Fig. 4. Effects of independently changing outflow resistances in the pulmonary and systemic circulations on flow distributions before and after clamping the pulmonary vein (left atrial inflow) (LAt; A). (B) The left bar in each panel shows the flow distribution during filling of both atria, whereas the right bars show the distribution when right atrial flow was completely abolished. The starting condition is marked by a thicker border; black bars, pulmonary vein; white bars, systemic vein. All values are means ± S.E.M. (N=7); an asterisk indicates a significant effect (P<0.05) from clamping atrial inflow.