Evaluation of Latent Pulmonary Arterial Hypertension in Congenital Shunt Lesions

Pulmonary arterial hypertension (PAH) in patients with congenital heart disease (CHD) usually develops secondary to chronic volume overload of the pulmonary circulation following left to right shunt. This overload leads to elevated pulmonary artery pressure (PAP) and later to increased pulmonary vascular resistance (PVR). This causes pressure overload in the right heart, and thereby right ventricular (RV) and right atrial (RA) dysfunction, which may implicate considerable morbidity and even mortality. Since PAH nowadays is mostly detected when symptoms occur and PAP are elevated, the disease already evolved to an advanced (partially irreversible) stage and treatment is often initiated too late.

Dismissal from follow-up after a surgical correction of simple CHD was customized in the seventies and eighties. There is no literature available that learns us whether these patients really need follow-up or not. A substantial number must have insidiously developed PAH or mild pulmonary vascular disease (PVD) and still are prone to develop PAH later in life. It is relevant to recall these patients dismissed from follow-up in the past, because they might carry a lot of useful information on the natural history of PAH development. Focus will lie mainly on patients with simple shunt lesions, as atrial septal defect (ASD) and ventricular septal defect (VSD).