Related Experiment Video
Updated: Jun 17, 2026
The Intra-Aortic Balloon Pump
Published on: February 5, 2021
How much of the intraaortic balloon volume is displaced toward the coronary circulation?
Christina Kolyva1, George M Pantalos, John R Pepper
1Brunel Institute for Bioengineering, Brunel University, Middlesex, United Kingdom.
Insights
Intra-aortic balloon pumps displace a small volume of blood toward the heart, with a minor portion reaching the coronary arteries. This volume, though small, significantly augments baseline coronary flow.
Area of Science:
- Cardiovascular Physiology
- Biomedical Engineering
Background:
- Intra-aortic balloon pumps (IABP) are crucial for hemodynamic support.
- A key benefit of IABP is coronary flow augmentation.
- Understanding blood volume displacement is vital for optimizing IABP therapy.
Purpose of the Study:
- To quantify blood volume displaced toward the aortic root (V(root)) in patients.
- To measure blood volume perfusing the coronary circulation (V(cor)) in vitro.
- To assess the impact of IABP assistance frequencies (1:1 and 1:2) on these volumes.
Main Methods:
- V(root) was measured in 10 patients by integrating aortic root flow signals during IABP inflation.
- In vitro experiments used a mock circulation system with a silicone aorta.
- Flow measurements in the mock system determined V(cor) and V(tip) distribution during 1:1 and 1:2 IABP support.
Main Results:
- In patients, V(root) was 6.4% (1:1 assist) and 10.0% (1:2 assist) of IABP volume.
- In vitro, V(cor) was measured at 3.7% and 3.8% with a simulated heart.
- In vitro, V(tip) distribution varied, with more volume stored in the aortic wall when the artificial heart was inactive.
Conclusions:
- The blood volume displaced to the coronary circulation by IABP is a small percentage of the nominal IABP volume.
- Despite being a small percentage, this volume represents a significant increase in baseline coronary flow.
- Findings highlight the mechanism of IABP-mediated coronary augmentation.
Objective:
During intraaortic balloon inflation, blood volume is displaced toward the heart (V(tip)), traveling retrograde in the descending aorta, passing by the arch vessels, reaching the aortic root (V(root)), and eventually perfusing the coronary circulation (V(cor)). V(cor) leads to coronary flow augmentation, one of the main benefits of the intraaortic balloon pump. The aim of this study was to assess V(root) and V(cor) in vivo and in vitro, respectively.
Methods:
During intraaortic balloon inflation, V(root) was obtained by integrating over time the aortic root flow signals measured in 10 patients with intraaortic balloon assistance frequencies of 1:1 and 1:2. In a mock circulation system, flow measurements were recorded simultaneously upstream of the intraaortic balloon tip and at each of the arch and coronary branches of a silicone aorta during 1:1 and 1:2 intraaortic balloon support. Integration over time of the flow signals during inflation yielded V(cor) and the distribution of V(tip).
Results:
In patients, V(root) was 6.4% +/- 4.8% of the intraaortic balloon volume during 1:1 assistance and 10.0% +/- 5.0% during 1:2 assistance. In vitro and with an artificial heart simulating the native heart, V(cor) was smaller, 3.7% and 3.8%, respectively. The distribution of V(tip) in vitro varied, with less volume displaced toward the arch and coronary branches and more volume stored in the compliant aortic wall when the artificial heart was not operating.
Conclusion:
The blood volume displaced toward the coronary circulation as the result of intraaortic balloon inflation is a small percentage of the nominal intraaortic balloon volume. Although small, this percentage is still a significant fraction of baseline coronary flow.
