B. Iung, A prospective survey of patients with valvular heart disease in Europe: The Euro Heart Survey on Valvular Heart Disease, Eur Heart J. juill, vol.24, issue.13, pp.1231-1274, 2003.

V. T. Nkomo, J. M. Gardin, T. N. Skelton, J. S. Gottdiener, C. G. Scott et al., Burden of valvular heart diseases: a population-based study, Lancet Lond Engl. 16 sept, vol.368, issue.9540, pp.1005-1016, 2006.

C. M. Otto, B. K. Lind, D. W. Kitzman, B. J. Gersh, and D. S. Siscovick, Association of aortic-valve sclerosis with cardiovascular mortality and morbidity in the elderly, N Engl J Med. 15 juill, vol.341, issue.3, pp.142-149, 1999.

W. C. Roberts and J. M. Ko, Frequency by decades of unicuspid, bicuspid, and tricuspid aortic valves in adults having isolated aortic valve replacement for aortic stenosis, with or without associated aortic regurgitation, Circulation. 22 févr, vol.111, issue.7, pp.920-925, 2005.

K. D. O'brien, D. M. Shavelle, M. T. Caulfield, T. O. Mcdonald, K. Olin-lewis et al., Association of angiotensin-converting enzyme with low-density lipoprotein in aortic valvular lesions and in human plasma, Circulation, vol.106, issue.17, pp.2224-2254, 2002.

E. R. Mohler, F. Gannon, C. Reynolds, R. Zimmerman, M. G. Keane et al., Bone formation and inflammation in cardiac valves, Circulation. 20 mars, vol.103, issue.11, pp.1522-1530, 2001.

B. F. Stewart, D. Siscovick, B. K. Lind, J. M. Gardin, J. S. Gottdiener et al., Clinical factors associated with calcific aortic valve disease. Cardiovascular Health Study, J Am Coll Cardiol. 1 mars, vol.29, issue.3, pp.630-634, 1997.

N. M. Rajamannan, Low-density lipoprotein and aortic stenosis, Heart Br Card Soc. sept, vol.94, issue.9, pp.1111-1113, 2008.

D. Messika-zeitoun, L. F. Bielak, P. A. Peyser, P. F. Sheedy, S. T. Turner et al., Aortic valve calcification: determinants and progression in the population, Arterioscler Thromb Vasc Biol. mars, vol.27, issue.3, pp.642-650, 2007.

V. Garg, A. N. Muth, J. F. Ransom, M. K. Schluterman, R. Barnes et al., Mutations in NOTCH1 cause aortic valve disease, Nature. 8 sept, vol.437, issue.7056, pp.270-274, 2005.

G. Thanassoulis, C. Y. Campbell, D. S. Owens, J. G. Smith, A. V. Smith et al., Genetic Associations with Valvular Calcification and Aortic Stenosis

C. M. Otto, Calcific aortic stenosis--time to look more closely at the valve, N Engl J Med. 25 sept, vol.359, issue.13, pp.1395-1403, 2008.

H. Baumgartner, J. Hung, J. Bermejo, J. B. Chambers, T. Edvardsen et al., Recommendations on the echocardiographic assessment of aortic valve stenosis: a focused update from the European Association of Cardiovascular Imaging and the American Society of Echocardiography, Eur Heart J Cardiovasc Imaging. 1 mars, vol.18, issue.3, pp.254-75, 2017.

V. Falk, P. J. Holm, B. Iung, P. Lancellotti, E. Lansac et al., ESC/EACTS Guidelines for the management of valvular heart disease, p.53, 2017.

R. Rosenhek, T. Binder, G. Porenta, I. Lang, G. Christ et al., Predictors of outcome in severe, asymptomatic aortic stenosis, N Engl J Med. 31 août, vol.343, issue.9, pp.611-618, 2000.

J. Bergler-klein, U. Klaar, M. Heger, R. Rosenhek, G. Mundigler et al., Natriuretic peptides predict symptom-free survival and postoperative outcome in severe aortic stenosis, Circulation. 18 mai, vol.109, pp.2302-2310, 2004.

D. M. Zlotnick, M. L. Ouellette, D. J. Malenka, J. P. Desimone, B. J. Leavitt et al., Effect of preoperative pulmonary hypertension on outcomes in patients with severe aortic stenosis following surgical aortic valve replacement, Am J Cardiol, vol.112, issue.10, pp.1635-1675, 2013.

J. Minners, M. Allgeier, C. Gohlke-baerwolf, R. P. Kienzle, F. J. Neumann et al., Inconsistent grading of aortic valve stenosis by current guidelines: haemodynamic studies in patients with apparently normal left ventricular function, Heart, vol.96, pp.1463-1471, 2010.

