1. Department of Surgery, Verdi Cevallos General Hospital, Portoviejo, Manabí, Ecuador
2. Graduate Department and health science. Technical University of Manabí, Ecuador
3. Department of cardiovascular Surgery Hospicor. Manta. Manabí. Ecuador
4. Graduate Department and health science. Technical University of Manabí, Ecuador.
5. Ásmerp, Metrodial Portoviejo, Portoviejo, Manabí, Ecuador
6. Department of Surgery, Hospital Rodriguez Zambrano, Manta, Manabí, Ecuador