In-hospital outcomes of off-pump versus on-pump coronary artery bypass procedures: a multicenter experience.

BACKGROUND: Concern about the possible adverse effects of the cardiopulmonary bypass (CPB) pump and advances in retractors and operative techniques to access all coronary segments have resulted in increased interest in off-pump coronary artery bypass (OPCAB) procedures. Four of the Northern New England Cardiovascular Disease Study Group centers initiated OPCAB programs in 1998. We compared the preoperative risk profiles and in-hospital outcomes of patients done off-pump with those done by conventional coronary artery bypass (CCAB) with CPB. METHODS: Between 1998 and 2000, 1,741 OPCAB and 6,126 CCAB procedures were performed at these four medical centers. Minimally invasive direct coronary artery bypass grafting procedures were excluded. Data were available for patient and disease risk factors, extent of coronary disease and adverse in-hospital outcomes. RESULTS: The OPCAB and CCAB groups were somewhat different in their preoperative patient and disease characteristics. The OPCAB patients were more likely to be female and to have peripheral vascular disease. The CCAB patients were more likely to have an ejection fraction less than 0.40 and be urgent or emergent at operation. However, overall predicted risk of in-hospital mortality, based on preoperative factors, was similar in the OPCAB and CCAB groups; the mean predicted risk was 2.6% (p = 0.567). Crude rates of mortality (2.54% OPCAB versus 2.57%, CCAB), intraoperative or postoperative stroke (1.33% versus 1.82%), mediastinitis (1.10% versus 1.37%), and return to the operating room for bleeding (3.46% versus 2.93%) did not differ significantly. The OPCAB patients did have a statistically significant reduction in the need for intraoperative or postoperative intraaortic balloon pump support (2.31% versus 3.41%; p = 0.023) and in the incidence of postoperative atrial fibrillation (21.21% versus 26.31%; p < 0.001). Adjustment for preoperative risk factors and extent of coronary disease did not substantially change the crude results. Median postoperative length of stay was significantly shorter (5 days versus 6 days, p < 0.001) for OPCAB patients than for CCAB patients. CONCLUSIONS: This multicenter study showed that patients having OPCAB are not exposed to a greater risk of short-term adverse outcomes. These data also provided evidence that patients having OPCAB have significantly lower need for intraoperative or postoperative intraaortic balloon pump, lower rates of postoperative atrial fibrillation, and a shorter length of stay.     

Early and medium-term results after on-pump and off-pump coronary artery surgery: a propensity score analysis

BACKGROUND: Comparative publications on beating-heart off-pump coronary artery bypass grafting (OPCAB) surgery versus conventional coronary artery bypass grafting (CCAB) surgery frequently do not offer conclusive information because of investigator bias. METHODS: Trying to eliminate this problem, a propensity score analysis of the data of all CCAB patients (n = 517) and OPCAB patients (n = 133) operated on by the same surgeons during the same time period (1998 to 2001) was applied. After matching patients with similar propensity score values, 97 CCAB patients and 72 OPCAB patients entered the final analysis. RESULTS: Early results were similar in both groups: the 30-day mortality reached 1.4% in the CCAB group and 2.8% in the OPCAB group; strokes did not happen. Perioperative myocardial infarctions occurred in 4.1% of the CCAB patients and 4.3% of the OPCAB patients. Drainage blood loss in the first 24 hours after surgery (830 +/- 687 mL, CCAB group; and 909 +/- 678 mL, OPCAB group) was similar (p = 0.06) in both groups. Medium term results (freedom from percutaneous transluminal coronary angioplasty or reoperation, freedom from myocardial infarction, freedom from stroke, and the quality of life) also were not significantly different between the off-pump and on-pump groups after a mean follow-up of 27 +/- 11 months. CONCLUSIONS: Our results suggest that elective-surgery patients with coronary artery disease can be operated on either on-pump or off-pump with the same early and late mortality and morbidity.     

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.     