J. L. Monin, M. Monchi, V. Gest, A. M. Duval-moulin, J. L. Dubois-rande et al., Aortic stenosis with severe left ventricular dysfunction and low transvalvular pressure gradients: risk stratification by low-dose dobutamine echocardiography, J Am Coll Cardiol. 15 juin, vol.37, issue.8, pp.2101-2108, 2001.

R. A. Nishimura, J. A. Grantham, H. M. Connolly, H. V. Schaff, S. T. Higano et al., Low-output, low-gradient aortic stenosis in patients with depressed left ventricular systolic function: the clinical utility of the dobutamine challenge in the catheterization laboratory, Circulation. 13 août, vol.106, issue.7, pp.809-822, 2002.

E. Fougères, C. Tribouilloy, M. Monchi, H. Petit-eisenmann, S. Baleynaud et al., Outcomes of pseudo-severe aortic stenosis under conservative treatment, Eur Heart J, vol.33, pp.2426-2459, 2012.

Z. Hachicha, J. G. Dumesnil, P. Bogaty, and P. Pibarot, Paradoxical low-flow, low-gradient severe aortic stenosis despite preserved ejection fraction is associated with higher afterload and reduced survival, Circulation. 5 juin, vol.115, issue.22, pp.2856-64, 2007.

C. Cueff, J. Serfaty, C. Cimadevilla, J. Laissy, D. Himbert et al., Measurement of aortic valve calcification using multislice computed tomography: correlation with haemodynamic severity of aortic stenosis and clinical implication for patients with low ejection fraction, Heart Br Card Soc. mai, vol.97, issue.9, pp.721-727, 2011.

P. Mehrotra, K. Jansen, A. W. Flynn, T. C. Tan, S. Elmariah et al., Differential left ventricular remodelling and longitudinal function distinguishes low flow from normal-flow preserved ejection fraction low-gradient severe aortic stenosis, Eur Heart J. juill, vol.34, issue.25, pp.1906-1920, 2013.

C. Tribouilloy, D. Rusinaru, S. Maréchaux, A. Castel, N. Debry et al., Low-gradient, low-flow severe aortic stenosis with preserved left ventricular ejection fraction: characteristics, outcome, and implications for surgery, J Am Coll Cardiol. 6 janv, vol.65, issue.1, pp.55-66, 2015.

D. Kang, J. Y. Jang, S. Park, D. Kim, Y. Song et al., Watchful observation versus early aortic valve replacement for symptomatic patients with normal flow, low-gradient severe aortic stenosis, Heart Br Card Soc. sept, vol.101, issue.17, pp.1375-81, 2015.

M. Berthelot-richer, P. Pibarot, R. Capoulade, J. G. Dumesnil, A. Dahou et al., Discordant Grading of Aortic Stenosis Severity: Echocardiographic Predictors of Survival Benefit Associated With Aortic Valve Replacement, JACC Cardiovasc Imaging, vol.9, issue.7, pp.797-805, 2016.

V. Dayan, G. Vignolo, J. Magne, M. Clavel, D. Mohty et al., Outcome and Impact of Aortic Valve Replacement in Patients With Preserved LVEF and Low-Gradient Aortic Stenosis, J Am Coll Cardiol. 15 déc, vol.66, issue.23, pp.2594-603, 2015.
URL : https://hal.archives-ouvertes.fr/hal-02320247

O. Zusman, G. S. Pressman, S. Banai, A. Finkelstein, and Y. Topilsky, Intervention Versus Observation in Symptomatic Patients With Normal Flow Low Gradient Severe Aortic Stenosis, JACC Cardiovasc Imaging. sept, vol.11, issue.9, pp.1225-1257, 2018.

B. A. Carabello, Aortic Stenosis, N Engl J Med. 28 févr, vol.346, issue.9, pp.677-82, 2002.

Z. William and A. Low-gradient, Aortic Stenosis With Normal Systolic Function, Circulation. 1 mars, vol.123, issue.8, pp.838-878, 2011.

L. Ven, F. Freeman, M. Webb, J. Clavel, M. Wheeler et al., Impact of low flow on the outcome of high-risk patients undergoing transcatheter aortic valve replacement, J Am Coll Cardiol. 27 août, vol.62, issue.9, pp.782-790, 2013.

M. F. Eleid, K. Goel, M. H. Murad, P. J. Erwin, R. M. Suri et al., Meta-Analysis of the Prognostic Impact of Stroke Volume, Gradient, and Ejection Fraction After Transcatheter Aortic Valve Implantation, Am J Cardiol. 15 sept, vol.116, issue.6, pp.989-94, 2015.

