Rosh Emergency Medicine Practice Test

For a COPD patient with a history of tachycardia, what might be expected on their electrocardiogram?

1. Narrow complex tachycardia

2. Wide complex tachycardia

3. Sinus bradycardia

4. Isolated PVCs

The correct answer is: Narrow complex tachycardia

In a COPD patient with a history of tachycardia, the most likely finding on the electrocardiogram is narrow complex tachycardia. The rationale for this is primarily rooted in the common underlying mechanisms of tachycardia in patients with COPD, particularly when considering factors such as hypoxia, hypercapnia, and heightened sympathetic tone, which can lead to sinus tachycardia. Narrow complex tachycardia often signifies a tachyarrhythmia that arises from the atria or the AV node, such as atrial fibrillation or atrial flutter, which may occur in patients with respiratory disorders like COPD, especially during exacerbations or when there is significant fluid overload. This is pertinent as the heart's demand may increase due to inadequate oxygenation, which is common in these patients. On the other hand, wide complex tachycardia tends to suggest a more serious issue, typically implying a ventricular origin. This may include conditions such as ventricular tachycardia or bundle branch block, which are less common in the setting of COPD compared to narrow complex tachycardia related to atrial activity. Sinus bradycardia is generally not associated with tachycardic presentations, particularly in COPD