Normal Sinus Rhythm (NSR) with First-Degree Atrioventricular Block (1° AVB) is a cardiac rhythm where the basic underlying rhythm is normal, originating from the sinoatrial (SA) node, but there is a delayed conduction of electrical impulses from the atria to the ventricles.
Heart Rate: 60 to 100 beats per minute
Rhythm: Regular
P wave: Present before each QRS complex
PR Interval: Prolonged
QRS: 0.06-0.11 seconds
NSR with First-Degree Atrioventricular Block is diagnosed through clinical assessment and electrocardiogram (ECG) findings, which reveal a prolonged PR interval.
The management of 1° AVB depends on the patient's clinical condition and the degree of block. Options include: Identify and Address Underlying Causes: If an underlying cause is identified (e.g., medications, electrolyte imbalances), it should be addressed or eliminated. Medications: In rare cases where first-degree AVB is symptomatic and related to a medication, adjusting or discontinuing the medication may resolve the block.