An extracorporeal blood perfusion system includes a disposable assembly and a control unit having a control interface region. The interface region includes pump assemblies for selective pumping of venous blood, arterial blood, cardioplegia solution, suctioned blood and blood removed from the left ventricle. Valve assemblies control the flow of fluids through the assembly and to/from the patient and sensors monitor various fluid parameters including temperature and pressure within the various fluid circuits. The user interface is a functional screen interface for effecting the operation of the control unit and valve assemblies. The screen interface may be a touch screen having objects that corresponds to the component interface region. The display may be selectively controlled to provide graphic depictions of disposable assembly components with corresponding narrative instructions.