Which patient condition is contraindicated for intra-aortic balloon pump (IABP) therapy?

Intra-aortic balloon pump (IABP) therapy is a mechanical circulatory support device used primarily in patients with severe cardiac conditions to improve coronary perfusion and decrease workload on the heart. However, certain conditions can present significant risks when using IABP therapy.

Acute aortic regurgitation is a critical contraindication for the use of IABP because the balloon's inflation during diastole can interfere with the normal regurgitation of blood through the aortic valve. In patients with acute aortic regurgitation, the use of an IABP can exacerbate the volume overload on the left ventricle, leading to worsening of the patient's hemodynamic status. Instead of supporting cardiac function, the IABP may aggravate the condition by increasing diastolic backflow and reducing cardiac output.

In contrast, unstable angina and cardiogenic shock are indications for IABP therapy, as the device can help stabilize these patients through enhanced coronary blood flow and reduced myocardial oxygen demand. When weaning from cardiopulmonary bypass, while caution is always taken, IABP can be used effectively as support during this transitional period.