OPCAB surgery: a critical review of two different categories of pre-operative ejection fraction

Objective: Literature review found little information on off-pump coronary artery bypass (OPCAB) procedure in patients with poor left ventricular function and there was no information comparing the low EF and normal EF patients undergoing OPCAB procedure. Methods: Between 1/1/1998 and 6/30/1999, 387patients had surgery performed utilizing the off-pump technique and 45 of these patients had preoperative left ventricular function of equal to or less than 30% (LVEF less than or equal to 30). The two groups (LVEF less than or equal to 30 and LVEF >30) were compared using univariate analysis. Patients in LVEF less than or equal to 30 were older and more female gender. LVEF <30 had more NYHA class IV patients (64 vs. 50%) and more symptoms related to depressed left ventricular function. The mean pre-operative left ventricular function was 25% in LVEF <less than or equal to>30 and 56% in LVEF >30. Pre-operative predicted risk was 6.4 +/-5.5% in LVEF less than or equal to 30 add 2.7 +/-4.5% in LVEF >30 (P<0.001). Most (>95%) of the patients in both groups were elective status, and LVEF less than or equal to 30 patients had increased incidence of redo (11 vs. 6%, P=0.2). In LVEF >30, 84% of the patients had stable angina while only 69% in LVEF less than or equal to 30 (P=0.009). Results: Intra-operatively no significant differences were measured in number of grafts per patient (2.7 vs. 2.8), amount of blood loss, peak CK-MB, skin-to-skin time, or OR time. Patients with LVEF less than or equal to 30 have more frequent utilization IABP during pre, intra and post-operative period. The statistical analysis yields no significance in post-operative major neurological deficit between these two groups; and are comparative to the nationally reported incidence of neurological deficit for on-pump patients. The operative mortality in the low EF group was 4.4 and 1.8% in LVEF >30 group (P=0.23). Conclusions: Given the clinical presentation of the low EF group, higher prediction risk, longer pre-operative stay, and length of ventilation (24 vs. 8 h P=0.12) a longer surgery to discharge stay (8 vs. 6 days, P=0.02) is anticipated. Short-term clinical outcomes for both groups of OPCAB patients encouraged us to continue to offer this approach to this broad base of patient population. (C) 2001 Elsevier Science B.V. All rights reserved.