Clot Busters examines the advances, both medical and technological, to the treatment of stroke. Stroke is the fourth leading cause of death in North America, affecting 4.7 million people worldwide each year. One in five women will be affected by stroke-nearly double the number of cases for all forms of cancer. And although risk doubles every 10 years after the age of 55 for both sexes, almost 30 per cent of female stroke patients are under 65 years old.