ABC | Volume 110, Nº2, February 2018

Short Editorial Mathias Junior Low flow aortic stenosis and projected valve aortic area Arq Bras Cardiol. 2018; 110(2):109-110 Figure 1 – Alternative flow calculation formula where: Q alternative is flow in mL/s, AST LVOT is the sectional transverse area of the left ventricular outflow tract (LVOT) in cm 2 , and Vmean LVOT is the mean blood flow velocity by pulsed wave Doppler at the LVOT level during left ventricular ejection, being expressed in m/s. Figure 2 – Alternative valve area calculation formula where: AVArest is the aortic valve area measured by the continuity equation at rest in cm 2 , AVApeak is the aortic valve area measured by the continuity equation at peak dobutamine infusion in cm 2 , Q rest is the alternative measurement of flow at rest expressed in mL/s, and Q peak is the alternative measurement of flow at peak dobutamine infusion expressed in mL/s. 1. Monin JL, Quere JP, Monchi M, Petit H, Baleynaud S, Chauvel C, et al. Low- gradient aortic stenosis: operative risk stratification and predictors for long- termoutcome: amulticenter study using dobutamine stress hemodynamics. Circulation. 2003;108(3):319-24. 2. Quere JP, Monin JL, Levy F, Petit H, Baleynaud S, Chauvel C, et al. Influence of preoperative left ventricular contractile reserve on postoperative ejection fraction in low-gradient aortic stenosis. Circulation. 2006;113(14):1738-44. 3. Clavel MA, Fuchs C, Burwash IG, Mundigler G, Dumesnit JG, Baumgartner H, et al. Predictors of outcomes in low-flow, low-gradient aortic stenosis: results of the multicenter TOPAS Study. Circulation. 2008;118(14 Suppl):S234-42. 4. Blais C, Burwash IG, Mundigler G, Dumesnil JG, Loho N, Rader F, et al. Projected valve area at normal flow rate improves the assessment of stenosis severity in patients with low-flow, low-gradient aortic stenosis: the multicenter TOPAS (Truly or Pseudo-Severe Aortic Stenosis) study. Circulation. 2006;113(5):711-21. 5. Clavel MA, Burwash IG, Mundigler G, Dumesnil JG, Baumgartner H, Bergler-Klein J, et al. Validation of conventional and simplified methods to calculate projected valve area at normal flow rate in patients with low flow, low gradient aortic stenosis: the multicenter TOPAS (True or Pseudo Severe Aortic Stenosis) Study. J Am Soc Echocardiogr. 2010;23(4):380-6. 6. Ferreira JS, FerreiraNM, Martins SM, et al. An alternativemethod to calculate simplified projected aortic valve area at normal flow rate. Arq Bras Cardiol. 2018; 110(2):132-139. 7. Tribouilloy C, Levy F, Rusinaru D, Gueret P, Petit-Eisenmann H, Baleynaud S, et al. Outcome after aortic valve replacement for low-flow/low- gradient aortic stenosis without contractile reserve on dobutamine stress echocardiography. J Am Coll Cardiol. 2009;53(20):1865-73. References This is an open-access article distributed under the terms of the Creative Commons Attribution License 110