First Degree Heart Block - Heart Blocks.

Description

• First Degree Heart Block will look like a typical sinus rhythm with one distinguishing feature.
• The P-R interval will be constant throughout the tracing and measure greater than 0.20 seconds.
• Rate, regularity, P wave morphology and QRS duration and morphology will be unaffected.
• NOTE: The rate will be that of the underlying rhythm. If the rate is “normal”, it will be 60 – 100 bpm. If it is bradycardia, the rate will be less than 60 bpm.
• First Degree Heart Block is the most common heart block.
• People are born with it every day. They will likely live a long and healthy life and die from some other malady.
• Patients who develop a heart block during an MI bear close observation. This must be reported to the licensed healthcare practitioner immediately.

Example

Notice the following: the only abnormality when analyzing this tracing is the abnormal duration of the P-R interval.

Practice Strip

Analyze this tracing using the five steps of rhythm analysis.

Show Answer

• Rhythm: Regular
• Rate: 68
• P Wave: Upright
• PR interval: 0.28 sec
• QRS: 0.08 sec
• Interpretation: First Degree Heart Block