Long Summary
Every two seconds, someone globally experiences a stroke, highlighting its prevalence and impact as a major health concern. Strokes occur when oxygen supply to brain cells is interrupted, often leading to death or significant disability. Despite making up only 2% of body mass, the brain consumes over 20% of the body's oxygen, carried via arteries such as the carotid and vertebral arteries which branch into smaller vessels nourishing neurons. When blood flow is blocked, brain cells begin to die quickly.
There are two primary types of strokes: ischemic and hemorrhagic. Ischemic strokes, the most common form, happen when a clot obstructs a vessel, stopping blood flow. These clots may form when abnormalities in heart rhythm cause blood to pool and clot, then travel to the brain as emboli. Hemorrhagic strokes occur due to ruptured blood vessels leaking blood into the brain. Both types disrupt brain function, but ischemic strokes are more frequent and typically treated differently.
The brain does not have pain receptors, so blockage is not felt, but oxygen deprivation causes sudden functional impairments such as speech difficulty or muscle weakness, often on one side of the body. The body tries to compensate by rerouting blood flow, but if untreated, brain cells die, causing potentially permanent damage. Prompt medical care is crucial to limit brain injury and improve outcomes.
Treatment mainly involves rapid restoration of blood flow. Tissue plasminogen activator (tPA) is an intravenous medication that dissolves clots if administered early, greatly increasing survival chances and reducing disability. When tPA is unsuitable or ineffective, endovascular thrombectomy can mechanically remove clots using catheters inserted through leg arteries, guided by imaging techniques. Early recognition using the FAT test—checking facial droop, arm weakness, and speech changes—is essential. Immediate emergency response can save lives and reduce long-term impairments.
