Albert J. Pfister

Coronary artery bypass without cardiopulmonary bypass

The purpose of this article is twofold: to describe our technique for performing coronary artery bypass grafting without cardiopulmonary bypass (off pump) and to demonstrate that this operation is safe, in terms of mortality and certain indices of morbidity. Very little has been published in regard to off-bypass operations. From 1985 through 1990, 220 patients underwent operation off bypass; 220 on-pump controls were retrospectively matched for number of grafts, left ventricular function, and date of operation. Groups were compared in terms of mortality and ten indicators of morbidity. The same analysis was performed for ten subgroups. We found no statistically significant difference between groups in mortality (off pump, 1.4% [3/220]; on pump, 2.4% [5/220]), which held across all subgroups. Patients undergoing operation off pump required blood far less often (not transfused: off pump, 72.7% [160/220]; on pump, 54.6% [116/220]; p = 0.005 by Fishers exact test), and the low output state occurred statistically less frequently off pump (off pump, 5.5% [12/220]; on-pump, 12.7% [28/220]; p = 0.01 by Fishers exact test). Further research should be directed to which subgroups can be operated on to advantage off pump and which, if any, groups of patients should be confined to on-bypass operations.

Beating heart surgery in octogenarians: perioperative outcome and comparison with younger age groups ☆

BACKGROUNDnOctogenarians have higher morbidity and mortality rates (9% to 16%) after coronary artery bypass grafting with cardiopulmonary bypass, compared with younger patients.nnnMETHODSnWe compared the perioperative outcome and hospital stay after coronary artery bypass grafting without cardiopulmonary bypass (off-pump) from January 1987 to May 1999, among patients older than 80 years (n = 71), patients between 70 and 79 years (n = 228), and patients whose age ranged from 60 to 69 years (n = 296). In comparison with younger patients, more octogenarians were female (51% versus 39% in patients aged 70 to 79 years and 35% in those aged 60 to 69 years, p = 0.04), they had previous myocardial infarction more frequently (48% versus 47% versus 34%, respectively, p = 0.008), and were operated on urgently (69% versus 56% versus 52%, respectively, p = 0.04).nnnRESULTSnPostoperative complications that were significantly higher in octogenarians compared with younger groups included pneumonia (6% in octogenarians versus 2% in patients aged 70 to 79 years and 0% in patients aged 60 to 69 years, p = 0.001) and atrial fibrillation (47% versus 32% versus 21%, respectively, p<0.001). By multivariate logistic regression analysis, age over 80 years was an independent predictor of prolonged hospital stay (odds ratio = 2.7, 95% confidence interval, 1.4 to 5, p<0.001). The in-hospital mortality rate was higher in octogenarians (6% versus 3% for 70 to 79 year-olds and 0.3% for 60 to 69 year-olds, p = 0.006).nnnCONCLUSIONSnWhen appropriately applied in patients older than 80 years, off-pump coronary artery bypass grafting can be done with acceptable postoperative morbidity, mortality, and hospital stay.

Stroke After Coronary Artery Bypass

Background and Purpose— Early postoperative stroke is a serious adverse event after coronary artery bypass grafting (CABG). This study sought to investigate risk factors, prevalence, and prognostic implications of postoperative stroke in patients undergoing CABG. Methods— We investigated the predictors of postoperative stroke (n=333, 2%) in 16 528 consecutive patients who underwent CABG between September 1989 and June 1999 in our institution. Predictors of postoperative stroke were identified by logistic regression analysis. Results— Among the preoperative and postoperative factors, significant correlates of stroke included (1) chronic renal insufficiency (P <0.001), (2) recent myocardial infarction (P =0.01), (3) previous cerebrovascular accident (P <0.001), (4) carotid artery disease (P <0.001), (5) hypertension (P <0.001), (6) diabetes (P =0.001), (7) age >75 years (P =0.008), (8) moderate/severe left ventricular dysfunction (P =0.01), (9) low cardiac output syndrome (P <0.001), and (10) atrial fibrillation (P <0.001). Postoperative stroke was associated with longer postoperative stay (11±4 versus 7±3 days for patients without stroke, P <0.001) and with higher in-hospital mortality (14% versus 2.7% for patients without stroke;P <0.001). Conclusions— Stroke after CABG is associated with high short-term morbidity and mortality. Increased stroke risk can be predicted by preoperative and postoperative clinical factors.

Outcomes for Off-Pump Coronary Artery Bypass Grafting in High-Risk Groups: A Historical Perspective

BACKGROUNDnThe outcomes of off-pump coronary artery bypass (OPCAB) and conventional coronary artery bypass grafting with cardiopulmonary bypass (cCABG) have been compared in detail. Similarly, several reports have examined outcomes of high-risk subsets of patients in OPCAB as a selection strategy for reducing morbidity and mortality compared to cCABG. We undertook a retrospective study comparing outcomes from the early years in our experience of beating-heart surgery in high-risk patients selected for OPCAB compared to low-risk patients having OPCAB. This study was premised on strict selection criteria in an era prior to stabilizing devices and cardiac positioners.nnnMETHODSnA total of 384 patients underwent OPCAB over a 10-year period. Clinical outcomes were compared for 280 low-risk patients and 104 high-risk patients (redo CABG, CABG with simultaneous carotid endarterectomy, or renal insufficiency/failure).nnnRESULTSnThe high-risk group patients were significantly older than the low-risk group patients (64.3 +/- 10.5 years versus 61.5 +/- 11.7 years, respectively, P = .048). The high-risk group also had a greater degree of left ventricular dysfunction (P < .001), a higher incidence of diabetes (P = .046), and a higher proportion of patients with peripheral vascular disease (P = .009). There was no significant difference in the number of grafts created, but there was a statistical difference in the type of graft used. The high-risk group received fewer internal thoracic artery grafts (P = .005) and more saphenous vein grafts (P = .041). The high-risk group had slightly prolonged median lengths of stay in the intensive care unit (2.2 versus 1.4 days, P < .001) and hospital (11 versus 8 days, P < .001) and a higher proportion of patients requiring blood transfusions (48% versus 24%, P < .001), yet there was no significant difference in major adverse outcomes.nnnCONCLUSIONSnIn this retrospective and historical review, OPCAB was found to be equally safe in carefully selected high- and low-risk patients. These results provided for the enthusiasm and innovation to expand the usage of OPCAB in patients with coronary artery disease.

The MIDCAB Operation

For purposes of this discussion, a minimally invasive direct coronary artery bypass (MIDCAB) is considered to be any surgical coronary revascularization performed on the beating heart (“off-pump”) through an incision other than a median sternotomy.