Myocardial revascularization in patients with low ejection fraction < or =35%: effect of pump technique on early morbidity and mortality

BACKGROUND AND AIM: Left ventricular dysfunction is an important predictor of in-hospital mortality. Surgical risk among these patients remains high. The present study is conducted to evaluate the difference in early morbidity and mortality among patients with compromised left ventricular function (LVF) after myocardial revascularization using either off-pump or on-pump coronary artery bypass graft. METHODS: Between April 2000 and April 2004, 150 patients with ejection fraction (EF) < or =35% underwent isolated coronary artery bypass grafting. Eighty-four patients underwent conventional bypass (mean EF 30.1%+/- 4.2) and 66 patients had off-pump coronary artery bypass (mean EF 27.5%+/- 5.5). Different variables (preoperative, intraoperative, and postoperative) were evaluated and compared. Determination of operation risk was done using EuroSCORE. Patients who underwent OPCAB were more risky due to a high percentage of associated comorbidities, mean EuroSCORE was 12.96 +/- 13.21 in comparison to 8.47 +/- 10.22 in CCAB. RESULTS: The mean operative mortality was 8.7%. Patients who underwent OPCAB had a lower operative mortality than CCAB (6.1% vs. 10.7%) inspite of a higher preoperative predicted risk score. Completeness of revascularization was higher among the CCAB group (85.7% vs. 69.7%; p = 0.01). Subsequently, the mean number of grafts was significantly higher among this group (3.4+/-0.7 vs. 2.0 +/-0.9; p < 0.001). On the other hand, morbidity was significantly higher in CCAB (35.7% vs. 19.7%; p = 0.03). However, the incidence of both myocardial infarction and atrial fibrillation was more among OPCAB. CONCLUSIONS: Patients with left ventricular dysfunction are high-risk group. These patients can benefit from myocardial revascularization using either off-pump or conventional CABG, but both are associated with a higher mortality and morbidity than those with normal ventricle. The use of off-pump CABG resulted in better clinical outcome and mortality, but less number of grafts performed than those with conventional CABG especially in patients with lowest EF.     

Safety and efficacy of off-pump coronary artery bypass grafting

BACKGROUND: We evaluated the application of the off-pump coronary artery bypass (OPCAB) procedure relative to safety and efficiency as measured by operative mortality postoperative complications and longitudinal outcome. METHODS: Three hundred and fifty OPCAB patients were compared to 3,171 on-pump or conventional coronary artery bypass (CCAB) patients between January 1, 1997 and December 31, 1998. The groups were divided into three preoperative predicted risk categories: low-risk (0 to 2.59%), medium-risk (2.6 to 9.9%), and high-risk (> or =10%). Society of Thoracic Surgeons National Cardiac Surgery Database definitions and predicted risk group models were utilized to compare all preoperative, intraoperative, and postoperative variables using univariate analysis. RESULTS: Overall comparison of the immediate outcome of CCAB and OPCAB shows little statistical significance in the variables analyzed. The operative mortality was 3.4% in both groups. When the immediate outcome was compared between groups (CCAB vs OPCAB), as well as individual risk groups (low, medium, and high), similar patterns of operative variables and postoperative complications were observed. The operative mortality in the low-risk group was 1.1% for CCAB and 1.4% for OPCAB; 7% for CCAB and 6% for OPCAB in the medium-risk group; and in the high-risk group 28.5% for CCAB compared to 7.7% for OPCAB group (p = 0.008). Short-term follow-up shows a trend of increased recurring angina and reinterventional procedures in the OPCAB patients. CONCLUSIONS: Safety for OPCAB is assessed through retrospective data review. Longitudinal follow-up for survival, reintervention, and quality of postoperative document efficacy and patency rates, compared to on-pump procedures, is mandatory. This study documented the immediate safety of the OPCAB procedure. Preliminary findings at 1-year follow-up is an important finding in this study, but it is not conclusive at this time. Long-term longitudinal follow-up is required to assess the future effectiveness of OPCAB.     

