Stroke. Conceptual image of the word stroke spelt using tiles from the board game Scrabble. A stroke (or cerebrovascular accident, CVA) is brain damage caused by an interruption in the brain's blood supply or by the leakage of blood through blood vessel walls. The two main causes of a stroke are high blood pressure and atherosclerosis (narrowing of the arteries due to fat deposition). Strokes vary in severity according to the location and extent of the damage, but can result in long-term paralysis, coma and even death.