The purpose of the study is to evaluate the safety and effectiveness of the CentriMag ventricular assist system to help patients who have experienced heart failure during surgery and cannot be removed from cardiac bypass.

Inclusion Criteria:

• At least 18 years of age

• Cardiac dysfunction due to failure-to-wean from cardiopulmonary bypass

• Subjects who are on IABP, CPB, ECMO or CPS support prior to evaluation should have the device turned off, if possible, for the purpose of measuring inclusion hemodynamics. However, these devices should not be turned off in patients who would be harmed by interruption of support.

• All subjects must meet the following criteria at the time of enrollment:

• Hemodynamics:

  1. cardiac index ≤ 2.2 L/min/m2
  2. For patients being evaluated for left-sided support (LVAD): PCWP ≥ 18 mmHg or PADP ≥ 18 mmHg or LAP ≥ 18 mmHg
  3. For patients being evaluated for right or biventricular support: CVP ≥ 15 mmHg or RAP ≥ 15 mmHg and RVSWI ≤ 4.1 gm/m2/beat
  4. Enrollment without hemodynamic measurements due to frequent or unpredictable dysrhythmias, unacceptable cardiac function, or hemodynamic instability is allowed.

• Placement of an intra-aortic balloon pump has been attempted unless contraindicated

• All possible measures have been attempted to correct low arterial pH, arterial blood gas abnormalities, electrolytes, hypovolemia, hypervolemia, inadequate cardiac rate, dysrhythmias and residual hypothermia

• Cardiac resuscitation using pharmacologic agents, and epicardial pacing (if appropriate and possible) has been attempted

• Written, signed, and dated informed consent

Exclusion Criteria:

• BUN > 100 mg/dl
• Creatinine > 5 mg/dl
• Presence of any investigational mechanical circulatory support device
• Known history of liver cirrhosis or portal hypertension
• Pulmonary infarction
• Stroke, TIA or history of either condition within the last six months and/or any confirmed, existing neurologic deficits
• Active systemic infection defined as positive blood cultures, core temperature >100.5 degrees, white blood count > 12,500, and treatment with antimicrobials
• Participation in a clinical trial with any experimental treatment within 30 days prior to screening or previous participation in the present study
• Other serious disease(s) limiting life expectancy