Disorders of the circulatory system
Human heart and circulation · Biology
Study notes
A 50-year-old with 160/100 blood pressure, high LDL cholesterol, and a smoking habit is a walking heart-attack risk — each factor damages arteries, and together they multiply. After a heart attack, doctors open the blocked coronary artery within 90 minutes with angioplasty ('door-to-balloon time') because heart muscle dies fast.