Which EKG pattern is characteristic of PE and indicates right heart strain?

Which EKG pattern is characteristic of PE and indicates right heart strain?

• A. S1Q3T3 pattern indicating right heart strain
• B. Left axis deviation
• C. Peaked T waves in V1-V3
• D. Delta wave pattern

Answer: (A)

Right heart strain from an acute pulmonary embolism can shift the heart’s electrical vector and create a distinctive ECG pattern. The S1Q3T3 pattern—an S wave in the first lead and a Q wave with T-wave inversion in the third lead—is classically linked to this acute right‑sided strain. It flags that the right ventricle is under sudden load from a PE, which helps support the diagnosis when the clinical picture fits. It’s important to know it’s not universally present, but when you see S1Q3T3, it strongly points toward acute RV involvement from PE. Other patterns listed aren’t associated with PE-related right heart strain: left axis deviation reflects different axis shifts or LV issues, peaked T waves in V1–V3 suggest other processes (like hyperkalemia or different etiologies), and a delta wave indicates WPW pre-excitation, not PE.

Right heart strain from an acute pulmonary embolism can shift the heart’s electrical vector and create a distinctive ECG pattern. The S1Q3T3 pattern—an S wave in the first lead and a Q wave with T-wave inversion in the third lead—is classically linked to this acute right‑sided strain. It flags that the right ventricle is under sudden load from a PE, which helps support the diagnosis when the clinical picture fits. It’s important to know it’s not universally present, but when you see S1Q3T3, it strongly points toward acute RV involvement from PE. Other patterns listed aren’t associated with PE-related right heart strain: left axis deviation reflects different axis shifts or LV issues, peaked T waves in V1–V3 suggest other processes (like hyperkalemia or different etiologies), and a delta wave indicates WPW pre-excitation, not PE.