During early deflation of the IABP, what is the consequence of deflation occurring too soon?

During early deflation of the Intra-Aortic Balloon Pump (IABP), if deflation occurs too soon, it can lead to increased afterload. The IABP operates by inflating during diastole to improve coronary perfusion and deflating just before systole to reduce the workload on the heart. If the deflation happens prematurely, the balloon does not appropriately lower the aortic diastolic pressure, mistakenly leading to a situation where the heart has to generate a greater force to eject blood during systole. This increase in resistance the left ventricle must overcome is known as increased afterload.

When afterload increases, it can also elevate myocardial oxygen demand because the heart must work harder to pump against this higher resistance, potentially leading to increased myocardial ischemia if the coronary perfusion is unable to meet this need. Thus, understanding the timing of IABP deflation is critical to the effectiveness of this intervention.