What is the most common ECG abnormality in patients with a pulmonary embolism?

What is the most common ECG abnormality in patients with a pulmonary embolism?

• A. Atrial fibrillation
• B. Sinus tachycardia
• C. Ventricular ectopy
• D. Sinus bradycardia

Answer: (B)

Sinus tachycardia is the most common ECG finding in pulmonary embolism. When a clot blocks part of the pulmonary circulation, the heart faces sudden increased afterload on the right side and potential hypoxemia. The body's response is to speed up the heart to maintain cardiac output and oxygen delivery, so the ECG most often shows a normal rhythm with an elevated rate. This non-specific change is more frequent than other rhythm disturbances. Atrial fibrillation, ventricular ectopy, or sinus bradycardia can occur, but they are less common in the PE setting. Classic patterns like S1Q3T3 can appear but are far less common than just a fast heart rate.

Sinus tachycardia is the most common ECG finding in pulmonary embolism. When a clot blocks part of the pulmonary circulation, the heart faces sudden increased afterload on the right side and potential hypoxemia. The body's response is to speed up the heart to maintain cardiac output and oxygen delivery, so the ECG most often shows a normal rhythm with an elevated rate. This non-specific change is more frequent than other rhythm disturbances. Atrial fibrillation, ventricular ectopy, or sinus bradycardia can occur, but they are less common in the PE setting. Classic patterns like S1Q3T3 can appear but are far less common than just a fast heart rate.