TABLE 2.
Clinical, biometric, echocardiographic, and cardiac MRI assessed parameters across assessments in the switch group summarized as mean ± standard deviation.
| Primary assessment: Baseline assessment to switch completion assessment | Switch phase 1: Baseline assessment to post ERA switch assessment | Switch phase 2: post ERA switch assessment to switch completion assessment | |||||||
|---|---|---|---|---|---|---|---|---|---|
| Bosentan + sildenafil switched to ambrisentan + tadalafil | Bosentan + sildenafil switched to ambrisentan + sildenafil | Ambrisentan + sildenafil switched to ambrisentan + tadalafil | |||||||
| n | Δ | p | n | Δ | p | n | Δ | p | |
| WHO FCa | |||||||||
| III/IV (%) | ‐ | 48 vs. 13a | <0.01 | ‐ | 48 vs. 16 | <0.01 | ‐ | 16 vs. 13 | 0.73 |
| Exercise assessment | |||||||||
| 6MWD (m) | 23 | 7 [−21, 35] | 0.62 | 27 | −8 [−32, 16] | 0.51 | 23 | 21 [5,37] | 0.01 |
| VE/VCO2 slope | 25 | −3.5 [−7.1, 0.1] | 0.06 | ||||||
| VE/VCO2 slope % changeb | 25 | −7 [−14.4, 0.3] | 0.06 | ||||||
| Peak VO2 (L/min/m2) | 25 | 0.6 [−1.7, 2.9] | 0.60 | ||||||
| Peak VO2% changeb | 25 | 3.4 [−7.6, 14.4] | 0.53 | ||||||
| Biochemical measure | |||||||||
| NT‐proBNP ratioc | 26 | 0.96 [0.83, 1.10] | 0.55 | 25 | 1.00 [0.89, 1.13] | 0.97 | 26 | 0.93 [0.85, 1.01] | 0.08 |
| Echocardiographic parameters | |||||||||
| RAA (cm2) | 17 | 0.2 [−1.1, 1.6] | 0.72 | 16 | 0.1 [−1.1, 1.4] | 0.84 | 19 | 0.7 [−0.2, 1.7] | 0.13 |
| RVSP (mmHg) | 27 | −7 [−13, −1] | 0.03 | 29 | ‐8 [−14, −3] | <0.01 | 26 | 3 [−3, 9.0] | 0.3 |
| Eccentricity index diastole | 27 | −0.007 [−0.09, 0.08] | 0.87 | 26 | 0.07 [−0.05, 0.19] | 0.22 | 26 | −0.11 [−0.25, 0.03] | 0.13 |
| Eccentricity index systole | 28 | 0.01 [−0.18, 0.16] | 0.90 | 26 | −0.01 [−0.20, 0.18] | 0.90 | 26 | 0.02 [−0.25, 0.29] | 0.89 |
| TAPSE (mm) | 28 | 0.02 [−1.4, 1.5] | 0.98 | 29 | 0.16 [−0.8, 1.2] | 0.74 | 29 | 0.1 [−1.6, 1.7] | 0.95 |
| Cardiac MRI parameters | |||||||||
| RVEDVi (mL/m2) | 30 | 5.7 [0.8, 10.6] | 0.02 | 29 | 3.3 [0.6, 6.1] | 0.02 | 27 | 2.9 [−1.9, 7.6] | 0.23 |
| RVEF (%) | 30 | 1.8 [0.2, 3.5] | 0.03 | 29 | 1.1 [−0.3, 2.5] | 0.11 | 27 | 0.3 [−1.5, 2.0] | 0.76 |
| Estimated mPAP (mmHg) | 28 | 0.7 [−4.7, 3.4] | 0.74 | 26 | 0.3 [−3.5, 4.1] | 0.88 | 25 | −0.6 [−4.3, 3.1] | 0.73 |
Note: Comparison of parameters between assessments summarized as difference, Δ, confidence interval, [], number of paired pre/post data, n, and p value, p. Except for: ** comparison between % of children with the same or improved WHO FC and those with a worse WHO FC. Statistically significant p values (<0.05) are shown in bold font.
Key: Echocardiographic parameters: LVEI, left ventricular eccentricity index; RAA, right atrial area; RVSP, estimate of right ventricular systolic pressure on echocardiography; TAPSE, tricuspid annular plane systolic excursion. Cardiac magnetic resonance imaging (MRI) parameters: est. mPAP, estimated mean pulmonary artery pressure; RVEDVi, right ventricular end‐diastolic volume indexed to body surface area; RVEF, right ventricular ejection fraction. Cardio‐pulmonary exercise parameters: VO2, oxygen consumption; VE/VCO2, ventilatory efficiency slope. NT‐proBNP, N‐terminal pro‐B‐type natriuretic peptide. WHO FC, World Health Organization functional class.
% of children in FC III or IV in those assigned.
VE/VCO2 slope % change and VO2% change are represented as means.
NT‐proBNP is represented as the difference in geometric means and is expressed as a ratio.