Szívizomkontrakció

Szívizomkontrakció refers to the process by which the heart muscle, or myocardium, shortens and generates force, propelling blood throughout the body. This essential function is a complex interplay of electrical and mechanical events. The process begins with an electrical impulse originating in the sinoatrial node, the heart's natural pacemaker. This impulse spreads rapidly through the cardiac muscle cells, triggering the release of calcium ions within these cells. The influx of calcium ions initiates a cascade of biochemical events, leading to the interaction of actin and myosin filaments within the muscle fibers. These filaments slide past each other, causing the cardiac muscle cells to shorten and contract. This coordinated contraction of the entire heart muscle creates the pressure needed to eject blood from the heart chambers into the arteries. Following contraction, a period of relaxation, known as diastole, occurs, allowing the heart chambers to refill with blood in preparation for the next contraction. The rhythmic and efficient nature of szívizomkontrakció is vital for maintaining adequate blood circulation and oxygen delivery to all tissues and organs of the body.