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. 2021 Nov 16;10(22):e021126.
doi: 10.1161/JAHA.121.021126. Epub 2021 Oct 30.

Prevalence and Outcomes of Low-Gradient Severe Aortic Stenosis-From the National Echo Database of Australia

Afik D Snir  1 , Martin K Ng  1   2 , Geoff Strange  3   4 , David Playford  4 , Simon Stewart  5   6 , David S Celermajer  1   2   3
Affiliations

Prevalence and Outcomes of Low-Gradient Severe Aortic Stenosis-From the National Echo Database of Australia

Afik D Snir et al. J Am Heart Assoc. .

Abstract

Background The prevalence and outcomes of the different subtypes of severe low-gradient aortic stenosis (AS) in routine clinical cardiology practice have not been well characterized. Methods and Results Data were derived from the National Echocardiography Database of Australia. Of 192 060 adults (aged 62.8±17.8 [mean±SD] years) with native aortic valve profiling between 2000 and 2019, 12 013 (6.3%) had severe AS. Of these, 5601 patients (47%) had high-gradient and 6412 patients (53%) had low-gradient severe AS. The stroke volume index was documented in 2741 (42.7%) patients with low gradient; 1750 patients (64%) with low flow, low gradient (LFLG); and 991 patients with normal flow, low gradient. Of the patients with LFLG, 1570 (89.7%) had left ventricular ejection fraction recorded; 959 (61%) had paradoxical LFLG (preserved left ventricular ejection fraction), and 611 (39%) had classical LFLG (reduced left ventricular ejection fraction). All-cause and cardiovascular-related mortality were assessed in the 8162 patients with classifiable severe AS subtype during a mean±SD follow-up of 88±45 months. Actual 1-year and 5-year all-cause mortality rates varied across these groups and were 15.8% and 49.2% among patients with high-gradient severe AS, 11.6% and 53.6% in patients with normal-flow, low-gradient severe AS, 16.9% and 58.8% in patients with paradoxical LFLG severe AS, and 30.5% and 72.9% in patients with classical LFLG severe AS. Compared with patients with high-gradient severe AS, the 5-year age-adjusted and sex-adjusted mortality risk hazard ratios were 0.94 (95% CI, 0.85-1.03) in patients with normal-flow, low-gradient severe AS; 1.01 (95% CI, 0.92-1.12) in patients with paradoxical LFLG severe AS; and 1.65 (95% CI, 1.48-1.84) in patients with classical LFLG severe AS. Conclusions Approximately half of those patients with echocardiographic features of severe AS in routine clinical practice have low-gradient hemodynamics, which is associated with long-term mortality comparable with or worse than high-gradient severe AS. The poorest survival was associated with classical LFLG severe AS.

Keywords: aortic stenosis; low flow, low gradient; low gradient; normal flow, low gradient.

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Conflict of interest statement

Dr Ng reports grants from Edwards LifeSciences and grants from Abbott outside the submitted work. Dr Strange reports grants and personal fees from Edwards LifeSciences and personal fees from The National Echocardiography Database of Australia Ltd. outside the submitted work. Dr Playford reports grants from Edwards LifeSciences and grants from Novartis outside the submitted work. Dr Stewart reports personal fees from Edwards LifeSciences and personal fees from The National Echocardiography Database of Australia during the conduct of the study and grants from the National Health and Medical Research Council of Australia outside the submitted work. The remaining authors have no disclosures to report.

Figures

Figure 1
Figure 1. Study flowchart.
The main analyzed study cohort included 8162 patients with severe AS: 5601 high gradient, 991 NFLG, 611 classical LFLG, and 959 paradoxical LFLG. AS indicates aortic stenosis; AV, aortic valve; AVA, aortic valve area; AVR, aortic valve replacement; LFLG, low flow, low gradient; LVEF, left ventricular ejection fraction; MG, Mean Gradient; NEDA, National Echo Database of Australia; NFLG, normal‐flow, low‐gradient; PV, Peak Velocity; SVI, stroke volume index; and TTE, transthoracic echocardiogram.
Figure 2
Figure 2. One‐year all‐cause and CV‐related mortality.
Kaplan‐Meier curves for all‐cause mortality (Left Hand Side) and CV‐related mortality (Right Hand Side), including the results of Cox regression analyses showing adjusted (age and sex) HR (95% CI) and P values compared with the high‐gradient severe aortic stenosis subgroup. CV indicates cardiovascular; HR, hazard ratio; LFLG, low flow, low gradient; NFLG, normal flow, low gradient; and Ref, reference.
Figure 3
Figure 3. Five‐year all‐cause and CV‐related mortality.
Kaplan‐Meier curves for all‐cause mortality (LHS) and CV‐related mortality (RHS), including the results of Cox regression analyses showing adjusted (age and sex) HR (95% CI) and P values compared with the high‐gradient severe aortic stenosis subgroup. CV indicates cardiovascular; HR, hazard ratio; LFLG, low flow, low gradient; NFLG, normal flow, low gradient; and Ref, reference.
Figure 4
Figure 4. Cardiovascular‐related vs other causes of mortality according to severe aortic stenosis subgroup.
Recorded cause of death (cardiovascular related vs not cardiovascular related) according to severe aortic stenosis subgroup for both 1‐year (top) and 5‐year (bottom) mortality. CVD indicates cardiovascular disease; LFLG, low flow, low gradient; and NFLG, normal flow, low gradient.
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References

    1. Carabello BA, Paulus WJ. Aortic stenosis. Lancet. 2009;373:956–966. doi: 10.1016/S0140-6736(09)60211-7 - DOI - PubMed
    1. Baumgartner H, Falk V, Bax JJ, De Bonis M, Hamm C, Holm PJ, Iung B, Lancellotti P, Lansac E, Rodriguez Muñoz D, et al. 2017 ESC/EACTS Guidelines for the management of valvular heart disease. Eur Heart J. 2017;38:2739–2791. doi: 10.1093/eurheartj/ehx391 - DOI - PubMed
    1. Clavel M‐A, Magne J, Pibarot P. Low‐gradient aortic stenosis. Eur Heart J. 2016;37:2645–2657. doi: 10.1093/eurheartj/ehw096 - DOI - PMC - PubMed
    1. Strange G, Stewart S, Celermajer D, Prior D, Scalia GM, Marwick T, Ilton M, Joseph M, Codde J, Playford D. Poor long‐term survival in patients with moderate aortic stenosis. J Am Coll Cardiol. 2019;74:1851–1863. doi: 10.1016/j.jacc.2019.08.004 - DOI - PubMed
    1. Kang D‐H, Jang JY, Park S‐J, Kim D‐H, Yun S‐C, Song J‐M, Park SW, Chung C‐H, Song J‐K, Lee J‐W. Watchful observation versus early aortic valve replacement for symptomatic patients with normal flow, low‐gradient severe aortic stenosis. Heart. 2015;101:1375–1381. doi: 10.1136/heartjnl-2015-307528 - DOI - PubMed

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