Even though patients with pulmonary embolism usually present with respiratory distress and tachycardia, the patient presented with syncope only. Typical ECG changes associated with PE include right axis deviation, right bundle-branch block, S1Q3T3 pattern, arrhythmia, nonspecific ST-segment changes, QR pattern in lead V1, Brugada ECG pattern, and T-wave inversions in the precordial leads. However, his electrocardiogram showed QT-interval prolongation and simultaneous T-wave inversions in the inferior and anterior leads. This ECG pattern is crucial for diagnosing PE. The patient underwent computed tomography-pulmonary angiography, which revealed pulmonary embolism. At the same time, these ECG changes should be differentiated from those of long QT syndrome, myocardial ischemia, Takotsubo cardiomyopathy, post-pacing T-wave memory, hypertrophic cardiomyopathy, and subarachnoid hemorrhage.