Cardiac Autonomic Response to Active Standing in Calcific Aortic Valve Stenosis.By José M. Torres-Arellano, Juan C. Echeverría, Nydia Ávila-Vanzzini, Rashidi Springall, Andrea Toledo, Oscar Infante, Rafael Bojalil, Jorge E. Cossío-Aranda, Erika Fajardo and Claudia Lerma