A 33-year-old woman with previously repaired partial atrioventricular septal defect and mild unrepaired coarctation of the aorta was admitted to Royal Brompton & Harefield Hospitals Specialist Care with worsening heart failure symptoms following her second successful pregnancy.

Transthoracic echocardiography provided a diagnosis of a severely dilated left ventricle with ejection fraction of 43% (the percentage of blood leaving the heart each time it contracts). A left-ventricle ejection fraction of 55% or higher is considered normal. The echocardiography also showed a severely dilated left atrium, severe left atrioventricular valve (LAVV) regurgitation (a condition in which the valve does not close tightly, allowing blood to flow backwards in your heart) comprising of multiple jets and mildly increased diastolic gradients through the valve.

A 3D echocardiographic (3DE) rendering of LAVV from ventricular and atrial aspects demonstrated double-orifice valve with excessive bridging tissue. There was severe prolapse of the whole of anterior leaflet through the anterior orifice and bulky appearance of the posterior leaflet resulting in three jets of regurgitation.

Further investigation with cardiac magnetic resonance imaging confirmed 3DE findings showing double-orifice LAVV with severe regurgitation, severely dilated LV and LA. The patient underwent surgical replacement of LAVV with a 31-mm St. Jude Medical prosthesis.

Post-operative course was uneventful and follow-up echocardiography showed a well-seated prosthetic valve with mild transvalvular regurgitation and no LV outflow tract obstruction.

Double-orifice LAVV is a rare congenital diagnosis, which can result in both stenosis and regurgitation. 3DE allowed detailed morphological assessment of the LAVV and surrounding structures, visualization of the orifices and prolapsing leaflets, understanding the mechanism of regurgitation, and facilitated management strategy.

Abbreviations: Ao – aorta; IVS – interventricular septum; LA – left atrium; LAA – left atrial appendage; LAVV – left atrioventricular valve; LV – left ventricle; LVOT – left ventricular outflow tract; RV – right ventricle.