Table 2.
Duplex ultrasound–derived variables for brachial artery reactivity testing in 34 healthy control subjects and 34 familial dysautonomia subjects with afferent autonomic failure
| Variable | Pre/post–cuff occlusion | Healthy controls (n = 34) | FD subjects (n = 34) | P value* |
|---|---|---|---|---|
| BA reactivity, % | Post–cuff occlusion | 6.27 (4.65, 9.34) | 6.00 (1.86, 11.77) | 0.75 |
| BA diameter, mm | Pre–cuff occlusion | 3.06 (2.69, 3.53) | 2.67 (2.43, 2.99) | 0.002 |
| Post–cuff occlusion | 3.30 (2.90, 3.63) | 2.83 (2.63, 3.14) | 0.004 | |
| BA diameter normalized to BSA, mm/m2 | Pre–cuff occlusion | 1.88 (1.72, 2.32) | 2.01 (1.80, 2.22) | 0.35 |
| Post–cuff occlusion | 2.03 (1.82, 2.45) | 2.18 (1.95, 2.42) | 0.22 | |
| MBFV, cm/sec | Pre–cuff occlusion | 17.6 (10.9, 25.3) | 11.9 (7.0, 15.9) | 0.01 |
| Post-cuff occlusion | 54.2 (48.3, 65.7) | 65.3 (55.5, 74.9) | 0.02 | |
| Shear rate, 1/s | Pre–cuff occlusion | 198 (106, 296) | 167 (110, 253) | 0.18 |
| Post–cuff occlusion | 705 (629, 851) | 928 (773, 1,214) | <0.001 |
Data are presented as median value (25th, 75th percentile).
Abbreviations: BA, brachial artery; BSA, body surface area; FD, familial dysautonomia; FMD, flow-mediated dilation; MBFV, mean blood flow velocity; PRH, peak reactive hyperemia.
*P values indicate comparison of familial dysautonomia subjects with healthy control subjects.