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Updated: Aug 29, 2026

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Published on: June 29, 2022
Atrial escape-capture bigeminy in dominant atrial rhythm with 2:1 exit block
Takakazu Katoh1, Shinji Kinoshita, Ryuzaburou Yasuda
1Katoh Cardiovascular Clinic, Ohtsu, Japan.
Abstract:
A 27-year-old woman with atrial bigeminy is reported in whom long PP intervals alternate with short PP intervals. All P waves are negative in lead II and all PR intervals measure 0.12 s. In the 12-lead electrocardiogram, however, these P waves were definitely different in configuration from each other, and were divided into two groups. Namely, these negative P waves are divided into those of dominant atrial rhythm J1 with 2:1 exit block, and those of atrial escape J2. Long J1-J2 intervals alternate with short J2-J1 intervals. These electrocardiographic findings show the presence of atrial escape-capture bigeminy. Such atrial escape-capture bigeminy in dominant atrial rhythm with 2:1 exit block has never been reported before.
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