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 pre-operative left ventricular function of equal to or less than 30% (LVEF < or =30). The two groups (LVEF < or =30 and LVEF>30) were compared using univariate analysis. Patients in LVEF < or =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 < or =30 and 56% in LVEF>30. Pre-operative predicted risk was 6.4+/-5.5% in LVEF < or =30 and 2.7+/-4.5% in LVEF>30 (P< 0.001). Most (> 95%) of the patients in both groups were elective status, and LVEF < or =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 < or =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 < or =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.
Arom
K V
KV
John Nasseff Heart Hospital, and Minneapolis Heart Institute, St. Paul and Minneapolis, Minneapolis, MN 55407, USA. karom@csa-heart.com
Emery
R W
RW
Flavin
T F
TF
Kshettry
V R
VR
Petersen
R J
RJ
D000368:Aged; D002315:Cardiopulmonary Bypass; D001026:Coronary Artery Bypass / Q000379:methods; D005260:Female; D006801:Humans; D007423:Intra-Aortic Balloon Pumping; D008297:Male; D011183:Postoperative Complications; D012086:Reoperation; D012307:Risk Factors; D013318:Stroke Volume; D018487:Ventricular Dysfunction, Left / Q000503:physiopathology