Some friends ask, sometimes we go to the hospital for physical examination, or do ECG in the hospital when we are not feeling well, the doctor will tell you that the ECG is I degree AVB (first degree AVB), at this time we are confused, “What should I do?” In order to solve this confusion, I will give you a brief introduction of first degree AVB. I. What is degree I AVB? AV block is an abnormality in the conduction of impulses between the atria and the ventricles. Atrioventricular block can be a total block, a partial block, or a conduction delay. A degree I AV block occurs when conduction of the impulse from the atrium through the AV node is finalized and conduction is only prolonged compared to normal conduction time. It is like people standing in line to pass through a gate, but each person hesitates as they pass through the gate. How does a degree I AV block occur? A degree I AV block can occur in normal healthy people, or in people with myocardial ischemia, myocardial infarction, myocarditis, or degenerative heart disease. This condition can also be caused by medications such as digitalis, calcium antagonists, and beta-blockers. Atrioventricular block of degree I can be transient, especially when coming from medications or the early ischemic phase of myocardial infarction. degree I AV block is the least dangerous type of AV block and suggests some kind of problem with the conduction system. Because degree I can progress to a higher degree of AV block, it must be monitored for changes. degree I AV block is associated with corresponding electrocardiographic changes, with delayed PR intervals of greater than 0.20 seconds on the ECG indicating atrial-ventricular conduction. What are the signs and symptoms of a degree I AV block? There can be no signs of a degree I AV block because the cardiac output is not significantly affected by it. If the PR interval is significantly prolonged, the physician will notice a significant change during cardiac auscultation of the heart sounds S1 and S2. IV. How to intervene in a degree I AV block? Usually only the underlying cause of the presence is addressed, and not the degree I block itself. For example, if a medication is causing it, it may need to be reduced or discontinued. Close monitoring of electrocardiographic changes is also useful to observe the progression of degree I block. In a patient with a degree I AV block, it is important to evaluate his correctable underlying etiology, such as medications or myocardial ischemia. Patients taking digitalis, calcium antagonists, and beta-blockers should be particularly alert to the development of conduction block.