%0 Journal Article %T Left Ventricular Unloading Using Intra-Aortic Entrainment Pumping Before Reperfusion Reduces Post-AMI Infarct Size. %A Fudim M %A Konecny F %A Heuring JJ %A Durst CA %A Fain ES %A Patel MR %J J Card Fail %V 0 %N 0 %D 2024 Aug 13 %M 39147311 %F 6.592 %R 10.1016/j.cardfail.2024.07.022 %X BACKGROUND: Anterior myocardial infarction standard of care prioritizes swift coronary reperfusion. Recent studies show left ventricular (LV) unloading with transvalvular axial-flow pumps for 30 minutes before reperfusion (versus immediate reperfusion) reduces 28-day infarct size. Intra-aortic entrainment pumping, using hardware located away from the heart to provide support throughout the cardiac cycle, reduce effective systemic vascular resistance, and augment visceral blood flow and pressure, may reproduce this benefit with reduced risk. This study characterized hemodynamic effects of unloading before and during reperfusion using intra-aortic entrainment pumping and investigated whether unloading reduced anterior myocardial infarction (AMI) scar size.
RESULTS: Yorkshire swine were subjected to 90 minutes of left anterior descending artery balloon occlusion and randomly assigned to immediate reperfusion (n=6) versus 30 minutes unloading before reperfusion followed by 120 minutes further unloading (n=7). Unloading was achieved using percutaneous entrainment pumping in the descending aorta. The AMI model matches that used in recent transvalvular pumping studies. Mortality before randomization was 22%. After randomization, mortality was 36% for immediate reperfusion and 0% for unloading. Unloading showed immediate hemodynamic benefit that increased through reperfusion and continued support, leading to distinct differences in cardiac function between groups after 30 minutes of reperfusion. Unloading increased stroke volume and cardiac efficiency at this timepoint relative to pre-occlusion baseline and reduced 28-day LV scar size by 37-45%.
CONCLUSIONS: We present the first preclinical data showing extra-cardiac LV unloading before coronary reperfusion using intra-aortic entrainment pumping decreases 28-day infarct size. Extra-cardiac unloading to reduce LV scar size may provide an alternative to transvalvular pumping with potential advantages including reduced risk.