The investigators are interested in determining if there is a meaningful benefit from the use of medications purported to increase the pumping function of the heart (i.e. inotropes) among critically ill patients admitted to the Cardiac Intensive Care Unit (CICU). To do this, the investigators will conduct a multi-centre, double blind, randomized control trial with patients who are deemed to require these medications by their treating physician to one of the two most commonly used agents in Canada (Milrinone or Dobutamine) or placebo. Each patient will be closely monitored by their healthcare team. The dose of medication will be adjusted according to each patients' clinical status. After 12 hours, the participants will move to open label treatment and any continued use of inotropes will be at the discretion of their treating physician.