Your heart pumps blood through your arteries and veins. The measure of that force is called BLOOD PRESSURE. When your heart pumps HARDER than normal, the blood PUSHES more forcefully against the walls of your blood vessels, and that causes HYPERTENSION, or high blood pressure. Blood pressure of 140 over 90 OR higher signals high blood pressure. Hypertension gradually gets worse over the years, and it can lead to some SERIOUS complications. High blood pressure stretches the walls of your arteries, making it more likely that they'll RUPTURE and trigger a STROKE or aneurysm. If you have hypertension, your risk of stroke may be 10 times greater than normal. Hypertension is also a significant risk factor for heart disease. When blood pushes hard against arterial walls, TINY tears often form and create scar tissue. Cholesterol circulating through the bloodstream snags on and ACCUMULATES at those tiny tears. This can narrow the blood vessels and, IF left untreated, can trigger a HEART ATTACK. Hypertension can also trigger formation of blood clots wherever blood vessels are narrowed or damaged. A clot can block blood supply to different parts of your body, triggering a heart attack or stroke. Yet ANOTHER danger to your heart: over time, the heart's muscles and valves may become DAMAGED because of all the extra pressure on them. This CAN lead to heart failure. Finally, you should remember that hypertension doesn't just damage the cardiovascular system. When blood vessels are in trouble, multiple organs are ALSO at risk. Severe hypertension makes you more susceptible to brain aneurysms, blindness AND kidney failure. Hypertension often has no symptoms, which is why it's called the "silent killer." That's why you SHOULD get your blood pressure checked regularly at your doctor's office! Watch other videos in this series to learn more about hypertension and heart disease.