Three-dimensional analysis of regional left ventricular endocardial curvature from cardiac magnetic resonance images

Purpose

Left ventricular (LV) remodeling is usually assessed using global changes in LV volume. We hypothesized that three-dimensional analysis of regional endocardial curvature from magnetic resonance images could provide clinically useful information on localized LV remodeling. We tested this approach by investigating regional differences in endocardial curvature in normal and hypokinetic ventricles.

Materials and Methods

Images were obtained in 44 patients with normal LV function (NL, N=14), dilated cardiomyopathy (DCM, N=15) or ischemic heart disease (IHD, N=15). Local surface curvedness, normalized to take into account instantaneous LV size (C_n), was calculated throughout the cardiac cycle and compared between segment groups: NL (N=401), IHD (N=92) and DCM (N=255).

Results

In all normal segments, C_n gradually increased during systole and then decreased during diastole. While both maximum and minimum values of C_n were comparable in the basal and midventricular segments, they were significantly higher in the four apical segments and highest in the apical cap. In addition, percent change in C_n was higher in mid and apical compared to basal segments (P<.05). At all LV levels, C_n values in DCM segments were lower (P<.05) than in NL and IHD segments, which were similar. In contrast, percent change in C_n was significantly lower in both IHD and DCM segments compared to NL.

Conclusion

Three-dimensional analysis of LV endocardial curvature yielded quantitative information on regional ventricular shape consistent with the known pathophysiology, supporting its potential clinical usefulness in the evaluation of LV remodeling.