The differential diagnosis included acute coronary syndrome and acute pericarditis. The patient presented with anterior chest pain and dyspnea, and ECG showed ST elevation in V3 through V6. We present a case of PE that went unrecognized in the emergency department (ED). Elevation of ST segment is a rare ECG manifestation with PE. Possible ECG changes with acute PE include S(1)Q(3)T(3) pattern, atrial tachyarrhythmias, incomplete right bundle-branch block, or negative T wave over right and midprecordial leads. Although acute pulmonary embolism (PE) may give rise to certain electrocardiographic (ECG) changes, most of these changes have low sensitivity and specificity and are of limited value alone in the diagnosis.
