Cardiac patch treatment alleviates ischemic cardiomyopathy correlated with unloading pathological stretch and reverting Piezo1/2 expression in left ventricular myocardium

Pathologically elevated mechanical load promotes the adverse remodeling of left ventricle (LV) post myocardial infarction, which results in the progression from ischemic cardiomyopathy to heart failure. Cardiac patches could attenuate adverse LV remodeling by providing mechanical support to infarcted and border zone myocardium. However, the mechanism of the translation from mechanical effects to favorable therapeutic outcome is still not clear. This study aims to strengthen the foundation of the theory of cardiac patch treatment. By transcriptome analysis, we found that the myocardial transcription levels of mechanosensitive ion channel proteins Piezo1 and Piezo2 significantly increased in patients with ischemic cardiomyopathy. In vitro tensile tests with local tissue information and finite element modeling revealed a significant decrease in local strain and mechanical load in rat infarcts and sheep LV. Cardiac function and geometry were preserved compared to non-treated control. Further, in LV myocardium of the patch-treated group, MI induced expression levels of Piezo1/2 were significantly reverted to the similar levels of the control group, indicating that Piezo1/2 are key contributors as mechanosensor which initiated the signaling cascade and translated the beneficial mechanical support to therapeutic effects. These findings demonstrated the potential of cardiac patches in treating ICM patients with remodeling risks, and could provide guidance for improvement in next generation of patch devices. Overall design: Comparative gene expression profiling analysis of RNA-seq data for heart of sham, MI and patch rats