Original Article

Does Coronary Artery Bypass Grafting Without Cardiopulmonary Bypass Reduce Costs in Cardiac Surgery?

E Hijazi

Citation

E Hijazi. Does Coronary Artery Bypass Grafting Without Cardiopulmonary Bypass Reduce Costs in Cardiac Surgery?. The Internet Journal of Thoracic and Cardiovascular Surgery. 2009 Volume 14 Number 2.

Abstract

Technical improvements in coronary revascularization over the past decade have led to a revival of interest in off-pump coronary artery bypass surgery. Cost containment in coronary artery bypass surgery is becoming increasingly important in modern hospital management. Therefore, further savings could be obtained by using a surgical technique able to decrease the fixed direct cost while maintaining clinical quality of care. Economic considerations are an extremely important issue in evaluating the role of off-pump coronary artery bypass grafting in the future of cardiac surgery, as off-pump coronary artery bypass grafting is expected to lower costs by reducing perioperative morbidity and recovery time. However, the acceptance of this procedure as a routine alternative for the treatment of coronary artery disease will depend on both long-term graft patency rates as well as a competitive market cost. This review examines these effects.

 

Introduction

Kolessov (1) reported the first experience with coronary artery surgery on the beating heart in 1967, but the technique was soon abandoned with the advent of cardiopulmonary bypass (CPB). However, off-pump coronary artery bypass grafting (OPCAB) has experienced a revival, beginning in the early 1990s with the work of Benetti et al (2) and Buffolo et al. (3). Their work in South America was motivated by economic considerations but demonstrated that unexpected benefits were associated with the avoidance of CPB and these includes much lower morbidity in high risk patients, aged 70 or older, the ischemia produced during this procedure is well tolerated independently from the coronary anatomy and the patient’s clinical picture. They have had maintenance of a normal septal function probably due to secondary preservation of physiologic homeostasis. The other unexpected benefits were low use of blood products with decreased the chance of blood-transmitted disease and the cost of this procedure vs angioplasty is less. Also, concluded that the cost of this surgery vs surgery of coronary artery bypass grafting with cardiopulmonary bypass (CABG) has been less than 30 percent in their series of patients (2). Coronary artery bypass surgery (CABG) using cardiopulmonary bypass (CPB) relieves angina, while maintain the body circulation. Cardiac arrest using CPB provides a bloodless field and a perfectly still heart to perform a microvascular conduit to coronary anastomosis. Fifty years ago, a young surgeon, supported by a multidisciplinary team of physicians and technicians at the Mayo Clinic in Rochester, Minn, embarked on a planned series of clinical cases using a heart-lung machine to allow direct visualization of the inside of the opened human heart to repair otherwise fatal intracardiac defects (4). Of the initial 8 patients, 4 survived (5). This achievement was a breakthrough and showed the clinical feasibility of using a mechanical pump-oxygenator to support the circulation while working inside the heart. John W. Kirklin and his team had effectively made open heart surgery a therapy that could become widely available (4). Cardiopulmonary bypass was found to be an independent predictor of increased hospital costs and increased postoperative length of stay. The use of cardiopulmonary bypass during coronary artery bypass surgery has been associated with well known unwanted complications. CPB is known to induce inflammatory response that has been documented on the lungs, heart, central nervous system, kidneys, and gastrointestinal tract. Virtually all detrimental effects of this diffuse inflammatory response increase with longer durations of CPB (6). Stroke after conventional CABG is a devastating complication related to CPB, cannulation, or surgical manipulation, and cross-clamping of the ascending aorta. Also associated with increased CPB time are increased lengths of stay and hospital costs (7). Excessive bleeding is an important cause of morbidity and mortality after CPB (8). Transfusion of allogeneic blood products exposes the patient to additional risks (transfusion reactions, viral transmission, immunosuppression, and increased mortality rates) and increases the cost of the procedure (9). Consequently, if CPB can be avoided, a reduction in perioperative morbidity and mortality is anticipated, with faster recovery, shorter hospitalization, and less need of medical facilities and materials (10, 11). Using OPCAB further technical challenges presented with lateral and posterior coronary vessels exposure, because hemodynamic tolerance to the cardiac displacement was poor. However, with the advent of newer stabilizers and low-profile apical suction devices, this problem has been all but solved (12).

Methods

We used MEDLINE, EMBASE, Cochrane Controlled Trials Register (CCTR), Cochrane Database of Systematic Reviews (CDSR), Database of Abstracts of Reviews of Effects (DARE), Science Citation Index (SCI), Current Contents, NHS Economic Evaluation Database (NEED), and International Network of Agencies for Health Technology Assessment (INAHTA) databases were searched from the date of their inception to the end of December 2007, using the search terms off-pump bypass surgery, beating heart, coronary artery bypass, cost-effectiveness, economic analysis, and related keywords to search MEDLINE, In this search I retrieved 116 titles. Of these 35 titles were excluded, as the treatments in these studies were not randomly allocated; 8 titles concerning randomised trials on OPCAB with another comparison than CABG; 7 titles for which only an abstract and I could not found any reports. I selected 66 articles with full publications, 17 provide insufficient data to allow statistical pooling for the combined endpoint, leaving 49 titles. The selected 66 articles are the base line articles in the literatures that are relatively used as references in all recent studies comparing the off-pump coronary artery bypass surgery with conventional coronary artery bypass grafting. The study has been approved through The Jordanian University of Science and Technology Institutional Ethics Committee- Jordan/ Irbid.

