<h3>Background</h3> Superior vena cava is usually interrogated intraoperatively by a standard bi-caval view as suggested by American Society of Echocardiography. A modified deep transgastric transesophageal echocardiography view is suggested that will superior interrogation of the superior vena cava intraoperatively. <h3>Objective</h3> Evaluation of a modified deep transgastric imaging of superior vena cava in patients undergoing cardiac surgery. <h3>Methods and material</h3> A modified deep transgastric imaging of superior vena cava was performed in children undergoing cardiac surgery. The deep transgastric interrogation with color Doppler blood flow map showed the venous return pattern. A pulse wave Doppler signal analysis was also feasible. The position of the tip of a central venous catheter tip that was inserted through the internal jugular vein could be seen. An agitated saline contrast injected into the left upper limb could exclude the presence of a left superior vena cava. In patients undergoing a undergoing a bi-directional Glenn shunt, considerable length of superior vena cava was visualized. In a child with a partial anomalous pulmonary venous drainage and a superior sinus venosus ASD, a point of the pulmonary vein joining the superior vena cava could be identified as it was possible to interrogate a considerable length of superior vena cava compared to the standard mid esophageal bi-caval view. The deep transgastric TEE interrogation of superior vena cava revealed a residual gradient in the superior vena cava following a sinus venosus atrial septal defect repair that was corrected at the same sitting. A color Doppler blood flow map across the superior vena cava following removal of a directly inserted venous cannula showed turbulence and a continuous-wave Doppler signal analysis revealed a residual gradient that was immediately corrected by the surgeon in another patient. <h3>Conclusion</h3> In conclusion, the deep transgastric TEE view of the superior vena cava is clinically useful. The doppler alignment is parallel to SVC flow (less than 20 degree) which is superior to bi caval view, where the doppler alignment is almost perpendicular to the flow. The probable difficulties that may be encountered that would interfere with proper visualization are: (i) poor contact of the probe with cephalad aspect of the stomach, (ii) air in the stomach, (iii) use of inadequate contact jelly, and (iv) lack of experience. There is a deep learning curve that can be a practical impediment but once honed, it could be a really useful adjunct to our routine trans-esophageal views.
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