A 3 1/2 year old boy is presented with postaxial hexodactily in all extremities, a persisting large left vena cava superior (VCS) draining into the left part of a single atrium and a mild dextroversio cordis. All extra fingers and the lateral parts of the fused metatarsals were amputated. At age 10, the cardiovascular anomalies were surgically corrected successfully by separating the atrium with a pericardial patch and by draining the left VCS to the right atrium with a graft. The patient seems to represent a new syndrome, since the combination of postaxial hexodactily with single atrium had previously been observed by the author in another patient in 1970.