Figure 1
Table 1 Depending on Grading of Recommendations and Levels of Evidence - Length of hospital stay, Mortality and Economics in OPCAB

Figure 2
Table 2 Average Resorce Use and Direct Medical Costs per Patient From:Reference number (50) - Nathoe HM, van Dijk D, Jansen EW, et al. A comparison of on-pump and off-pump coronary bypass surgery in low-risk patients. N Engl J Med 2003;348:394–

Figure 3
Table 3—Clinical Outcomes Following On –Pump vs Off- Pump From:Reference number (58) Keenan TD, Abu-Omar Y, Taggart DP. Bypassing the Pump Changing Practices in Coronary Artery Surgery. Chest. 2005 Jul;128(1):363-9. Van Dijk et al (48); Angelini et al (32); Puskas et al (12); Nathoe et al (49); Khan et al (57);Legare et al (53)

Discussion

The length of hospital stay and the incidence of death after CABG is a function of multiple variables primarily related to a patient's premorbid condition and the morbidity associated with the procedure. By reducing the morbidity rates associated with the procedure and decreasing the incidence of complications, the use of OPCAB has decreased the length of hospital stay and cost savings (13) – Table 1. There are many complications related to CPB. Systemic Inflammatory Response (SIRS) is one of these complications. SIRS has been documented in the lungs, heart, central nervous system, kidneys, and gastrointestinal tract. SIRS results from a cascade of events generated by the contact of plasma proteases and blood cells with the gaseous interface and bioincompatible surfaces of the CPB machine. Activation of plasma proteases generates pro-inflammatory mediators that activate leukocytes, vascular endothelial cells, and platelets. The resulting platelet degranulation, neutrophil and monocyte activation result in a cytokine release syndrome and, in extreme cases, the generation of a systemic inflammatory response (14, 15). Excessive bleeding is an important cause of morbidity and mortality after CPB. Bleeding after cardiac surgery has several causes (16). The exposure of blood to synthetic, nonendothelial surfaces causes severe hemostatic defects that inhibit or alter many components of the thrombotic and fibrinolytic systems (9). Morbidity and mortality rates and hospital costs increase substantially when re-exploration for bleeding is necessary (17). Ascione, et al (11), in there study shows that transfusion requirements were higher in the on-pump group, and this reflected the significantly higher mean transfusion costs, re-entry for bleeding occurred infrequently in the OPCAB group. Puskas, et al (18), in a prospective randomized study he included 51 off-pump patients who were seen from November 1996 through December 1997 and underwent off-pump CABG by a single surgeon at Crawford Long Hospital, Emory University. The control group included 245 patients, for a total sample of 296 patients. More than half of the patients in the control group required transfusion of one blood product or more during hospitalization, whereas less than a quarter of the off-pump group received any blood products. Permanent neurologic dysfunction (stroke or coma) after conventional CABG is a devastating complication. Cerebral injury is considered to be the most significant and disabling complication of CABG. Stroke occurs in roughly 3% of patients after CABG, although up to two thirds of patients show a cognitive decline of variable duration (19). Although the pathogenesis of cerebral injury and cognitive dysfunction after cardiac surgery is multifactorial, there is increasing evidence that multiple microemboli arising from the ascending aorta, the heart chambers, or the bypass circuit are the primary pathophysiologic mechanisms producing diffuse ischemic cerebral injury (20). However, reducing cerebral microembolization by avoiding CPB has not resulted in a statistically significant reduction in the incidence of stroke and postoperative neurocognitive dysfunction (13). The comparable incidence of postoperative stroke after OPCAB may be attributable to aortic manipulation related to the use of a side-biting clamp that is applied during the construction of the proximal anastomoses (21). Gastrointestinal dysfunction following cardiac surgery is another CPB morbidity that might occur; it's about 2.5% of patients but with a disproportionate mortality (about 33%) (22). CPB is associated with significant physiologic alterations in mucosal perfusion, epithelial permeability, edema formation, and blood flow regulation. Inhibition of C5a limits neutrophil-mediated impairment of ileal microvascular regulation after bypass, but does not improve extravascular mesenteric dysfunction after CPB (23). A prospective, randomised study done by Raja, et al (24) was designed to define the role of cardiopulmonary bypass (CPB) and cardioplegic arrest in the pathogenesis of gastrointestinal complications following coronary artery surgery. This prospective, randomised study was designed to define the role of cardiopulmonary bypass (CPB) and cardioplegic arrest in the pathogenesis of gastrointestinal complications following coronary artery surgery. They concluded that cardiopulmonary bypass, inclusive of cardioplegic arrest, is the main independent predictor of post-operative gastrointestinal complications in patients undergoing coronary revascularisation. Renal dysfunction is another complication of CPB. The etiology of renal dysfunction after cardiac surgery is multi-factorial (25). However, renal hypoperfusion and inflammatory damage resulting from CPB are widely regarded as the most important causes of acute renal failure (26, 27). Beating Heart versus Cardioplegic Arrest Studies (BHACAS-1 study) (28), as well as a non-randomized prospective study (29), demonstrated a significant reduction in glomerular (cretonnes clearance) and tubular function (fractional excretion of sodium and free water clearance) in on- pump compared to off-pump surgery (29). During CPB, before and after cardioplegia or fibrillatory