Quantification of left ventricular ejection fraction and cardiac output using a novel semi-automated echocardiographic method: a prospective observational study in coronary artery bypass patients

Figures

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  Fig. 1. Patient selection and study flow diagram. TOE: transoesophageal echocardiography, TTE: transthoracic echocardiography

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  Fig. 2. A Ejection fraction determined by transthoracic biplane AutoEF and TOE using the modified Simpson’s method. Box-and-whiskers plots show the first (bottom), second (inner line indicating median), and third (top) quartile. The whiskers represent the limits of 1.5 times the interquartile range. Outliers are depicted as circles below and above these limits. * p < 0.01. B Linear correlation of biplane EF determined by AutoEF and TOE using the modified Simpson’s method (r = 0.38, p < 0.01). Solid line represents the regression curve, dashed lines the mean confidence interval. C Bland–Altman plot for comparison of EF by biplane AutoEF and TOE using the modified Simpson’s method. Bias: -12.6%, 95%LOA: -36.5 — 11.3%. Solid line represents bias, dashed lines show the 95% limits of agreement (95%LOA). Data show a systematic EF underestimation by AutoEF. EF: ejection fraction, TOE: transoesophageal echocardiography

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  Fig. 3. A Left ventricular end systolic (LVESV) and end diastolic volumes (LVEDV) as determined by biplane transthoracic AutoEF (yellow) and TOE using the modified Simpson’s method (blue). Box-and-whiskers plots show the first (bottom), second (inner line indicating median), and third (top) quartile. The whiskers represent the limits of 1.5 times the interquartile range. Outliers are depicted as circles below and above these limits, asterisks represent extreme outliers. * p < 0.01. B Bland–Altman plot for comparison of left ventricular end diastolic volumes determined by biplane transthoracic AutoEF and TOE using the modified Simpson’s method. Bias: 29.8 ml, 95%LOA: -45.3 — 105 ml. Solid line represents bias, dashed lines show the 95% limits of agreement (95%LOA). C Bland–Altman plot for comparison of left ventricular end systolic volumes as determined by biplane transthoracic AutoEF and TOE using the modified Simpson’s method. Bias: 28.1 ml, 95%LOA: -18.2 – 74,5 ml. Solid line represents bias, dashed lines show the 95% limits of agreement (95%LOA). EF: ejection fraction, TOE: transoesophageal echocardiography, LVEDV: left ventricular end diastolic volume, LVESV: left ventricular end…

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  Fig. 4. Cardiac output measurements by TTE AutoEF, TOE VTILVOT, and PAC thermodilution. Boxes show the first (bottom), second (inner line indicating median) and third (top) quartile. The whiskers represent the limits of 1.5 times the interquartile range. Outliers are depicted as circles below and above these limits. The asterisk represents an extreme outlier. * p < 0.01. TOE: transoesophageal echocardiography, VTI: velocity time integral, LVOT: left ventricular outflow tract

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  Fig. 5. Linear correlations (A, C, E) and corresponding Bland–Altman plots (B, D, F) comparing cardiac output measurements by TTE AutoEF, TOE VTILVOT, and thermodilution. For correlations, the solid lines represent the regression curves and dashed lines the mean confidence intervals. For Bland–Altman plots, the solid lines represent the bias and dashed lines show the 95% limits of agreement (95%LOA). CO: cardiac output, TOE: transoesophageal echocardiography, VTI: velocity time integral, LVOT: left ventricular outflow tract, TDCO: thermodilution cardiac output