The world's largest family with familial atrio-ventricular nodal reentry tachycardia.

We report a three-generation family coming from southeastern region of Poland (Podkarpackie voivodship) with 6 women having normal hearts and presenting with a history of paroxysmal tachycardia with onset of symptoms in the adulthood. Recordings of clinical SVT, dual AVN electrophysiology, induction of typical AVNRT and results of RFCA are available. The history of this family shows the significance of a careful and detailed collection of medical history, and point towards the importance of family screening in AVNRT patients.