Hemodynamic collapse during off-pump coronary artery bypass grafting

Inhaled iloprost in off-pump coronary artery bypass surgery: a randomized controlled trial

PURPOSE

Mechanical cardiac constraint during off-pump coronary artery bypass surgery (OPCAB) causes right ventricle (RV) compression and increased pulmonary artery pressure (PAP), which may further compromise RV dysfunction. We aimed to assess the effect of inhaled iloprost, a potent selective pulmonary vasodilator, on the cardiac index (CI) during mechanical constraint. The secondary aim was to determine the resultant changes in the hemodynamic and respiratory parameters.

METHODS

A total of 100 adult patients with three-vessel coronary artery disease who had known risk factors for hemodynamic instability (congestive heart failure, mean PAP ≥ 25 mm Hg, RV systolic pressure ≥ 50 mm Hg on preoperative echocardiography, left ventricular ejection fraction < 50%, myocardial infarction within one month of surgery, redo surgery, and left main disease) were enrolled in a randomized controlled trial. The patients were randomly allocated to the control or iloprost groups at a 1:1 ratio, in which saline and iloprost (20 μg) were inhaled for 15 min after internal mammary artery harvesting, respectively. Cardiac index was measured by pulmonary artery catheterization.

RESULTS

There were no significant intergroup differences in CI during grafting (P = 0.36). The mean PAP had a significant group-time interaction (P = 0.04) and was significantly lower in the iloprost group at circumflex grafting (mean [standard deviation], 26 [3] mm Hg vs 24 [3] mm Hg; P = 0.01). The remaining hemodynamic parameters were similar between the groups.

CONCLUSION

Inhaled iloprost showed a neutral effect on hemodynamic parameters, including the CI and pulmonary vascular resistance index, during OPCAB.

TRIAL REGISTRATION

ClinicalTrials.gov (NCT04598191); first submitted 12 October 2020.

Off-Pump Coronary Artery Bypass Grafting; is it Still Relevant?

Off-pump Coronary Artery Bypass Grafting (OPCAB) experienced a resurgence in the 1980s -2000s and developed steadily with improvement of the instrumentation and techniques. However questions about graft patency and long-term survival of OPCAB patients still exist. This review attempts to explore the current relevance of OPCAB.

Prophylactic intra-aortic balloon pump in patients with left main disease undergoing off-pump coronary artery bypass grafting

Background

Preventive intra-aortic balloon pump (IABP) for high-risk patients with stable hemodynamics is controversial, and its definition of high-risk is still unclear. This study aimed to investigate the effect of prophylactic IABP on the early outcome of left main disease (LMD) patients receiving off-pump coronary artery bypass grafting (OPCABG) with stable hemodynamics.

Methods

From January 2013 to April 2020, 257 consecutive patients who underwent OPCABG through sternotomy were enrolled in this study. All LMD patients (greater than 70%) had stable hemodynamics (BP>100 mmHg without vasoconstrictor substance infusion). Early outcomes of 125 patients with prophylactic IABP (IABP group) and 132 patients without IABP (Control group) were compared in this study.

Results

IABP did not show favorable effect on the conversion to CPB (RR 0.63, 95%CI 0.05–7.89, P = 0.7211), perioperative MI (RR 0.69, 95%CI 0.22–2.12, P = 0.5163), mortality (RR 0.65, 95%CI 0.04–10.25, P = 0.7608) or the composite end of the conversion, MI and mortality (RR 0.63, 95%CI 0.23–1.74, P = 0.3747). There was greater incidence of prolonged ventilation in IABP after adjustment (RR2.16, 95%CI 1.12–4.18, P = 0.0221). There was no IABP-related mortality or limb ischemia.

Conclusion

No significant difference in early outcomes was observed in hemodynamically stable patients with LMD between prophylactic IABP group and control group. Prophylactic IABP may be unnecessary in patients with LMD undergoing OPCABG.

Early outcomes in patients undergoing off-pump coronary artery bypass grafting

Background

In spite of general decline worldwide, off-pump coronary artery bypass grafting (CABG) surgery is performed in more than 60% of patients undergoing CABG in India; mainly because of shorter operative time and reduced procedure cost. However, paucity of data exists in literature about early outcomes following off-pump CABG from India.

Methodology

We conducted a prospective observational study of 800 consecutive cases that underwent off-pump CABG (OPCAB) from August 2015 to October 2017. Primary end point of the study was the 30-day/in-hospital mortality from any cause.

Results

On multivariate analysis, emergency surgery (OR 9.72; CI 1.96-48.21, p value 0.005), severe left ventricular dysfunction (OR 2.28; CI 1.25-4.76, p value 0.026), postoperative atrial fibrillation (OR 9.95; CI 3.12-32.01, p value 0.05), and dialysis-dependent renal failure (OR 29.7, CI 10.02-87.99, p value 0.006) were the factors associated with mortality. The observed mortality was 1.6%, and the expected mortality by EuroSCORE II was 2.6%. The median EuroSCORE II of expired patients was 3.03 and of entire cohort was 1.54 (p value 0.001). Stroke rate was 0.9%. Deep sternal wound infection occurred in 0.9%, and 3.8% patients were readmitted to the hospital after discharge.

