Table 1.
No effect of acidosis and hyperkalemia in the superfusate on the loss of excitability and the time of VF onset during global ischemia in 200ms_Iso group
| Superfusion Composition | Hypoxic | Hypoxic, Acidic, Hyperkalemic |
|---|---|---|
| Time of 10% excitability loss | ||
| RV | 10.5 ± 0.6 | 10.6 ± 2.4 |
| LV | 8.9 ± 0.6 | 7.1 ± 0.9 |
| Time of 50% excitability loss | ||
| RV | 13.5 ± 0.9 | 14.0 ± 3.0 |
| LV | 10.9 ± 0.9 | 10.9 ± 2.11 |
| Time to VF | 9.9 ± 0.9 | 10.2 ± 1.1 |
Time values are means ± SE and are in minutes; n = 6 for Hypoxic group, and n = 5 for Hypoxic, Acidic, Hyperkalemic group. The hearts were subjected to rapid pacing (cycle length = 200 ms), isoproterenol (30 nM), and global no-flow ischemia. In hypoxic superfusion, pO2 was below 40 mmHg, but otherwise the solution had normal composition. In hypoxic, acidic, hyperkalemic solution, pO2 was reduced to 25 mmHg, pH was reduced to 6.8, and [K+]o was elevated to 8 mM. VF, ventricular fibrillation; RV, right ventricular; LV, left ventricular. All differences, P > 0.1 by unpaired 2-tailed Student test.