L-->R shunt: a serious consequence of TAPVC repair without ligation of vertical vein.

It has been suggested that concomitant ligation of the vertical vein (VV) is not necessary in the repair of total anomalous pulmonary venous connection. The patency of the VV is desirable in the presence of noncompliant left heart chambers that may not be able to accommodate acute increases in pulmonary blood flow, leading to hemodynamic instability after repair. Complete cessation of flow through the previously patent VV has been observed, obviating the need for a second-stage operation. We report 2 infants who were operated using this strategy, in which the VV continued to function as a conduit for a significant left to right shunt.