Meaning
A physical change in the elasticity of major blood vessel walls that alters pressure wave propagation in the circulatory system. In chronic physiological stress, arterial stiffness develops when sustained high blood pressure forces elastin degradation and collagen deposition. This structural rigidity increases the workload of the heart during every contraction.
Biophysical Mechanism
Elastic vessels normally store energy during the peak of cardiac contraction and release it between beats to maintain steady flow. When arterial stiffness rises, the high-pressure wave generated by the heart travels much faster along the rigid vessel wall. This wave returns to the heart too early, colliding with the ongoing ventricular ejection and forcing the heart muscle to pump against higher resistance.
Allostatic Cost
The continuous adaptation to high pressure drains the energetic reserves of the vascular system over years. High systolic peaks injure delicate capillary networks in the brain and kidneys. In response, local microvessels must undergo further protective narrowing, raising systemic resistance.
Therapeutic Constraint
Reversing physical damage to vessel walls requires long periods of controlled pressure rather than temporary drops. Standard medications may lower current pressure but fail to restore elastin fibers that have already fractured. The rigidity persists, which limits the recovery of baseline cardiovascular flexibility.
