[1] Univ Gregorio Maranon, Gen Hosp, Dept Cardiol, Madrid 28007, Spain
[2] Fac Med Badajoz, Dept Human Anat & Cell Biol, Badajoz, Spain
[3] Univ Gregorio Maranon, Gen Hosp, Dept Anesthesiol, Madrid 28007, Spain
[4] Univ Gregorio Maranon, Gen Hosp, Dept Pathol, Madrid 28007, Spain