High thoracic epidural anesthesia for coronary artery bypass grafting using two different surgical approaches in conscious patients

Recent developments in coronary artery bypass graft surgery (CABG) without cardiopulmonary bypass made the sole use of high thoracic epidural anesthesia (TEA) in conscious patients feasible. Previously, TEA has been reported only for single-vessel CABG via lateral thoracotomy. We investigated the feasibility and complications of sole TEA in 20 patients undergoing beating-heart arterial revascularization via partial lower sternotomy for single-vessel disease (minimally invasive direct coronary artery bypass grafting [MIDCAB] technique; n = 10) or complete median sternotomy for multivessel disease (off-pump coronary artery bypass grafting [OPCAB] technique; n = 10). An epidural catheter was inserted at the T1-2 or T2-3 interspace. An epidural infusion of ropivacaine 0.5% and sufentanil 1.66 micro g/mL was started to establish anesthetic levels at C5-6 for OPCAB and at T1-2 for MIDCAB. Nine OPCAB and eight MIDCAB procedures were completed while patients were awake and spontaneously breathing during the entire procedure. Because of surgical pneumothorax (OPCAB), insufficient anesthesia, or phrenic nerve palsy (both MIDCAB), three patients required intraoperative conversion to general anesthesia. The heart rate decreased significantly (P < 0.05) by 10%-15% in both groups during the procedure. Compared with baseline (B), mean arterial blood pressure (mm Hg) was decreased significantly only during coronary anastomosis (CA) (B(OPCAB), 95 +/- 11; CA(OPCAB), 68 +/- 9; B(MIDCAB), 86 +/- 10; CA(MIDCAB), 73 +/- 10; P not significant between groups). PaCO(2) increased from 42 +/- 2 mm Hg to 46 +/- 7 mm Hg (P < 0.05) throughout the perioperative course during OPCAB, whereas it remained almost unaltered during MIDCAB procedures. All patients rated TEA as "good" or "excellent." In conclusion, we demonstrated that the sole use of TEA for MIDCAB and OPCAB procedures was feasible and provided a high degree of patient satisfaction in our small and highly selected cohorts. IMPLICATIONS. The sole use of high thoracic epidural anesthesia was studied in 20 patients who underwent beating-heart coronary artery bypass grafting using either median or partial lower sternotomy while awake.     

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.     

Surgical revascularization in patients with poor left ventricular function: on- or off-pump?

BACKGROUND: Patients with left ventricular dysfunction and low ejection fraction (EF) are at high-risk of complication and mortality after coronary artery bypass grafting (CABG). The potential success of off-pump CABG in this high-risk population has yet to be determined. The purpose of this study is to compare the outcome of off-pump coronary artery bypass (OPCAB) and conventional coronary artery bypass (CCAB) in patients with poor left ventricular function, all from a single institution. METHODS: Data on patient demographics, preoperative risk factors, operative and postoperative outcomes were collected retrospectively on all patients having undergone isolated CABG between January 1, 1998, and October 31, 2001. RESULTS: A total of 77 patients (31 OPCAB/46 CCAB) were identified as having an ejection fraction (EF) of < or = 0.35. Of these, 52 had EF < or = 0.30 (21 OPCAB/31 CCAB) and 31 patients had EF < or = 0.25 (10 OPCAB/21 CCAB). Operative mortality was 3.2% after the OPCAB procedure versus 10.9% for the CCAB (p = 0.39). Use of intraaortic balloon pump (6.5%) was rarely required. The OPCAB procedure resulted in significantly less requirement for blood transfusions (p < 0.05), fewer distal anastomoses per patient (p < 0.01), and a higher incidence of atrial fibrillation (p < 0.05) compared with CCAB. CONCLUSIONS: Patients with poor left ventricular function may undergo surgical revascularization using off-pump technique with relatively good results and low mortality levels. The lower number of grafts performed on the off-pump procedure did not seem to affect clinical outcomes.     

