[1] Inst Mexicano Seguro Social, Ctr Med Nacl Siglo 21, Hosp Cardiol, Dept Heart Failure, Mexico City, DF, Mexico
[2] Inst Mexicano Seguro Social, Ctr Med Nacl Siglo 21, Hosp Cardiol, Dept Res & Direct, Mexico City, DF, Mexico
[3] Inst Nacl Cardiol Ignacio Chavez, Dept Echocardiog, Mexico City, DF, Mexico
[4] Inst Mexicano Seguro Social, Ctr Med Nacl Siglo 21, Hosp Cardiol, Dept Lab, Mexico City, DF, Mexico
[5] Inst Mexicano Seguro Social, Ctr Med Nacl Siglo 21, Hosp Cardiol, Unidad Invest Med Enfermedades Metab, Mexico City, DF, Mexico
[6] Hosp Clin Barcelona, Dept Cardiol, Barcelona, Spain
[7] Inst Nacl Cardiol Ignacio Chavez, Dept Nucl Med, Mexico City, DF, Mexico
[8] Inst Nacl Enfermedades Resp Ismael Cosio Villegas, Cardiol Dept, Mexico City, DF, Mexico
[9] Hosp Infantil Mexico Dr Federico Gomez, Directorate Res, Mexico City, DF, Mexico
[10] Yale Univ, Sch Med, Dept Internal Med, Sect Cardiovasc Med, New Haven, CT 06510 USA
[11] Inst Mexicano Seguro Social, Ctr Med Nacl Siglo 21, Program A Todo Corazon, 330 Cuauhtemoc Ave, Mexico City 06720, DF, Mexico