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Nocturnal Second-Degree Type I AV Block: A Benign Manifestation of Vagal Tone in Sleep Jun 13, 2025

Second-degree type I AV block, also known as Mobitz I or Wenckebach, is typically characterized by a progressive prolongation of the PR interval followed by a dropped beat. While often evaluated for underlying conduction disease, it is not always pathological—especially when it occurs exclusively du...

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Inferoposterior STEMIs and Complete Heart Block: A Look at AV Node Anatomy and RCA Supply Jun 04, 2025

Complete heart block—or third-degree AV block—is a feared complication of ST segment elevation myocardial infarction (STEMI), particularly when the infarct involves the inferior or posterior walls of the heart. This pattern is not random. It’s grounded in the anatomical relationship between the righ...

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