Usefulness of global left ventricular longitudinal strain for risk stratification in low ejection fraction, low-gradient aortic stenosis: results from the multicenter True or Pseudo-Severe Aortic Stenosis study. - Dahou A; Bartko PE; Capoulade R; Clavel MA; Mundigler G; Grondin SL; Bergler-Klein J; Burwash I; Dumesnil JG; Sénéchal M; O'Connor K; Baumgartner H; et al. (Circulation. Cardiovascular imaging, 2015)