Background: The aim of this study was to assess the hemodynamic changes during off-pump coronary artery bypass graft (OPCAB) surgery following mobilization and stabilizaiton of the heart in different positions for distal coronary artery anastomoses.

Methods: The study was designed as a prospective clinical trail in between March-June 2002. Thirty patients (22 males, 8 females; mean age 69.5±6.3; range 49 to 81 years) operated on by OPCAB surgery were included in the study. The measurements of mean baseline systemic arterial pressure, right atrial pressure, pulmonary capillary wedge pressure, and cardiac index were compared with those that recorded during the mobilization and stabilization of the heart together with ST segment changes and cardiac specific enzyme analysis.

Results: The cardiac index drop was statistically significant in all territories while the mean systemic arterial pressure dropped in the left anterior descending and the posterior descending artery territories. The right atrial pressure increased 70% while performing the circumflex and the posterior descending artery anastomosis. Pulmonary capillary wedge pressure increased 13% in LAD and 39% in cirtumflex territories. No significant ST segment changes and cardiac specific enzyme rise was observed.

Conclusion: Significant hemodynamic changes can be seen during OPCAB surgery that can effect the whole course of the operation. A surgeon experienced in off pump surgery can overcome the problems caused by hemodynamic changes. Patient selection and certain manoveurs during OPCAB are important aspects that surgeons should be familiar with.

Keywords : Off pump coronary artery bypass surgery; hemodynamics; ischemia