arrest, the heart, like all other organs and tissues, is subject to microemboli, protease and chemical cytotoxins, activated neutrophils and monocytes, and regional hypoperfusion (30). Both myocardial edema and distention of the flaccid cardioplegic heart during aortic cross-clamping reduce myocardial contractility (31). Furthermore, if myocardial contractility is weak, excessive preloading or high after loading during weaning from CPB increases ventricular end-diastolic volume, myocardial wall stress, and oxygen consumption (30). Off-pump theoretically should eliminate myocardial injury. In the randomized trial conducted by Angelini and colleagues (32) the frequency of myocardial infarction was reduced in the Off-pump group (2%), relative to the On-pump group (4%), at 2 years of follow-up. Atrial fibrillation (AF), the most common complication of CABG with CPB, occurs in 20% to 40% of patients (33). By avoiding the atrial myocyte alterations that result from aortic cross-clamping and avoiding the systemic inflammatory response to CPB, OPCAB should decrease the incidence of postoperative AF (13). There is a general consensus from randomized trials (12, 34, 35) and prospective non- randomized cohort studies (36, 37) that CABG performed using CPB and cardioplegic arrest is associated with a significantly greater degree of myocardial injury than OPCAB. Pulmonary functions deteriorate significantly for at least 3.5 months after cardiac surgery. Preoperative cardiac ischaemic and failure symptoms are inversely related to perioperative pulmonary function tests (PFTs) (38). Compared to CABG with CPB, OPCAB was associated with a greater reduction in postoperative respiratory compliance associated with increased fluid administration and rotation of the heart into the right chest to perform posterolateral grafts. OPCAB yielded better gas exchange and earlier extubation but no difference in chest radiographs, spirometry, or rates of death, pneumonia, pleural effusion, or pulmonary edema (39). Most randomized controlled trials (RCTs) that have recruited low-risk patients have shown that OPCAB definitely reduces the duration of ventilation and allows earlier extubation of OPCAB patients, yet its effects on respiratory mechanics, oxygenation, and effort of breathing are similar to those in patients undergoing CABG with CPB (13). Many authors have reported series of OPCAB operations (3, 40, 41). Although the mortality rates obtained have been excellent, concern has been raised about a decrement in graft patency rates (42). Lateral and posterior vessels presented technical challenges, because hemodynamic tolerance to the cardiac displacement necessary for exposure was poor. Recently, cardiac stabilization techniques were developed to facilitate bypass surgery on the beating heart. Other authors have described several devices of varying materials and functions, many of them barely reproducible, and for that very reason, they were not widely spread among the surgeons. However, mechanical stabilizers for off-pump coronary artery bypass graft surgery have changed this situation. A suction device, referred as to “Octopus”, which interposes the ventricular wall segment to be approached between two rows of suction cups stabilizing the segment and facilitating anastomosis performance (10,43). Stabilizers compressing the area to be stabilized were also developed and several commercial models manufactured. Oliveira, et al (44), in their experimental study about the hemodynamic disorders related to beating heart surgery using cardiac stabilizers. In swine they studied the hemodynamic changes secondary to the use of stabilizers for off-pump coronary artery bypass graft surgeries by means of both a suction device “Octopus” and a compression device (Speroni). Both stabilizers were studied placed on three vessels: anterior interventricular branch, posterior interventricular branch, and the left marginal artery of the circumflex branch. Each animal was randomly designed to application regarding the type of stabilizer and the target artery. The measurements were carried out 5 minutes before and after the stabilizer application. They concluded that both stabilizers have caused hemodynamic changes, but the compression device (Speroni) is more associated with changes than the suction device (Octopus). The Octopus (43) is one of the devices that can immobilize and present all sides of the beating heart. This allows OPCAB in patients with triple vessel disease (10). Excellent stabilization with good hemodynamic tolerance allowed surgeons to offer complete revascularization, and increasing proportions of their patients using Octopus OPCAB (45). With currently available instruments and improvements in surgical technique including the routine use of wide bilateral transverse diaphragmatic pericardiotomies, multiple deep pericardial traction sutures, and rotation of the heart into the right pleural space have recently allowed visualization of lateral and posterior coronary vessels in a high proportion of patients. This has led to a sharp increase in the number of grafts per patient in the OPCAB group (46). Hart, et al (45) in their study reviews the entire experience of the Medtronic Octopus System (Medtronic, Minneapolis, MN) for beating heart bypass from 7 surgeons. A total of 1,582 patients underwent attempted Octopus OPCAB. In-hospital or 30-day mortality was also low at 1.0% (range 0.0% to 3.7%). Postoperative length of stay averaged 5.8 days (range 4.9 to 7.6 days). The gratifyingly low rates of morbidity and mortality demonstrated in this large group of OPCAB patients compare favorably with the early outcomes described in recent reports of CPB-supported CABG by Sundt, et al (47), when they reviewed their early experience with total arterial revascularization using an internal thoracic artery (ITA) and radial artery T graft, between October 1, 1993, and September 1, 1998, involved 649 patients aged 30 to 85 years (mean, 