Cardiac function curve In diagrams illustrating the<unk>  of the heart, the y-axis often describes the stroke volume, stroke work, or cardiac output. The x-axis often describes end-diastolic volume, right atrial pressure, or pulmonary capillary wedge pressure. The three curves illustrate that shifts along the same line indicate a change in preload, while shifts from one line to another indicate a change in afterload or contractility. A blood volume increase would cause a shift along the line to the right, which increases left ventricular end diastolic volume (x axis), and therefore also increases stroke volume (y axis). The<unk>  of the heart (also known as<unk> 's law and the<unk><unk>  mechanism) represents the relationship between stroke volume and end diastolic volume. The law states that the stroke volume of the heart increases in response to an increase in the volume of blood in the ventricles, before contraction (the end diastolic volume), when all other factors remain constant. As a larger volume of blood flows into the ventricle, the blood stretches the cardiac muscle fibers, leading to an increase in the force of contraction. The<unk><unk>  mechanism allows the cardiac output to be synchronized with the venous return, arterial blood supply and humoral length, without depending upon external regulation to make alterations. The physiological importance of the mechanism lies mainly in maintaining left and right ventricular output equality.
Frank–Starling law
Mitrofanoff principle
Mandelbaum effect
Arndt–Schulz rule
Haldane effect
Bell–Magendie law
Windkessel effect
Goldwater rule