Three-Dimensional Imaging Defines Straddling Mitral Valve Anatomy to Allow Successful Biventricular Repair.

Area of Science:

• Pediatric Cardiology
• Congenital Heart Surgery
• Medical Imaging

Background:

• Straddling mitral valve (MV) repair can be complex, often requiring papillary muscle and chordae relocation, increasing surgical risks.
• Infantile congenital heart defects like D-transposition of the great arteries (dTGA) can present with complex valve anomalies.

Purpose of the Study:

• To describe a simplified surgical approach for biventricular repair of a straddling mitral valve in an infant with d-transposition of the great arteries.
• To highlight the utility of three-dimensional (3D) imaging in surgical planning for complex congenital heart defects.

Main Methods:

• A nine-month-old infant with d-transposition of the great arteries and a straddling mitral valve was evaluated.
• Three-dimensional imaging was utilized to precisely map the ventricular septum and ectopic papillary muscle position.
• A surgical strategy involving ventricular septal defect (VSD) patch closure and arterial switch operation (ASO) was performed.

Main Results:

• Three-dimensional imaging accurately identified ventricular septum malposition relative to the straddling mitral valve.
• A simplified repair strategy, closing the VSD rightward of the ectopic papillary muscle, was successfully implemented.
• The patient underwent successful biventricular repair concurrent with the arterial switch operation.

Conclusions:

• Three-dimensional imaging is invaluable for planning safe and effective biventricular repair of straddling mitral valves in infants.
• A simplified surgical approach, guided by 3D imaging, can avoid complex papillary muscle relocation, reducing operative risks.
• This case demonstrates a successful management strategy for a complex congenital heart defect involving a straddling mitral valve.