How does an obstructed blood vessel lead to a heart attack?

When plaque builds up, it narrows your coronary arteries, decreasing blood flow to your heart. Eventually, the decreased blood flow may cause chest pain (angina), shortness of breath, or other coronary artery disease signs and symptoms. A complete blockage can cause a heart attack

Answer: decreasing blood flow to your heart a complete blockage can cause a heart attack because coronary artery disease often develops over decades you might not notice a problem until you have a significant blockage or a heart attack