Conclusion

Early outcome of off-pump CABG was excellent in this study. Increased incidence of deep sternal wound infection remains a concern. Multicenter study with a larger sample size is required for a dependable evaluation of the efficacy of off-pump CABG in Indian population.

Conversion after off-pump coronary artery bypass grafting: the CORONARY trial experience

Objectives

Emergent and late conversions form OFF-to-ON pump coronary artery bypass grafting (CABG) have been associated with worse outcomes, however, it remains unclear as to which risk factors are associated with conversion and how to prevent them.

Methods

Among 4718 patients who randomly underwent off- or on-pump CABG, the incidence of off-pump to on-pump cross-over, or 'OFF-to-ON conversion', was 7.9% (186/2356). The primary outcome was a composite of death, stroke, myocardial infarction, or new renal failure requiring dialysis. We assessed the risk factors and outcomes of converted patients.

Results

Emergent OFF-to-ON conversions, defined as conversions for hypotension or ischaemia, were required for 3.2% of patients ( n  = 75), while most elective conversions were due to small or intramuscular coronaries ( n  = 83). OFF-to-ON converted patients required increased surgery time, blood transfusions, intensive care unit stay, and presented a higher incidence at 1 year of the composite outcome compared with non-converted off-pump patients (all P < 0.01), especially if the conversion was emergent. Conversely, elective conversions outcomes were no different compared with non-converted off-pump patients ( P  = 0.35). Independent predictors of emergent conversions included higher heart rate or chronic atrial fibrillation, urgent surgery, more grafts planned and surgeon experience with off-pump CABG.

Conclusions

Emergent OFF-to-ON conversion is associated with worse outcomes compared with elective conversion or no conversion. In the presence of risk factors for emergent conversion, an early and elective conversion approach is a judicious strategy.

Risk Factors of On-Pump Conversion during Off-Pump Coronary Artery Bypass Graft

Background

Off-pump coronary artery bypass grafting (OPCABG) procedures can avoid the complications of an on-pump bypass. However, some cases unexpectedly require conversion to cardiopulmonary bypass during OPCABG. The risk factors associated with a sudden need for cardiopulmonary bypass were analyzed.

Methods

This retrospective study included 283 subjects scheduled for OPCABG from 2001 to 2010. These were divided into an OPCABG group and an on-pump conversion group. Preoperative, operative, and postoperative variables were compared between the 2 groups.

Results

Of the 283 patients scheduled for OPCABG, 47 (16%) were switched to on-pump coronary artery bypass grafting (CABG). The mortality of the both the OPCABG and on-pump conversion groups was not significantly different. The major risk factors for conversion to on-pump CABG were congestive heart failure (CHF) (odds ratio [OR], 3.5; p=0.029), ejection fraction (EF) <35% (OR, 4.4; p=0.012), and preoperative beta-blocker (BB) administration (OR, 0.3; p=0.007). The use of intraoperative (p=0.007) and postoperative (p=0.021) inotropics was significantly higher in the conversion group. The amount of postoperative drainage (p<0.001) and transfusion (p<0.001) also was significantly higher in the conversion group. There were no significant differences in stroke or cardiovascular complications between the groups over the course of short-term and long-term follow-up.

Conclusion

Patients who undergo OPCABG and have CHF or a lower EF (<35%) are more likely to undergo on-pump conversion, while preoperative BB administration could help prevent conversions from OPCABG to on-pump CABG.

Myocardial revascularization without extracorporeal circulation; Why hasn't it convinced yet?

Extracorporeal circulation has led to a great development in cardiovascular surgery during the last five decades. Its time-proven efficacy and safety have made on-pump coronary artery bypass grafting (CABG) the gold standard method of surgical revascularization. However, coronary revascularization on cardiopulmonary bypass and the accompanying aortic manipulation are related to plenty of deleterious complications. Therefore, off-pump CABG surgery was established to avoid complications. Nevertheless, despite the initial enthusiasm on this technique, only 20% of myocardial revascularization procedures worldwide are performed off-pump. Not only are off-pump cardiac procedures more technically difficult but also they do not provide better results in terms of graft patency, completeness of revascularization, repeat revascularization requirement, cost, and quality of life. Completeness of revascularization and anastomotic quality should not be compromised to avoid cardiopulmonary bypass.

Off-pump coronary artery bypass: past, present and future of a controversial technology

PURPOSE OF REVIEW

This review will examine the current role of off-pump coronary artery bypass (OPCAB) surgery compared with on-pump coronary artery bypass (ONCAB) surgery for the revascularization of ischemic myocardium.