60+/-10 years) had primary coronary artery bypass using an ITA and radial artery in a T-graft configuration. They did a total of 937 distal anastomoses were performed with the left ITA (1.4 per patient) and 1,452 with the radial artery (2.2 per patient). There was one perioperative death (0.2%). There were 32 (5%) q-wave myocardial infarctions, and 14 patients (2%) had transient low output syndrome. There was one episode of hypoperfusion corrected by lengthening the left ITA. Angiography for clinical indications in 27 patients 1 to 35 months postoperatively (mean, 9.5+/-8.3 months) demonstrated a distal anastomotic patency of 100% for ITA and 82% for radial artery grafts, concluded that complete arterial revascularization can be achieved with an ITA and radial artery T-graft with low operative risk and acceptable early patency. These results support the continued investigation of this grafting strategy (47). Van Dijk and colleagues (48) carried out a multicenter prospective trial on a cohort of 281 patients, with 139 patients randomly assigned to conventional coronary artery bypass grafting and 142 patients to OPCAB with a tissue stabilization system (Octopus Tissue Stabilization System; Medtronic; Minneapolis, MN), between March 1998 and August 2000, 281 patients were enrolled in 3 hospitals in the Netherlands, of whom 265 underwent treatment according to randomization. In 10 patients randomized to off-pump surgery, CPB was used during the procedure. One other patient randomized to off-pump surgery underwent coronary angioplasty because of infection. In 5 patients assigned to on-pump CABG, an off-pump procedure was performed. The results of their randomized trial indicate that there is no difference between off-pump and on-pump CABG in completeness of revascularization and cardiac outcome after 1 month. They concluded that CPB leads to reduced cardiac enzyme release, reduced use of blood products, and a slightly shorter hospital stay. Puskas and colleagues (12) in prospective trial randomized 200 unselected patients to CABG and CPB or OPCAB. They reported similar in-hospital and 30-day outcomes, similar completeness of revascularization - the number of grafts performed per patient (mean +/- SD 3.39 +/- 1.04 for off-pump coronary artery bypass grafting, 3.40 +/- 1.08 for conventional coronary artery bypass grafting) and the index of completeness of revascularization (number of grafts performed/number of grafts intended, 1.00 +/- 0.18 for off-pump coronary artery bypass grafting, 1.01 +/- 0.09 for conventional coronary artery bypass grafting) were similar. Likewise, the index of completeness of revascularization was similar between groups for the lateral wall, with shorter length of stay, reduced transfusion requirements, and less myocardial injury with OPCAB. Nathoe and colleagues (49) – Table 2 randomized 281 low-risk patients in prospective trial to CABG and CPB or OPCAB. No difference in cardiac outcome was observed at 1 year of follow-up. However, Off-pump surgery was more cost effective and may be regarded as an alternative to on-pump surgery. At one year, the total direct costs of on-pump surgery were 14.1 percent ($1,839) higher per patient than those of off-pump surgery ($14,908 vs. $13,069). Medication accounted for more than 50 percent of the follow-up costs. The absolute difference in the incidence of cardiovascular events (2.6 percent) implies that 38 patients must undergo on-pump surgery for 1 additional patient to be free of such events at one year. In terms of the difference in direct medical costs ($1,839 per patient), this result also implies an additional expenditure of approximately $70,000. Another randomized trial disclosed that off-pump surgery lowered hospital costs by 30 percent, mainly because of a reduction in perioperative morbidity and hospital stay (11). Three large meta-analyses (50, 51, 52) have reported that the mortality rate after OPCAB is comparable with that seen after CABG and CPB but that the duration of hospital stay is substantially reduced in patients who undergo OPCAB. Similar results were later found by several randomized controlled trials (53, 54, 55, 56). By reducing the morbidity rates associated with the procedure and decreasing the incidence of complications, the use of OPCAB has decreased the length of hospital stay (13). Khan and colleagues (57) randomized 104 patients to OPCAB or CABG with CPB and undertook postoperative coronary angiography at 3 months postoperatively. There were no deaths, and the OPCAB group had lower transfusion rates. In addition, they reported inferior patency rates with OPCAB, stating that the learning curve for this procedure is probably substantial and may be longer than anticipated. Clinical outcomes following CABG with CPB vs OPCAB have been compared in six main prospective randomized trials – Table 3 by Keenan and colleagues (58), in their review paper analyzing the current evidence comparing CABG and CPB with OPCAB. To date, five randomized controlled trials (11, 49, 54, 56, 59) have compared the economic outcomes of OPCAB with those of conventional CABG and CPB. All of these trials have found that OPCAB is less expensive than conventional CABG because of lower complication rates, shorter intubation times, and shorter stays in the intensive care unit and hospital for OPCAB patients. In a meta-analysis of the Beating Heart Against Cardioplegic Arrest Studies (BHACAS-1 and -2 studies) chest infection, inotropic requirement, incidence of arrhythmias, post-operative blood loss and consequent transfusion requirement, intubation time, intensive care unit stay and hospital length of stay were significantly lower in the off-pump group (32). Chamberlain and colleagues (60) recently investigated the incidence of early mortality and morbidity in a retrospective analysis of 1570 consecutive high-risk CABG-only patients. Using multivariate logistic regression analysis, OPCAB surgery was shown to result in reduced blood