Straddling and displaced atrioventricular orifices and valves

Area of Science:

• Cardiology
• Anatomic Pathology
• Pediatric Cardiology

Background:

• Straddling and displaced atrioventricular (AV) valves are complex congenital heart anomalies.
• These conditions often occur with other cardiac malformations, impacting diagnosis and treatment.

Purpose of the Study:

• To anatomically classify and describe straddling and displaced AV valves.
• To delineate the specific features and associations of these AV valve anomalies.

Main Methods:

• Anatomic study of 96 human hearts.
• Detailed examination of atrioventricular valve morphology and spatial relationships.
• Classification based on the extent of valve involvement (annular, peripheral, complete).

Main Results:

• Defined three forms of straddling AV valves: complete, annular, and peripheral.
• Described displaced AV valves where the entire valve is in the contralateral ventricle.
• Identified common associations with conditions like complete transposition and double outlet ventricles.
• Noted specific associations, such as straddling mitral valve in Taussig-Bing heart and straddling tricuspid valve with AV canal defects.

Conclusions:

• Straddling and displaced AV valves represent distinct anatomical variations.
• Accurate differentiation from other conditions, such as criss-cross hearts, is crucial for diagnosis.
• Understanding these anomalies aids in the diagnosis and management of complex congenital heart disease.