Key words double wave reentry atrial tachycardia 3D mapping ablation electroanatomical mapping reentry Introduction Double wave reentry (DWR) is an uncommon reentry mechanism where two independant waves are circulating in the same circuit at the same time, doubling the rate of activation. Such mechanism had been postulated from experimental findings, but clinical demonstrations remained limited. We report the first 3D documentation of clinical DWR in a patient with atrial tachycardia.