loss, transfusion requirement, intensive care unit, and hospital stay. Ascione and colleagues (61) compared OPCAB versus conventional CABG in overweight and obese patients and demonstrated that after adjustment for confounding factors, OPCAB was associated with significant reductions in early mortality, transfusion requirement, intensive care unit and hospital stay and neurological complications including stroke. Al-Ruzzeh and colleagues (62) in a randomised controlled clinical trial included 168 patients (27 women) requiring primary isolated coronary artery bypass grafting surgery, patients were randomised to conventional coronary artery bypass grafting surgery using cardiopulmonary bypass (n = 84) or OPCAB surgery (n = 84), carried out by one surgeon. MAIN OUTCOME MEASURES: Clinical outcome, graft patency at three months, neurocognitive functions at six weeks and six months, and health related quality of life. Their result showed that graft patency was evaluated by angiography in 151 (89.9%) patients and was similar between the cardiopulmonary bypass and off-pump groups (risk difference - 1%, 95% confidence interval - 5% to 4%), with the off-pump group considered the treatment group. Patients in the off-pump group required fewer blood transfusions (1.7 units v 1.0 unit, P = 0.02), shorter duration of mechanical ventilation (7.7 hours v 3.9 hours, P = 0.03), and shorter hospital stay (10.8 days v 8.9 days). Scores for neurocognitive function showed a significant difference in three memory subtests at six weeks and two memory subtests at six months in favour of the off-pump group. Patients in the off-pump group, however, needed a shorter stay in hospital, shorter duration of mechanical ventilation in the intensive therapy unit, and fewer blood transfusions, and had better preservation of neurocognitive function at six weeks and six months. El-Hamamsy, et al (63) reviews their long-term experience with the use of systematic OPCAB. This is a retrospective analysis of prospectively gathered data over an 8-year period (mean: 42±26 months) of patients systematically undergoing OPCAB surgery by a single surgeon (R.C.) at the Montreal Heart Institute. From January 1997 to December 2004, 1000 OPCAB surgeries were performed, representing the surgeon’s total OPCAB experience, reflecting the progression of OPCAB procedures compared with on-pump CABG through the years, exceeding 97% after 1998, with a 97% complete follow-up and was performed using phone and chart reviews. Early clinical outcome showed that overall operative mortality (30 days) was 1.6%. Three percent of patients had a perioperative MI (ST segment elevation: 2% and non-ST segment elevation: 1.3%). Mean levels of troponin I (48 hours) and CK-MB (24 hours) were, respectively, 0.3±0.9 ng/mL and 17±42 ng/mL. Transfusion of blood or blood-related products was necessary in 28% of patients (mean, 1.3 U/transfused patients). Atrial fibrillation was observed in 27% of patients. Eight patients (<1%) had a cerebrovascular accident. Mean hospital stay was 6.5±5.3 days. Overall actuarial survival at 1, 5, and 8 years is 96±1%, 88±1.5%, and 74±3%, respectively. Cardiac survival stands at 98±0.5%, 96±1%, 95±1.5% at 1, 5, and 8 years, respectively. Cardiac death included all patients with cardiac-related deaths or deaths of unknown causes. Angiographic studies were mainly performed in patients with adverse cardiac events (recurrent angina, MI, or CHF). One hundred eight patients underwent angiography over the follow-up period. Overall, 310 grafts were assessed (96 LAD, 94 circumflex arteries, 49 posterior descending arteries, 42 diagonals, and 29 right coronaries. The angiographic patency of various bypass grafts according to target vessels using the Fitzgibbon classification (64). Gobaly, internal thoracic artery (ITA) were patent in 96% (90% grade A and 6% grade B), vein graft in 75% (67% grade A and 8% grade B) and radial artery in 71% (all grade A). They concluded that complete coronary revascularization was accomplished in 95% of cases (average 3.2 grafts/patient). The worst patency rates were observed on the circumflex and posterior descending artery territories with occlusion rates of 23% and 35%, respectively, on long-term follow-up (63). Furthermore, as in this review, the increasing demands on healthcare resources worldwide should encourage us to use the more cost-effective therapies in the management of coronary disease. The BHACAS-1(11), Octopus (49) and Emory (56) trials demonstrated that OPCAB reduced perioperative costs by as much as 15–30%. In the BHACAS-1 study (11), this was attributed to the reduced cost of operating materials, bed occupancy, and transfusion requirements (total mean cost per patient: on-pump, $3731.6 ± 1169.7 versus off-pump, $2615.13 ± 953.6; P < 0.001). In addition to direct hospitalization and peri-operative costs, Nathoe and colleagues (49) calculated follow-up costs associated with repeat admissions for stroke, myocardial infarction or repeat revascularization procedures. The widespread acceptance of a new surgical technique depends on its reproducibility and on the feasibility of teaching the technique to the next generation of surgeons (65). Despite the apparent benefits of OPCAB surgery there is a lack of structured training programmes for OPCAB in the UK and elsewhere (65). A recent survey (66) from several cardiothoracic training centers in the United States demonstrated that only 22% of residents had performed 20 or more OPCAB procedures during their training, and only 12% had performed 20 or more complete myocardial revascularizations using OPCAB. Of these, only 4% had performed OPCAB circumflex coronary artery revascularization. Similar results (65) were obtained in a survey of cardiothoracic trainees in the UK where only coronary artery bypass grafting on the beating heart 2081 51% of UK trainees surveyed have experience of OPCAB in their training programme (GD Angelini, unpublished observations).

