Fig. 6.
Atrial alternans precedes initiation of atrial fibrillation.
Rate dependence of AP alternans in a 61-year-old male patient with paroxysmal atrial fibrillation. (A) No significant atrial AP alternans is observed at baseline pacing with cycle length (CL) of 500 ms. (B) At CL 300 ms, APD alternans is observed. (C) APD alternans were detectable and preceded AF initiation while pacing at CL 280 ms. V1, first ECG precordial lead; CSmid, middle coronary sinus; MAP, monophasic action potential.
Figure is modified with permission from [98].