What is the most likely etiology of a Transient Ischemic Attack?

Transient Ischemic Attacks (TIAs) are characterized by temporary episodes of neurological dysfunction resulting from an interruption in the blood flow to the brain. The primary etiology of a TIA is embolism, which refers to the obstruction of blood vessels by an embolus—a particle or debris that travels from another part of the body. This may come from a thrombus (a blood clot) that forms elsewhere, often in the heart or major arteries, and then travels to cerebral arteries, causing temporary ischemia.

During a TIA, the involved area of the brain does not receive adequate blood supply for only a short duration, and symptoms typically resolve quickly, usually within an hour. This scenario highlights the role of embolism in causing sudden and reversible disruptions in cerebral blood flow.

Other causes like thrombosis, which involves a clot forming at the site of a narrowed artery, may also lead to TIAs, but embolic events are the most common etiology, especially considering that TIAs are often linked with conditions such as atrial fibrillation that predispose individuals to embolic strokes. Thus, understanding that embolism is the predominant cause of TIAs helps in recognizing the underlying mechanisms of these neurological events and their potential relationship to more severe cerebrovascular