ST-elevation and complete heart block: a rare presentation of pulmonary embolism

Pulmonary embolism can present with non-specific symptoms that overlap with acute coronary syndrome, such as chest pain, shortness of breath, and palpitations. Common electrocardiogram findings include sinus tachycardia and right bundle branch block; ST-segment elevations and complete heart block are extremely rare. We report a case of a 77-year-old man who initially presented with electrocardiogram findings of transient complete heart block and ST-segment elevation, which raised concern for acute coronary syndrome. Left heart catheterization was performed and did not reveal significant obstructive disease. Computed tomography pulmonary angiography with saddle pulmonary embolism suggested that thromboembolic disease was the main cause of the electrocardiogram changes. Clinicians should maintain a high index of suspicion for pulmonary embolism in patients presenting with abnormal electrocardiogram results and any underlying risk factors so as not to miss a life-threatening diagnosis.