Heart muscle thickened | Myocardium

Heart muscle thickened

If the heart muscles thicken, this is often a consequence of chronic overloading of the heart.If one speaks of the fact that the heart muscle is thickened (hypertrophy), the left ventricle is usually meant. This is usually between 6 and 12 millimeters thick. Due to chronic overloading in cases of high blood pressure, for example, the heart must always eject the blood from the left chamber into the body’s circulation against much greater resistance in the aorta than is normally the case.

This causes the heart to adapt to the higher resistance and its muscle cells start to grow (no proliferation of individual cells) to apply more force and the heart muscle thickens. The more the heart muscle thickens, the less volume the left ventricle can absorb from the left atrium. In most cases there is an enlargement of only one side of the heart (asymmetrical), which leads to a disturbed pumping process.

The left ventricle is now filled with blood faster because its radius is smaller compared to the right ventricle, but it contains less blood and loses elasticity due to growth. Therefore, it ejects less blood into the body’s circulation per beat. In addition, larger muscle cells require more oxygen, which increases the risk of an oxygen deficiency and thus the risk of heart attack.

The thickening of the heart muscle as a result of high blood pressure must be distinguished from thickening due to heavy physical exertion. Here the entire heart (not only the left ventricle) grows and a higher cardiac output is achieved with a secure oxygen supply.