying LV dilatation and hypertrophy were examined by biplane long-axis gradient-echo MRI, 2D-echocardiography, and multiple short-axis gradient-echo MRI. Results –Compared with multislice MRI, the accuracy, i.e. the coefficient of variation (c.v.) of inter-method differences of measured variables, was median 15.7% for biplane MRI and 18.5% for 2D-echocardiography. The precision, expressed as the c.v. of repeated measurements, was median 8.5% for multislice MRI, 9.5% for biplane MRI and 12.4% for 2D-echocardiography. For the determination of LV mass index, MRI was significantly more precise (c.v.: 6.0-8.4%) than 2D-echocardiography (c.v.: 13.7-14.3%, p < 0.05). Conclusion –Biplane long-axis MRI is a fast and simplified method, offering the advantage of displaying anatomy and function in recognizable projections. For the estimation of LV mass and volumes, biplane MRI had an acceptable accuracy, and a precision that did not differ significantly from that of multislice MRI.