Risk of retinal microembolism after off-pump and on-pump coronary artery bypass surgery

AIM: In order to investigate the neuroprotective efficacy of off-pump coronary artery bypass surgery (OPCAB) over conventional on-pump coronary artery bypass surgery (CCAB), we have performed a prospective randomized study evaluating retinal circulation changes after OPCAB and CCAB. METHODS: Twenty patients were randomized to OPCAB or CCAB. Retinal fluorescein angiography and 60 degrees black-and-white as well as color fundus photographs of both eyes of each patient were taken 1 to 24 h before and 5 to 6 days after the operation. RESULTS: Patients undergoing OPCAB had more severely stenosed carotid arteries (P=0.075), higher incidence of slightly diseased ascending aorta (P=0.087) and higher Northern New England Cardiovascular Study Group stroke risk score (P=0.075). Neither stroke nor transient ischemic attack occurred postoperatively in these patients. Inferotemporal retinal arterial embolization and microinfarction was detected in one patient after CCAB, but in none of the OPCAB group. CONCLUSION: The risk of retinal embolism can be minimized by the use of OPCAB and, most likely, by adequate epiaortic ultrasound scanning of the ascending aorta and avoiding clamping in case of severely diseased aorta.     

Is low ejection fraction safe for off-pump coronary bypass operation?

BACKGROUND: Does the manipulation of the heart during off-pump coronary artery bypass (OPCAB) procedure further compromise the hemodynamic stability of a patient with depressed left ventricular function compared with the conventional coronary artery bypass (CCAB) approach? Does this manipulation induce a more dramatic hypoperfused state that may contribute to an increase in the incidence of related complications or mortality? This retrospective review of data attempted to answer the above concern. METHODS: Between January 1, 1998, and June 30, 1999, 177 patients with ejection fractions of 30% or less underwent full sternotomy coronary artery bypass grafting at our institution. Of these patients, 45 underwent OPCAB procedures and 132 patients underwent CCAB. Pre-, intra-, and postoperative variables as identified by The Society of Thoracic Surgeons National Cardiac Surgery Database were compared using univariate and logistical regression analysis. RESULTS: Despite recognized hemodynamic derangement during cardiac displacement, these groups of OPCAB patients appeared to tolerate the procedure well. Univariate analysis of cardiac enzyme leak and blood loss was statistically significant in the OPCAB patients. Utilizing regression analysis, cardiopulmonary bypass was the only predictor for all postoperative complications. CONCLUSIONS: Multivessel coronary artery bypass utilizing the OPCAB approach in patients with depressed left ventricular function of equal to or less than 30% is appropriate and applicable. Analysis of CCAB and OPCAB variables was nonsignificant except for operative and postoperative blood loss and peak cardiac enzyme leak. Attention to intraoperative detail and hemodynamic management could be credited for the success with OPCAB.     

Early results of off-pump coronary artery bypass

Objective: The purpose of this study is to compare the operative results of off-pump coronary artery bypass (OPCAB) and on-pump (conventional) coronary artery bypass (CCAB), to clarify qualitative problems and whether OPCAB is less invasive or not. Methods: OPCAB was consecutively performed in 63 patients and CCAB in 63 patients between July 1998 and December 2003. Results: The mean number of bypass grafts was 2.43 ±0.82 in the OPCAB group and 2.70±0.71 in the CCAB group (p=0.096). In-hospital mortality was 0% in the OPCAB group and 3.2% in the CCAB group. The incidence of perioperative myocardial infarction was 0% in the OPCAB group and 3.2% in the CCAB group. The incidence of postoperative major complications was significantly lower in the OPCAB group than in the CCAB group (OPCAB group=4 complications, CCAB group=13 complications). Cerebrovascular accidents occurred in 1.6% of patients in both groups. The incidence of sternal infection or mediastinitis was 0% in the OPCAB group and 3.2% in the CCAB group. The early patency rate of graft was 94.0% in the OPCAB group and 92.8% in the CCAB group, and was not significantly different (p=0.822). Conclusion: Operative mortality and major complications after surgery in OPCAB were lower than that in CCAB. The early patency rate in OPCAB was as good as that in CCAB. It is considered that OPCAB is less invasive and the quality of bypass in OPCAB is as good as that in CCAB.     

