Cardiac Biomechanics
The application of solid and fluid mechanics principles to model heart chamber contraction, blood flow dynamics, and myocardial wall stress.
Governing formula
Wall Stress σ = (P × r) / (2 h) (Law of Laplace for Spheres)
SI unit
kPa (Myocardial Wall Stress) & mmHg (Pressure)
In depth
Applies the Law of Laplace (σ = P r / 2h) to cardiac chambers. Ventricular dilation increases radius r, increasing myocardial wall stress and oxygen demand, which the heart compensates for by thickening wall h (hypertrophy).
Examples in the real world
Pressure-volume loop loops evaluating cardiac stroke work and ejection fraction in heart failure patients.