Pulmonary embolism in a patient with "isolated syncope", a diagnostic challenge.

Syncope is a recognized presenting symptom in patients with pulmonary embolism (PE), and is more common in older patients and following a large embolus. Isolated syncope, in the absence of dyspnea or tachycardia, is uncommon in this setting, and may be misdiagnosed as cardiac in origin, leading to a delay in appropriate treatment. We present a case which illustrates the importance of consideration of pulmonary embolism in the differential diagnosis of patients presenting with syncope, and the value of echocardiography in its diagnosis.