Frank-Starling mechanism
The intrinsic cardiac property whereby increased venous return and ventricular filling enhances subsequent contractile force and stroke volume.
Full Definition
The Frank-Starling mechanism is a fundamental cardiac regulatory principle describing the heart's ability to automatically adjust its output based on venous return. As venous return increases, the ventricle stretches during diastole, optimizing actin-myosin crossbridge formation and increasing the force of the subsequent contraction. This results in greater stroke volume and cardiac output without requiring external neural or hormonal stimulation. In sports cardiology, understanding this mechanism is crucial for interpreting exercise adaptations, cardiac remodeling patterns, and distinguishing physiological from pathological responses to increased preload. The mechanism becomes particularly relevant when evaluating athletes with volume-loaded hearts.
Usage
Usage note: Capitalize both proper names; hyphenate when used as compound modifier; explain physiological context.
In Context
- "The endurance athlete's enlarged left ventricle demonstrates enhanced Frank-Starling mechanism utilization during maximal exercise." — Cardiac imaging report
- "Impaired Frank-Starling mechanism may explain the reduced exercise capacity observed in this athlete with early cardiomyopathy." — Clinical assessment