Bayes Syndrome – Cardiology MCQ – Answer

Bayes Syndrome – Cardiology MCQ – Answer

Bayes Syndrome – Correct Answer: 

  1. Third degree interatrial block with paroxysmal supraventricular arrhythmias

Various degrees of interatrial blocks are identified as follows:

  1. First degree interatrial block: P wave duration more than 120 ms
  2. Third degree interatrial block: Longer P wave duration with biphasic P waves in inferior leads
  3. Second degree interatrial block: These abnormalities are seen transiently in same ECG (atrial aberrancy)

It may be noted that these abnormalities may occur with or without associated atrial enlargement detectable by imaging modalities.

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  1. Bayés de Luna A, Platonov P, Cosio FG, Cygankiewicz I, Pastore C, Baranowski R, Bayés-Genis A, Guindo J, Viñolas X, Garcia-Niebla J, Barbosa R, Stern S, Spodick D. Interatrial blocks. A separate entity from left atrial enlargement: a consensus report. J Electrocardiol. 2012 Sep;45(5):445-51.
  2. Adrian Baranchuk, Pelayo Torner, Antoni Bayés de Luna. Bayés Syndrome – What Is It? Circulation. 2018;137:200-202.