Is routine application of off-pump coronary artery bypass grafting warranted?

The limitation and indication of off-pump coronary artery bypass grafting (OPCAB) remain controversial. Since May 1999, we have applied OPCAB for all isolated coronary bypass cases routinely. Intraoperative conversion to CCAB occurred in 8 patients (10.8%). The main reasons for conversion were intramyocardial coronary arteries and arythmia-induced hemodynamic instability in the acute phase of myocardial infarction. We evaluated the results of OPCAB as compared to conventional coronary artery bypass (CCAB) as a historical control. The operative mortality was 1.6% in both groups. Postoperative complications including renal failure and requirements of circulatory support were significantly less in OPCAB. Postoperative max CPK-MB value, the amount of postoperative bleeding and the requirement of transfusion were also significantly less in OPCAB. Only neurological complication in OPCAB was temporary delirium in a high-aged patient, whereas three patients developed neurological complications including permanent stroke in CCAB. Right heart bypass was effectively utilized to maintain hemodynamics and expose the posterior vessels in patients with severely dilated and poorly functioning left ventricle (EF: 24-31%) and a patient with multiple severe stenosis in cerebral arteries. Coronary angiogram performed after the operation demonstrated 94% of graft patency. These results warrant the further application of OPCAB for multivessel surgical revascularization.     

Off-pump surgery decreases postoperative complications and resource utilization in the elderly.

BACKGROUND: Bypass surgery in the elderly (age >70 years) has increased mortality and morbidity, which may be a consequence of cardiopulmonary bypass. We compare the outcomes of a cohort of elderly off-pump coronary artery bypass (OPCAB) patients with elderly conventional coronary artery bypass grafting (CABG) patients. METHODS: Chart and provincial cardiac care registry data were reviewed for 30 consecutive elderly OPCAB patients (age 74.7 +/- 4.2 years) and 60 consecutive CABG patients (age 74.9 +/- 4.1 years, p = 0.82) with similar risk factor profiles: Parsonnet score 17.2 +/- 8.1 (OPCAB) versus 15.6 +/- 6.5 (CABG), p = 0.31; and Ontario provincial acuity index 4.5 +/- 1.9 (OPCAB) versus 4.3 +/- 2.0 (CABG), p = 0.65. RESULTS: Mean hospital stay was 6.3 +/- 1.8 days for OPCAB patients and 7.7 +/- 3.9 days for CABG patients (p < 0.05). Average intensive care unit stay was 24.0 +/- 10.9 h for OPCAB patients versus 36.6 +/- 33.5 h for CABG patients (p < 0.05). Atrial fibrillation occurred in 10.0% of OPCAB patients and 28.3% of CABG patients (p < 0.05). Low output syndrome was observed in 10% of OPCAB patients and 31.7% of CABG patients (p < 0.05). Cost was reduced by $1,082 (Canadian) per patient in the OPCAB group. Postoperative OPCAB graft analysis showed 100% patency. CONCLUSIONS: OPCAB is safe in the geriatric population and significantly reduces postoperative morbidity and cost.     

Off-pump coronary artery bypass grafting in patients with significant left ventricular dysfunction