RECENT FINDINGS

Recent studies have confirmed earlier findings that OPCAB is associated with less grafts per patient and less complete revascularization, and increased incidence of recurrent angina and need for repeat revascularization procedures, and more frequent rehospitalization for cardiac-related issues. OPCAB does not prevent postoperative renal dysfunction and is associated with worse long-term outcomes. Hospital costs are not reduced and are increased in those OPCAB patients who require intraoperative conversion to ONCAB procedures; however, when multiple arterial grafts are used and a complete revascularization is performed, OPCAB outcomes are equivalent to those of ONCAB procedures.

SUMMARY

OPCAB should only be performed by surgeons experienced in this technique in patients in whom a complete revascularization can be achieved; preferably with multiple arterial grafts.

Off-Pump Coronary Artery Bypass Surgery: Analysis of 5-Year Experience

We retrospectively evaluated the perioperative results of off-pump coronary artery bypass surgery performed in our center. Over a 5-year period, 520 patients were operated off-pump through a median sternotomy with the aid of a cardiac stabilizer and retractor. A total of 1,117 distal anastomoses were made with a mean of 2.2 ± 1.0 bypass grafts per patient. Only 12 patients (2.3%) required conversion to cardiopulmonary bypass, while 10 patients (1.9%) were re-operated for bleeding or graft failure. Perioperative myocardial infarction occurred in 10 patients (1.9%), and postoperative stroke in 3 patients (0.6%). The overall operative mortality was 2.5%, while the rate for the 48 patients who had previous bypass surgery was 2.1%. The results show that off-pump coronary surgery produces low mortality and morbidity, even in the treatment of multivessel disease or high-risk patients.

Preoperative Prophylactic Intraaortic Balloon Pump Reduces the Incidence of Postoperative Acute Kidney Injury and Short-Term Death of High-Risk Patients Undergoing Coronary Artery Bypass Grafting: A Meta-Analysis of 17 Studies

This meta-analysis investigated the effects of preoperative prophylactic intraaortic balloon pump placement on postoperative renal function and short-term death of high-risk patients undergoing coronary artery bypass grafting. We found that preoperative prophylactic intraaortic balloon pump support reduced the incidence of coronary artery bypass grafting-associated acute kidney injury and short-term death and dramatically decreased the incidence of postoperative renal replacement therapy by 82% compared with high-risk patients without the procedure. This is the first meta-analysis to demonstrate significant beneficial effects of preoperative prophylactic intraaortic balloon pump on renal function in high-risk patients undergoing coronary artery bypass grafting.

Short-term response of metabolic hormones to coronary artery bypass surgery

PURPOSE

To explore the response pattern of plasma adipokine and ghrelin levels to coronary artery bypass graft (CABG) surgery in patients with (on-pump) and without (off-pump) cardiopulmonary bypass (CPB).

MATERIAL/METHODS

Sixteen consecutive patients (age: 62 ± 10 years, male: 10) with obstructive coronary artery disease (CAD) who underwent elective CABG surgery with CPB and intraoperative GIK infusion were selected for on-pump group and 19 CAD patients (age: 63 ± 10 years, male: 16) were included in the off-pump group. Blood samples were taken before, during and after surgery. Intraoperative samples were withdrawn simultaneously for peripheral vein and sinus coronarius (SC). Plasma adipokine concentrations were measured by ELISA, those of ghrelin by RIA kits.

RESULTS

In response to surgical intervention there was an early, transient fall in plasma levels of adiponectin (p<0.0001) and resistin (p=0.002) followed by an increase to approach their initial values. Plasma ghrelin also increased (p=0.045), this increase, however, was confined to the period of GIK supported CPB. Plasma insulin (p=0.003) and resistin (p=0.009) was significantly higher in the peripheral vein than in SC. The perioperative hormone profile of patients without CPB (off-pump) proved to be comparable to that of on-pump patients in spite of the insulin administration and greater oxidative and inflammatory stress.

CONCLUSIONS

Adipose tissue-derived factors appear to mediate the metabolic and vascular changes that occur in patients with CABG surgery. Epicardial adipose tissue is unlikely to have major contribution to the development of CAD as adipokines are not elevated in SC independent of the mode of intervention.

A novel coronary active perfusion system using a conventional intra-aortic balloon pump for off-pump coronary artery bypass grafting

OBJECTIVE

It is important for coronary active perfusion systems to avoid myocardial ischemia during off-pump coronary artery bypass grafting. We have developed a new concept for a perfusion system to pump blood based on changes in helium gas volume. This system uses a conventional intra-aortic balloon pump to activate the perfusion pump. Our study used basic and animal experiments to investigate the most suitable system for coronary perfusion using this new concept.

METHODS

A conventional intra-aortic balloon pump was used to supply power. A device for perfusion was developed with a balloon placed inside a stiff syringe barrel. The device was connected to the helium gas line of the intra-aortic balloon pump. Changes in flow with changes in augmentation level were noted when volumes outside and within the balloon were changed. Six pigs with occlusion of the left anterior descending artery were used for system validation, with monitoring to identify changes in hemodynamics and cardiac enzyme levels.

