Splanchnic hemodynamics were examined in 22 patients with heart disease, 16 of whom had evidence of ventricular insufficiency at the time of study. The response of the splanchnic vasculature to the exhibition of intravenous digoxin was also studied in nine of these subjects.Ventricular insufficiency was associated with splanchnic vasoconstriction proportional to a generalized increase in peripheral vascularresistance. Splanchnic blood volume was disproportionately increased with respect to total blood volume in patients having visceral congestion with right ventricular failure and combined ventricular failure. A significant relationship between central venous pressure and splanchnic blood volume was demonstrated in these cases. The greater elevation of the former than of the latter suggested the presence of splanchnic venoconstriction.The vascular readjustment to digoxin resulted in a relative intensification of the already existing vasoconstriction of the splanchnic bed as compared to the diffuse systemic vasodilatation which occurred at the same time as the consequence of the inotropic action of the drug: estimated splanchnic blood flow and splanchnic blood volume diminished at a time when systemic flow rose and peripheral vascular resistance decreased. The ultimate distribution of the volume of blood translocated out of the splanchnic bed during this process remains to be determined.