Objective  Off-pump coronary artery bypass grafting (OPCAB) is known to preserve left ventricular function better than conventional coronary artery bypass grafting (CCAB). This study was carried out to investigate the safety, feasibility and efficacy of off-pump coronary artery bypass grafting in patients with significant left ventricular dysfunction. Methods  Three hundred and eighty eight consecutive patients with preoperative left ventricular ejection fraction ≤ 39% who underwent CABG between January 2001 through October 2007 were included in this retrospective study. Two hundred and eleven patients were operated by off-pump technique (group 1) and 178 patients were operated by on-pump technique (CCAB) (group 2). The postoperative outcomes were analyzed. Of these, 204 (52.57%) patients were diabetics, 355 (91.49%) patients had documented prior myocardial infarction, 316 (81.44%) patients were in canadian cardiovascular society(CCS) class III and 47 (12.11%) patients were in CCS class IV. Results  There was no significant difference in the number of grafts per patient between the two groups [group 1 3.02 ± 0.76 vs group 2 3.18 ± 0.72 (P=0.07) and the index of completeness of revascularization was comparable [1.08 ± 0.08) (OPCAB) vs 1.04 ± 0.06 (CCAB) (p=0.52)] The left internal thoracic artery was anastomosed to left anterior descending artery in 98% of patients. Operative mortality was 2.8% (6 deaths) following OPCAB and 3.93% (7 deaths) following CCAB (p=0746). Postoperative usage of IABP support was higher in CCAB group (12 patients vs 4 patients: P<0.03) and usage of moderate or higher doses of inotropic support was also higher in the conventional group (p<0.0006). More worsening of preexisting renal insufficiency was observed in CCAB group (p=0.01) and no significant difference in the incidence of atrial fibrillation was observed between the groups. Conclusions  Off-pump coronary artery bypass grafting is feasible and safe in patients with depressed left ventricular function and the postoperative morbidity was less in OPCAB group compared to on-pump group.     

Rationale of off-pump coronary artery bypass grafting for left main trunk disease

Objective: Off-pump coronary artery bypass grafting (OPCAB) remains controversial in patients with left main trunk (LMT) disease because of a concern about the ability to tolerate hemodynamic instability. This study examined the safety of OPCAB for LMT disease compared with conventional coronary artery bypass grafting (CABG). Methods: Between April 1997 and December 2002, 257 consecutive patients with LMT stenosis who underwent CABG were enrolled. There were 98 patients who received CABG with the aid of cardiopulmonary bypass (CCAB group), and 159 patients who received OPCAB (OPCAB group). Results: There was no patient who converted to on-pump intraoperatively due to hemodynamic instability. Both intraoperative blood loss and blood transfusion incidence were lower in the OPCAB group. Postoperative course was similar, however, pulmonary complications were less observed postoperatively in the OPCAB group. No hypoperfusion syndrome was seen postoperatively in both groups. The average number of anastomosis was 3.2±1.1 in the CCAB group and 3.2±1.0 in the OPCAB group (p=0.645). Total arterial OPCAB with an aorta no-touch technique was achieved in 142 patients (89.3%) in OPCAB group. Postoperative angiography was performed in 95 patients in CCAB (96.9%), and in 141 patients in OPCAB (89.8%). Although graft patency of arterial grafts was good in both groups (100% in CCAB and 98.3% in OPCAB), saphenous vein graft patency was slightly lower in both groups (93.4% in CCAB and 76.5% in OPCAB) compared with arterial grafts. Conclusion: OPCAB allows a safe and effective treatment of LMT disease.     

Single vessel revascularization with beating heart techniques -- minithoracotomy or sternotomy?

OBJECTIVE: The purpose of the study was to evaluate the best surgical approach in off-pump single vessel revascularization of the left anterior descending coronary artery (LAD). METHODS: In 256 patients a single left internal mammary artery (LIMA) to LAD bypass was performed with beating heart techniques through a left anterior minithoracotomy (minimally invasive direct coronary artery bypass (MIDCAB), n=129) or a full sternotomy (off-pump coronary artery bypass (OPCAB), n=127). RESULTS: In the OPCAB group, significantly more severe comorbidities (P=0.001) and redo-operations were noted (P<0.001). Conversion to sternotomy or CPB was necessary in five MIDCAB patients and one OPCAB patient. No cerebrovascular accident was seen in both groups. There was no hospital death in MIDCAB- and two deaths in OPCAB procedures (P=ns). There was a significant reduction in time of surgery (P=0.028) and coronary occlusion (P=0.009) in the OPCAB group. No differences in postoperative ventilation time, ICU stay and length of hospital stay were recorded between groups. Wound infections occurred in six MIDCAB patients (4.7%) and one OPCAB patient (0.8%). Early postoperative reoperation due to graft failure was necessary in three patients after MIDCAB and two patients after OPCAB (P=ns). Confirmed by angiography, the early graft patency rate was 96 and 98%, respectively (P=ns). CONCLUSIONS: Both beating heart techniques showed good results with low hospital mortality, low early complications and comparable angiographic results. Nevertheless, MIDCAB is a challenging technique as demonstrated by the longer times of surgery and coronary occlusion with a tendency towards a higher risk of conversion and wound infection. Thus, this technique should only be performed in selected patients with favourable coronary anatomy. Through a sternotomy approach, single vessel revascularization can be performed safely off-pump even in high-risk patients.     