RESULTS

In the basic experiment, an 80-mL outside volume and 3.0-mL inner volume resulted in the greatest percentage change in flow rate with respect to changes in augmentation. In the animal experiment, the new coronary active perfusion system prevented myocardial ischemia during coronary occlusion.

CONCLUSIONS

We clarified the most suitable method for our new coronary active perfusion system. Using this system, safe anastomosis was consistently performed in animal experiments. Clinically, off-pump coronary artery bypass may potentially be performed more safely and easily using this new system.

On-pump beating-heart versus conventional coronary artery bypass grafting for revascularization in patients with severe left ventricular dysfunction: early outcomes

BACKGROUND

We sought to evaluate the effects of on-pump beating-heart versus conventional coronary artery bypass grafting techniques requiring cardioplegic arrest in patients with coronary artery disease with left ventricular dysfunction.

METHODS

We report the early outcomes associated with survival, morbidity and improvement of left ventricular function in patients with low ejection fraction who underwent coronary artery bypass grafting between August 2009 and June 2012. Patients were separated into 2 groups: group I underwent conventional coronary artery bypass grafting and group II underwent an on-pump beating-heart technique without cardioplegic arrest.

RESULTS

In all, 131 patients underwent coronary artery bypass grafting: 66 in group I and 65 in group II. Left ventricular ejection fraction was 26.6% ± 3.5% in group I and 27.7% ± 4.7% in group II. Left ventricular end diastolic diameter was 65.6 ± 3.6 mm in group I and 64.1 ± 3.2 mm in group II. There was a significant reduction in mortality in the conventional and on-pump beating-heart groups (p < 0.001). Perioperative myocardial infarction and low cardiac output syndrome were higher in group I than group II (both p < 0.05). Improvement of left ventricular function after the surgical procedure was better in group II than group I.

CONCLUSION

The on-pump beating-heart technique is the preferred method for myocardial revascularization in patients with left ventricular dysfunction. This technique may be an acceptable alternative to the conventional technique owing to lower postoperative mortality and morbidity.

Off-pump coronary revascularization: A potential benefit for female patients?

Coronary artery disease is one of the leading causes of illness for both men and women. However, women are 3 times more likely to die for coronary artery disease as they are of breast cancer. There are an increasing prevalence of coronary artery disease in women and thus facing the need for surgical revascularization. It has long being accepted that women carry a high risk of coronary surgery than men. Many investigators have suggested that female itself is predictive of poor outcome after on pump coronary surgery. We thought to search the litlature to investigate whether women who undergo off-pump surgery receive any benefits compared with women undergoing on-pump surgery.

Increasing Surgical Experience with Off-Pump Coronary Surgery Does Not Mitigate the Morbidity of Emergency Conversion to Cardiopulmonary Bypass

Objective

Emergency conversion during off-pump coronary artery bypass (OPCAB) confers significant morbidity. We sought to determine whether the outcomes in these patients have changed as our experience with off-pump techniques has increased.

Methods

Between January 1999 and December 2010, 4763 patients underwent coronary artery surgery. An off-pump strategy was attempted in 4415 cases (92.7%). The results of the most recent 50 patients who required emergency conversion were compared with the preceding 50 conversions and with patients who underwent either OPCAB (n = 2737) or on-pump coronary surgery (coronary artery bypass grafting) (n = 268) during the same time frame.

Results

The emergency conversion rate was 2.27% (n = 100), being 2.97% for the first 50 cases and 1.77% for the subsequent 50 patients. The two sequential groups of emergency conversions had similar indications and timing of conversion and comparable outcomes. When compared with patients who underwent OPCAB, the more recent 50 conversions had higher mortality (P = 0.002) and more frequent sternal wound infection (P = 0.036), hemorrhage requiring reoperation (P = 0.003), respiratory failure (P < 0.0001), and all-cause sepsis (P = 0.001). Compared with the on-pump group, the more recent conversions had higher mortality (P = 0.055) and a greater rate of postoperative sepsis (P = 0.002).

Conclusions

The incidence of emergency conversion during OPCAB has decreased with increasing surgical experience; however, the morbidity in these patients remains essentially unchanged. The outcomes in these patients remain worse than those in nonconverted patients. Safer bailout strategies during OPCAB are still warranted.

Cardiac displacement-induced hemodynamic instability during off-pump coronary artery bypass surgery and its predictors

BACKGROUND

Emergent conversion to an on-pump procedure during an off-pump coronary artery bypass surgery (OPCAB) due to hemodynamic instability is associated with increased morbidity and mortality. The aim of this study was to evaluate the predictors of hemodynamic instability associated with mechanical heart displacement during OPCAB and the fate of these patients.

METHODS

Data of 494 patients who underwent elective, isolated OPCAB between December 2006 and April 2010 were reviewed. Hemodynamic instability was defined as mixed venous oxygen saturation (SvO(2) ) <60% during grafting. Pre-operative variables including the presence of diastolic dysfunction and mitral regurgitation (MR) were evaluated for their predictive value for hemodynamic instability by logistic regression analysis. Outcome variables were also compared between patients who developed hemodynamic instability and those who did not.

