AUTHOR=Mantini Cesare , Khanji Mohammed Y. , D'Ugo Emilia , Olivieri Marzia , Caputi Cristiano Giovanni , Bufano Gabriella , Mastrodicasa Domenico , Calvo Garcia Darien , Rotondo Domenico , Candeloro Matteo , Tana Claudio , Cademartiri Filippo , Ionescu Adrian , Caulo Massimo , Gallina Sabina , Ricci Fabrizio 

TITLE=Aliased Flow Signal Planimetry by Cardiovascular Magnetic Resonance Imaging for Grading Aortic Stenosis Severity: A Prospective Pilot Study

JOURNAL=Frontiers in Cardiovascular Medicine

VOLUME=8

YEAR=2021

URL=https://www.frontiersin.org/journals/cardiovascular-medicine/articles/10.3389/fcvm.2021.752340

DOI=10.3389/fcvm.2021.752340

ISSN=2297-055X

ABSTRACT=<p><bold>Objectives:</bold> Transthoracic echocardiography (TTE) is the standard technique for assessing aortic stenosis (AS), with effective orifice area (EOA) recommended for grading severity. EOA is operator-dependent, influenced by a number of pitfalls and requires multiple measurements introducing independent and random sources of error. We tested the diagnostic accuracy and precision of aliased orifice area planimetry (AOA<sub>cmr</sub>), a new, simple, non-invasive technique for grading of AS severity by low-VENC phase-contrast cardiovascular magnetic resonance (CMR) imaging.</p><p><bold>Methods:</bold> Twenty-two consecutive patients with mild, moderate, or severe AS and six age- and sex-matched healthy controls had TTE and CMR examinations on the same day. We performed analysis of agreement and correlation among (i) AOA<sub>cmr</sub>; (ii) geometric orifice area (GOA<sub>cmr</sub>) by direct CMR planimetry; (iii) EOA<sub>echo</sub> by TTE-continuity equation; and (iv) the “gold standard” multimodality EOA (EOA<sub>hybrid</sub>) obtained by substituting CMR LVOT area into Doppler continuity equation.</p><p><bold>Results:</bold> There was excellent pairwise positive linear correlation among AOA<sub>cmr</sub>, EOA<sub>hybrid</sub>, GOA<sub>cmr</sub>, and EOA<sub>echo</sub> (<italic>p</italic> &lt; 0.001); AOA<sub>cmr</sub> had the highest correlation with EOA<sub>hybrid</sub> (<italic>R</italic><sup>2</sup> = 0.985, <italic>p</italic> &lt; 0.001). There was good agreement between methods, with the lowest bias (0.019) for the comparison between AOA<sub>cmr</sub> and EOA<sub>hybrid</sub>. AOA<sub>cmr</sub> yielded excellent intra- and inter-rater reliability (intraclass correlation coefficient: 0.997 and 0.998, respectively).</p><p><bold>Conclusions:</bold> Aliased orifice area planimetry by 2D phase contrast imaging is a simple, reproducible, accurate “one-stop shop” CMR method for grading AS, potentially useful when echocardiographic severity assessment is inconclusive or discordant. Larger studies are warranted to confirm and validate these promising preliminary results.</p>