OBJECTIVE: The purpose of this study was to assess the effect of CO2 on the wall of the Left Internal Thoracic Artery (LITA) and Anterior Interventricular Artery (AIVA) in an experimental model using goats, comparing the immediate effects of the use of CO2 at flow rates of 5 L/min and 10 L/min during 20 minutes, with intermittent flow (every 30 seconds) with and without humidification, simultaneously to the LITA and AIVA. METHODS: Thirty-six male goats were submitted to a surgical procedure. Histological analysis was carried out using the immunoperoxidase reaction to mark the endothelium through the detection of VIII Coagulation Factor. Measurement was made by Quantimet following the Ip scale for vascular injury. RESULTS: Within control groups, with and without humidification, both for AIVA and LITA, there was no endothelial injury. The flow rate of 5 L/min provoked moderately significant endothelial injury of the AIVA without humidification, whereas with humidification the endothelial injury was seen but without statistical significance. The flow rate of 5 L/min, with or without humidification, provoked insignificant endothelial injury at LITA. With a flow rate of 10 L/min, there was highly significant endothelial injury, both for the LITA and AIVA and whether humidified or not. CONCLUSION: In conclusion endothelial injury is flow-dependent with greater injury when using CO2 at a flow rate of 10 L/min and less at 5 L/min. The arteries involved in anastomosis (LITA and AIVA) are both affected, but there is a greater effect on the AIVA.
Coronary disease; Carbon dioxide; Mammary arteries; Endothelium; Animal models
