3. Classification TASVD
Type I Type II Type III
IVC to left-sided atrium IVC interruption IVC to accessory chamber (like
coronary sinus)
Type A: Hepatic veins to left-
sided atrium
Type B: Hepatic veins to
other site
4. Zhang ZW, Duan QJ, Gao Z, Ru W, Ying LY. Total anomalous
systemic venous drainage to the left atrium. Ann Thorac Surg
2009;87:1599-601-13
5. Embryology
• Failure of regression of the right valve of systemic venous sinus (sinus
venosus)
• Systemic venous sinus being incorporated into the left atrium
6. Hemodynamic
• Left atrium forms the mixing chamber in the circuit
• Similar to the case of a total anomalous pulmonary venous drainage
• Oxygen saturation is equal in all the chambers
7. Diagnosis
• Echocardiography with agitated saline contrast follow up(caution :air
embolism to brain and coronary)
• CT scan helps confirm drainage of all veins