Estimation of left ventricular mass in humans with MR imaging: Accuracy and reproducibility

The authors show that MR imaging provides an accurate and reproducible estimate of left ventricular (LV) mass in man. Short-axis images spanning the left ventricle were used to determine the total LV wall volume (LVWV) using Simpson's rule. Multiplying LVWV by the density of myocardium, an estimate of LV mass was obtained. Using formalin-fixed specimens, a regression equation was derived: MR LV mass (grams) = 1.08 x LV weight - 4.7, n=10, r=.99, SEE=7.4g. End-diastolic images were obtained in vivo in 40 subjects with LV masses between 156.4 and 319.3 g. The intraobserver and interobserver variabilities for the in vivo studies were r=.96, SEE=11.1g, n=10, and r=.91, SEE=16.9g, n=10, respectively. Eight subjects were again imaged 1 to 14 days later and good reproducibility was also obtained