Table 4.
Effect of amiloride or placebo on mean 24 hour heart rate variability and arrhythmia indices
| Parameter | Baseline | Placebo | Amiloride | p Value* | |
| Time domain | RR interval | 929 (149) | 945 (137) | 947 (131) | NS |
| Measures | HRV index | 28 (9) | 28 (9) | 31 (10) | NS |
| SDNN | 114 (39) | 115 (36) | 114 (35) | NS | |
| SDANN | 99 (32) | 97 (29) | 99 (35) | NS | |
| RMSSD | 26 (6) | 26 (5) | 28 (3) | NS | |
| Frequency domain | LF (n.u.) | 50 (22) | 56 (21) | 52 (23) | NS |
| Measures | HF (n.u.) | 45 (24) | 38 (22) | 42 (25) | NS |
| LF/HF | 2.9 (2.6) | 3.0 (2.8) | 2.7 (2.4) | NS | |
| 24 hour arrhythmia | ΔVE/24 hours | NA | −14 (279) | −310 (436) | <0.05 |
| Analysis | NSVT/24 hours | 0 | 0 | 0 | NS |
| Vascular collagen turnover | Serum PIIINP | 3.2 (1.0) | 3.3 (1.3) | 3.2 (0.8) | NS |
All values are expressed as mean (SD).
*Placebo versus amiloride treatment phases.
ΔVE/24 hours, change in frequency of ventricular extrasystoles over 24 hours from baseline; HF, high frequency; LF, low frequency; NSVT, non-sustained ventricular tachycardia; n.u., normalised unit; PIIINP, procollagen type III amino terminal peptide; RMSSD, root mean square of differences of successive RR intervals; SDANN, standard deviation of five minute mean RR intervals; SDNN, standard deviation of all RR intervals.