L. Kadem, P. Pibarot, J. G. Dumesnil, F. Mouret, V. Garitey et al., Independent contribution of left ventricular ejection time to the mean gradient in aortic stenosis, J Heart Valve Dis. sept, vol.11, issue.5, pp.615-638, 2002.

N. S. Chahal, M. Drakopoulou, A. M. Gonzalez-gonzalez, R. Manivarmane, R. Khattar et al., Resting Aortic Valve Area at Normal Transaortic Flow Rate Reflects True Valve Area in Suspected Low-Gradient Severe Aortic Stenosis, JACC Cardiovasc Imaging, vol.8, issue.10, pp.1133-1142, 2015.

L. Kadem, J. G. Dumesnil, R. Rieu, L. Durand, D. Garcia et al., Impact of systemic hypertension on the assessment of aortic stenosis, Heart Br Card Soc. mars, vol.91, issue.3, pp.354-61, 2005.
URL : https://hal.archives-ouvertes.fr/hal-00015469

M. Clavel, D. Messika-zeitoun, P. Pibarot, S. R. Aggarwal, J. Malouf et al., The complex nature of discordant severe calcified aortic valve disease grading: new insights from combined Doppler echocardiographic and computed tomographic study, J Am Coll Cardiol. 17 déc, vol.62, issue.24, pp.2329-2367, 2013.

N. Côté, L. Simard, A. Zenses, L. Tastet, M. Shen et al., Impact of Vascular Hemodynamics on Aortic Stenosis Evaluation: New Insights Into the Pathophysiology of Normal Flow-Small Aortic Valve Area-Low Gradient Pattern, J Am Heart Assoc. 7 juill, vol.6, issue.7, 2017.

M. Clavel, E. Guzzetti, M. Annabi, E. Salaun, G. Ong et al., Normal-Flow Low-Gradient Severe Aortic Stenosis: Myth or Reality? Struct Heart, vol.4, pp.180-187, 2018.

M. E. Charlson, P. Pompei, K. L. Ales, and C. R. Mackenzie, A new method of classifying prognostic comorbidity in longitudinal studies: development and validation, J Chronic Dis, vol.40, issue.5, pp.373-83, 1987.

P. J. Currie, J. B. Seward, G. S. Reeder, R. E. Vlietstra, D. R. Bresnahan et al., Continuouswave Doppler echocardiographic assessment of severity of calcific aortic stenosis: a simultaneous Doppler-catheter correlative study in 100 adult patients, Circulation. juin, vol.71, issue.6, pp.1162-1171, 1985.

A. Evangelista, D. Garcia-dorado, G. Del-castillo, H. Gonzalez-alujas, T. Soler-soler et al., Cardiac index quantification by Doppler ultrasound in patients without left ventricular outflow tract abnormalities, J Am Coll Cardiol. 1 mars, vol.25, issue.3, pp.710-716, 1995.

H. Baumgartner, H. Kratzer, G. Helmreich, and P. Kuehn, Determination of aortic valve area by Doppler echocardiography using the continuity equation: a critical evaluation, Cardiology, vol.77, issue.2, pp.101-112, 1990.

R. M. Lang, L. P. Badano, V. Mor-avi, J. Afilalo, A. Armstrong et al., Recommendations for cardiac chamber quantification by echocardiography in adults: an update from the American Society of Echocardiography and the European Association of Cardiovascular Imaging, J Am Soc Echocardiogr Off Publ Am Soc Echocardiogr. janv, vol.28, issue.1, pp.1-39, 2015.

P. Lancellotti, J. Magne, D. E. , D. L. O'connor, K. Rosca et al., Clinical outcome in asymptomatic severe aortic stenosis: insights from the new proposed aortic stenosis grading classification, J Am Coll Cardiol. 17 janv, vol.59, issue.3, pp.235-278, 2012.
URL : https://hal.archives-ouvertes.fr/hal-00904869

S. Saeed, A. Vamvakidou, R. Seifert, R. Khattar, W. Li et al., The impact of aortic valve replacement on survival in patients with normal flow low gradient severe aortic stenosis: a propensity-matched comparison, Eur Heart J Cardiovasc Imaging. 21 juill, 2019.

;. Chadha and . Chadha, J Am Heart Assoc

, JAHA

C. Tribouilloy, D. Rusinaru, V. Charles, J. Boulif, F. Maes et al., Progression of Low-Gradient, Low-Flow, Severe Aortic Stenosis With Preserved Left Ventricular Ejection Fraction, Am J Cardiol. 15 août, vol.116, issue.4, pp.612-619, 2015.

R. V. Freeman and C. M. Otto, Spectrum of calcific aortic valve disease: pathogenesis, disease progression, and treatment strategies, Circulation. 21 juin, vol.111, issue.24, pp.3316-3342, 2005.