Totally arterial off-pump vs. on-pump coronary revascularization: comparison of early outcome

Our objective was to assess differences in early outcome after completely arterial myocardial revascularization with (on-pump coronary artery bypass grafting or ONCAB) or without cardiopulmonary bypass (off-pump coronary artery bypass grafting or OPCAB). Fifty-eight OPCAB and 91 ONCAB patients receiving exclusively arterial grafts were analyzed. OPCAB patients had more single-vessel (P<0.0001), less triple-vessel (P<0.0001) or left main disease (P=0.0021), higher angina class (P=0.003), more unstable angina (P<0.0001) and previous percutaneous transluminal coronary angioplasty (PTCA; P<0.0001), but similar EuroScores (P=n.s.). ONCAB was associated with longer operation time (P=0.0001) and more anastomoses/patient (P<0.0001). Internal thoracic artery (ITA) use was identical, whereas single left ITA use (P<0.0001) and left ITA jump anastomoses (P<0.0001) were more frequent in OPCAB. Radial artery (RA) use (P<0.0001) and RA jump anastomoses (P<0.0001) were more frequent in ONCAB. Complication rates were similar concerning mortality, arrhythmias, cerebro-vascular accidents (CVA), and renal failure with shorter ventilatory support (P<0.0001) and a trend towards less perioperative myocardial infarction (PMI) (P=0.12) and low output (P=0.089), and more respiratory complications (P=0.056) after OPCAB. Arterial OPCAB patients have less extensive CAD, but more severe symptoms. Early outcome is similar concerning mortality, arrhythmias, CVA, renal failure, or intensive care unit and hospital stay, but with shorter ventilatory support and a trend towards lower PMI and low output, and higher respiratory complication rates after OPCAB.     

Reduced strokes in the elderly: the benefits of untouched aorta off-pump coronary surgery

BACKGROUND: Avoiding aortic manipulation during off-pump coronary artery bypass (OPCAB) reduces the risk for atheroembolic complications and may, thus, benefit elderly patients who are prone to atherosclerotic aortic involvement. METHODS: During a period of 18 months (2000-2002), 160 consecutive OPCAB patients older than 75 years were evaluated. One hundred and three patients undergoing clampless OPCAB were compared to 57 patients in whom side clamps were applied. Clampless revascularization was achieved by in situ or T-graft arterial configurations. RESULTS: Mean age was older (79.3 years vs 78.2, p = 0.049) and the prevalence (43% vs 7%, p < 0.0001) and severity of aortic disease was higher in the clampless group. The main conduits used were bilateral skeletonized internal thoracic artery (47%) and radial arteries (42%). More grafts were performed in the side-clamp group (2.5 +/- 0.5 vs 2.3 +/- 0.6, p = 0.023), however, revascularization of the postero-lateral territory was comparable. While early mortality (2.9% vs 7%, p = >or=0.05), perioperative myocardial infarction (3% vs 5%, p = >or=0.05), and sternal infections (none) were similar, the incidence of major neurological complications (0% vs 5.3%, p = 0.044) and the combined outcome of stroke or mortality (3% vs 12%, p = 0.035) were lower in the clampless group. Multivariate analysis identified side clamping as a predictor for the occurrence of stroke or mortality (OR, 6.28, CL 1.39-28.4, p = 0.017), increasing this risk by sixfold. CONCLUSIONS: Clampless OPCAB is associated with reproducible neurological benefit. Improved neurological outcome may be conferred irrespective of the method of aortic screening in patients 75 years or older. The use of arterial conduits for this purpose is feasible despite the patients' advanced years.     

Bilateral skeletonized internal thoracic artery graftings in off-pump coronary artery bypass: early result of Y versus in situ grafts

BACKGROUND: Use of bilateral skeletonized internal thoracic arteries (ITAs) in off-pump coronary artery bypass (OPCAB) retains several advantages that may eventually result in better patient outcomes. We compared the early results of OPCAB using bilateral ITAs as Y grafts with results of OPCAB using bilateral ITAs as in situ grafts. METHODS: A total of 223 consecutive patients who underwent OPCAB using bilateral skeletonized ITAs as Y grafts (group I, n = 113) or in situ grafts (group II, n = 110) were studied. RESULTS: Both the number of distal anastomoses per patient and the number of distal anastomoses per bilateral ITA were higher in group I (3.5 +/- 1.0 and 2.9 +/- 0.7) than in group II (3.0 +/- 0.7 and 2.4 +/- 0.5) (p < 0.01). Hospital mortality was 1.8% (2/113) in group I and 0.9% (1/110) in group II (p = ns). There were no differences in postoperative complications including atrial fibrillation (13.3% vs 10.9%), perioperative myocardial infarction (0.9% vs 2.7%), mediastinitis (0.9% vs 1.8%), and hypoperfusion syndrome (0.9% vs 0%) between groups I and II (p = ns). Postoperative coronary angiographies performed in 110 patients in group I and 108 patients in group II showed 99.0% (382/386) overall patency and 99.4% (319/321) patency for distal anastomoses using ITAs in group I, and 98.1% (312/318) overall patency and 98.1% (258/263) patency for distal anastomoses using ITA in group II. There were no significant differences in graft patency rates between the two groups (p = ns). CONCLUSIONS: Our results demonstrate that OPCAB using bilateral skeletonized ITAs is technically feasible, with excellent graft patency. Using bilateral skeletonized ITAs as Y grafts increases the number of distal anastomoses that can be performed and does not cause additional postoperative morbidity.     

