TIA is a neurologic emergency
The initial evaluation of suspected TIA and minor ischemic stroke requires urgent evaluation
What is Transient ischemic attack
Transient ischemic attack is transient episode of neurologic dysfunction caused by focal brain, spinal cord, or retinal ischemia, without acute infarction. The end point is biological (tissue injury) rather than arbitrary (24 hours) and requires use of neurodiagnostic tests to identify brain injury and its cause.
Vice President CMAAO and President HCFI Padma Shri Awardee Dr KK Aggarwal said,
“The classic old definition was sudden onset of a focal neurologic symptom and/or sign lasting less than 24 hours, caused by a transient decrease in blood supply. This classic definition is inadequate because even relatively brief ischemia can cause permanent brain injury.”
Types of TIA
According to Dr KK Aggarwal
Discrete, usually single, more prolonged (hours) episodes of focal neurologic symptoms. The embolus may arise from a pathologic process in an artery, usually extracranial, or from the heart (AF or LV thrombus) or aorta.
Lacunar or penetrating or small vessel:
Induced by stenosis of one of the intracerebral penetrating vessels arising from the middle cerebral artery stem, the basilar artery, or the vertebral artery. They are caused either by atherothrombotic obstructive lesions at the origin of the penetrating vessel or by lipohyalinosis distally within the penetrating vessel.
Large artery low-flow TIAs: are often associated with a tightly stenotic atherosclerotic lesions of the internal carotid artery origin, middle cerebral artery stem, or junction of the vertebral and basilar artery. Low-flow TIAs usually are often recurrent.
Several pathologic processes can cause low-flow TIAs or embolic TIAs that can produce sudden devastating stroke if not recognized and treated
Atherothrombotic lesions of the internal carotid artery that are narrowed more than 50 percent
Intracranial atherothrombotic disease that produces low-flow or embolic TIA
Emboli to the top of the basilar artery or the middle cerebral artery stem
Arterial dissection of the internal carotid artery or the vertebral artery
Therefore, the initial evaluation of suspected TIA and minor ischemic stroke requires urgent evaluation (uptodate)