Coronary revascularization of the circumflex system: different approaches and long-term outcome

BACKGROUND: Minimally invasive direct coronary artery bypass, without cardiopulmonary bypass, through a left lateral thoracotomy approach (lateral MIDCAB), is a safe alternative to coronary artery bypass surgery using cardiopulmonary bypass (on-pump CABG) of the circumflex system via median sternotomy. However, it is unknown whether lateral MIDCAB may yield an improved long-term outcome over the conventional on-pump median sternotomy approach. METHODS: We compared the perioperative outcomes of patients undergoing lateral MIDCAB (n = 34) versus conventional on-pump CABG of the circumflex system (n = 16) from June 1996 to July 1999. The two groups were similar with respect to baseline characteristics and risk stratification. Patients who required only one or two grafts for complete revascularization were included. RESULTS: Lateral MIDCAB patients had a lower need than on-pump CABG patients for intraoperative (12% MIDCAB vs 43% on-pump CABG, p = 0.03) and postoperative transfusions (29% vs 69%, p = 0.01), had fewer neuropsychologic changes (0% vs 19%, p = 0.03), and had a lower rate of postoperative atrial fibrillation (12% vs 44%, p = 0.02). Lateral MIDCAB was also associated with a significantly lower postoperative length of stay (5 +/- 2 vs 7 +/- 3 days, p = 0.02). Actuarial survival at a mean period of follow-up of 19 +/- 11 months was 97% for the lateral MIDCAB versus 88% for the on-pump CABG group (p = 0.6). Event-free survival was 88% for lateral MIDCAB versus 81% for on-pump CABG (p = 0.1). CONCLUSIONS: Lateral MIDCAB may safely be performed in patients with isolated coronary artery disease of the circumflex system with improved early morbidity and an abbreviated hospital stay compared with conventional median sternotomy on-pump CABG.     

Coronary artery bypass in patients 80 years and over: is off-pump the operation of choice?

BACKGROUND: Octogenarians are at increased risk for perioperative morbidity and mortality after coronary artery bypass. In this study we compared our experience with patients undergoing on-pump coronary artery bypass (CAB) and those undergoing off-pump coronary artery bypass (OPCAB) to assess outcomes. METHODS: We used hospital database analysis in patients 80 years and older who underwent nonemergent coronary artery bypass with (N = 169) and without (N = 60) cardiopulmonary bypass from January 1999 through June 2001. RESULTS: Both groups were at increased perioperative risk based on the Society of Thoracic Surgeons risk model (7.7% OPCAB vs 5.8% CAB, p = 0.03). There were no operative deaths in the OPCAB group but there were eight (4.7%) in the CAB group (p = NS). Perioperative stroke (0% OPCAB vs 7.1% CAB, p = 0.04), prolonged ventilation (1.7% OPCAB vs 11.8% CAB, p = 0.02), and transfusion rate (33% OPCAB vs 70.4% CAB, p < 0.001) were all lower in the OPCAB group. A shorter hospital stay (6.3 days OPCAB vs 11.5 days CAB, p < 0.001) resulted in lower hospital cost in the OPCAB group ($9,363 OPCAB vs $12,312 CAB, p < 0.001). CONCLUSIONS: In this study, off-pump coronary artery bypass grafting in elderly patients was associated with fewer complications, a shorter hospital stay, and lower hospital cost. Off-pump coronary artery bypass grafting may be the operation of choice for octogenarians requiring surgical myocardial revascularization.     

