A patient who has been diagnosed with myocardial infarction is getting an ECG. The ECG trace shows a series of nonconducted P waves followed by a P wave that is conducted to the ventricles. The ratio of nonconducted to conducted P waves is fixed at 4:1. What plan for treatment should this patient receive?
1) Rapid defibrillation
2) Atropine
3) Cardioversion
4) Pacemaker
A)1, 2, and 3 only
B)2 and 4 only
C)3 only
D)1, 2, 3, and 4

Question

Quizplus · Accepted Answer

The ECG findings described are indicative of a third-degree (complete) atrioventricular (AV) block, characterized by a fixed ratio of nonconducted to conducted P waves (in this case, 4:1). Atropine can be used to increase heart rate by blocking the action of the vagus nerve on the heart, potentially improving conduction temporarily. A pacemaker is often the definitive treatment for third-degree AV block, as it can provide reliable pacing to overcome the heart's intrinsic conduction system's failure. Rapid defibrillation and cardioversion are not appropriate treatments for AV block, as they are used for life-threatening arrhythmias like ventricular fibrillation or unstable tachyarrhythmias, not for conduction block issues.

A Patient Who Has Been Diagnosed with Myocardial Infarction Is