Technical feasibility of semiautomatic three-dimensional threshold-based cardiac computed tomography quantification of left ventricular mass.

Abstract

Semiautomatic three-dimensional (3-D) threshold-based cardiac computed tomography (CT) quantification has not been attempted for left ventricular mass. To evaluate the technical feasibility of semiautomatic 3-D threshold-based cardiac CT quantification of left ventricular mass in patients with various degrees of left ventricular hypertrophy. In 99 patients, cardiac CT was utilized to quantify ventricular volume and mass by using a semiautomatic 3-D threshold-based method. Left ventricular mass values were compared between the end-systole and the end-diastole. Volumetric parameters were compared among three left ventricular hypertrophy groups (definite, borderline, none). The reproducibility was assessed. The t-test, one-way analysis of variance and Pearson correlation were used. There were no technical failures. The left ventricular mass between the two sessions exhibited a small mean difference of 2.3±1.1% (mean±standard deviation). The indexed mass values were significantly higher at the end-systole than at the end-diastole (71.4±42.9g/m2 vs. 65.9±43.3g/m2, P<0.001), with significant correlation (R=0.99, P<0.001). The definite group (83.5±41.3g/m2) showed statistically significantly higher indexed mass values than the borderline and none groups (64.7±26.9 and 55.6±23.9g/m2, respectively; P<0.03), while demonstrating no statistically significant difference between the latter two groups (P>0.05). Left ventricular volume-mass and mass-volume ratios could be calculated in all three groups. CT quantification of left ventricular mass using semiautomatic 3-D threshold-based segmentation is feasible with high reproducibility and the mass values and its ratios with ventricular volumes may be used in patients with various degrees of left ventricular hypertrophy.