Grouping of samples used for immunohistochemistry
| Diagnostic groups | No of cases | Age range | Median Age per group | Origin of sample | ||
| Biopsy (treated/untreated) | Transplant (treated/untreated) | Postmortem (treated/untreated) | ||||
| Idiopathic pulmonary arterial hypertension | 15 | 3–16 years | 8 years | 3 (0/3) | 8 (6/2) | 4 (0/4) |
| Pulmonary hypertensive congenital heart disease | 9 | 6 months–16 years | 7 years | 6 | 2 | 1 |
| Normal pulmonary vasculature ± infection | 9 | 3 months–29 years | 8 years | 9 | ||