Beckman K, Ta-Lin H, Krafchek J, Wyndham C R
Pacing Clin Electrophysiol. 1986 Nov;9(6):826-35. doi: 10.1111/j.1540-8159.1986.tb06632.x.
Classic and concealed entrainment was demonstrated in a patient with spontaneous typical atrial flutter and pacing-induced atypical atrial flutter. The form of entrainment manifested depended on the site of pacing and the direction of tachycardia as determined by endocardial mapping.