Invasive Validation of Antares, a New Algorithm to Calculate Central Blood Pressure from Oscillometric Upper Arm Pulse Waves

Figures

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  Figure 1. (a) Original oscillometric recording of a 65-year-old lady showing raw data during inflation and deflation of the oscillometric cuff. (b) Extracted oscillometric pulse waves of the same 65-year old lady during deflation of the cuff. The following signals are displayed: cuff pressure (cuff), extracted oscillometrical pulse waves (osci), and foot points for each identified pulse wave (foot) over time in seconds (s).

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  Figure 2. (a) Invasive raw data of the same 65-year-old lady. Over 90 s, a total of two pulse waves had to be excluded (at 18 s). All other pulse waves were included in the analysis of central BP. (b) Enlarged section of the invasive recording of pulse waves of the same 65-year-old lady. The points mark systolic and diastolic blood pressure.

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  Figure 3. Distribution of the central blood pressures (BP) of the same 65-year-old lady, extracted from the invasive recordings with (from left to right) central diastolic BP, central mean arterial pressure, and central systolic BP.

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  Figure 4. Scatter plot of estimated versus invasive central systolic blood pressure (SBP). Dashed line: line of identity; dotted line: trend line.

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  Figure 5. Bland–Altman of estimated versus invasive central systolic blood pressure (SBP). Dashed line (dark): confidence interval/upper and lower limits with mean ±1.96*standard deviation (SD); dashed line (light): mean value; dotted line: trend line of the scatter plot. Correlation of the coefficient of determination: r2 = 0.86; correlation: r = 0.93; mean: 0.71 mmHg; standard deviation: 5.95 mmHg; confidence interval 95%: −10.95/+12.37 mmHg (mean + 1.96*SD).

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  Figure 6. Scatter plot of estimated versus invasive central mean blood pressure (MAP). Dashed line: line of identity; dotted line: trend line.

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  Figure 7. Bland–Altman of estimated versus invasive central mean blood pressure (MAP). Dashed line (dark): confidence interval/upper and lower limits with mean ±1.96*SD; dashed line (light): mean value; dotted line: trend line of the scatter plot. Correlation of the coefficient of determination: r2 = 0.84; correlation: r = 0.92; mean: 0.19 mmHg; standard deviation: 3.78 mmHg; confidence interval 95%: −7.21/+7.59 mmHg (mean + 1.96*SD).

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  Figure 8. Scatter plot of estimated versus invasive central diastolic blood pressure (DBP). Dashed line: line of identity; dotted line: trend line.

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  Figure 9. Bland–Altman of estimated versus invasive central diastolic blood pressure (DBP). Dashed line (dark): confidence interval/upper and lower limits with mean ±1.96*SD; dashed line (light): mean value; dotted line: trend line of the scatter plot. Correlation of the coefficient of determination: r2 = 0.71; correlation: r = 0.84; mean: 2.96 mmHg; standard deviation: 5.21 mmHg; confidence interval 95%: −7.25/+13.17 mmHg (mean + 1.96*SD).