RESUMEN
During off-pump coronary artery bypass graft surgery (OPCAB), vigorous displacement and compression of the heart producing significant hemodynamic change are essential for optimal exposure of graft anastomoses. Intraoperative transesophageal echocardiography (TEE) is useful in determining hemodynamic compromise and prompting medical and mechanical support. However, in addition to the loss of contact between the heart and diaphragm during the displacement, swabs or snears underneath the heart interrupt the TEE signal transmission, resulting in a compromised transgastric (TG) TEE view. Therefore, TEE monitoring during OPCAB is usually limited to the mid-esophageal view. The authors placed a saline bag (a surgical glove filled with saline) underneath the heart to facilitate this anterior displacement of the heart, as well as avoid the signal interruption of the TG echocardiographic window. As a result, the optimal heart position with the minimal changes in LV regional wall motion, LV function and mitral regurgitation were found using the TG and other TEE views. The series of velocity-time integral of aortic valvular flow (VTI-Ao) in TG long axis view, in addition to SvO2, were then monitored as a surrogate marker of the cardiac output during a graft construction of the left circumflex artery. It was concluded that the use of a saline bag may be useful in avoiding compromise of the TG TEE view and determine the hemodynamic change using VTI-Ao during cardiac displacement for OPCAB.