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Which diameter and angle rule provides optimal flow patterns in a coronary bifurcation?

Yunlong Huo1, Gérard Finet, Thierry Lefevre

  • 1Department of Biomedical Engineering, IUPUI, Indianapolis, IN 46202, USA.

Journal of Biomechanics
|February 28, 2012
PubMed

Insights

The HK diameter model, based on minimum energy, better predicts coronary artery bifurcations than Murray's model. This finding suggests optimal flow patterns (higher wall shear stress) that may impact percutaneous coronary intervention strategies.

Area of Science:

  • Cardiovascular Science
  • Biomedical Engineering
  • Fluid Dynamics

Background:

  • Epicardial coronary artery bifurcations are crucial in atherogenesis.
  • Murray's cubed diameter law and bifurcation angles were traditionally assumed optimal for flow.
  • A new HK diameter model based on minimum energy has been proposed.

Purpose of the Study:

  • To derive a bifurcation angle rule for the HK diameter model.
  • To compare streamline flow in HK and Murray-type bifurcations.
  • To evaluate the implications for percutaneous coronary intervention.

Main Methods:

  • Analysis of coronary casts to determine adherence to diameter models.
  • Finite element modeling to simulate blood flow patterns.
  • Measurement of inlet velocity and pressure using ComboWire.

Main Results:

  • Coronary bifurcations more closely followed the HK diameter model and angle rule than Murray's model.
  • Murray-type bifurcations showed decreased wall shear stress (WSS) and increased oscillatory shear index (OSI).
  • HK-type bifurcations exhibited more optimal flow patterns with higher WSS and lower OSI.

Conclusions:

  • The HK diameter model and its associated angle rule provide a more accurate representation of coronary artery bifurcations.
  • HK-type bifurcations demonstrate superior flow dynamics compared to traditional Murray-type bifurcations.
  • Findings have significant implications for optimizing bifurcation angles and diameters in percutaneous coronary interventions.

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