Conversion in off-pump coronary artery bypass grafting: an analysis of predictors and outcomes

BACKGROUND: The incidence, predictive factors, and outcomes related to conversion from off-pump coronary artery bypass (OPCAB) to on-pump coronary artery bypass grafting (ONCAB) have not been well defined. We sought to determine the incidence of conversion, predictive factors, and any associated adverse consequences. METHODS: From January 2000 through June 2002, 1,644 patients underwent nonemergent OPCAB with 61 patients requiring conversion from OPCAB to ONCAB. These groups were retrospectively compared by univariate and multivariate regression analysis. The converted group was then computer matched 1:3, to a cohort of ONCAB patients to determine differences in outcomes. RESULTS: The overall conversion rate was 3.71%. Converted patients compared with a computer-matched ONCAB patients had a higher incidence of operative mortality (18.0% versus 2.7%, p < 0.001). Urgently converted patients had a higher incidence of postoperative cardiac arrest (25% versus 1.1%, p < 0.001), multisystem organ failure (10.7% versus 0.6%, p < 0.001), vascular complications (7.1% versus 1.1%, p = 0.03), and perioperative myocardial infarction (10.7% versus 1.1%, p = 0.02). Predictive factors for conversion were surgeon early in OPCAB experience (odds ratio [OR] 4.4), previous CABG (OR 2.8), and congestive heart failure (OR 2.0). The need for urgent-emergent conversion was highly predictive for operative mortality (OR 7.3) compared with elective conversion. CONCLUSIONS: Patients undergoing urgent-emergent but not elective conversion from OPCAB to ONCAB had a significantly higher risk of mortality and morbidity compared with patients whose procedure was initially ONCAB. Variables predictive of conversion included previous CABG, congestive heart failure, and surgeons early in OPCAB experience.     

Warm ischemia provokes inflammation and regional hypercoagulability within the heart during off-pump coronary artery bypass: a possible target for serine protease inhibition.

OBJECTIVE: Accumulating evidence suggests that a hypercoagulable state influences early graft failure after off-pump coronary artery bypass (OPCAB). We hypothesized that regional myocardial ischemia caused by obligatory periods of coronary occlusion during OPCAB is an important trigger for this prothrombotic state. METHODS: Using a series of biomarkers, 60 consecutive patients undergoing OPCAB were monitored for myocardial injury (myoglobin), inflammation (TNF-alpha, IL-8) and thrombosis (thrombin generation-F1.2, contact activation pathway-FXII-a, platelet derived microparticles-via flow cytometry). The transcardiac gradients of these markers were determined by assaying both arterial and coronary sinus blood just after protamine administration. Intramyocardial pH was monitored continuously during coronary occlusion in a subset (N=30 grafts, 11 patients). The influence of management strategies affecting hemostasis (e.g. antiplatelet therapy, anti-fibrinolytics, peak activated clotting time (ACT) during heparinization) was analyzed. RESULTS: Ischemic injury, depicted by the transcardiac myoglobin gradient, significantly correlated with intramyocardial acidosis during coronary occlusion (R=0.96, p<0.0001) and predicted the transcardiac gradients of TNF-alpha (R=0.83, p<0.001) and F1.2 (R=0.72, p<0.0001). Transcardiac F1.2 strongly correlated with TNF-alpha (R=0.73, p=0.01) and IL-8 (R=0.51, p=0.02). Patients receiving aprotinin (N=20) showed significantly lower transcardiac gradients for myoglobin (4.1+/-7.5% vs 72.9+/-108.8% change, p=0.002), F1.2 (31+/-37% vs 89+/-149%, p=0.03), FXII-a (2.6+/-4.1% vs 19.2+/-34%, p=0.04) and microparticles (7+/-3.9% vs 12.9+/-8%, p=0.01). CONCLUSIONS: Strong correlations between myocardial ischemia and the transcardiac gradients of markers for inflammation and thrombosis suggest that even brief episodes of coronary occlusion in the beating heart may have pathophysiologic consequences. Aprotinin, but not other factors that influence the coagulation system, appears to mitigate this process during OPCAB.     

