Table 2.
VCM versus intra-arterial blood pressure measurements
| VCM (mmHg) | Intra-arterial (mmHg) | Mean difference (mmHg) | Limits of agreement (bias ± 2 SD; mmHg) | Percentage error (%) | r² (p-value) | ICC | |
|---|---|---|---|---|---|---|---|
| Atrial fibrillation (n = 31) | |||||||
| Systolic blood pressure | 111 (22) | 115 (20) | −4 (12) | −28 to 20 | 21 | 0.70 (<0.01) | 0.82 |
| Diastolic blood pressure | 65 (10) | 64 (11) | 1 (7) | −13 to 15 | 22 | 0.61 (<0.01) | 0.77 |
| Mean blood pressure | 81 (13) | 81 (13) | 0 (8) | −15 to 15 | 18 | 0.70 (<0.01) | 0.84 |
| Absolute beat-to-beat systolic blood pressure difference | 4.5 (1.8–10.5) | 5.0 (2.0–11.3) | 1.5 (0.5–3.8) | −11 to 11 | NA | 0.81 (<0.01) | 0.89 |
| Sinus rhythm (n = 10) | |||||||
| Systolic blood pressure | 110 (22) | 116 (22) | −6 (10) | −26 to 15 | 18 | 0.78 (<0.01) | 0.85 |
| Diastolic blood pressure | 67 (9) | 62 (10) | 4 (6) | −7 to 16 | 19 | 0.67 (<0.01) | 0.73 |
| Mean blood pressure | 82 (12) | 81 (14) | 1 (5) | −10 to 11 | 13 | 0.87 (<0.01) | 0.92 |
| Absolute beat-to-beat systolic blood pressure difference | 2.0 (0.75–4.3) | 2.5 (1.0–5.3) | 1.0 (0.5–1.8) | −4 to 7 | NA | 0.71 (<0.01) | 0.82 |
All data are displayed as mean (SD) or median (interquartile range)
VCM volume-clamp method, SD standard deviation, r correlation coefficient, ICC intra-class correlation