The intra-aortic balloon pump deflates, what effect does this have?

• A. Inflates, increases afterload
• B. Deflates, reduces afterload
• C. Maintains afterload
• D. Pumps independently

Answer: (B)

An intra-aortic balloon pump works by timing inflation and deflation with the cardiac cycle. Deflating just before systole creates a sudden drop in aortic pressure, so the left ventricle faces less resistance when ejecting blood. This reduces afterload, making it easier for the heart to pump and often improving overall cardiac output and oxygen efficiency. Inflation, in contrast, is timed to diastole to boost coronary perfusion, not to increase afterload. The device isn’t pumping independently and doesn’t maintain afterload; deflation specifically lowers the afterload.