1. The initial pumping phase will be an in-hospital study, short term study. Patients will be randomly assigned to conventional/conservative treatment or to pump therapy. Within 24 hours of admission patients assigned to pump therapy will be recruited for the study and will begin therapy according to the protocol outlined in the table below. These patients will not be given diuretics unless required to because of shortness of breath with suspected left heart failure. Individualized programs regarding pumping frequency and pump parameters will be set for each patient and will be adjusted during the first few days and maintained throughout the study unless there is a reason to modify them.