Unmasking Partial Shone Complex: A Late Diagnosis with Rare Associations

Shone complex (SC), also known as Shone syndrome, is a rare congenital heart disease first described in 1963 that involves the coexistence of 4 left ventricular (LV) inflow and outflow obstructions including a parachute mitral valve (PMV), supravalvular mitral ring, subvalvular aortic stenosis (AS), and aortic coarctation. The incomplete form, or partial SC, involves only 2 or 3 of these anomalies.1 Inflow obstructions include PMV, supravalvular mitral ring (supravalvular ring of the left atrium), or congenital mitral stenosis (MS).