Left ventricular hypertrophy can happen when one or more things make your heart work harder than normal to pump blood to your body. For example, if you have high blood pressure, the muscles of the left ventricle must contract more forcefully than normal in order to counter the effect of the elevated blood pressure.

The work of adapting to high blood pressure may result in larger muscle tissue in the walls of the left ventricle. The increase in muscle mass causes the heart to function poorly.

Some factors that can cause your heart to work harder include the following:

  • High blood pressure (hypertension). A blood pressure reading is given in a unit of measure called millimeters of mercury (mm Hg). Hypertension is generally defined as systolic pressure greater than 140 mm Hg and a diastolic pressure greater than 90 mm Hg, or 140/90 mm Hg. Systolic pressure is blood pressure while the heart contracts, and diastolic pressure is blood pressure while the heart rests between beats.
  • Aortic valve stenosis. This disease is a narrowing of the aortic valve, the flap separating your left ventricle from the aorta, the large blood vessel that delivers oxygen-rich blood to your body. This partial obstruction of blood flow requires the left ventricle to work harder to pump blood into the aorta.
  • Hypertrophic cardiomyopathy. In this disease, the heart muscle (myocardium) becomes abnormally thick — or hypertrophied. This thickened heart muscle can make it harder for the heart to pump blood.
  • Athletic training. Intense, prolonged endurance and strength training can cause the heart to adapt so that it can handle the extra workload. In some people, these changes may lead to left ventricular hypertrophy.
Jul. 18, 2012