Coronary artery bypass grafting: an off-pump versus on-pump review

There has been a proliferation in the number of coronary artery bypass grafts (CABG) being performed without the use of cardiopulmonary bypass (CPB). However, the benefits of off-pump coronary artery grafting (OPCAB) are still being determined. The aim of this retrospective review was to compare the perioperative outcomes of CPB patients with OPCAB patients and to identify the patients most likely to benefit from the off-pump procedure. We reviewed the perioperative data of all isolated CABG patients at two metropolitan hospitals for the period of August 2000 to September 2001. The two groups (OPCAB vs. CPB) were further divided into subgroups identifying patients by their predicted mortality (higher-risk and lower-risk) and the number of distal graft anastomoses received (1, 2, 3, 4, or 5). A p value less than .05 was considered significant. Out of the total of 882 patients, 46.2% were OPCAB cases. Both CPB and OPCAB groups were similar in terms of demographics and predicted risk of mortality. Intraoperatively, OPCAB patients had fewer distal graft anastomoses (2.4 +/- 1.0 vs. 3.2 +/- 1.0, p < .001). Postoperatively, patients in the OPCAB group had less chest drainage (889 +/- 588 vs. 989 +/- 662 mls, p < .001), sustained fewer strokes (0.2 vs. 1.9%, p < .05), were transfused less (15.4 vs. 32.5%, p < .001) and were discharged earlier (7.3 +/- 5.6 vs. 8.5 +/- 9.1 days, p < .05). For higher-risk patients, OPCAB was associated with fewer reoperations for bleeding (1.3 vs. 6.4%, p < .05), a lower stroke rate (0 vs. 3.2%, p < .05), and a trend toward lower mortality (7.1 vs. 15.1%, p = .08). However, lower-risk OPCAB patients' stroke incidences (0.5% OPCAB group vs. 1.4% CPB group), and mortality rates (0.5 vs. 0.5%) were similar. Comparisons by number of grafts performed revealed that only the single-grafted OPCAB patients had statistically fewer postoperative complications, reduced chest drainage, and a shorter intensive care stay. Differences between either operation groups in transfusion rates were only statistically significant for the one to three grafted patients, while postoperative stays were similar for patients having four grafts. These results suggest that OPCAB is associated with a reduction in mortality and morbidity, particularly within the higher-risk patients. However, the benefits of OPCAB diminished with an increasing number of distal anastomoses performed.     

Risk-adjusted analysis of long-term outcomes after on- versus off-pump coronary artery bypass grafting

 Open in a separate windowOBJECTIVESRecent data suggested that off-pump coronary artery bypass (OPCAB) may carry a higher risk for mortality in the long term when compared to on-pump coronary artery bypass (ONCAB). We, therefore, compared long-term survival and morbidity in patients undergoing ONCAB versus OPCAB in a large single-centre cohort.METHODSA total of 8981 patients undergoing isolated elective/urgent coronary artery bypass grafting between January 2009 and December 2019 were analysed. Patients were stratified into 2 groups (OPCAB n = 6649/ONCAB n = 2332). The primary end point was all-cause mortality. Secondary endpoints included repeat revascularization, stroke and myocardial infarction. To adjust for potential selection bias, 1:1 nearest neighbour propensity score (PS) matching was performed resulting in 1857 matched pairs. Moreover, sensitivity analysis was applied in the entire study cohort using multivariable- and PS-adjusted Cox regression analysis.RESULTSIn the PS-matched cohort, 10-year mortality was similar between study groups [OPCAB 36.4% vs ONCAB 35.8%: hazard ratio (HR) 0.99, 95% confidence interval (CI) 0.87–1.12; P = 0.84]. While 10-year outcomes of secondary endpoints did not differ significantly, risk of stroke (OPCAB 1.50% vs ONCAB 2.8%: HR 0.51, 95% CI 0.32–0.83; P = 0.006) and mortality (OPCAB 3.1% vs ONCAB 4.8%: HR 0.65, 95% CI 0.47–0.91; P = 0.011) at 1 year was lower in the OPCAB group. In the multivariable- and the PS-adjusted model, mortality at 10 years was not significantly different (OPCAB 34.1% vs ONCAB 35.7%: HR 0.97, 95% CI 0.87–1.08; P = 0.59 and HR 1.01, 95% CI 0.90–1.13; P = 0.91, respectively).CONCLUSIONSData do not provide evidence that elective/urgent OPCAB is associated with significantly higher risks of mortality, repeat revascularization, or myocardial infarction during late follow-up when compared to ONCAB. Patients undergoing OPCAB may benefit from reduced risks of stroke and mortality within the first year postoperatively.     

