First Degree Heart Block | Reference Guide.

EKG Features

Rate: The underlying rate
Rhythm: Regular
P Wave: Normal
PR Interval: Prolonged (>0.20 sec)
QRS: Normal (0.06-0.10 sec)
Will look like a typical sinus rhythm. The P-R interval will be constant throughout the tracing and measure greater than 0.20 seconds.
A first degree Heart block occurs when electrical impulses moving through the Atrioventricular (AV) node are delayed (but not blocked). First degree indicates slowed conduction without missed beats.
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