RESULTS

In univariate analysis, body mass index, diabetes mellitus, chronic obstructive pulmonary disease (COPD), left ventricular ejection fraction, diastolic dysfunction, MR ≥ grade 1, higher creatinine and the use of diuretics were identified as risk factors. In multivariate analysis of these variables, COPD and creatinine remained as independent risk factors for hemodynamic instability. These patients also had significantly lower cardiac output and SvO(2) after sternum closure and a higher incidence of composite morbidity end points.

CONCLUSION

COPD and pre-operative creatinine level were identified as independent risk factors of mechanical heart displacement-induced hemodynamic instability during OPCAB. As these patients were associated with significantly lower SvO(2) even at the end of surgery and with adverse outcome, consideration may be given to initiate preemptive measures to increase SvO(2) before or during grafting.

On-pump versus off-pump coronary-artery bypass surgery

BACKGROUND

Coronary-artery bypass grafting (CABG) has traditionally been performed with the use of cardiopulmonary bypass (on-pump CABG). CABG without cardiopulmonary bypass (off-pump CABG) might reduce the number of complications related to the heart-lung machine.

METHODS

We randomly assigned 2203 patients scheduled for urgent or elective CABG to either on-pump or off-pump procedures. The primary short-term end point was a composite of death or complications (reoperation, new mechanical support, cardiac arrest, coma, stroke, or renal failure) before discharge or within 30 days after surgery. The primary long-term end point was a composite of death from any cause, a repeat revascularization procedure, or a nonfatal myocardial infarction within 1 year after surgery. Secondary end points included the completeness of revascularization, graft patency at 1 year, neuropsychological outcomes, and the use of major resources.

RESULTS

There was no significant difference between off-pump and on-pump CABG in the rate of the 30-day composite outcome (7.0% and 5.6%, respectively; P=0.19). The rate of the 1-year composite outcome was higher for off-pump than for on-pump CABG (9.9% vs. 7.4%, P=0.04). The proportion of patients with fewer grafts completed than originally planned was higher with off-pump CABG than with on-pump CABG (17.8% vs. 11.1%, P<0.001). Follow-up angiograms in 1371 patients who underwent 4093 grafts revealed that the overall rate of graft patency was lower in the off-pump group than in the on-pump group (82.6% vs. 87.8%, P<0.01). There were no treatment-based differences in neuropsychological outcomes or short-term use of major resources.

CONCLUSIONS

At 1 year of follow-up, patients in the off-pump group had worse composite outcomes and poorer graft patency than did patients in the on-pump group. No significant differences between the techniques were found in neuropsychological outcomes or use of major resources. (ClinicalTrials.gov number, NCT00032630.).

Minimal extracorporeal circulation: an alternative for on-pump and off-pump coronary revascularization

BACKGROUND

Coronary artery bypass surgery employing minimal extracorporeal circulation (MECC) was compared with standard extracorporeal circulation (ECC) and off-pump coronary artery bypass graft surgery (OPCABG) with regard to the perioperative course.

METHODS

From January 2004 to December 2007, 1,674 patients (n = 558 MECC, n = 558 ECC, n = 558 OPCABG) who underwent coronary bypass surgery were studied. The primary end point was in-hospital mortality; secondary end points were perioperative variables, intensive care, and in-hospital course.

RESULTS

Demographic data, comorbidity, and the European System for Cardiac Operative Risk Evaluation score (MECC 3.0%, ECC 3.5%, OPCABG 3.2%) were similar among the groups, but in-hospital mortality for elective and urgent/emergent patients was lower in the MECC and OPCABG groups (MECC 3.2%, OPCABG 3.7%, ECC 6.9%; p < 0.05). The number of distal anastomoses was lowest in the OPCABG group, but comparable for MECC and ECC patients. Postoperative ventilation time, release of creatinine kinase, catecholamine therapy, drainage loss, and transfusion requirements were lower in the MECC and OPCABG groups, whereas stay in the intensive care unit was shorter only in the latter (p < 0.05).

CONCLUSIONS

Minimal extracorporeal circulation is an easy and safe procedure for coronary artery bypass graft surgery. In selected patients, the advantages of MECC equal those of OPCABG. MECC should be considered as an alternative to OPCABG and standard ECC procedures.

Relationship between echocardiographic index of ventricular filling pressure and intraoperative haemodynamic changes during off-pump coronary bypass surgery

BACKGROUND

The ratio of mitral velocity to early-diastolic velocity of the mitral annulus (E/e') is an indicator of diastolic function representing acute loading conditions of the left ventricle. We tested the efficacy of E/e' as a predictor of haemodynamic derangement during off-pump coronary artery bypass surgery (OPCAB), when heart displacement causes loading changes.

