High 18F-FDG uptake in a systemic right ventricle after atrial switch

Area of Science:

• Cardiology
• Nuclear Medicine
• Congenital Heart Disease

Background:

• D-transposition of the great arteries (dtGA) is a complex congenital heart defect.
• Atrial switch operations, like the Senning procedure, reroute blood flow in dtGA patients.
• Long-term physiological adaptations post-surgery require ongoing investigation.

Observation:

• A 21-year-old patient with a history of Senning correction for dtGA underwent F-FDG PET/CT for oncological assessment.
• The scan incidentally revealed significant myocardial metabolic activity.
• Distinct patterns of Fluorodeoxyglucose (FDG) uptake were observed between the ventricles.

Findings:

• The morphological right ventricle, functioning as the systemic ventricle post-Senning, demonstrated intense FDG uptake.
• The morphological left ventricle, serving as the pulmonary ventricle, exhibited very faint FDG uptake.
• This differential uptake highlights metabolic adaptation to altered hemodynamics.

Implications:

• F-FDG PET/CT can visualize metabolic changes in ventricles after complex congenital heart surgery.
• Understanding these metabolic shifts is crucial for monitoring long-term cardiac health in operated dtGA patients.
• This case underscores the importance of evaluating ventricular function and metabolism in adults with repaired congenital heart disease.