Fig. 1

Electrocardiogram on admission to ICU. Regular positive P waves of 180–190 bpm and corresponding narrow QRS waves are seen in V1 and V2, although the P wave is masked by the T wave in most leads.
Electrocardiogram on admission to ICU. Regular positive P waves of 180–190 bpm and corresponding narrow QRS waves are seen in V1 and V2, although the P wave is masked by the T wave in most leads.