Figure 2. The three categories of causative disorders.

All potential causes of transient ischemic attack can be allocated within one of three categorical concentric circles, and the areas of intersection constitute those patients with concurrent conditions (i.e., “double jeopardy”). Each of these three domains can be evaluated by means of different tests, listed in the figure. See text for further description. CTA, computed tomography angiography; EKG, electrocardiogram; MRA, magnetic resonance angiography; MRI, magnetic resonance imaging; NVU, neurovascular ultrasound; TEE, transesophageal echocardiogram; TTE, transthoracic echocardiogram.