Absolute assessment of aortic valve stenosis by planimetry using cardiovascular magnetic resonance imaging: Comparison with transœsophageal echocardiography, transthoracic echocardiography, and cardiac catheterisation
Introduction
Assessment of aortic stenosis severity is usually obtained indirectly by calculation of aortic valve area (AVA) using the continuity equation in transthoracic echocardiography (TTE) and Gorlin formula in cardiac catheterisation [1], [2], [3], [4]. Nevertheless, poor echocardiographic windows may compromise measurement accuracy [5], cardiac catheterisation present some risks [6], and Gorlin formula is limited by variations of the empirical constant [7], [8]. Being flow-dependent, indirect methods are invalidated in presence of LV systolic dysfunction or significant aortic regurgitation. Transœsophageal echocardiography (TEE) allows direct evaluation of AVA by planimetry of the orifice but is semi-invasive. Cardiac magnetic resonance (CMR) imaging has been used especially for LV systolic function measurements [9], [10]. New sequences such as true fast imaging steady state free precession (True FISP SSFP) images provide excellent blood-myocardium contrast [11], [12], [13]. To date, only few studies have been performed to evaluate the accuracy of CMR for measurement of stenotic valve areas by jet velocity mapping [14], [15], [16], [17] or by planimetry [12], [18], [19]. Only two of them were performed using True FISP SSFP sequences [12], [18].
Therefore, the aims our study were (1) to evaluate the ability of CMR using True FISP SSFP sequences to perform planimetry of the aortic valve in comparison with TEE planimetry (2) to compare absolute value of AVA to effective AVA evaluation obtained with routine clinical techniques, TTE and cardiac catheterisation.
Section snippets
Patients
The study group consisted in 39 consecutive patients with mild, moderate or severe aortic valve stenosis documented by TTE. They were clinically stable without symptoms that would have contraindicated TEE or CMR. Exclusion criteria were those for TEE (gastro-œsophageal pathology, haemodynamic instability), and CMR suitability (exclusion of metallic implant, severe claustrophobia, pacemaker, valvular prostheses contraindicated in CMR) [20], subvalvular outflow tract obstruction and rapid
Patient population
Twenty (33%) out of 59 consecutive patients were excluded of the study; 12 (20%) patients because of CMR contraindication (four patients with pacemakers, six with metallic implants, and two with severe claustrophobia) and 8 (13%) patients because of TEE contraindication or impossibility to perform the examination. Thirty-nine patients (mean 71.7 ± 7.6 years, ranging from 54 to 83 years) completed the CMR, TTE and TEE protocols. During cardiac catheterisation, the aortic valve was crossed by the
Discussion
This prospective study evaluated AVA area in patients with aortic stenosis using four different imaging techniques. It showed good accordance between CMR planimetry, TEE planimetry and AVA measured by cardiac catheterisation, and good CMR intraobserver and interobserver reproducibilities.
Previous studies have shown the potential for quantitative evaluation of valve stenosis by CMR [14], [15]. Sondergaard et al. used velocity-encoded CMR to estimate orifice area with good correlation with
Conclusion
This work shows that evaluation of AVA by CMR planimetry with new SSFP sequences is accurate, non-invasive and reproducible, and provides a powerful tool for evaluating aortic stenosis. CMR also offers high spatial resolution analysis of myocardial function. CMR planimetry seems particularly helpful in patients with discrepant findings by other modalities and could be an alternative to echocardiography or cardiac catheterisation in selected cases.
Acknowledgment
The investigators are indebted to the staff of the catheterisation laboratory for their help in collecting the data reported in this manuscript.
References (23)
- et al.
Determination of stenotic valve area in adults using Doppler echocardiography
J Am Coll Cardiol
(1986) - et al.
Silent and apparent cerebral embolism after retrograde catheterisation of the aortic valve in valvular stenosis: a prospective, randomised study
Lancet
(2003) - et al.
When should Doppler-determined valve area be better than the Gorlin formula? Variation in hydraulic constants in flow states
J Am Coll Cardiol
(1987) - et al.
Quantification of stenotic mitral valve area with magnetic resonance imaging and comparison with Doppler ultrasound
J Am Coll Cardiol
(2004) - et al.
Valve area and cardiac output in aortic stenosis: quantification by magnetic resonance velocity mapping
Am Heart J
(1993) - et al.
Magnetic resonance to assess the aortic valve area in aortic stenosis: how does it compare to current diagnostic standards?
J Am Coll Cardiol
(2003) Which standard has the gold?
J Am Coll Cardiol
(1992)- et al.
Noninvasive estimation of valve area in patients with aortic stenosis by Doppler ultrasound and two-dimensional echocardiography
Circulation
(1985) - et al.
Hydraulic formula for calculation of the area of the stenotic mitral valve, other clinical measurement
Lancet
(1951) - et al.
Accurate noninvasive quantification of stenotic aortic valve area by Doppler echocardiography
Circulation
(1986)
Reproducibility of Doppler echocardiographic quantification of aortic and mitral valve stenoses: comparison between two echocardiography centres
Am J Cardiol
Cited by (57)
Aortic valve lesions
2021, Medicine (Spain)CMR in Evaluating Valvular Heart Disease: Diagnosis, Severity, and Outcomes
2021, JACC: Cardiovascular ImagingIn vitro correlation between the effective and geometric orifice area in aortic stenosis
2021, Journal of CardiologyCardiovascular magnetic resonance as a complementary method to transthoracic echocardiography for aortic valve area estimation in patients with aortic stenosis: A systematic review and meta-analysis
2021, Hellenic Journal of CardiologyCitation Excerpt :All eligible studies were published after 2002 and conducted in Europe. Six studies had a prospective design,15,16,18,19,22,23 while the remaining were retrospective.13,14,17,20,21,24 CMR examinations were conducted on a 1.5 T scanner in all studies, except for the study by Levy et al23 which was conducted on a 3T scanner.
Contemporary advances in medical imaging
2020, Machine Learning in Cardiovascular MedicineContemporary Imaging of Aortic Stenosis
2019, Heart Lung and CirculationCitation Excerpt :Three dimensional (or at least biplane) TOE is preferred over conventional single plane 2D to compensate for the dynamic systolic aortic annular movement and ensure optimal alignment with the leaflet tips [39–41]. Aortic valve area planimetry by CCT and CMR are available non-invasive alternatives and have been validated against echocardiographic and invasive AVA values [42–47]. However, the feasibility and reliability of all of these approaches will remain limited by artefacts from valvular calcification.