Fig. 1

Cardiac catheterisation data: On presentation (left), the cardiac catheter measured a PVRI of 6.5 WU.m² on air and 4.8 WU.m² after nitric oxide (NO). The patient was therefore in the borderline “grey zone” for defect closure, according to current PH guidelines. Three years after closure of the VSD, PVRI had risen to 13.4 WU.m², dropping to 8 WU.m² with NO. Twelve years later, 3 months after delivery, the PVRI had doubled to 26 WU.m² with no reversibility