Coronary artery bypass grafting without cardiopulmonary bypass: MIDCAB and OPCAB

Minimally invasive direct coronary artery bypass grafting via left anterior small thoracotomy (MIDCAB) and coronary artery bypass grafting without cardiopulmonary bypass (OPCAGB) are accepted technique as less invasive than conventional coronary artery bypass grafting (CABG). We reported our experience with these procedures. From 1996 to December 1999, 176 patients underwent MIDCAB or OPCAB with the internal thoracic artery. The left internal thoracic arteries were used for grafting of the left anterior descending artery (LAD) in 131 patients, LAD and diagonal branches sequentially in 8 patients, using free radial artery conduits for grafting of the right coronary artery (RAC) or left circumflex (LCx) in 7 patients, using radial artery conduits as Y-graft from LAD for grafting of the RAC or LCx in 24 patients, and bilateral internal thoracic artery grafting was performed in 4 patients. One patient (0.6%) died in the hospital. One patient (0.6%) had perioperative myocardial infarction. No patient had cerebrovascular accident and sever wood infection. One-hundred-seventy-four patients (98.8%) had resolution of their angina symptom.     

Usefulness of OPCAB from the viewpoint of fluctuations in the level of blood natriuretic peptides

Fluctuations in the level of blood natriuretic peptides (ANP and BNP) were compared between 41 patients who underwent conventional coronary artery bypass (CCAB) and 19 patients who underwent off-pump coronary artery bypass (OPCAB). A blood sample was collected before surgery, and 6, 12 and 24 hours; 2, 3, 5 and 7 days; and 1 month after the end of extracorporeal circulation. There were no significant differences in left ventricular ejection fraction (LVEF) before and after surgery in either group or between the two groups. On average, 3.3 +/- 1.0 bypass grafts were used for the CCAB group, and 2.2 +/- 0.8 grafts for the OPCAB group. Furthermore, the maximum postoperative creatine phosphokinase-MB (CK-MB) level for the CCAB group was 49.1 +/- 17.5 IU/l, whereas that for the OPCAB group was significantly lower at 23.2 +/- 24.8 IU/l. The preoperative level of blood ANP for the CCAB group was 24.6 +/- 19.9 pg/ml while that for the OPCAB group was 39.3 +/- 29.5 pg/ml, but there was no significant difference between the two groups. In both groups, the level of blood ANP reached a peak three days after the end of extracorporeal circulation and then decreased after that point. Although the level of blood ANP for the OPCAB group decreased to 51.4 +/- 26.4 pg/ml one month after the end of extracorporeal circulation, that for the CCAB group one month after the end of extracorporeal circulation remained significantly high at 61.3 +/- 30.6 pg/ml, when compared to that before surgery. Furthermore, the preoperative level of blood BNP for the CCAB group was 40.0 +/- 35.2 pg/ml and that for the OPCAB group was 75.5 +/- 59.7 pg/ml, but there was no significant difference between the two groups. Then, in both groups, the level of blood BNP reached a peak 2-5 days after the end of extracorporeal circulation and then decreased after that. Whereas the level of blood BNP for the OPCAB group decreased to 96.4 +/- 56.0 pg/ml one month after the end of extracorporeal circulation, that for the CCAB group one month after the end of extracorporeal circulation remained significantly high at 160.3 +/- 106.2 pg/ml when compared to that before surgery. The levels of ANP and BNP increased postoperatively for both OPCAB and CCAB groups since the following events caused a great degree of stress on the heart: general anesthesia, cardiac herniation, stabilizer compression, regional blood flow blockage and reperfusion injury. Although the level of natriuretic peptides for the CCAB group remained high one month after the end of surgical stress, that for the OPCAB group returned to near the preoperative level one month later, thus supporting the notion that OPCAB is less invasive.