Endovascular intervention methods entail creating a temporary capillary block in the vasculature of at least a portion of a patient's organ, such as a hemisphere of the patient's brain, the capillary block essentially blocking blood flow through capillaries in the portion of the patient's organ, and performing the endovascular intervention. Distal embolism protection devices include a blood pump and at least one of a centrifuge element, a dialysis element, a cooling element, and a filtration element. The blood pump is generally capable of drawing blood from a patient's vein, circulating the blood through each of the elements so that a characteristic of a blood component may be manipulated therewith, and perfusing the modified blood into a patient's artery. A capillary block is thereby created in the vasculature of at least a portion of a patient's organ with manipulated blood components.