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One Quick Question: What are the Second-Degree Heart Block Criteria? – Video
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Video at a Glance
Second-degree heart block Type I (Wenckebach) is characterized by:
- Regularity: R to R irregular with grouped beats
- Rate: Usually slower than normal
- P Wave: P waves are uniform but not always followed by QRS
- PR Interval: Becomes progressively longer until a P wave is blocked and the QRS is dropped
- QRS Complex: < 0.12 seconds
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