Massive ST-Segment Elevation in Acute Pulmonary Embolism

A 71-year-old man presented to the emergency department with dyspnea. His blood pressure was 151/116 mmHg, and 82% oxygen saturation on room air. Intubation was performed for respiratory failure. ECG showed atrial fibrillation with tachycardia and ST-segment depression in leads V1–6 (Figure A). Contrast-enhanced computed tomography demonstrated multiple pulmonary emboli (Figure B), resulting in a diagnosis of acute pulmonary embolism (APE). His blood pressure gradually decreased, and ECG showed massive ST-segment elevation in leads aVR, V1–2 and V3R–6R and ST-segment depression in leads I, II, aVL and V3–6 (Figure C). Echocardiography showed dilated right ventricular (RV) with RV/left ventricular (LV) ratio of 1.67 and compression of the LV (Supplementary Movies 1,2), which was not observed on admission. The patient received a bolus injection of 5,000 units and subsequent continuous infusion of intravenous heparin. ST-segment elevation was resolved on ECG 30 min later (Figure D). The RV/LV ratio decreased to 1.08, and compression of the LV disappeared on echocardiography.

Figure.

(A) ECG showing atrial fibrillation with tachycardia and ST-segment depression in leads V1–6. (B) Contrast-enhanced computed tomography showing multiple pulmonary emboli. (C) ECG showing massive ST-segment elevation in leads aVR, V1–2 and V3R–6R, and ST-segment depression in leads I, II, aVL and V3–6. (D) Resolution of ST-segment elevation on ECG at 30 min after treatment.

ST-segment elevation in APE is uncommon (3–18%), and its underlying mechanism is uncertain, but may involve transmural RV ischemia due to RV pressure overload, hypoxemia and hypotension.¹ In this case, ECG during hemodynamic instability showed ST-segment elevation in lead aVR and the right precordial leads, facing the basal septum and anterior region of the RV, respectively. Notably, ST-segment elevation in this case was massive but resolved in a short time. The development of acute cor pulmonale due to rapid RV dilation may cause dynamic ECG changes in APE.

Disclosure

M.K. and K.K. are members of Circulation Journal’s Editorial Team.

Supplementary Files

Supplementary Movie 1. Parasternal long axis view of echocardiography at the time of ST-segment elevation.

Supplementary Movie 2. Parasternal short axis view of echocardiography at the time of ST-segment elevation.

Please find supplementary file(s);

https://doi.org/10.1253/circj.CJ-22-0417

Reference

• 1.   Zhang J, Liu G, Wang S, Du W, Lv P, Guo H, et al. The electrocardiographic characteristics of an acute embolism in the pulmonary trunk and the main pulmonary arteries. Am J Emerg Med 2016; 34: 212–217.