Enlarged heart. High blood pressure increases the amount of work for your heart. Like any heavily exercised muscle in your body, your heart grows bigger (enlarges) to handle the extra workload. The bigger your heart is, the more it demands oxygen-rich blood but the less able it is to maintain proper blood flow. As a result, you feel weak and tired and are not able to exercise or perform physical activities. Without treatment, your heart failure will only get worse.

Blood pressure is measure in millimeters of mercury (mmHg) and recorded as two numbers, systolic and diastolic. Systolic is the top number (also the higher one), which measure the pressure in the arteries when the heart beats, so when its muscles contract. Diastolic the bottom number (also the lower one), which measures the pressure in the arteries between heart beats, so when the muscles relax and refill with blood.