Conclusion

The present review demonstrates the safety and efficacy of OPCAB surgery. Off-pump revascularization is safe, reduces hospital cost, postoperative length of stay, and offers a practical solution to the increased costs and morbidity associated with conventional CABG. OPCAB is less expensive than conventional CABG due to lower complication rates, shorter intubation times, shorter stays in the ICU and hospital. The long-term patency rates will determine its overall efficacy. Therefore, with increasing follow-up periods, OPCAB surgery remains a viable and widely applicable surgical option for patients with coronary insufficiency.

References

1. Kolessov VI. Mammary artery-coronary artery anastomosis as method of treatment for angina pectoris. J Thorac Cardiovasc Surg 1967; 54:535–544.
2. Direct myocardial revascularization without extracorporeal circulation: experience in 700 patients. Chest 1991; 100:312–316.
3. Buffolo E, Silva de Andrade JC, Rodrigues Branco JN, Teles CA, Aguiar LF, Gomes WJ. Coronary artery bypass grafting without cardiopulmonary bypass. Ann Thorac Surg 1996;61:63–6.
4. Daly RC, Dearani JA, McGregor CG, et al. Fifty years of open heart surgery at the Mayo Clinic. Mayo Clin Proc. 2005 May;80(5):636-40
5. Kirklin JW, DuShane JW, Patrick RT, et al. Intracardiac surgery with the aid of a mechanical pump-oxygenator system (Gibbon type): report of eight cases. Proc Staff Meet Mayo Clin. 1955;30:201-206
6. Edmunds LH Jr. Extracorporeal perfusion. In: Edwards LH Jr, ed. Cardiac surgery in the adult. New York: McGraw-Hill, 1997:255–94.
7. Gott JP, Cooper WA, Schmidt FE Jr, et al. Modifying risk for extracorporeal circulation: trial of four anti-inflammatory strategies. Ann Thorac Surg 1998;66:747–54.
8. Nuttall GA, Erchul DT, Haight TJ, et al. A comparison of bleeding and transfusion in patients who undergo coronary artery bypass grafting via sternotomy with and without cardiopulmonary bypass. J Cardiothorac Vasc Anesth 2003;17:447–51.
9. Ereth MH, Nuttall GA, Oliver WC Jr, Santrach PJ, Price RD, Schaff HV. Temperature and duration of cardiopulmonary bypass influence transfusion requirements. J Clin Anesth 1998;10:588–92.
10. Jansen EW, Borst C, Lahpor JR, et al. Coronary artery bypass grafting without cardiopulmonary bypass using the octopus method: results in the first one hundred patients. J Thorac Cardiovasc Surg. 1998;116:60–67.
11. Ascione R, Lloyd CT, Underwood MJ, Lotto AA, Pitsis AA, Angelini GD. Economic outcome of off-pump coronary artery bypass surgery: a prospective randomized study. Ann Thorac Surg. 1999;68:2237–2242.
12. Puskas JD, Williams WH, Duke PG, et al. Off-pump coronary artery bypass grafting provides complete revascularization with reduced myocardial injury, transfusion and length of stay: a prospective randomized comparison of two hundred unselected patients undergoing off-pump versus conventional coronary artery bypass grafting. J Thorac Cardiovasc Surg 2003; 125:797–808.
13. Raja SG. Pump or No Pump for Coronary Artery Bypass. Current Best Available Evidence. Tex Heart Inst J. 2005; 32(4): 489–501.
14. Mojcik CF, Levy JH. Aprotinin and the systemic inflammatory response after cardiopulmonary bypass. Ann Thorac Surg 2001;71:745–54.
15. Paparella D, Yau TM, Young E. Cardiopulmonary bypass induced inflammation: pathophysiology and treatment. An update. Eur J Cardiothorac Surg 2002;21:232–44.
16. Casati V, Gerli C, Franco A, et al. Activation of coagulation and fibrinolysis during coronary surgery: on pump versus off pump techniques. Anesthesiology 2001; 95:1103–9.
17. Lytle BW, Loop FD, Cosgrove DM, et al. Fifteen hundred coronary reoperations. Results and determinants of early and late survival. J Thorac Cardiovasc Surg 1987;93:847–59.
18. Puskas JD, Wright CE, Ronson RS, Brown WM 3rd, Gott JP, Guyton RA .Off-pump multivessel coronary bypass via sternotomy is safe and effective. Ann Thorac Surg 1998;66:1068-1072.
19. Taggart DP, Westaby S. Neurological and cognitive disorders after coronary artery bypass grafting. Curr Opin Cardiol 2001;16:271–6.
20. Knipp SC, Matatko N, Wilhelm H, et al. Evaluation of brain injury after coronary artery bypass grafting. A prospective study using neuropsychological assessment and diffusion-weighted magnetic resonance imaging. Eur J Cardiothorac Surg 2004;25:791–800.
