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Relationship of vasodilator-induced changes in myocardial oxygenation with the severity of coronary artery stenosis: A study using oxygenation-sensitive cardiovascularmagnetic resonance

journal contribution
posted on 2023-05-19, 09:38 authored by Luu, JM, Friedrich, MG, Harker, J, Nathan DwyerNathan Dwyer, Guensch, D, Mikami, Y, Faris, P, Hare, JL

AIMS: To explore the impact of the functional severity of coronary artery stenosis on changes in myocardial oxygenation during pharmacological vasodilation, using oxygenation-sensitive cardiovascular magnetic resonance (OS-CMR) imaging and invasive fractional flow reserve (FFR). An FFR is considered a standard of reference for assessing haemodynamic relevance of coronary artery stenosis; yet, the relationship of FFR to changes in myocardial oxygenation during vasodilator stress and thus to an objective marker for ischaemia on the tissue level is not well understood.

METHODS AND RESULTS: We prospectively recruited 64 patients with suspected/known coronary artery disease undergoing invasive angiography. The FFR was performed in intermediate coronary artery stenosis. OS-CMR images were acquired using a T2*-sensitive sequence before and after adenosine-induced vasodilation, with myocardial segments matched to angiography. Very strict image quality criteria were defined to ensure the validity of results. The FFR was performed in 37 patients. Because of the strict image quality criteria, 41% of segments had to be excluded, leaving 29/64 patients for the blinded OS-CMR analysis. Coronary territories with an associated FFR of <0.80 showed a lack of increase in myocardial oxygenation [mean signal intensity (ΔSI) -0.49%; 95% confidence interval (CI) -3.78 to 2.78 vs. +7.30%; 95% CI 4.08 to 10.64; P < 0.001]. An FFR of <0.54 best predicted a complete lack of a vasodilator-induced oxygenation increase (sensitivity 71% and specificity 75%). An OS-CMR ΔSI <4.78% identified an FFR of <0.8 with a sensitivity of 86% and specificity of 92%.

CONCLUSION: An FFR of <0.80 is associated with a lack of an adenosine-inducible increase in oxygenation of the dependent coronary territory, while a complete lack of such an increase was best predicted by an FFR of <0.54. Further studies are warranted to identify clinically meaningful cut-off values for FFR measurements and to assess the utility of OS-CMR as an alternative clinical tool for assessing the functional relevance of coronary artery stenosis.

History

Publication title

European Heart Journal Cardiovascular Imaging

Volume

15

Issue

12

Pagination

1358-1367

ISSN

2047-2404

Department/School

Tasmanian School of Medicine

Publisher

Oxford University Press

Place of publication

United Kingdom

Rights statement

Published on behalf of the European Society of Cardiology. All rights reserved. Copyright The Author 2014.

Repository Status

  • Restricted

Socio-economic Objectives

Clinical health not elsewhere classified

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