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Based on the provided ECG description (Atrial Fibrillation), which of the following statements is correct?

A) The P wave is variable, and there are no QRS complexes following the P waves, indicating irregular electrical activity in the atria and a narrow complex rhythm.

B) The P wave is absent, leading to an irregular QRS pattern, suggesting potential issues with atrial depolarization.

C) The PR interval is unable to be determined, indicating a potential conduction abnormality in the atria.

D) The rhythm is regular, and the heart rate is 90 beats per minute, suggesting a stable and normal heart rate despite the irregular rhythm.

1 Answer

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Final answer:

The correct ECG description for Atrial Fibrillation is that the P wave is absent, leading to an irregular QRS pattern, which suggests issues with atrial depolarization. This is because Atrial Fibrillation is characterized by a lack of visible P waves and an irregular ventricular response due to chaotic atrial activity.

Step-by-step explanation:

Based on the provided description of Atrial Fibrillation (A_F), the correct statement regarding the ECG changes is B) The P wave is absent, leading to an irregular QRS pattern, suggesting potential issues with atrial depolarization. In A_F, the electrical pattern is irregular prior to the QRS complex, and the frequency between the QRS complexes (heartbeats) is often irregular. This occurs because in A_F, the atria are not contracting in a regular, synchronized fashion as they would under normal conditions, which normal P waves would indicate. Instead, there is chaotic electrical activity in the atria, which eliminates the appearance of distinct P waves and leads to irregular conduction of impulses to the ventricles, reflected as an irregular QRS pattern.

It is important to recognize that atrial fibrillation is characterized by a lack of visible P waves and an irregularly irregular rhythm. The atria contract in a rapid and disorganized manner, which results in an irregular ventricular response. However, it doesn't necessarily imply a problem in the PR interval as in option C, nor does it mean there is a regular rhythm as suggested in option D. Option A is incorrect because it describes a scenario where the P waves are present but variable, and no QRS complexes follow them, which does not describe A_F.

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