Fractional flow reserve: physiological basis, advantages and limitations, and potential gender differences

Area of Science:

• Cardiovascular Physiology
• Interventional Cardiology

Background:

• Fractional flow reserve (FFR) assesses coronary artery stenosis severity using pressure gradients.
• Accurate FFR relies on achieving maximal hyperemia via pharmacological vasodilation.
• Microvascular dysfunction can impair hyperemic response, leading to false-normal FFR values.

Purpose of the Study:

• To review the physiological basis, advantages, and limitations of FFR.
• To discuss microvascular dysfunction and its impact on FFR accuracy.
• To address gender-specific considerations in FFR interpretation.

Main Methods:

• Literature review of FFR physiology and microvascular dysfunction.
• Analysis of factors affecting hyperemic response.
• Discussion of clinical implications and gender-specific data.

Main Results:

• Microvascular dysfunction can cause blunted vasodilation, affecting FFR accuracy.
• Potential mechanisms include receptor downregulation, endothelial impairment, or increased vasoconstriction.
• Post-menopausal women may have higher prevalence of microvascular dysfunction.

Conclusions:

• Microvascular dysfunction poses a significant challenge to accurate FFR assessment.
• Understanding these limitations is crucial for appropriate clinical decision-making.
• Gender-specific interpretation guidelines for FFR may be warranted.