Acute pulmonary embolism (PE)  is a common condition that can be both severe and difficult to diagnose. Half of all acute PE cases are diagnosed in the emergency department, and acute PE follows acute coronary syndrome as the second most common cause of sudden unexpected death in outpatients. Also, right ventricular dysfunction is a consequence of massive/submassive acute pulmonary embolism and correlates with a poor prognosis and high mortality rate. Although an ECG lacks both sensitivity and specificity for acute PE, there are some clues that can help in determining the size of an acute PE. What are some of the common ECG changes seen with massive acute PE? 1 ECG Changes Massive PE (%) Non-Massive PE (%) Anterior Ischemic Pattern 85 19 S1Q3T3 54 54 Sinus Tachycardia 36 0 Low Voltage 36 36 RBBB 22 24 Pulmonary P Waves 7 0 Study methodology: 80 patients enrolled, prospective study Conclusions: Anterior ischemic pattern (inverted T waves) on ECG was the most frequently observed ECG abnormality in patients with massive acute PE. Had the best sensitivity (85%), specificity (81%), PPV (93%), and NPV (65%) for massive acute PE Correlated highly with a Miller index of >50% (90%) and mean pulmonary artery pressure (PAP) >30 mmHg (81%) What are some of the common ECG changes seen with right ventricular dysfunction due to acute PE? 2–4 ECG Changes RV Dysfunction (%) Without RV Dysfunction (%) T-Wave Inversion in Leads V1 – V3 75 5 – 12 RBBB 30 – 46.4 3 – 17 Qr in Lead V1 31 3 S1Q3T3 25 – 35 5.5 – 10 Normal ECG 8 49 Study methodology: 204 patients enrolled with acute PE Conclusions: T-wave inversion in leads V1 – V3 was the most … Continue reading Acute Pulmonary Embolism: Size does matter and ECG can give us clues