Table 2.
General hemodynamic characteristics and the estimated windkessel parameters
| Sheep | 1 | 2 | 3 | 4 | 5 |
|---|---|---|---|---|---|
| Number of cardiac cycles | 13 | 14 | 14 | 16 | 11 |
| Heart rate, bpm | 79.8 | 83.8 | 67.6 | 79.4 | 89.3 |
| End-diastolic P LV, mmHg | 0.7 ± 5.1 [–4.3 to 10.0] | 3.5 ± 4.1 [–1.5 to 9.9] | 3.2 ± 4.1 [–0.9 to 11.2] | 6.2 ± 2.5 [3.5 to 11.5] | 5.7 ± 3.2 [1.5 to 9.9] |
| End-systolic P LV, mmHg | 74.6 ± 12.4 [56.8 to 89.6] | 81.9 ± 9.6 [65.4 to 92.1] | 71.4 ± 4.7 [62.9 to 77.5] | 60.3 ± 3.6 [55.2 to 66.4] | 99.2 ± 9.6 [82.0 to 108.3] |
| End-diastolic V LV, mL | 60.6 ± 23.2 [30.8 to 94.3] | 66.6 ± 19.6 [39.3 to 92.9] | 48.7 ± 10.3 [35.8 to 66.0] | 78.4 ± 9.7 [64.5 to 92.4] | 87.4 ± 23.0 [49.5 to 113.0] |
| Stroke volume, mL | 38.0 ± 11.2 [22.3 to 54.7] | 40.6 ± 10.7 [27.8 to 55.7] | 27.4 ± 4.9 [20.9 to 36.1] | 34.0 ± 3.3 [29.1 to 38.6] | 46.2 ± 12.5 [25.0 to 59.6] |
| Ejection fraction | 0.65 ± 0.06 [0.56 to 0.74] | 0.62 ± 0.04 [0.58 to 0.71] | 0.57 ± 0.02 [0.54 to 0.60] | 0.43 ± 0.02 [0.41 to 0.47] | 0.53 ± 0.01 [0.51 to 0.54] |
| Maximum dP LV/dt, 103 mmHg s−1 | 1.89 ± 0.11 [1.67 to 2.01] | 1.61 ± 0.03 [1.55 to 1.65] | 1.22 ± 0.02 [1.19 to 1.24] | 0.80 ± 0.04 [0.74 to 0.86] | 1.75 ± 0.03 [1.69 to 1.78] |
| Systolic P AO, mmHg | 76.1 ± 10.5 [61.2 to 89.0] | 85.5 ± 9.2 [70.4 to 95.7] | 73.4 ± 4.5 [65.3 to 78.9] | 64.4 ± 5.8 [55.7 to 72.9] | 99.7 ± 9.2 [83.1 to 108.3] |
| Diastolic P AO, mmHg | 58.2 ± 8.5 [45.6 to 67.8] | 70.6 ± 6.8 [58.7 to 77.6] | 55.1 ± 2.2 [50.3 to 57.6] | 45.5 ± 3.7 [40.1 to 50.8] | 85.7 ± 6.6 [73.2 to 91.9] |
| Mean P AO, mmHg | 67.4 ± 10.2 [52.6 to 79.9] | 77.8 ± 8.1 [64.1 to 86.8] | 65.1 ± 3.3 [58.5 to 68.5] | 52.8 ± 5.0 [45.4 to 60.4] | 91.7 ± 8.0 [76.9 to 99.4] |
| R WK3, mmHg s mL−1 | 1.36 ± 0.23 [1.11 to 1.84] | 1.37 ± 0.19 [1.12 to 1.61] | 2.18 ± 0.24 [1.72 to 2.49] | 1.14 ± 0.03 [1.05 to 1.19] | 1.26 ± 0.21 [1.07 to 1.72] |
| C WK3, mL mmHg−1 | 1.54 ± 0.06 [1.45 to 1.65] | 1.94 ± 0.11 [1.77 to 2.16] | 0.95 ± 0.02 [0.89 to 1.00] | 1.17 ± 0.08 [1.06 to 1.36] | 2.01 ± 0.07 [1.90 to 2.10] |
| Z WK3, mmHg s mL−1 | 0.059 ± 0.015 [0.044 to 0.088] | 0.037 ± 0.008 [0.028 to 0.049] | 0.053 ± 0.007 [0.045 to 0.070] | 0.021 ± 0.004 [0.015 to 0.028] | 0.028 ± 0.006 [0.023 to 0.042] |
| RMS error, mmHg | 1.2 ± 0.1 [1.1 to 1.4] | 0.9 ± 0.1 [0.7 to 1.1] | 1.2 ± 0.2 [1.0 to 1.5] | 1.2 ± 0.2 [0.8 to 1.4] | 1.0 ± 0.1 [0.9 to 1.2] |
Values are mean ± SD [range], with the average over all cardiac cycles. Left-ventricular end-diastolic volume is not shown because simulated and measured value are equal by definition. P LV, V LV = left-ventricular pressure and volume; P AO = aortic pressure; R WK3, C WK3 and Z WK3 = peripheral resistance, arterial compliance and characteristic impedance of the windkessel model