heart-hand syndrome type 3 (Monarch Disease Ontology identifier MONDO_0007702) is a very rare heart-hand syndrome, described in three members of a Spanish family to date, which is characterized by a cardiac conduction defect (sick sinus, bundle-branch block) and brachydactyly, resembling brachydactyly type C of the hands, affecting principally the middle phalanges in conjunction with an extra ossicle on the proximal phalanx of both index fingers. Feet abnormalities are more subtle. Also known as: Cardiomelic syndrome type 3, atriodigital dysplasia type 3, heart-hand syndrome, Spanish type, heart-limb syndrome type 3.