key term - Preload

Definition

Preload is the degree of stretch of the cardiac muscle fibers at the end of diastole, just before contraction. It directly influences the force of myocardial contraction according to Frank-Starling law.

Related terms

Cardiac Cycle:

The sequence of mechanical and electrical events that repeat with every heartbeat, including diastole and systole phases.

Frank: Starling Law - A principle stating that the stroke volume of the heart increases in response to an increase in volume of blood filling the heart (the end diastolic volume), when all other factors remain constant.

Stroke Volume:

The amount of blood pumped by one ventricle of the heart with each beat, influenced by preload, afterload, and myocardial contractility