Shone syndrome

Shone syndrome, also known as Shone complex, is a rare syndrome characterized by left-sided, obstructive congenital heart defects.

Epidemiology

Shone syndrome is thought to be very rare, accounting for less than 1% of all congenital heart disease ¹.

Clinical presentation

Patients, usually neonates and infants, present with signs and symptoms of congestive cardiac failure ^1-3. On clinical examination, patients may have murmurs heard over both the aortic and mitral areas during precordial auscultation ⁴.

Pathology

The complete Shone syndrome consists of four cardinal left-sided cardiac defects ^1-3:  

• supravalvular mitral membrane
• subvalvular aortic stenosis (membranous or muscular)
• parachute mitral valve
• coarctation of the aorta

Although four features were originally described, it is more common for patients to have incomplete Shone syndrome with only some of the obstructive lesions ³. 

Radiographic features

Case studies have utilized both echocardiography and CT in order to identify each of the four obstructive cardiac defects in Shone syndrome ^1,4. 

See individual articles for a detailed description of each defect.

Treatment and prognosis

Surgical intervention is required in all cases. Generally, patients will need multiple surgeries at initial presentation, as well as repeated surgeries throughout their life ^2,3.

History and etymology

The syndrome is named after John D Shone (1924-2002), an English pediatric cardiologist, who described the constellation of features in his 1963 seminal paper ⁵.