Tricuspid Valve Straddling: An Uncommon Cause of Left Ventricular Outflow Tract Obstruction in Transposition of Great Artery with Ventricular Septal Defect

Transposition of great arteries (TGA) can be associated with left ventricle outflow tract (LVOT) obstruction. In the presence of ventricular septal defect (VSD), septal leaflet of tricuspid valve may prolapse through perimembranous VSD or rarely tricuspid valve tissue may override to produce LVOT obstruction. Occasionally, this may be mistaken for vegetation due to associated pulmonary valve endocarditis. We report a case of d-TGA with presumptive pulmonary valve endocarditis and LVOT obstruction that was found to be due to tricuspid valve straddling on transesophageal echocardiography, resulting in change in the surgical plan and thus avoiding catastrophe.