Work

Cardiac unloading via a transvalvular pump prevents arrhythmias following myocardial ischemia / reperfusion by preserving coronary microcirculation and cardiomyocyte nanostructure

Year: 2026

Type: preprint

Abstract: ABSTRACT Cardiac damage in the aftermath of myocardial ischemia / reperfusion (MI/R) compromises both electrical and mechanical function, predisposing patients to arrhythmia and heart failure. Microvascular obstruction (MVO) is increasingly recognized as a sequela of MI/R and a contributor to proarrhythmic cardiac remodeling. While transvalvular unloading (TVU) using a percutaneously delivered pump is garnering appreciation as a means of limiting infarct size and preserving mechanical function following percutaneous coronary intervention, its benefits for arrhythmia prevention remain unclear. We used a porcine model to test the hypothesis that cardiac unloading prior to and through reperfusion mitigates MVO, preserves cardiomyocyte nanostructure, and alleviates arrhythmias following MI/R. Anesthetized domestic swine undergoing acute ischemia (LAD occlusion, 90 mins) and reperfusion (120 mins) were randomized to TVU (n=5) and no treatment (control; n=6) treatments. Thioflavin-S was infused into the mid-LAD to assess coronary microcirculation and quantify MVO. Arrhythmia burden was assessed by in vivo electrocardiography using 3 lead EKG. Cardiac tissues were preserved for histology and optical microscopy studies. Compared to no treatment controls, TVU hearts evidenced significantly reduced infarct area (48 ± 5 % vs. 59 ± 11 % p = 0.03) and MVO (19 ± 4 % vs. 27 ± 5%, p = 0.03) normalized to area at risk and a higher myocardial salvage index (52 ± 5 % vs. 41 ± 11% p = 0.03). Extensive perivascular edema, and neutrophil infiltration observed in controls was markedly reduced in TVU hearts. Confocal microscopy and spatial pattern analysis revealed significantly mitigated disruption of gap junctions and Na V 1.5 dissociation from N-cadherin in TVU hearts compared to controls. Importantly, severity-adjusted arrhythmia burden during reperfusion was significantly lower in TV-P hearts (8±8 vs. 12±5 episodes lasting greater than 5seconds in controls). Our results demonstrate that TVU effectively prevents arrhythmias during reperfusion by preserving coronary microvasculature and cardiomyocyte nanostructure.

Source: bioRxiv (Cold Spring Harbor Laboratory)

DOI: 10.64898/2026.10.14.758560