Reduction of Myocardial Reperfusion Injury by Mechanical Tissue Resuscitation (MTR) using a Bio‐absorbable Patch

Abstract

Myocardial ischemia‐reperfusion injury (MI/R) follows a well defined sequence of early and late myocyte death. Most therapeutic strategies address only one facet of reperfusion injury. Mechanical resuscitation of injured tissue with sub‐atmospheric pressure reestablishes physiologic homeostasis and improves tissue survival. This study explores the use of absorbable material and a mechanical device to achieve resuscitation of myocardial tissue following MI/R.Anesthetized swine were subjected to 80 min of left coronary occlusion and 3 hours of reperfusion. Animals were assigned to either:1) control or 2) treatment with 50mmHg of MTR during reperfusion using a bio‐absorbable patch. Both groups had equivalent (p=0.07) areas at risk (16±1.0% and 13.7±0.6%, respectively). MTR applied directly on the injured myocardium for 180 minutes significantly (p<0.002) reduced infarct size compared to controls: 14.2±3.1% vs 30.2±2.6%. This reduction in infarct size (53%) is comparable to that observed previously when commercially available, non‐absorbable patch materials (55–65% reduction in infarct size) were used.MTR of injured myocardium using an absorbable patch for a defined period of time can reduce tissue death following MI/R. This study reproduces the reduction of infarct size previously observed while utilizing novel, bio‐absorbable materials. The use of degradable material for the application of MTR may allow for longer treatment and better outcomes in the clinical setting while at the same time eliminate the need for a second operation to remove the device. This treatment strategy offers a simple, effective, clinically relevant, non‐pharmacologic approach to reducing injury following MI/R.