Dual-standard reference values of left ventricular volumetric parameters by multidetector CT angiography

Background: The papillary and trabecular muscles constitute a significant percentage of left ventricular mass and volume. The influence of the papillary and trabecular muscles on left ventricular parameters has not been described with multidetector CT angiography.

Objective: The aims of this study are (1) to derive reference values for left ventricular volumetric parameters both including and excluding the papillary and trabecular muscles and (2) to establish the optimal segmentation method for measuring these values.

Methods: A total of 179 subjects (mean age, 55.4 ± 9 years; 102 women) without heart disease and at low risk of cardiovascular disease who underwent CT angiography were selected. Left ventricular volumes, myocardial volume, and ejection fraction were measured with epicardial and 2 endocardial trace methods, including and excluding trace for the papillary and trabecular muscles. Values of all parameters obtained by both endocardial trace methods were compared.

Results: Significant difference between both trace groups for all parameters on both sexes was found (P < .001). Significant differences in precision error of remeasurement were found in the including trace (3.6%) compared with the excluding trace (4.7%; P < .05) and in the epicardial trace (2.2%) compared with both endocardial traces (P < .001).

Conclusion: The left ventricular parameters measured by CT angiography were influenced significantly by the trace method by including or excluding the papillary and trabecular muscles. The dual-standard reference values of left ventricular parameters were established, and the optimal segmentation methods were definite in considering the heart size and image quality studied with retrospective and prospective CT angiography.