21. Kapetanakis EI, Stamou SC, Dullum MK, et al. The impact of aortic manipulation on neurologic outcomes after coronary artery bypass surgery: a risk-adjusted study. Ann Thorac Surg 2004;78:1564–71.
22. Hessel EA 2nd. Abdominal organ injury after cardiac surgery. Semin Cardiothorac Vasc Anesth 2004;8:243–63.
23. Tofukuji M, Stahl GL, Metais C, et al. Mesenteric dysfunction after cardiopulmonary bypass: role of complement C5a. Ann Thorac Surg 2000; 69:799–807.
24. Raja SG, Haider Z, Ahmad M. Predictors of gastrointestinal complications after conventional and beating heart coronary surgery. Surgeon 2003;1:221–8.
25. Conlon PJ, Stafford-Smith M, White WD, Newman MF, King S, Winn MP, et al. Acute renal failure following cardiac surgery. Nephrol Dialysis Transpl 1999;14:1158–62.
26. Leurs PB, Mulder AW, Fiers HA, Hoorntje SJ. Acute renal failure after cardiovascular surgery. Current concepts in pathophysiology, prevention and treatment. Eur Heart J 1989;10 Suppl H:38–42.
27. Hashimoto K, Miyamoto H, Suzuki K, et al. Evidence of organ damage after cardiopulmonary bypass. The role of elastase and vasoactive mediators. J Thorac Cardiovasc Surg 1992;104:666–73.
28. Ascione R, Lloyd CT, Underwood MJ, Gomes WJ, Angelini GD. On pump versus off pump coronary revascularization: evaluation of renal function. Ann Thorac Surg 1999;68:493–8.
29. Loef BG, Epema AH, Navis G, Ebels T, van Oeveren W, Henning RH. Off pump coronary revascularization attenuates transient renal damage compared with on pump coronary revascularization. Chest 2002;121:1190–4.
30. Hammon JW Jr, Edmunds LH Jr. Extracorporeal circulation: organ damage. In: Cohn LH, Edmunds LH Jr, editors. Cardiac surgery in the adult. 2nd ed. New York: McGraw-Hill Medical Pub; 2003. p. 361–88.
31. Downing SW, Savage EB, Streicher JS, Bogen DK, Tyson GS, Edmunds LH Jr. The stretched ventricle. Myocardial creep and contractile dysfunction after acute nonischemic ventricular distention. J Thorac Cardiovasc Surg 1992;104:996–1005.
32. Angelini GD, Taylor FC, Reeves BC, Ascione R. Early and midterm outcome after off pump and on pump surgery in Beating Heart Against Cardioplegic Arrest Studies (BHACAS 1 and 2): a pooled analysis of two randomised controlled trials. Lancet 2002;359:1194–9.
33. Zangrillo A, Landoni G, Sparicio D, et al. Predictors of atrial fibrillation after off-pump coronary artery bypass graft surgery. J Cardiothorac Vasc Anesth 2004;18:704–8.
34. Ascione R, Lloyd CT, Gomes WJ, Caputo M, Bryan AJ, Angelini GD. Beating versus arrested heart revascularization: evaluation of myocardial function in a prospective randomized study. Eur J Cardiothorac Surg 1999;15:685–90.
35. Penttilä HJ, Lepojärvi MV, Kiviluoma KT, Kaukoranta PK, Hassinen IE, Peuhkurinen KJ. Myocardial preservation during coronary surgery with and without cardiopulmonary bypass. Ann Thorac Surg 2001;71:565–71.
36. Louagie Y, Jamart J, Broka S, Collard E, Scavée V, Gonzalez M. .Off pump coronary artery bypass grafting: a case-matched comparison of hemodynamic outcome. Eur J Cardiothorac Surg 2002;22:552–8.
37. Piacenza AE, Cacheda JH, Badaracco JR, Benetti FJ. Troponin as a marker of myocardial damage during coronary surgery with and without cardiopulmonary bypass. J Cardiovasc Surg 2001;42:709–12.
38. Shenkman Z, Shir Y, Weiss YG, Bleiberg B, Gross D. The effects of cardiac surgery on early and late pulmonary functions. Acta Anaesthesiol Scand 1997;41:1193–9.
39. Staton GW, Williams WH, Mahoney EM, et al. Pulmonary outcomes of off-pump vs on-pump coronary artery bypass surgery in a randomized trial. Chest. 2005 Mar;127(3):892-901.
40. Benetti FJ, Ballester C, Sani G, Boonstra P, Grandjean J. Video assisted coronary bypass surgery. J Cardiac Surg 1995; 10:620–5.
41. Calafiore AM, Angelini GD, Bergsland J, Salerno TA. Minimally invasive coronary artery bypass grafting. Ann Thorac Surg 1996;62:1545– 8.
42. Subramanian VA, McCabe JC, Geller CM. Minimally invasive direct coronary artery bypass grafting: two-year clinical experience. Ann Thorac Surg 1997;64:1648 –55.
43. Borst C, Jansen EW, Tulleken CA, et al. Coronary artery bypass grafting without cardiopulmonary bypass and without interruption of native coronary flow using a novel anastomosis site restraining device (“Octopus”). J Am Coll Cardiol. 1996;27:1356 –1364.
44. Oliveira PP, Braile DM, Vieira RW, et al. Hemodynamic disorders related to beating heart surgery using cardiac stabilizers: experimental study. Rev Bras Cir Cardiovasc. 2007 Dec;22(4):407-15
