Lecompte manoeuvre		The pulmonary artery is brought anterior to the aorta during an arterial switch procedure in patients with d-transposition of the great arteries. see also Jatene procedure.
LEOPARD syndrome		This autosomal dominant condition includes Lentigines, ECG abnormalities, Ocular hypertelorism, Pulmonary stenosis, Abnormal genitalia, Retardation of growth, and Deafness. Rarely, cardiomyopathy or complex congenital heart disease may be present.
levocardia		Leftward oriented cardiac apex (normal). see cardiac position.
levoposition		Leftward shift of the heart. see cardiac position.
ligamentum arteriosum		A normal fibrous structure that is the residuum of the ductus arteriosus after its spontaneous closure.
long-QT syndrome		Abnormal prolongation of QT-duration with subsequent risk for torsade de pointes, syncope and sudden cardiac death. It may be congenital or acquired (medications such as antiarrhythmics, antihistamines, some antibiotics; electrolyte disturbances such as hypocalcemia, hypomagnesemia, hyopkalemia; hypothyroidism; and other factors.). QT-interval must be adjusted to heart rate.
looping		Bending of the primitive heart tube (normally to the right, dextro, d-) that determines the atrio-ventricular relationship.
d-loop		morphologic right ventricle lies to the right of the morphologic left ventricle (normal rightward bend).
l-loop		morphologic right ventricle lies to the left of the morphologic left ventricle (leftward bend).
Lutembacher syndrome		Atrial septal defect associated with mitral valve stenosis. The mitral valve stenosis is usually acquired (rheumatic).
LVOTO		Left ventricular outflow tract obstruction.