Percutaneous carbon dioxide mist treatment has protective effects in experimental myocardial infarction

Percutaneous treatment with carbon dioxide (CO2) mist, CO2 gas dissolved in water, contributes to improved cardiac function after myocardial infarction (MI). In this study, we investigated the effects of repeated pretreatment with CO2 mist on cardiac dysfunction after MI. The CO2 mist was generated by a dry mist production unit. The whole body of rats below the axilla was wrapped in a polyethylene bag, which was sealed and filled with the CO2 mist in the draft cabinet for 30 min daily for 7 days. MI was induced by ligation of the coronary artery in untreated (UT), CO2 gas-pretreated (CG), and CO2 mist-pretreated (CM) rats. The infarct size and the increase in oxidative stress due to MI were significantly smaller in the CM rats than in the UT rats. Furthermore, the expression of inflammation-related genes, such as monocyte chemoattractant protein-1, and fibrosis-related genes, such as transforming growth factor-β1, was significantly suppressed in the CM rats. The CM rats had a better left ventricular ejection fraction than the UT rats 7 days after MI. These parameters in the CG rats were the same as in the UT group. Thus, CO2 mist preparative treatment may be potentially useful for the reduction of MI.