BACKGROUND: This study examined the effect of chronic preoperative ACEI treatment on hemodynamics and the amount of vasoconstrictor used to maintain mean arterial pressure (MAP) during off-pump coronary artery bypass surgery (OPCAB)

METHODS: Sixty patients undergoing OPCAB were divided into two groups: ACEI group, in which patients were treated with ACEI preoperatively (n = 30) and control group, in which patients were not treated with ACEI preoperatively (n = 30). Norepinephrine was infused when MAP decreased below 70 mmHg during operation. Hemodynamic variables and amount of norepinephrine infused were obtained during pericardiotomy and during the anastomosis of each coronary artery including left anterior descending artery (LAD), obtuse marginal artery (OM) of left circumflex coronary artery, and posterior descending artery (PDA) of right coronary artery.

RESULTS: During LAD, OM, and PDA anastomosis, cardiac index and mixed venous oxygen saturation were decreased and central venous pressure and systemic vascular resistance index were increased significantly in both group. There was no significant difference in hemodynamic variables, including MAP, between two groups during all study period. During OM anastomosis, amount of norepinephrine infused to maintain MAP was significantly greater in ACEI group than in control group

CONCLUSIONS: Preoperative treatment with ACEI significantly increased amount of vasoconstrictor used to maintain target MAP during OM anastomosis, which has been known as hemodynamically unstable period during OPCAB, and cautious management is required to maintain MAP.