Billowing mitral valve syndrome in association with absent left pericardium: a case report.

A patient with congenital complete absence of the left pericardium had a late systolic murmur and an intermittent non-ejection systolic click. A post-exercise ECG showed ST-segment depression and T-wave inversion, compatible with that described in the billowing mitral leaflet syndrome. Left ventricular cine-angiography confirmed prolapse of the mitral valve. It is suggested that an associated billowing mitral leaflet syndrome may be responsible for chest pain, variable auscultatory features and abnormal ECGs in some patients with absent left pericardium.