Holt-Oram syndrome, also known as heart-hand syndrome or cardiac-limb syndrome, refers to a rare genetic condition involving abnormalities of the heart and upper limbs. Those affected have malformations or abnormalities of the bones in the thumbs, wrists, and arms, but lower extremities are not affected. Bones may be missing, extra, underdeveloped, or malformed. There may also be problems with the shoulder blades and collarbones. In some children the thumb is absent (National Organization for Rare Disorders, Inc. [NORD], 2000). The severity varies greatly with the individual and may be as slight as limited range of motion or as great as complete absence of upper limbs.
An inherited disorder, transmitted as an autosomal trait, that is marked by anomalies of the upper limbs and heart. Clinical manifestations vary from minimal radiographic changes to overt structural changes in the hands and arms and single or multiple atrial and ventricular defects that may be life-threatening.
This genetic disorder is characterized by an atrial septal defect, which refers to a hole in the wall that separates the upper chambers of the heart. Along with this condition, individuals with the disorder also exhibit several abnormalities in the upper limbs, especially affecting the hands and forearms.