Spontaneous regression of severe aortic coarctation in trisomy 18.

Spontaneous regression of severe aortic coarctation with ductus dependency has not been reported. We experienced a case of trisomy 18 with spontaneous regression of severe aortic coarctation complicated by ventricular septal defect and patent ductus arteriosus. The aortic isthmus diameter was 1.2 mm at birth. After 5 months, it increased to 4.5 mm, and the shape of the isthmus was fully normalised.