Atrial fibrillation ‘begets’ atrial fibrillation. In the control state a short burst of atrial pacing in this goat model induces a brief episode of rapid atrial fibrillation. Repeated re-induction of atrial fibrillation leads to progressive acceleration of the fibrillatory impulses and longer duration of the arrhythmia. After 2 weeks atrial fibrillation which is induced does not terminate spontaneously. Reproduced with permission from Wijffels MC, Kirchhof CJ, Dorland R, et al. Atrial fibrillation begets atrial fibrillation. A study in awake chronically instrumented goats. Circulation 1995; 92: 1954–68.