Key result
Regionalized CFD model correlates moderately with invasive continuous thermodilution for absolute coronary flow.
Why the study?
Direct absolute coronary flow measurement has not entered routine clinical practice, leaving interventional cardiologists to rely on flow surrogates, prompting evaluation of a new computational fluid dynamics method that regionalizes flow along the artery length.
Does a regionalized porous wall computational fluid dynamics model accurately predict absolute coronary blood flow and microvascular resistance compared to invasive continuous infusion thermodilution in patients with chronic coronary syndrome?
Observational (n=20)
All reconstructions were processed blind to the intra-coronary pressure and CIT results
No
Does a regionalized porous wall computational fluid dynamics model accurately predict absolute coronary blood flow and microvascular resistance compared to invasive continuous infusion thermodilution in patients with chronic coronary syndrome?
This study demonstrates that computational fluid dynamics can regionalize coronary blood flow across main vessels and side branches using standard angiography and pressure wire data, though agreement with invasive thermodilution is modest in minimally diseased arteries and improves with greater epicardial stenosis severity.
Answers are grounded in this paper and cite their sources.
Moderate agreement cautions against clinical adoption of regionalized CFD; leaves open validation in stenotic vessels.
Aims Ischaemic heart disease results from insufficient coronary blood flow. Direct measurement of absolute flow (mL/min) is feasible, but has not entered routine clinical practice in most catheterization laboratories. Interventional cardiologists, therefore, rely on surrogate markers of flow. Recently, we described a computational fluid dynamics (CFD) method for predicting flow that differentiates inlet, side branch, and outlet flows during angiography. In the current study, we evaluate a new method that regionalizes flow along the length of the artery. Methods and results Three-dimensional coronary anatomy was reconstructed from angiograms from 20 patients with chronic coronary syndrome. All flows were computed using CFD by applying the pressure gradient to the reconstructed geometry. Side branch flow was modelled as a porous wall boundary. Side branch flow magnitude was based on morphometric scaling laws with two models: a homogeneous model with flow loss along the entire arterial length; and a regionalized model with flow proportional to local taper. Flow results were validated against invasive measurements of flow by continuous infusion thermodilution (Coroventis™, Abbott). Both methods quantified flow relative to the invasive measures: homogeneous (r 0.47, P 0.006; zero bias; 95% CI −168 to +168 mL/min); regionalized method (r 0.43, P 0.013; zero bias; 95% CI −175 to +175 mL/min). Conclusion During angiography and pressure wire assessment, coronary flow can now be regionalized and differentiated at the inlet, outlet, and side branches. The effect of epicardial disease on agreement suggests the model may be best targeted at cases with a stenosis close to side branches.
No takes yet. Share an insight, caveat, or question.
Taylor et al. (2023) conducted an observational in Suspected myocardial ischaemia with non-obstructive coronary arteries (INOCA) / chronic coronary syndrome (n=20). Computational fluid dynamics (CFD) simulation (virtuQ) with regionalized and homogeneous porous wall boundary methods vs. Invasive continuous infusion thermodilution (CIT) using Rayflow infusion catheter and Coroventis system was evaluated on Correlation and agreement of absolute coronary blood flow (Q, mL/min) between regionalized CFD method and invasive continuous infusion thermodilution (CIT) (r 0.43, zero bias, 95% CI -175 to +175 mL/min, p=0.013). The regionalized computational fluid dynamics model correlated moderately with invasive thermodilution for absolute coronary flow (r=0.43, P=0.013) with zero bias (95% CI -175 to +175 mL/min).
Synapse has enriched 5 closely related papers on similar clinical questions. Consider them for comparative context: