Evolution of right ventricular performance after CABG.

34 patients scheduled for coronary artery bypass graft (CABG) surgery were studied during postoperative period. Right ventricular performance was specially performed with use of cardiac output computer REF-1 Edwards Lab., before Anaesthesia (T1) and at 6 investigation times after surgery during and after mechanical ventilation. The sixth first postoperative hours were marked by a decrease of cardiac index (2.56 +/- 0.4 to 2.41 +/- 0.41.mn-1.m2) and right Ventricular Ejection Fraction (RVEF) (0.48 +/- 0.07 to 0.37 +/- 0.09). The second period was the weaning period with a further drop of RVEF (0.43 +/- 0.1 to 0.36 +/- 0.07) without change in cardiac index (2.80 +/- 0.51.mn-1.m2, suggesting a ventricular post-operative and weaning depression, as previously described for the left ventricle. In addition, postoperative tachycardia (Heart rate = 59 +/- 9 at T1 to 95 +/- 14 at T7) may contribute to myocardial ischemia.