Off-pump multivessel coronary artery surgery in high-risk patients

BACKGROUND: Coronary artery bypass surgery on cardiopulmonary bypass is associated with significant morbidity and mortality, which may be more marked in high-risk patients. We evaluated our results of off-pump coronary artery bypass (OPCAB) in high-risk patients with multivessel coronary artery disease and compared them with results in similar patients who underwent operation on cardiopulmonary bypass. METHODS: A total of 1,075 patients who underwent OPCAB between October 1996 and June 2001 and who had one or more of the following risk factors were included in the study: poor left ventricular function (EF < or = 30%), advanced age (> 70 years), left main stenosis, acute myocardial infarction, and redo coronary artery surgery. These patients were compared with 2,312 similar patients who underwent coronary artery bypass grafting on cardiopulmonary bypass during the same period. Preoperative risk factors, intraoperative variables, and postoperative results were analyzed and compared between two groups. RESULTS: The average number of grafts was 3.0 +/- 0.4 and 3.2 +/- 0.3 in the off-pump (OPCAB) and on-pump (CCAB) groups, respectively. Hospital mortality was 3.2% and 4.5% in OPCAB and CCAB groups respectively (p = 0.109). Perioperative myocardial infarction, requirement of inotropic agents, stroke, and renal dysfunction were comparable in two groups. Intubation time (19 +/- 5 vs 24 +/- 6 hours, p < 0.001), mean blood loss (362 +/- 53 vs 580 +/- 66 mL, p < 0.001), atrial fibrillation (14.3 vs 19.7%, p < 0.001), and prolonged ventilation (4.6 vs 7.6%, p = 0.002) were less in OPCAB group. Intensive care unit stay (20 +/- 8 hours) and hospital stay (6 +/- 3 days) were significantly less in the OPCAB group (p < 0.001). CONCLUSIONS: Off-pump coronary artery surgery can be safely performed in high-risk patients with multivessel coronary artery disease. Operative mortality is comparable to that associated with on-pump surgery, and avoidance of cardiopulmonary bypass is associated with reduced postoperative morbidity in these patients.     

Pulmonary outcomes of off-pump vs on-pump coronary artery bypass grafting: a prospective randomised controlled study

Background

Coronary Artery Bypass Grafting (CABG) surgery performed on Cardio- Pulmonary Bypass (CPB) may cause pulmonary dysfunction. Off Pump CABG (OPCAB) requires more expertise, but is presumed to reduce pulmonary morbidity as it alleviates the ill effects of CPB. Various studies have conflicting reports of pulmonary dysfunction with both techniques.

Methods

A single blind, prospective, randomised controlled study to detect differences in early pulmonary outcomes measured by pre-operative and post-operative pulmonary function tests in On-Pump Coronary Artery Bypass (ONCAB) vs OPCAB surgery for triple vessel disease. Patients with preoperative pulmonary dysfunction were excluded.

Results

The preoperative Pulmonary Function Test (PFT) parameters in both groups were statistically similar. Postoperative PFT in both groups (ONCAB vs OPCAB) showed reduction although statistically insignificant [FVC-58.7+/?17.5 vs 58.1+/?18.9, p?=?0.87; FEV1- 61.7+/?16.9 vs 60.28+/? 18.3, p?=?0.74; FEV1/FVC- 110+/?13.7 vs 107.4+/?11.79, p?=?0.31; PEF- 76.5+/?26.4 vs 61.8+/?22.2, p?=?0.07; F.MEP- 87.31+/?44.3 vs 74.1+/?29.2, p?=?0.28]. There was no clinical impairment in either group and ventilatory requirements were similar (13.9+/?2.6 vs 14.9+/?3.1 h; p?=?0.3).

Conclusions

Early pulmonary outcome is similar for patients without preexisting pulmonary dysfunction and undergoing elective multivessel revascularisation by ONCAB or OPCAB surgery. The hospital stay and ventilatory time were similar in both groups.     

Better ischemic event-free survival after two internal thoracic artery grafts: 13 years of follow-up.

BACKGROUND: We researched our data to determine whether pedicled bilateral internal thoracic artery (BITA) grafting led to better ischemic event-free survival compared to single ITA grafting, at 10 years mean follow-up. METHODS: Retrospectively 249 patients with BITAs with or without additional vein grafts (BITA group) were matched with 233 comparable patients with left ITA and additional vein grafts (LITA group), at a mean follow-up interval of 10 years. RESULTS: At 13 years, 76.2% +/- 5.9% of the BITA and 78.3% +/- 3.8% of the LITA patients were still alive (p = not significant). Death, recurrent angina, new myocardial infarction, or coronary reinterventions occurred more often in LITA (49.4%) than BITA (33.3%) patients (p = 0.0004). The ischemic event-free survival estimates for BITA patients (47.5% +/- 8.4%) was better than for LITA patients (35.4% +/- 5.1%) (p < 0.001). Multivariate analysis showed that BITA was a predictor for ischemic event-free survival (p = 0.0005). CONCLUSIONS: For the decision to use one or two ITAs the positive influence of BITA grafting on ischemic event-free survival is more important than its effect on survival, per se. Compared to the general strategy of BITA grafting, neither total arterial revascularization nor the specific vessels grafted with BITA is relevant for the ischemic event-free survival.     

