The heart database: statistics



The following statistics complement the ones present in the papers.

Parameters of LV Function

Among the 18 patients, the mean LV end-diastolic volume (EDV), end-systolic volume (ESV) and the mean LV ejection fraction were 139.7 ml (range 72-219), 79.8 ml (range 20-174), and 43% (range 20-75), respectively. Mean LV myocardial mass was 123.7 g (range 94-197).

The comparisons of the mean values obtained by the 2 analyses are shown in the associated paper. The correlations for these parameters were good between the 2 methods as depicted by linear regression analysis (figure below). The regression coefficients were 0.98, 0.99, 0.99, and 0.96 for EDV, ESV, LV ejection fraction, and LV mass, respectively (all p>0.0001). Standard error estimates were 7.5 cm3, 6.7 cm3, 2.6%, and 8.3 g for EDV, ESV, LV ejection fraction, and mass, respectively.

Bland-Altman plots for comparisons of EDV, ESV, LV ejection fraction, and mass are shown in the figure below. End-diastolic and end-systolic volumes were slightly but significantly lower as assessed by the automated 4D watershed technique (-12.2 and -5.8 cm3, respectively), whereas the agreement was better for LV ejection fraction and LV mass (-0.5% and -0.4g, respectively). When comparing the traces of myocardial contours obtained by the 2 methods, the difference between manual and automatic segmentation corresponded to a shift of less than one pixel in the location of the endocardial and epicardial borders.

Linear regression


Plots showing the correlation between the conventional and the automated 4D analysis of LV function from short-axis CMR. Abbreviations. EDV: end-diastolic volume, ESV: end-systolic volume, LVEF: left ventricular ejection fraction.

Bland-Altman plots


Bland-Altman plots showing the difference of measurements between the conventional and the automated 4D analysis of LV function from short-axis CMR. Same abbreviations as the figure above.

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