Slice positioning in phase-contrast MRI impacts aortic stenosis assessment

Felix Troger; Christina Tiller; Martin Reindl; Ivan Lechner; Magdalena Holzknecht; Mathias Pamminger; Paulina Poskaite; Christian Kremser; Hanno Ulmer; Elke Ruth Gizewski; Axel Bauer; Sebastian Reinstadler; Bernhard Metzler; Gert Klug; Agnes Mayr

doi:10.1016/j.ejrad.2023.110722

Slice positioning in phase-contrast MRI impacts aortic stenosis assessment

Eur J Radiol. 2023 Apr:161:110722. doi: 10.1016/j.ejrad.2023.110722. Epub 2023 Feb 1.

Authors

Affiliations

¹ University Clinic of Radiology, Medical University of Innsbruck, Anichstrasse 35, 6020 Innsbruck, Austria.
² University Clinic of Internal Medicine III, Cardiology and Angiology, Medical University of Innsbruck, Anichstrasse 35, 6020 Innsbruck, Austria.
³ Department for Medical Statistics, Informatics and Health Economics, Medical University of Innsbruck, Schoepfstrasse 41/1, 6020 Innsbruck, Austria.
⁴ University Clinic of Radiology, Medical University of Innsbruck, Anichstrasse 35, 6020 Innsbruck, Austria. Electronic address: a.mayr@i-med.ac.at.

PMID: 36758278
DOI: 10.1016/j.ejrad.2023.110722

Abstract

Aims: To determine the phase-contrast cardiovascular magnetic resonance imaging (PC-CMR) slice-position above aortic leaflet-attachment-plane (LAP) that provides flow-velocity, -volume and aortic valve area (AVA) measurements with best agreement to invasive and echocardiographic measurements in aortic stenosis (AS).

Methods and results: Fifty-five patients with moderate/severe AS underwent cardiac catheterization, transthoracic echocardiography (TTE) and CMR. Overall, 171 image-planes parallel to LAP were measured via PC-CMR between 22 mm below and 24 mm above LAP. AVA via PC-CMR was calculated as flow-volume divided by peak-velocity during systole. Stroke volume (SV) and AVA were compared to volumetric SV and invasive AVA via the Gorlin-formula, respectively. Above LAP, SV by PC-CMR showed no significant dependence on image-plane-position and correlated strongly with volumetry (rho: 0.633, p < 0.001, marginal-mean-difference (MMD): 1 ml, 95 % confidence-interval (CI): -4 to 6). AVA assessed in image-planes 0-10 mm above LAP differed significantly from invasive measurement (MMD: -0.14 cm², 95 %CI: 0.08-0.21). In contrast, AVA-values by PC-CMR measured 10-20 mm above LAP showed good agreement with invasive determination without significant MMD (0.003 cm², 95 %CI: -0.09 to 0.09). Within these measurements, a plane 15 mm above LAP resulted in the lowest bias (MMD: 0.02 cm², 95 %CI:-0.29 to 0.33). SV and AVA via TTE correlated moderately with volumetry (rho: 0.461, p < 0.001; bias: 15 ml, p < 0.001) and cardiac catheterization (rho: 0.486, p < 0.001, bias: -0.13 cm², p < 0.001), respectively.

Conclusion: PC-CMR measurements at 0-10 mm above LAP should be avoided due to significant AVA-overestimation compared to invasive determination. AVA-assessment by PC-CMR between 10 and 20 mm above LAP did not differ from invasive measurements, with the lowest intermethodical bias measured 15 mm above LAP.

Keywords: Aortic valve stenosis; Cardiac catheterization; Cardiovascular magnetic resonance imaging; Echocardiography; Valvular heart disease.

MeSH terms

Aortic Valve Stenosis* / diagnostic imaging
Aortic Valve Stenosis* / pathology
Aortic Valve* / diagnostic imaging
Aortic Valve* / pathology
Echocardiography
Humans
Magnetic Resonance Imaging
Stroke Volume