From the Guidelines
The answer is "It increases afterload." Intra-aortic balloon pump (IABP) therapy actually decreases afterload rather than increasing it, as supported by the American Heart Association's scientific statement on the invasive management of acute myocardial infarction complicated by cardiogenic shock 1. IABP works through counterpulsation, where the balloon inflates during diastole to increase coronary perfusion and deflates just before systole to create a vacuum effect that reduces afterload. This reduction in afterload means the heart doesn't have to work as hard to eject blood, which helps improve cardiac output. The other options listed are all true benefits of IABP therapy:
- it does increase cardiac output
- it reduces myocardial ischemia by improving the balance between oxygen supply and demand
- it improves coronary artery perfusion through the diastolic augmentation. The primary goal of IABP therapy is to support the failing heart by simultaneously increasing coronary perfusion while decreasing the workload on the heart, as noted in the IABP-Shock II trial 1.
From the Research
IABP Therapy Benefits
The benefits of Intra-Aortic Balloon Pump (IABP) therapy include:
- It increases cardiac output 2, 3, 4
- It reduces myocardial ischemia 3, 5
- It improves coronary artery perfusion 3, 5
IABP Therapy and Afterload
Regarding afterload, IABP therapy:
- Reduces systolic afterload 2, 3, 5
- Does not increase afterload, as the correct function of IABP is to decrease afterload and increase cardiac output 2, 3, 4, 5
Answer to the Question
Based on the provided evidence, the correct answer is: