Review the diagnostic pathway for pulmonary arterial hypertension (PAH) in congenital heart disease (CHD).

Understand and interpret right heart catheterisation data in pulmonary hypertension related to CHD.

Recognise the typical presentation of PAH in patients with CHD.

Explore the treatment options for PAH-CHD.

Review and understand the management of common emergencies in PAH-CHD.

Pulmonary hypertension (PH) is defined as a mean pulmonary arterial pressure (PAP) above 20 mm Hg, determined by right heart catheterisation. PH is classified into five distinct groups based on underlying pathophysiology and haemodynamics (figure 1).1 2 Patients with pulmonary arterial hypertension (PAH) have precapillary PH haemodynamics, defined as a mean PAP above 20 mm Hg, a pulmonary vascular resistance (PVR) >2 Wood units (WU) and a pulmonary capillary wedge pressure (PCWP) ≤15 mm Hg.2 PAH encompasses conditions with similar pathophysiological characteristics of the pulmonary circulation, and includes PAH associated with congenital heart disease (PAH-CHD), which is the focus of this article (figure 2) 2. PAH affects approximately 10% of patients with CHD, and PAH-CHD accounts for almost a third of the adult PAH population.3 Delays in the diagnosis of PAH can be avoided if patients with CHD are regularly monitored in specialist tertiary centres, where clinicians are vigilant to all complications of CHD.2 4 5

Subgroups of pulmonary hypertension. CHD, congenital heart disease; CTD, connective tissue disease; CTEPH, chronic thromboembolic pulmonary hypertension; CVD, cardiovascular disease; HFpEF, heart failure with preserved ejection fraction; HFrEF, heart failure with reduced ejection fraction; PA, pulmonary artery; PAH, pulmonary arterial hypertension; PCH, pulmonary capillary haemangiomatosis; PH, pulmonary hypertension; PPHN, persistent pulmonary hypertension of the newborn; PVOD, pulmonary veno-occlusive disease. 2

Pulmonary hypertension classification based on right heart catheterisation. ASD, atrial septal defect; Cpc, combined precapillary and postcapillary pulmonary hypertension; mPAP, mean pulmonary artery pressure; PCWP, pulmonary capillary wedge …