Grant: Project Grant

Stroke is an injury to the brain caused by a blockage in a brain blood vessel. It is a leading cause of disability and death in Canada and around the world. However, treatments for stroke have improved over the past years with medicines that dissolve the blockage, and minimally invasive surgeries that remove the blockages. These treatments ensure that the blockage is opened but do not guarantee that normal blood flow will return to the brain. Tiny clots can form in little brain vessels which remain blocked and interfere with normal blood flow even when the main blocked artery is treated. This phenomenon is well described in animal studies and imaging studies of stroke patients, and it may explain why some patients fail to recover even with successful therapies. Studies suggest that delivering medications that break clots (lytics) directly into the brain vessel using small tubes (catheters) can help break down these tiny clots and improve brain blood flow. A recent study showed that local lytics (alteplase) significantly improved patients' outcomes by 18% over those who had successful stroke therapies but did not receive local lytics. We aim to validate these findings by testing this technique using a more recent, and pharmacologically superior agent called tenecteplase. Tenecteplase has been shown to have similar safety and benefits as alteplase. Two recent cohort studies showed that tenecteplase is safe when given locally into the affected cerebral arteries. Thus, we aim to test the safety and potential benefit of tenecteplase given locally compared to the standard of care (no local lytic) among 1500 stroke subjects. Subjects' assignment to one of the study arms (local tenecteplase vs no local lytic) will be decided randomly.