Table 2.
Effects of hypoxia on in vivo heart function of full-term fetal guinea pigs
| Normoxia (n = 21) | Hypoxia (n = 17) | |
|---|---|---|
| Maternal HR, beats/min | 180.6 ± 8.6 | 161.1 ± 6.2 |
| Fetal HR, beats/min | 196.1 ± 6.2 | 209.8 ± 6.7 |
| Systolic function | ||
| IVCT, ms | 0.026 ± 0.001 | 0.030 ± 0.003 |
| ET, ms | 0.126 ± 0.005 | 0.132 ± 0.005 |
| IVRT, ms | 0.046 ± 0.002 | 0.050 ± 0.003 |
| Tie index | 0.577 ± 0.019 | 0.622 ± 0.027 |
| Diastolic function | ||
| Mitral valve | ||
| E wave velocity | 20.4 ± 1.3 | 24.4 ± 2.3* |
| E/A ratio | 0.60 ± 0.03 | 0.72 ± 0.04* |
| Tricuspid valve | ||
| E wave velocity | 22.4 ± 1.5 | 30.5 ± 4.1 |
| A wave velocity | 33.0 ± 2.0 | 45.1 ± 6.0 |
| E/A ratio | 0.711 ± 0.035 | 0.66 ± 0.02 |
| Outflow-left | ||
| Aorta | ||
| Diameter, cm | 0.194 ± 0.006 | 0.203 ± 0.008 |
| CSA, cm3 | 0.030 ± 0.002 | 0.033 ± 0.003 |
| Vmax, cm/s | 43.45 ± 3.04 | 58.82 ± 14.81 |
| Flow, cm3/ms | 1.209 ± 0.149 | 1.654 ± 0.378 |
| Outflow-right | ||
| Pulmonary artery | ||
| Diameter, cm | 0.205 ± 0.007 | 0.190 ± 0.010 |
| CSA, cm3 | 0.034 ± 0.002 | 0.030 ± 0.003 |
| Vmax, cm/s | 48.05 ± 3.88 | 47.74 ± 10.05 |
| Flow, cm3/s | 1.66 ± 0.21 | 1.46 ± 0.31 |
Values are means ± SE. HR, heart rate; IVCT, intraventricular contraction time; IVRT, intraventricular relaxation time; ET, ejection time; Tie index, IVCT + IVRT/ET; CSA, cross-sectional area; Vmax, maximal flow velocity. All groups were compared using Student’s t-test.
*
P < 0.05 vs. normoxia.