A 54-year-old man was admitted to hospital with an episode of chest pain lasting one hour. The ECG showed Q waves together with E-ST in inferior leads and D-ST in leads I, aVL and V4-V5. In right precordial leads a marked J-wave followed by a convex and descending D-ST ending in a negative T-wave could also be observed. With the diagnosis of inferior AMI he received fibrinolytic treatment with tenecteplase. One hour later the ECG, recorded with mild precordial pain, revealed no inferior ST-segment elevation, a negative T-wave in aVL and a J-point elevation > 0.2 mV with descending ST-segment and negative T-wave in leads V1-V2, suggesting an electrocardiographic pattern of SB. Five hours later the ECG showed a prominent J-wave with convex and saddle E-ST in leads V1 and V2, respectively. There was also a J-point elevation associated with a positive E-ST and T-wave in leads V3-V4. Three days after admission the ECG revealed an inferior qR pattern along with a negative T wave in leads III and aVF, a manifest J wave in leads V1-V2, a concave E-ST with positive T wave in leads V2-V3, and no S wave in the left leads. He had no ventricular arrhythmias during hospitalisation. The peak values of creatine kinase and troponin I were 1,398 U/l and 23.2 ng/ml, respectively. Coronary arteriography revealed a proximal (95%) stenosis of the right coronary artery and a stent was placed. After discharge, 6 months later he underwent a flecainide challenge test (2 mg/kg intravenously over 10 minutes) which was negative for a diagnosis of SB.