METHODS AND RESULTS

Fifty patients with left ventricular (LV) ejection fraction >or= 50% were divided into two groups; E/e'<8 (normal LV filling pressure, n=25) and >15 (increased LV filling pressure, n=25). Haemodynamic measurements were recorded after induction of anaesthesia, during grafting, and after sternum closure. Patients' characteristics and operative data were similar between the groups. Cardiac index and mixed venous oxygen saturation were significantly lower during grafting and after sternum closure in the E/e'>15 group, compared with E/e'<8 group and with the baseline values. The E/e'>15 group required significantly longer ventilation time and length of stay in the intensive care unit.

CONCLUSIONS

Even in patients with preserved systolic LV function, patients with E/e'>15 were more prone to undergo a significant decrease in cardiac output during OPCAB, which did not return to baseline level after completion of grafting. Whether this finding is associated with increased morbidity and mortality should be validated.

Effect of intracoronary shunt on right ventricular function during off-pump grafting of dominant right coronary artery with poor collateral

Although numerous studies have validated the efficacy of intracoronary shunt on reducing left ventricular dysfunction during off-pump coronary artery bypass surgery (OPCAB), there is lack of evidence supporting its role on right ventricular (RV) function during right coronary artery (RCA) revascularization. Therefore, we studied the effect of intracoronary shunt during grafting of dominant RCA without visible collateral supply on global RV function using thermodilution method. Forty patients scheduled for multivessel OPCAB with right dominant coronary circulation without collateral supply confirmed by angiography were randomized to RCA revascularization either with a shunt (n=20) or soft snare occlusion (n=20). RV ejection fraction (RVEF) was recorded at baseline, during RCA grafting, and 15 min after reperfusion. Corresponding RV stroke work index (RVSWI) was calculated. RVEF and RVSWI decreased significantly during RCA grafting and returned to baseline values after reperfusion in both groups without any significant differences between the groups. Intracoronary shunt did not exert any beneficial effect on global RV function during RCA grafting, even in the absence of visible collateral supply. Regarding the possibility of graft failure by intracoronary shunt-induced endothelial damage, routine use of intracoronary shunt during RCA grafting is not recommended in patients with preserved biventricular function.

Predictors of Emergency Conversion to On-Pump during Off-Pump Coronary Surgery

The purpose of this study was to determine predictors and evaluate outcomes of emergency conversion to cardiopulmonary bypass during planned off-pump coronary artery bypass grafting. From January 2001 to November 2005, of 467 consecutive patients aged ≥ 60 years who underwent off-pump coronary surgery, 17 (3.6%) were converted to cardiopulmonary bypass. Those converted to an on-pump technique had significantly higher rates of postoperative cerebrovascular accident (17.6% vs 1.1%), intraaortic balloon pumping (5.9% vs 0%), and red blood cell transfusion (82.4% vs 57.3%), as well as prolonged intensive care unit stay (52.9% vs 25.2%), ventilation time (25% vs 5.3%) and hospital stay (64.7% vs 31.3%) compared to patients whose operation was completed off-pump. Multivariable logistic regression identified left ventricular ejection and left main stenosis as significantly associated with conversion. The rate of emergency conversion to cardiopulmonary bypass during planned off-pump coronary surgery was acceptable, but patients who required conversion had less favorable early outcomes than those who remained off-pump.

On-Pump Beating-Heart Coronary Artery Bypass: A Propensity Matched Analysis

BACKGROUND

It remains unclear how cardioplegic arrest affects surgical results after coronary artery bypass grafting surgery (CABG). This study compares early outcomes after on-pump beating-heart CABG and conventional CABG.

METHODS

From 2002 to 2005, 114 patients underwent on-pump beating-heart CABG. Multivariate logistic regression revealed five characteristics according to which technique is liable to be used: history of cerebral infarction, urgent or emergent operation, lower ejection fraction, preoperative creatine kinase, and lower number of diseased vessels. The early clinical outcome for these patients was compared against 114 conventional CABG patients, matched using a propensity score constructed with these five significant variables and with two nonsignificant variables: history of diabetes mellitus and hypertension.

RESULTS

On-pump beating-heart CABG significantly reduced the duration of operation and cardiopulmonary bypass, total blood loss, and peak creatine kinase (p < 0.05). The number of patients requiring additional intra-aortic balloon pump support was significantly lower in the on-pump beating-heart CABG group (2 versus 13, p < 0.01). No patients required percutaneous cardiopulmonary support after on-pump beating-heart CABG, whereas 4 patients needed it after conventional CABG. Complete revascularization was significantly lower (42.1% versus 77.2%, p < 0.0001), but in-hospital mortality was less in the on-pump beating-heart CABG group (2.6% versus 9.6%, p < 0.05). No significant difference was found in morbidity including stroke, renal failure, mediastinitis, and prolonged ventilation.

CONCLUSIONS

On-pump beating-heart CABG can be performed safely, including on high-risk patients. Use of cardiopulmonary bypass and the elimination of cardioplegic arrest may be of most benefit to hemodynamically unstable patients.

