Acetylcholine (ACh) endothelial-dependent and sodium nitroprusside (SNP)-independent vasodilatation in controls, patients with SSc-nonPAH, and patients with SSc-PAH at rest only. Comparisons between groups corrected for age. Data are median perfusion units.
| Group | Controls, n = 22 | SSc-nonPAH, n = 6 | SSc-PAH rest, n = 9 | Controls vs SSc-PAH rest, p | SSc-nonPAH vs SSc-PAH rest, p |
|---|---|---|---|---|---|
| ACh baseline (range) | 18.7 (8.4 to 38.5) | 23.4 (17.2 to 55.6) | 15.4 (8.1 to 43.5) | 0.25 | 0.82 |
| ACh peak (range) | 95.3 (10.8 to 225.3) | 117.8 (41.8 to 196.0) | 27.2 (15.7 to 73.0) | < 0.01 | < 0.01 |
| ACh increase (range) | 75.8 (19.7 to 209.1) | 94.1 (24.7 to 140.4) | 14.1 (1.9 to 29.6) | < 0.01 | < 0.01 |
| ACh % increase (range) | 397.9 (63.7 to 1293.4) | 340.4 (143.8 to 559.3) | 90.5 (5.51 to 209.8) | 0.02 | < 0.01 |
| SNP baseline (range) | 18.6 (5.3 to 27.7) | 27.7 (11.9 to 52.3) | 18.1 (3.6 to 34.2) | 0.40 | 0.61 |
| SNP peak (range) | 108.2 (31.5 to 202.1) | 108.3 (64.7 to 200.3) | 97.6 (23.6 to 208.9) | 0.93 | 0.66 |
| SNP increase (range) | 98.7 (13.1 to 769.0) | 88.4 (34.0 to 152.5) | 77.2 (20.0 to 195.8) | 0.77 | 0.84 |
| SNP % increase (range) | 469.3 (40.9 to 2371.9) | 431.4 (110.1 to 490.6) | 466.6 (86.2 to 1491.5) | 0.65 | 0.90 |
SSc: systemic sclerosis; PAH: pulmonary arterial hypertension.