The heart muscle, or myocardium, is a specialized type of muscle that makes up the walls of the heart. The myocardium is responsible for contracting and relaxing to pump blood throughout the body.
The heart muscle is unique in that it is constantly active, even when the body is at rest. The myocardium is able to generate its own electrical impulses, which stimulate the contraction of the heart muscle.
The heart muscle is made up of specialized cells called cardiomyocytes, which are connected by intercalated discs. These discs allow for the rapid transmission of electrical signals between cells, allowing the heart to contract in a coordinated and efficient manner.
The heart muscle has two important functions known as systolic and diastolic function. Systolic function refers to the ability of the heart to contract and pump blood out to the body. During systole, the myocardium contracts, and the heart chambers empty out the blood they were holding, sending it out to the lungs and body. Diastolic function, on the other hand, refers to the ability of the heart to relax and fill up with blood. During diastole, the myocardium relaxes, and the heart chambers refill with blood from the veins.
The coordination of these two functions is essential for the proper functioning of the heart and circulation of blood throughout the body. Systolic and diastolic function can be affected by a variety of factors, including damage to the heart muscle, high blood pressure, and certain medical conditions. Measuring and monitoring these functions can be important in diagnosing and managing heart conditions.