45. Hart JC, Spooner TH, Pym J, et al. A review of 1,582 consecutive Octopus off-pump coronary bypass patients. Ann Thorac Surg 2000;70:1017-1020.
46. Puskas JD, Thourani VH, Marshall JJ, et al. Clinical outcomes, angiographic patency, and resource utilization in 200 consecutive off-pump coronary bypass patients. Ann Thorac Surg 2001;71:1477-1484.
47. Sundt TM III, Barner HB, Gay, WA. Total arterial revascularization with an internal thoracic artery and radial T graft. Ann Thorac Surg 1999;68:399–405.
48. van Dijk D, Nierich AP, Jansen EW, et al. Early outcome after off-pump versus on-pump coronary artery bypass surgery: results from a randomized study. Circulation 2001; 104:1761–1766.
49. Nathoe HM, van Dijk D, Jansen EW, et al. A comparison of on-pump and off-pump coronary bypass surgery in low-risk patients. N Engl J Med 2003; 348:394–402.
50. Reston JT, Tregear SJ, Turkelson CM. Meta-analysis of short-term and mid-term outcomes following off-pump coronary artery bypass grafting. Ann Thorac Surg 2003;76:1510–5.
51. Parolari A, Alamanni F, Cannata A, et al. Off-pump versus on-pump coronary artery bypass: meta-analysis of currently available randomized trials. Ann Thorac Surg 2003;76:37–40.
52. van der Heijden GJ, Nathoe HM, Jansen EW, Grobbee DE. Meta-analysis on the effect of off-pump coronary bypass surgery. Eur J Cardiothorac Surg 2004;26:81–4.
53. Légaré JF, Buth KJ, King S, et al. Coronary bypass surgery performed off pump does not result in lower in-hospital morbidity than coronary artery bypass grafting performed on pump. Circulation 2004;109:887–92.
54. Straka Z, Widimsky P, Jirasek K, et al. Off-pump versus on-pump coronary surgery: final results from a prospective randomized study PRAGUE-4. Ann Thorac Surg 2004;77:789–93.
55. Gerola LR, Buffolo E, Jasbik W, et al. Off-pump versus on-pump myocardial revascularization in low-risk patients with one or two vessel disease: perioperative results in a multicenter randomized controlled trial. Ann Thorac Surg 2004;77:569–73.
56. Puskas JD, Williams WH, Mahoney EM, et al. Off-pump vs conventional coronary artery bypass grafting: early and 1-year graft patency, cost, and quality-of-life outcomes: a randomized trial. JAMA 2004;291:1841–9.
57. Khan NE, De Souza A, Mister R, et al. A randomized comparison of off-pump and on-pump multivessel coronary artery bypass surgery. N Engl J Med 2004; 350:21–28
58. Keenan TD, Abu-Omar Y, Taggart DP, Bypassing the Pump: Changing Practices in Coronary Artery Surgery. Chest 2005;128;363-369.
59. Lee JD, Lee SJ, Tsushima WT, et al. Benefits of off-pump bypass on neurologic and clinical morbidity: a prospective randomized trial. Ann Thorac Surg 2003;76:18–26.
60. Chamberlain MH, Ascione R, Reeves BC, Angelini GD. Effectiveness of coronary artery bypass grafting in high-risk patients: an observational study. Ann Thorac Surg 2002;73:1866–73.
61. Ascione R, Reeves BC, Rees K, Angelini GD. Effectiveness of coronary artery bypass grafting with or without cardiopulmonary bypass in overweight patients. Circulation 2002;106:1764–70.
62. Al-Ruzzeh S, George S, Bustami M, et al. Effect of off-pump coronary artery bypass surgery on clinical, angiographic, neurocognitive, and quality of life outcomes: randomised controlled trial. BMJ. 2006 June 10; 332(7554): 1365.
63. El-Hamamsy I, Cartier R, Demers P, Bouchard D, Pellerin M. Long-Term Results After Systematic Off-Pump Coronary Artery Bypass Graft Surgery in 1000 Consecutive Patients. Circulation 2006; 114; I-486-I-491.
64. Fitzgibbon GM, Burton JR, Leach AJ. Coronary bypass graft fate: angiographic grading of 1400 consecutive grafts early after operation and of 1132 after one year. Circulation. 1978; 57: 1070–1074.
65. Murphy GJ, Ascione R, Angelini GD. Coronary artery bypass grafting on the beating heart: surgical revascularization for the next decade? Eur Heart J. 2004 Dec, 25(23):2077-85.
66. Ricci M, Karamanoukian HL, D’Ancona G. Survey of resident training in beating heart operations. Ann Thorac Surg 2000;70:479–82.

Author Information

Emad M. Hijazi, MD
Division of Cardiac Surgery, Department of General Surgery (8C), Princess Muna AL-Hussein Cardiac Center. King Abdullah University Hospital – Faculty of Medicine / Jordan University of Science and Technology - Jordan-Irbid

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