Deleterious effects of cardiopulmonary bypass in coronary artery surgery and scientific interpretation of off-pump's logic

Cardiopulmonary bypass (CPB) has been suggested to be a cause of complex systemic inflammatory response that significantly contributes to several adverse postoperative complications. In the last few years, off-pump coronary artery bypass grafting (OPCAB) has gained widespread attention as an alternative technique to conventional on-pump coronary artery bypass grafting (ONCAB). However, a degree of uncertainty regarding the relative merits of ONCAB and OPCAB continues to be a significant issue. Surgeons supporting off-pump surgery, state that the avoidance of the CPB leads to significantly reduced myocardial ischemia-reperfusion injury, postoperative systemic inflammatory response and other biological derangements, a feature that may improve the clinical outcomes. However, perfection in perioperative care, surgical technique and methods of attenuating the untoward effects of CPB has resulted in better clinical outcome of ONCAB as well. Possible reasons of these controversial opinions are that high-quality studies have not comprehensively examined relevant patient outcomes and have enrolled a limited range of patients. Some studies may have been too small to detect clinically important differences in patient outcomes between these two modalities. We present a review of the available scientific interpretation of the literature on OPCAB with regard to safety, hemodynamic changes, inflammation, myocardial preservation and oxidative stress. We also sought to determine from different reported retrospective and randomized control studies, the initial and the long-term benefits of this approach, despite the substantial learning curve associated with OPCAB.

Off-pump CABG with synchronized arterial flow ensuring system

PURPOSE

We developed a synchronized, arterial-flow, ensuring system to perform coronary anastomoses safely without any ischemia-related event.

DESCRIPTION

Arterial blood is removed from the femoral artery. The resulting blood passes a switching valve and is pumped out to a syringe pump. This pump controller provides pulsatile arterial blood flow synchronized with the diastolic phase on an electrocardiogram. The arterial blood is perfused to the coronary artery through a fine flexible cannula during anastomosis.

EVALUATION

From February 1999, 524 consecutive patients were operated on using the synchronized arterial flow ensuring system. Mean duration for each anastomosis was 7.6 +/- 3.3 minutes (range, 4 to 20 min). There were no intraoperative fatal arrhythmias, ventricular arrhythmias, or short-run or hemodynamic deterioration during anastomoses. No hospital death was observed, and postoperative myocardial infarction occurred in 2 patients (0.4%). Postoperative angiography showed a 98.1% patency rate.

CONCLUSIONS

The early clinical and angiographical results for off-pump CABG with the synchronized arterial flow ensuring system were excellent without mortality. We believe that off-pump CABG can be more safely performed using the synchronized arterial flow ensuring system based on our favorable results.

Aborted off-pump coronary artery bypass patients have much worse outcomes than on-pump or successful off-pump patients

BACKGROUND

Off-pump coronary artery bypass graft (CABG) surgery is purported to reduce perioperative mortality and morbidity compared with on-pump coronary bypass graft surgery. However, the outcomes of patients for whom an off-pump strategy must be changed to an on-pump procedure during surgery have not been extensively studied.

METHODS AND RESULTS

The Merged Cardiac Registry (Health Data Research, Inc) contains 70 514 isolated CABG performed from January 1998 to March 2004 in 40 facilities. Among them, 62 634 patients begun and completed on-pump bypass (CPB); 7880 patients begun off-pump, of which 7424 (94.2%) completed off-pump coronary artery bypass (OPCAB), whereas 456 (5.8%) were converted to on-pump (CONVERT). CONVERT patients were more severely ill. The observed mortality of CONVERT, CPB, and OPCAB was 9.9%, 3.0%, and 1.6%, respectively, and the observed-to-predicted ratio was 2.77, 1.20, and 0.74, respectively. CONVERT also had more morbidity than either OPCAB or CPB. Finally, a risk model was created to identify patients who might be at risk for conversion from off-pump to on-pump CABG.

CONCLUSIONS

Patients who are intended for an off-pump strategy and then require conversion to on-pump have significantly higher operative mortality and morbidity than either completed OPCAB or CPB patients. In addition, the operative mortality and morbidity are far in excess of that predicted preoperatively. Based on these results, strong consideration should be given for a planned strategy of CPB for those patients with preoperative hemodynamic instability requiring a salvage CABG operation, left ventricular hypertrophy, or previous CABG.

Portable coronary active perfusion system for off-pump coronary artery bypass grafting

PURPOSE

The present study was performed to develop a new perfusion system for off-pump coronary artery bypass grafting and to examine whether even a simple coronary perfusion system can maintain adequate blood flow delivery during anastomosis.

DESCRIPTION

The experiment was performed in two stages. In procedure 1, 3 pigs with left anterior descending artery occlusion were used to evaluate optimal perfusion flow rate and coronary artery internal pressure, and to evaluate the safety area of perfusion. In procedure 2, 6 pigs were used to validate the new portable coronary perfusion system.

