Mae'r Ysgrifennydd Iechyd, Vaughan Gething wedi cymeradwyo'r cam hwn wedi i adolygiad ganfod nad yw mwyafrif y profion sydd eu hangen ar gleifion cardiaidd yn gorfod cadw at y targed o wyth wythnos.
Health Secretary, Vaughan Gething, has approved the move after a review found the majority of tests cardiac patients need are currently not subjected to the eight week target.