Off-pump coronary artery bypass

OBJECTIVES: Off-pump coronary artery bypass grafting (CABG) on the beating heart has become popular procedure in cardiac surgery and its initial results appeared favorable. We report our early and mid-term results of off-pump CABG performed at Shin-Tokyo Hospital. METHODS: Medical records of patients undergoing off-pump or conventional on-pump CABG from September 1, 1996, to August 31, 1999 were retrospectively reviewed. Patients underwent off-pump CABG were further classified into 2 groups; MIDCAB (Off-pump CABG for single vessel revascularization via a small skin incision) and OPCAB (off-pump CABG mainly approached via midline sternotomy) group. Their preoperative, perioperative, and follow-up data were collected and analyzed. RESULTS: Among a total of 995 cases of CABG, 194 cases were off-pump CABG (male/female 142/52, mean age 66.9). The mean number of distal anastomoses in off-pump CABG was 1.9 +/- 0.9 (1.0 +/- 0.0 in MIDCAB and 2.3 +/- 0.7 in OPCAB), which was significantly fewer than in on-pump CABG (3.6 +/- 1.1), with p < 0.0001. Intubation time (5.3 +/- 5.7 hours in off-pump CABG vs 13.1 +/- 24.2 hours in on-pump CABG), ICU stay (1.7 +/- 1.1 vs 3.2 +/- 3.0 days), and postoperative hospital stay (14.0 +/- 7.9 vs 18.1 +/- 12.1 days) in off-pump CABG were significantly shorter than in on-pump CABG (p < 0.0001). In the off-pump CABG group, there were no in-hospital deaths and 14 major complications, fewer than in on-pump CABG (8 hospital deaths and 114 major complications). Postoperative angiography before hospital discharge was conducted in 80 patients (41.2%) and showed 2 occlusions, giving a graft patency rate of 98.6% in the off-pump group. During follow-up (0.9 +/- 0.6 year) period, there were 5 non-cardiac deaths and 20 cardiac events in the off-pump group. The actuarial survival rate at 36 months was 94.6% for off-pump CABG, showing no significant difference from the rate for conventional CABG patients (95.2% at 36 month, p = NS) The event-free rate was 84.0% at 36 months in off-pump CABG patients; however, which was less favorable than on-pump CABG patients (88.0% at 36 months, p < 0.05). CONCLUSIONS: Both in-hospital and mid-term results for off-pump CABG patients were acceptable. Isolated CABG can thus be safely performed without cardiopulmonary bypass. Advances in coronary stabilization have contributed to these improved results. The observed long-term cardiac events may be related to incomplete revascularization.     

A prospective randomized study to evaluate the renoprotective action of beating heart coronary surgery in low risk patients.

OBJECTIVES: Cardiopulmonary bypass (CPB) is widely regarded as an important contributor to renal failure, a well recognized complication following coronary artery surgery (coronary artery bypass grafting (CABG)). Anecdotally off-pump coronary surgery (OPCAB) is considered renoprotective. We examine the extent of renal glomerular and tubular injury in low-risk patients undergoing either OPCAB or on-pump coronary artery bypass (ONCAB). METHODS: Forty low-risk patients with normal preoperative cardiac and renal functions awaiting elective CABG were prospectively randomized into those undergoing OPCAB (n=20) and ONCAB (n=20). Glomerular and tubular injury were measured respectively by urinary excretion of microalbumin and retinol binding protein (RBP) indexed to creatinine (Cr). Daily measurements were taken from admission to postoperative day 5. Fluid balance, serum Cr and blood urea were also monitored. RESULTS: No mortality or renal complication were observed. Both groups had similar demographic makeup, Parsonnet score, functional status and extent of coronary revascularization (2.1+/-1.0 vs. 2.5+/-0.7 grafts; P=0.08). Serum Cr and blood urea remained normal in both groups throughout the study. A significant and similar rise in urinary RBP:Cr occurred in both groups peaking on day 1 (3183+/-2534 vs. 4035+/-4079; P=0.43) before reapproximating baseline levels. These trends were also observed with urinary microalbumin:Cr (5.05+/-2.66 vs. 6.77+/-5.76; P=0.22). Group B patients had a significantly more negative fluid balance on postoperative day 2 (-183+/-1118 vs. 637+/-847 ml; P=0.03). CONCLUSIONS: Although renal complication or serum markers of kidney dysfunction were absent, sensitive indicators revealed significant and similar injury to renal tubules and glomeruli following either OPCAB or ONCAB. These results suggest that avoidance of CPB does not offer additional renoprotection to patients at low risk of perioperative renal insult during CABG.     

Low systemic vascular resistance state following off-pump coronary artery bypass grafting

