Is axial wall stress compressive in certain arteries?

Area of Science:

• Biomedical Engineering
• Computational Biology
• Cardiovascular Physiology

Background:

• The conventional definition of the zero-stress state in blood vessels uses atmospheric pressure, leading to tensile stress calculations.
• This conventional approach may overlook the potential for compressive stresses within vessel walls under physiological conditions.

Purpose of the Study:

• To investigate the impact of defining the zero-stress state with reference to vacuum pressure versus atmospheric pressure on blood vessel wall stress calculations.
• To determine if axial wall stress can be compressive in blood vessels under physiological conditions.

Main Methods:

• Mathematical-physical modeling of blood vessels.
• Calculation of radial, circumferential, and axial wall stresses using both conventional (atmospheric pressure) and unconventional (vacuum pressure) zero-stress state definitions.
• Analysis of stress distributions in three representative vessel examples.

Main Results:

• The study suggests that axial wall stress may indeed be compressive in many blood vessels when using an unconventional zero-stress state definition.
• Significant differences were observed between stress values calculated using conventional and unconventional methods.
• The ratios of calculated stresses are highly dependent on the chosen zero-stress state definition.

Conclusions:

• The choice of zero-stress state definition critically influences the calculated stresses in blood vessel walls.
• Axial wall stress could be compressive in physiological conditions, which has implications for understanding vessel structure, growth, and adaptation.
• Further research is needed to explore the functional significance of compressive stresses in vascular mechanics.