A 59-year-old man with history of hypertension and heavy smoking presented with recurrent dizziness, palpitation and chest pain during exertion. At admittance, an ECG recording showed rapidly conducting atrial fibrillation (mean heart rate 140 bpm) and otherwise normal findings. Blood pressure and a laboratory examination were normal. Within a few minutes after admission, atrial fibrillation spontaneously converted to sinus rhythm. To …