OBJECTIVE: To determine the prevalence, hemodynamic characteristics, and risk factors for low systemic vascular resistance (SVR) state following after off-pump coronary artery bypass (OPCAB). PATIENTS AND METHODS: SVR data could be obtained for 116 OPCAB patients. Low SVR was defined as an indexed systemic vascular resistance (SVRi) of <1,800 dyne x s/cm(5) x m(2) at the end of operation. Hemodynamic data were recorded preoperatively, at the end of operation, just after entering ICU, and the following morning. RESULTS: Low SVR state was noted in 54 of 116 patients (53%). The SVRi values in low-SVR and non-low-SVR patients were 1,406+/-253 and 2,326+/-509 dyne x s/cm(5) x m(2) at the end of operation (p<0.0001). Increased CI level, decreased MAP level, but unchanged CVP level was observed postoperatively in the low-SVR patients. The increase in CI and decrease in MAP were maximal at the end of operation. Patients with low SVR were more likely to have a higher body mass index (24.5+/-3.6 vs. 22.9+/-2.9; p=0.013) and to be male (82% vs. 62%; p=0.036) than no-low-SVR patients. In low-SVR patients, fluid balance was more positive intraoperatively (3,537+/-1,411 vs. 3,068+/-1,597; p=0.09), but more negative at 6 hours postoperatively (-136+/-978 vs. 234+/-844; p=0.034) and 12 h postoperatively (-282+/-1,321 vs. 268+/-1,238; p=0.024). CONCLUSIONS: Low SVR state, a probable manifestation of systemic inflammatory response (SIRS), is common in patients who have undergone OPCAB. For these patients it is more reasonable to maintain MAP with vasopressors by restoring vascular tone, than by volume loading.     

Propensity score analysis of early and late outcome after redo off-pump and on-pump coronary artery bypass grafting.

BACKGROUND: The purpose of this study was to compare early and late results of redo-CABG with (redo-ONCAB) and without (redo-OPCAB) cardiopulmonary bypass. METHODS: From April 2001 to September 2006 redo-CABG was performed in 110 patients (redo-ONCAB=50 and redo-OPCAB=60). Applying the propensity score, 43 OPCAB patients were matched with 43 ONCAB patients. The mean EuroScore was 5+/-4.7 and 5+/-3.4 for redo-ONCAB and redo-OPCAB, respectively (p=0.5). The number of diseased coronary arteries was 3+/-0.5 and 2+/-0.8 in redo-ONCAB and redo-OPCAB, respectively (p<0.01). RESULTS: Twelve patients underwent OPCAB through anterior thoracotomy while the rest of the patients (n=74) underwent median sternotomy. Mean number of grafts performed was 3+/-0.8 in redo-ONCAB and 2+/-0.6 in redo-OPCAB (p<0.05). The need for postoperative insertion of intra-aortic balloon pump (IABP) was higher (p=0.02) in redo-ONCAB (n=9, 21%) than redo-OPCAB (n=1, 2%). The duration of postoperative ventilation was 55+/-98.7 h for redo-ONCAB and 10+/-12.8h for redo-OPCAB (p=0.008). No differences were found in the incidence of other postoperative complications. The 30-day mortality rate was 6.9% for redo-ONCAB (n=3) and 2.3% redo-OPCAB (n=1; p=NS). Mean follow-up for redo-ONCAB was 30+/-21.3 months (range 0.1-63 months) and that of redo-OPCAB was 37+/-19.2 months (0.1-62.5 months). Actuarial survival at 5 years was 87+/-5.5% for redo-ONCAB and 95+/-3.2% for redo-OPCAB (p=0.17). Event-free survival was 71+/-8.0% for redo-ONCAB and 78+/-7.2% for redo-OPCAB (p=0.32). CONCLUSION: OPCAB is an acceptable strategy in selected patients requiring redo-CABG. Employing a strategy of OPCAB for those patients with 2 or fewer lesions and ONCAB for those with more diffuse disease, redo-OPCAB and redo-ONCAB have similar early and late outcomes.     

Pretreatment with angiotensin-converting enzyme inhibitors attenuates ischemia-reperfusion injury

BACKGROUND: The Heart Outcomes Prevention Evaluation (HOPE) trial demonstrated that ischemic events are decreased in patients receiving angiotensin-converting enzyme (ACE) inhibitors. This study sought to determine whether pretreatment with ACE inhibitors would attentuate ischemic injury during surgical revascularization of ischemic myocardium. METHODS: In a porcine model, the second and third diagonal vessels were occluded for 90 minutes, followed by 45 minutes of cardioplegic arrest, and 180 minutes of reperfusion. Ten pigs received quinapril (20 mg p.o. q.d.) for 7 days prior to surgery; 10 others received no-ACE inhibitors. RESULTS: Quinapril-treated animals required less cardioversions for ventricular arrhythmias (1.58 +/- 0.40 vs 2.77 +/- 0.22; p < 0.05), had higher wall motion scores assessed by two-dimensional echocardiography (4 = normal to -1 = dyskinesia; 2.11 +/- 0.10 vs 1.50 +/- 0.07; p < 0.05), more complete coronary artery endothelial relaxation to bradykinin (45% +/- 3% vs 7% +/- 4%; p < 0.005), and lower infarct size (24.0% +/- 3.0% vs 40.0% +/- 1.7%; p < 0.0001). CONCLUSIONS: ACE inhibition prior to coronary revascularization enhances myocardial protection by decreasing ventricular irritability, improving regional wall motion, lowering infarct size, and preserving endothelial function.     

