Table 3 Parameters of the static characteristics of the carotid sinus baroreflex
|  | Control (n = 12) | CHF (n = 7) | P value |
|---|---|---|---|
Neural arc | |||
 P1, response range (%) | 62 ± 4 | 42 ± 6** | 0.008 |
 P2, slope coefficient (mmHg−1) | 0.10 ± 0.01 | 0.16 ± 0.03* | 0.048 |
 P3, midpoint pressure (mmHg) | 128 ± 4 | 115 ± 4* | 0.043 |
 P4, minimum SNA (%) | 39 ± 4 | 60 ± 6** | 0.008 |
 Maximum slope (% mmHg−1) | 1.62 ± 0.27 | 1.54 ± 0.27 | 0.839 |
Peripheral arc | |||
 a, slope (mmHg %−1) | 1.10 ± 0.08 | 0.75 ± 0.10* | 0.013 |
 b, AP intercept (mmHg) | 23.5 ± 7.7 | 40.7 ± 7.2 | 0.152 |
Total baroreflex | |||
 P1, response range (mmHg) | 64 ± 4 | 31 ± 6** | <0.001 |
 P2, slope coefficient (mmHg−1) | 0.10 ± 0.01 | 0.13 ± 0.01 | 0.144 |
 P3, midpoint pressure (mmHg) | 122 ± 3 | 117 ± 4 | 0.326 |
 P4, minimum AP (mmHg) | 74 ± 4 | 85 ± 3 | 0.065 |
 Maximum gain | 1.62 ± 0.22 | 0.95 ± 0.17* | 0.048 |
Heart rate control | |||
 P1, response range (beats min−1) | 49 ± 5 | 30 ± 6* | 0.033 |
 P2, slope coefficient (mmHg−1) | 0.10 ± 0.01 | 0.13 ± 0.01 | 0.099 |
 P3, midpoint pressure (mmHg) | 131 ± 4 | 117 ± 4* | 0.046 |
 P4, minimum HR (beats min−1) | 383 ± 7 | 343 ± 13* | 0.011 |
 Maximum slope (beats min−1 mmHg−1) | 1.28 ± 0.23 | 0.93 ± 0.20 | 0.313 |
Equilibrium diagram | |||
 Operating-point AP (mmHg) | 116 ± 3 | 106 ± 3* | 0.042 |
 Operating-point SNA (%) | 84 ± 3 | 90 ± 4 | 0.227 |
 Operating-point total baroreflex gain | 1.23 ± 0.28 | 0.96 ± 0.39 | 0.578 |