Table 2.
Action potential parameters of ventricular-like human induced pluripotent stem cell cardiomyocytes treated with ML277
| Spontaneous APs | APA (mV) | APD50 (ms) | APD90 (ms) | APD90/APD50 | Overshoot (mV) | MDP (mV) | Heart rate (beats/minute) | |
|---|---|---|---|---|---|---|---|---|
| LQT1 patient | Baseline (n = 11) | 98.4 ± 1.7 | 601.1 ± 51.1 | 665.4 ± 51.9 | 1.12 ± 0.01 | 40.1 ± 2.4 | −60.9 ± 1.6 | 64.6 ± 6.0 |
| ML277 (1 μM) (n = 11) | 98.1 ± 1.3 | 455.5 ± 44.6** | 514.7 ± 46.0** | 1.15 ± 0.02 | 38.0 ± 2.8 | −61.1 ± 1.7 | 66.9 ± 1.6 | |
| Control (father) | Baseline (n = 9) | 99.1 ± 3.5 | 315.1 ± 23.1 | 368.8 ± 22.5 | 1.13 ± 0.01 | 41.5 ± 1.1 | −59.4 ± 1.1 | 75.8 ± 6.8 |
| ML277 (1 μM) (n = 9) | 99.2 ± 2.4 | 228.0 ± 24.4** | 288.4 ± 27.4** | 1.17 ± 0.02 | 40.7 ± 2.7 | −60.6 ± 1.5 | 76.0 ± 8.0 | |
AP, action potential; APA, action potential amplitude; APD50, action potential duration at 50% repolarization; APD90, action potential duration at 90% repolarization; LQT1, type 1 long QT syndrome; MDP, maximum diastolic potential. **P <0.01, versus baseline.