Key result
Application of intra-aortic balloon pumping during acute mitral regurgitation raised average cardiac output by 31% (P=0.012) and reduced average mitral regurgitation by 7.5% (P=0.025).
Why the study?
Does intra-aortic balloon pumping improve hemodynamics in an animal model of cardiogenic shock induced by acute mitral regurgitation?
Does intra-aortic balloon pumping improve hemodynamics in an animal model of cardiogenic shock induced by acute mitral regurgitation?
Effect estimate: -7.5%
p-value: p=0.025
In an animal model of acute mitral regurgitation, IABP lowers aortic impedance, reducing regurgitant fraction and increasing forward cardiac output without altering intrinsic left ventricular function.
Hypothesis-generating for IABP in acute MR shock models; leaves open translation to human cardiogenic shock.
Acute mitral regurgitation (MR) is present in 10% of patients presenting with cardiogenic shock. To stabilize these patients, intra-aortic balloon pumping (IABP) is recommended, but the mechanism of IABP support in these patients is unknown. This animal study was designed to describe the hemodynamic effect of intra-aortic balloon pumping during cardiogenic shock induced by acute MR. In eight calves, left ventricular pressure-volume loops, aortic and left atrial pressure, and aortic, carotid artery, and coronary blood flow were recorded. Acute MR (range 36%-79%) was created by placing a metal cage in the mitral valve. Hemodynamic data was obtained at control, during acute MR, and during acute MR with 1:1 IABP support. Acute MR caused a decrease in cardiac output (-32%, P = 0.018), blood pressure, and carotid artery flow, whereas left ventricular output (+127%, P = 0.018), end-diastolic volume, and left atrial pressure all significantly increased. Stroke work, ejection fraction, and coronary blood flow were not significantly changed, and no signs of ischemia were seen on the ECG. The IABP raised average cardiac output by 31% (P = 0.012) and significantly raised blood pressure and flow to the brain while decreasing systemic vascular resistance. Left ventricular function and mean coronary blood flow did not change, but diastolic coronary flow became more important as shown by the increase in diastolic fraction from 64% to 95%. (P = 0.028). Average MR dropped by 7.5% (P = 0.025). In conclusion, application of the IABP during acute MR lowers aortic impedance, resulting in less MR and more output toward the aorta without changing left ventricular function.
No takes yet. Share an insight, caveat, or question.
Dekker et al. (2003) studied Cardiogenic shock induced by acute mitral regurgitation (n=8). Intra-aortic balloon pumping (IABP) vs. Control (acute MR without IABP) was evaluated on Average mitral regurgitation (-7.5%, p=0.025). Application of intra-aortic balloon pumping during acute mitral regurgitation raised average cardiac output by 31% (P=0.012) and reduced average mitral regurgitation by 7.5% (P=0.025).
Synapse has enriched 5 closely related papers on similar clinical questions. Consider them for comparative context: