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Published on: June 28, 2019

Fractional flow reserve--the influence of the collateral circulation

Narbeh Melikian, Thomas Cuisset, Michalis Hamilos

    International Journal of Cardiology
    |December 7, 2007
    PubMed

    Insights

    Fractional flow reserve (FFR) can be affected by major collateral vessels, potentially altering its accuracy in assessing coronary artery stenosis. This case study explores the physiological reasons behind this FFR modification.

    Area of Science:

    • Cardiovascular physiology
    • Interventional cardiology

    Background:

    • Fractional flow reserve (FFR) is a standard invasive metric for evaluating the physiological significance of coronary artery stenosis.
    • FFR measurements are generally considered independent of systemic hemodynamic factors like blood pressure and heart rate, and the specific coronary vessel being analyzed.

    Observation:

    • This report details a clinical case where the true Fractional flow reserve value appeared to be influenced by the presence of significant major collateral vessels.
    • The observation suggests that collateral circulation may impact the accuracy of FFR in specific scenarios.

    Findings:

    • The study highlights that while FFR is robust against many variables, major collateral flow can indeed alter the measured FFR.
    • A potential physiological mechanism explaining how collateral vessels can modify the pressure gradient and thus the FFR is discussed.

    Implications:

    • Understanding the impact of collateral vessels on FFR is crucial for accurate stenosis assessment in complex coronary artery disease.
    • This finding may necessitate adjustments in the interpretation of FFR in patients with extensive collateral networks.

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