Anterolateral muscle bundle of the left ventricle in atrioventricular septal defect: left ventricular outflow tract and subaortic stenosis.

The anatomy of the left ventricular outflow tract (LVOT) in 77 hearts with atrioventricular septal defect (AVSD), 36 with a separate A V orifice and 41 with a common A V-orifice, were investigated. In all specimens, an anterolateral muscle bundle of the left ventricle was identified between the superior bridging leaflet and the left coronary aortic cusp. It displaced the attachment of the superior bridging leaflet, resulting in its clockwise rotation.

Single papillary muscle ("parachute valve") and double-orifice left ventricle in atrioventricular septal defect convergence of chordal attachment: surgical anatomy and results of surgery.

A review of 59 anatomical specimens and of the findings in 65 surgically repaired patients with atrioventricular septal defect (AVSD), revealed four patients with a single papillary muscle and 11 with a double-orifice left ventricle. A single papillary muscle of the left ventricle occurred in 1.7% (1 of 59) of the anatomical specimens, and 6% (4 of 65) of the surgical cases.

Two-dimensional echocardiography in atrioventricular canal malformation: a diagnostic approach.

Two-dimensional echocardiographic studies were performed in 20 children with various forms of atrio-ventricular canal malformation. Both sagittal and transverse cross-sections were evaluated. The most typical finding in all patients was the visualization of the cleft anterior mitral leaflet (AML) represented by a diastolic break of AML echoes in the sagittal cross-section.