Lumpers or splitters

For more than 25 years, neurologists and cardiologists have debated the role of transesophageal echocardiography (TEE) in the evaluation of patients with acute ischemic stroke (AIS) of unknown cause. Approximately 1 in 4 stroke patients do not have a specific cause elucidated by routine inpatient evaluations, and mounting data suggest that many of these patients have occult cardiac sources of embolism (CSE). Recently, the new classification of embolic stroke of undetermined source (ESUS) has been proposed to define the subset of patients in whom there is suspicion, but not proof of, a CSE.1 TEE, however, is not required for a diagnosis of ESUS. Proponents of routine use of TEE in patients with cryptogenic stroke or ESUS note its superiority to transthoracic echocardiography in detection of CSE2 and the higher morbidity and mortality associated with strokes of cardiac cause.3 In contrast, detractors point to increased cost and risk with a relatively low yield of management-changing findings.