Early results of complete off-pump coronary revascularization using left internal thoracic artery with composite radial artery

Objective: Off-pump coronary artery bypass (OPCAB) using the left internal thoracic artery (LITA) with a composite radial artery (RA) was employed for arterial revascularization in order to minimize neurological complication. Methods: Sixty-one patients underwent OPCAB using the LITA with a composite RA. Angiography was performed in all patients at two weeks postoperatively. Results: The mean number of distal anastomoses was 3.2±0.4 A Y-composite graft was used in 55 patients, and K-composite graft was used in the other 6 patients. There was no hospital death, no neurological complication nor deep sternal infection Furthermore, there was no episode of perioperative myocardial infarction nor hypoperfusion syndrome. Patients have been angina-free during a mean follow-up period of 1 year. The graft patency of the LITA to the left anterior descending artery (LAD) was 100% (61/61 anastomoses). The RA became occluded in 4 patients, and the patency rate was 95.6% (130/136 anastomoses). String or coronary-coronary bypass resulting from flow competition was observed in the LITA of 6 patients and in the RA of 13 patients. The string of the LITA occurred in the segment distal from the anastomosis with the composite RA. The string or coronary-coronary bypass was observed more often in cases in which the recipient coronary artery had less than 75% stenosis. Conclusion: OPCAB using only the LITA with a composite RA can be successfully and safely performed in patients with multivessel disease. Late postoperative follow-up of the flow competition is necessary to delineate the significance of flow competion.     

Determinants of stroke after coronary artery bypass grafting.

OBJECTIVES: Cerebrovascular accidents (CVA) after CABG are deleterious complications whose prevention remains poorly defined. The aim of this study was to identify the determinants for CVA after CABG. METHODS: Nine thousand nine hundred and sixteen patients underwent CABG at our institution from January 1992 to June 2002. Data were prospectively collected and univariate/multivariate analyses conducted. RESULTS: Two hundred and eight patients (2.1%) suffered perioperative CVA. Univariate analysis showed a higher risk profile in the CVA group including advanced age, depressed percent left ventricular ejection fraction (LVEF), unstable angina, diabetes mellitus (DM), chronic renal failure (CRF), redo surgery, peripheral vascular disease (PVD), previous CVA, and higher Parsonnet score (P<0.001). Furthermore, the CVA group had longer myocardial ischemia (CVA 56.2 +/-40.9 vs. Control 50.4+/-20.9 min, P=0.03) and cardiopulmonary bypass (CPB) times (CVA 87.4+/-30.0 min vs. Control 78.9 +/-25.9 min, P<0.0001), and lower off-pump surgery rate (CVA 1.4% vs. Control 4.7%, P=0.01). Multivariable analysis identified seven preoperative and two perioperative determinants for CVA: LVEF<30% (odds ratio (OR)=2.49), previous CVA (OR=2.15), DM (OR=1.78), redo (OR=1.76), PVD (OR=1.66), CRF (OR=1.55), age (OR=1.03), perioperative intra-aortic balloon pump (OR=1.83), and transfusion rate (OR=1.59). Perioperative mortality was higher in the CVA group (CVA 18.6% vs. Control 2.6%, P<0.0001). CONCLUSIONS: Although occurrence of CVA seems mainly related to preoperative comorbidities, perioperative surgical variables, such as off-pump surgery, myocardial ischemia and cardiopulmonary bypass time, do not seem to independently influence CVA rate after CABG. In this regard CVA prevention should be performed before posing an indication to CABG, and closer evaluation of patients' risk profiles and tailored clinical/surgical strategies for those patients at higher risk for CVA occurrence should be included.     

On-pump versus off-pump coronary artery bypass: independent risk factors and off-pump graft patency.

OBJECTIVE: Current knowledge on off-pump coronary artery bypass (OPCAB) generally stems from single surgeons' experience or from series where OPCABs constituted a minor fraction of coronary operations. The present center decided to venture as far into OPCAB as possible during 1999. The present series thus represents the average surgeon's experience. METHODS: During 1999, 533 patients underwent coronary artery bypass grafting using cardiopulmonary bypass (CPB) in 368 and OPCAB in 165 including the circumflex artery (CX) area in 91. Coronary arteriography was performed before discharge in the first 103 OPCAB patients. RESULTS: The CPB and OPCAB groups differed as regards left ventricular ejection fraction (53+/-13 versus 57+/-11, P < 0.0001) and frequency of triple-vessel or left main stem disease (84 versus 32%, P < 0.0001) but were comparable as regards diabetes (12%), prior myocardial infarct (57%), unstable angina (21%), and previous heart surgery (3%). Using multivariate analyses, 30-day mortality (1.3%), P-creatine kinase myocardial band (CKMB) > 80 microg/l (11.1%), re-sternotomy for bleeding (4.5%) or dehiscense (1.7%), transitory cerebral ischemia and stroke (1.7%), supraventricular tachycardia (27.4%), and hospital stay (mean 8 days) were unrelated to off- versus on-pump surgery as well as to OPCAB in triple-vessel disease. CX branches < or = 1mm, > or = 5 distal anastomoses, prior heart surgery, right coronary artery (RCA) branches < or = 1.5mm, 8-21 days old myocardial infarct, female gender, and preoperative acute arrhythmia (among others) were identified as independent risk factors for mortality or increased CKMB in all 533 patients. The latter five risk factors were reproduced in the OPCAB group isolated. The patency in the 103 OPCABs was 95.3, 91.8, and 85.3% in the left anterior descending artery (LAD), CX, and RCA, respectively. Patency was inversely related to diameter of the grafted vessel in the LAD and CX areas, unlike the RCA area. CONCLUSIONS: The results after beating heart surgery were good also in patients with triple-vessel disease, but specific gains relative to on-pump surgery could not be shown. The independent risk factors in the OPCAB group may indicate relative contraindications for OPCAB grafting.     

