. Author manuscript; available in PMC: 2013 Aug 1.
Published in final edited form as: J Am Soc Echocardiogr. 2012 Jun 5;25(8):842–854.e6. doi: 10.1016/j.echo.2012.05.004
© 2012 American Society of Echocardiography. Published by Mosby, Inc. All rights reserved.