Functional aortic valve area differs significantly between sexes: A phase-contrast cardiac MRI study in patients with severe aortic stenosis

Felix Troger; Christian Kremser; Mathias Pamminger; Sebastian J Reinstadler; Gudrun C Thurner; Benjamin Henninger; Gert Klug; Bernhard Metzler; Agnes Mayr

doi:10.1016/j.ijcha.2024.101357

Functional aortic valve area differs significantly between sexes: A phase-contrast cardiac MRI study in patients with severe aortic stenosis

Int J Cardiol Heart Vasc. 2024 Feb 6:51:101357. doi: 10.1016/j.ijcha.2024.101357. eCollection 2024 Apr.

Authors

Felix Troger¹, Christian Kremser¹, Mathias Pamminger¹, Sebastian J Reinstadler², Gudrun C Thurner³, Benjamin Henninger¹, Gert Klug⁴, Bernhard Metzler², Agnes Mayr¹

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 Institute of Pathology, Neuropathology and Molecular Pathology, Medical University of Innsbruck, Müllerstraße 44 6020, Innsbruck, Austria.
⁴ Department of Internal Medicine, County Hospital Bruck an der Mur, Tragoesser Strasse 1 8600, Bruck an der Mur, Austria.

Abstract

Background: Aortic stenosis (AS) is one of the most prevalent valvular heart-diseases in Europe. Currently, diagnosis and classification are not sex-sensitive; however, due to a distinctly different natural history of AS, further investigations of sex-differences in AS-patients are needed. Thus, this study aimed to detect sex-differences in severe AS, especially concerning flow-patterns, via phase-contrast cardiac magnetic resonance imaging (PC-CMR).

Methods: Forty-four severe AS-patients (20 women, 45 % vs. 24 men, 55 %) with a median age of 72 years underwent transthoracic echocardiography (TTE), cardiac catheterization (CC) and CMR. Aortic valve area (AVA) and stroke volume (SV) were determined in all modalities, with CMR yielding geometrical AVA via cine-planimetry and functional AVA via PC-CMR, the latter being also used to examine flow-properties.

Results: Geometrical AVA showed no sex-differences (0.91 cm², IQR: 0.61-1.14 vs. 0.94 cm², IQR: 0.77-1.22, p = 0.322). However, functional AVA differed significantly between sexes in all three modalities (TTE: p = 0.044; CC/PC-CMR: p < 0.001). In men, no significant intermethodical biases in functional AVA-measurements between modalities were found (p = 0.278); yet, in women the particular measurements differed significantly (p < 0.001). Momentary flowrate showed sex-differences depending on momentary opening-degree (at 50 %, 75 % and 90 % of peak-AVA, all p < 0.001), with men showing higher flowrates with increasing opening-area. In women, flowrate did not differ between 75 % and 90 % of peak-AVA (p = 0.191).

Conclusions: In severe AS-patients, functional AVA showed marked sex-differences in all modalities, whilst geometrical AVA did not differ. Inter-methodical biases were negligible in men, but not in women. Lastly, significant sex-differences in flow-patterns fit in with the different pathogenesis of AS.

Keywords: Aortic Stenosis; Cardiovascular MRI; Phase-Contrast MRI; Sex Differences.