Off-pump versus on-pump reoperative CABG via a left thoracotomy for circumflex coronary artery revascularization

OBJECTIVE: Reoperative CABG via a left thoracotomy (RCLT) has become a useful approach for revascularization of the circumflex coronary territory for patients who are at high risk for conventional approach. This study compares the results of RCLT using cardiopulmonary bypass (CPB) with those of a beating heart technique (OPCAB). METHODS: Thirty-two patients who underwent RCLT over the past 10 years were included. Fourteen patients undergoing on-pump RCLT (CPB) were compared to 18 patients undergoing off-pump RCLT (OPCAB). Baseline characteristics of the study groups were similar. Follow-up was 100% complete. A single graft was performed in all patients except one who had two grafts. RESULTS: There were no deaths or perioperative myocardial infarctions in either group. The incidence of atrial fibrillation (CPB: 29% vs. OPCAB: 11%) and the percentage of patients requiring ventilator support longer than 24 hours (21% vs. 6%) was not significantly different between the groups. However, allogeneic blood product utilization (0.9 +/- 1.2 vs. 0.3 +/- 0.7 units, p = 0.04), ICU stay (65 +/- 79 vs. 28 +/- 16 hours, p = 0.04) and total hospital length of stay (8 +/- 4 vs. 5 +/- 1 days, p = 0.001) were significantly lower in the OPCAB group. Average follow-up for the entire cohort was 33 +/- 9.8 months (range 2-102 months). Three-year survival was 74 +/- 9% with 9 deaths (28%) during the follow-up, but only 3 (9%) were cardiac related. Reinterventions were indicated in 6 patients (19%) (PTCA; 5, CABG: 1). Follow-up was longer for the CPB group (51 +/- 33 vs. 19.5 +/- 14 months, p = 0.001). Three-year survival (CPB 69 +/- 13%, OPCAB: 82 +/- 12%, p = 0.47) and reintervention rates (CPB: 3 [21%], OPCAB: 3 [17%], p = 0.33) were similar between the groups. CONCLUSIONS: RCLT is an effective and safe approach for circumflex artery revascularization with excellent short- and mid-term results using either technique. The OPCAB technique is associated with reduced blood product utilization and shorter ICU and hospital length of stay and, therefore, is more cost-effective.     

Off-pump coronary artery bypass surgery for critical left main stem disease: safety, efficacy and outcome.

OBJECTIVES: To determine whether patients with critical left main stem (LMS) coronary artery disease can undergo off-pump coronary artery bypass (OPCAB) surgery safely and successfully. METHODS: From May 1996 to March 2000 data for patients with critical (> or =50%) LMS stenosis who underwent conventional coronary artery bypass surgery with cardiopulmonary bypass (CCAB) or without (OPCAB) were collected prospectively using the Patient Analysis & Tracking System. A reusable pressure stabilizer, intra-coronary shunts and a single posterior pericardial stitch exposure technique were used in all OPCAB cases. Non-randomized, retrospective data analysis included demographic and preoperative risk factors, operative details, clinical outcome and early follow-up. RESULTS: During the study period 387 patients with LMS stenosis underwent surgery (OPCAB n=75, CCAB n=312). Groups were similar in terms of preoperative and intraoperative variables although CCAB patients received significantly more grafts per patient (3.1+/-0.73 vs. 2.6+/-0.76, P< or =0.001). Mortality was similar in both groups (OPCAB 1.3% vs. CCAB 2.6%). OPCAB patients when compared to CCAB patients had a lower requirement for postoperative inotropes (12.0% vs. 38.1%, P=0.0001), temporary postoperative pacing (2.7% vs. 10.1%, P=0.02), and blood product transfusion (6.7% vs. 31.4%, P<0.0001), a lower incidence of postoperative chest infection (0% vs. 6.7%, P=0.02) and a slightly reduced postoperative length of stay (7.9+/-5.46 vs. 8.3+/-5.11 days, P=0.01). At 24 months follow-up, CCAB and OPCAB actuarial survival was 94.1+/-1.7% and 97.7+/-2.3%, respectively. CONCLUSIONS: OPCAB surgery is safe and effective in patients with critical LMS disease.