Pullback pressure gradients: Redefining the functional landscape of coronary artery disease

Area of Science:

• Cardiovascular Medicine
• Interventional Cardiology
• Physiology

Background:

• Fractional flow reserve (FFR) is the standard invasive index for epicardial coronary artery disease (CAD) functional significance.
• FFR guides revascularization decisions but may not fully capture heterogeneous CAD patterns.
• Subjective interpretation of pullback pressure curves limits reproducibility.

Purpose of the Study:

• To introduce and critically appraise the novel pullback pressure gradient (PPG) index.
• To highlight PPG's ability to quantitatively characterize coronary artery disease patterns.
• To discuss the clinical evidence and future directions of PPG in coronary physiology.

Main Methods:

• Review of conceptual framework and clinical evidence for PPG.
• Integration of magnitude and longitudinal distribution of pressure gradients.
• Quantitative characterization of CAD on a continuous scale (0-1).

Main Results:

• PPG offers a quantitative alternative to subjective visual interpretation of pullback curves.
• Higher PPG values correlate with focal CAD, while lower values indicate diffuse disease.
• PPG aims to reduce interobserver variability and improve reproducibility in coronary physiology assessment.

Conclusions:

• The pullback pressure gradient (PPG) index provides a novel, quantitative method for assessing coronary artery disease.
• PPG enhances the characterization of CAD heterogeneity beyond traditional FFR.
• Further clinical validation and integration of PPG are expected in contemporary coronary physiology.