Reversible Left Ventricular Hypertrabeculation and Hypermetabolism Following Bentall Procedure

Left ventricular hypertrabeculation may develop secondary to hemodynamic stress rather than represent primary cardiomyopathy. Its metabolic profile remains incompletely understood.

A 43-year-old woman presented with heart failure secondary to severe aortic regurgitation from aortic root dilatation. Imaging demonstrated left ventricular dilation, reduced ejection fraction (39.0%), and prominent hypertrabeculation. 18F-fluorodeoxyglucose (FDG)-positron emission tomography/computed tomography, following a high-fat, low-carbohydrate diet with 18-hour fasting, showed increased myocardial uptake (SUVmax 4.20). She underwent a Bentall procedure with coronary bypass grafting. Histopathology revealed cystic medial degeneration and mild interstitial fibrosis. During 4-year follow-up, ventricular dimensions decreased (59/48-43/32 mm), ejection fraction improved to 52.8%, and trabeculation regressed. Repeat FDG positron emission tomography/computed tomography demonstrated resolution of uptake (SUVmax 1.81).

Parallel regression of trabeculation and FDG uptake supports adaptive remodeling rather than intrinsic cardiomyopathy, although geometric unloading may contribute.

Correction of volume overload may normalize ventricular structure and metabolism.