While 2D echo visualizes the LSVC , it is the color Doppler flow (in blue ) that confirms the flow going away from transducer towards coronary sinus .Please note , if the LSVC shows red flow it indicates the left vertical vein and the flow is from below up .This is supra cardiac TAPVC . It makes immense embryological sense to understand LSVC and and left vertical vein are both same entities only the connections are different .
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Dr.S.Venkatesan MD 
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