Pulmonary Embolism Diagnosed From Right Heart Changes Seen After Exercise Stress Echocardiography

A 47-year-old black woman with no prior medical problems presented to the emergency department after a syncopal event associated with palpitations while walking. The patient noticed new onset of palpitations while walking that lasted about an hour. She subsequently had a syncopal episode. She denied dizziness, lightheadedness, dehydration, or seizure-like activity. Medications included antihistamines and oral contraceptives. On admission she was afebrile, heart rate 84 bpm, blood pressure 121/73 mm Hg, respiratory rate 18 breaths per minute, and her oxygen saturation was 97% on room air. The physical examination was normal except for a small (1 cm) head laceration.A noncontrast computed tomography of the head was negative for any acute intracranial findings. The chest radiograph showed no acute cardiopulmonary disease. The electrocardiogram showed normal sinus rhythm at a ventricular rate of 69 bpm, no evidence of ST segment changes, and an isolated T wave inversion in V2 (Figure 1).Figure 1. Admission 12-lead ECG showing normal sinus rhythm and no suspicious findings.She was admitted with high suspicion for cardiac syncope given her symptoms of palpitations before the event. Myocardial infarction was ruled out. A pro-B-type natriuretic peptide was normal and thyroid-stimulating hormone test was normal. A D-dimer level was not checked. Telemetry was only significant for episodes of sinus tachycardia. A resting transthoracic echocardiogram was technically difficult but showed normal left ventricular (LV) size and function, ejection fraction 50%, and grossly normal right ventricular (RV) size and function (Figure 2; Movies I and II in the Data Supplement). There was not enough tricuspid regurgitation on the resting …