P2 is increased and moves closer to A2 as the pulmonary pressures increase. Eventually S2 may be fixed and paradoxically split. Increased right atrial pressures may lead to dependent edema, hepatojugular reflux, and ascites. The chest x-ray may reveal right ventricular hypertrophy, manifest as filling of the retrocardiac space on the lateral film, and increased PA size. The ECG may be normal or show right atrial and ventricular enlargement as well as an R axis deviation.
Supraventricular tachycardias are common.
Diagnosis is often expected based on clinical examination although findings may be subtle. The diagnosis is confirmed with right heart catheterization which demonstrates elevated right atrial, ventricular and pulmonary artery pressures. Left atrial pressure is normal unless there is mitral stenosis or left ventricular failure. In addition, measurement of chamber oxygen saturations during right heart catheterization can be diagnostic for left to right shunts. Many persons live 10 or 15 years after diagnosis, but disability will slowly increase.