EVALUATION

The optimal blood flow in the portable coronary active perfusion system was less than approximately 40 mL/min. The small, easy to use pump system (ie, the portable coronary active perfusion system) may prevent hemodynamic deterioration and ventricular arrhythmia during coronary occlusion, resulting in better maintenance of left ventricular function.

CONCLUSIONS

Even a simple pump system can achieve effective perfusion for safe anastomosis. Further studies are required to allow the clinical use of this system.

Perioperative Patency of Coronary Artery Bypass Grafting is Not Influenced by Off-Pump Technique

BACKGROUND

Some concerns have been raised about technical accuracy and quality of distal anastomoses in off-pump myocardial revascularization (OPCAB), which could affect graft patency.

METHODS

Transit-time flowmetric results and clinical, enzymatic, and echocardiographic findings from 201 consecutive isolated on-pump coronary artery bypass graft cases (cardiopulmonary bypass coronary artery bypass grafting; group A) were compared with 96 consecutive OPCAB (group B) cases performed at our institution between January 2003 and December 2004. Maximum, mean, minimum flow, and pulsatility index were compared, stratifying the two groups according to graft type and coronaries revascularized. Graft flow reserve was evaluated in patients undergoing preoperative intraaortic balloon pump during baseline conditions and at a 1 to 1 ratio of intraaortic balloon pump augmentation.

RESULTS

No differences were recorded between the two groups in hospital mortality, perioperative myocardial infarction, postoperative enzymatic leakage, echocardiographic recovery, or hospital stay (p = not significant). Off-pump coronary artery bypass and cardiopulmonary bypass coronary artery bypass grafting demonstrated similar intraoperative maximum (75.8 +/- 10.4 mL/min vs 82.3 +/- 15.8; p = 0.190), mean (50.1 +/- 13.3 vs 46.3 +/- 7.7; p = 0.420), minimum flow (12.7 +/- 5.3 vs 11.9 +/- 5.4; p = 0.811), and pulsatility index (2.9 +/- 0.2 vs 2.6 +/- 0.8; p = 0.360). After stratifying the population according to graft type, no differences were detected between the two groups in transit-time flowmetric results of left internal mammary artery, radial artery, and single and sequential saphenous vein grafts. A one to one ratio of intraaortic balloon pump augmentation did not result in any difference in graft flow reserve when left internal mammary artery (p = 0.699), radial artery (p = 0.066), and saphenous vein graft anastomoses (p = 0.772) were considered.

CONCLUSIONS

Off-pump coronary artery bypass grafting and cardiopulmonary bypass coronary artery bypass grafting demonstrated similar clinical, biochemical, and transit-time flowmetric results, as well as comparable graft flow reserve. These data exclude a lower anastomotic quality in off-pump coronary artery bypass grafting.

Acute ischemic cardiac dysfunction is attenuated via gene transfer of a peptide inhibitor of the beta-adrenergic receptor kinase (betaARK1)

Acute myocardial ischemia is a critical adverse effect potentially occurring during cardiac procedures. A peptide inhibitor of the beta-adrenergic receptor kinase (betaARK1), betaARKct, has been successful in rescuing chronic myocardial ischemia. The present study focused on the effects of adenoviral-mediated betaARKct (Adv-betaARKct) delivery on left ventricle (LV) dysfunction induced by acute coronary occlusion. Rabbits received intracoronary delivery of phosphate-buffered saline (PBS) (n=9) or 5x10(11) viral particles of betaARKct (n=8). A loose prolene 5-0 Potz-loop suture was placed around the circumflex coronary artery (LCx) with both ends buried under the skin. Four days later, the suture was retrieved and pulled to occlude the LCx. Ischemia was confirmed by immediate ECG changes. LV function was continuously recorded for 45 min. Contractility (LVdP/dtmax), relaxation (LVdP/dtmin) and end diastolic pressure (EDP) were less impaired in the betaARKct group as compared to PBS (P<0.05, two-way ANOVA). betaAR density was higher in the ischemic area of the LV in the betaARKct group (betaARKct: 71.9+/-4.6 fmol/mg protein, PBS: 54.5+/-4.0 fmol/mg protein, P<0.05). Adenylyl cyclase activity was also improved basally and in response to betaAR stimulation. betaARK1 activation was less in the betaARKct group (P<0.05). Therefore, inhibition of myocardial betaARK1 may represent a new strategy to prevent LV dysfunction induced by acute coronary ischemia.

Off-pump coronary artery bypass graft surgery: where should we stand?

Coronary artery bypass grafting (CABG) performed with cardiopulmonary bypass has become a well-established treatment modality for patients with coronary artery disease. However, there is increasing evidence that cardiopulmonary bypass may be responsible for some of the morbidity associated with CABG surgery. Thus, it has been proposed that CABG surgery would be safer if cardiopulmonary bypass could be avoided. The development of cardiac stabilization devices has allowed for the creation of safe and reproducible coronary anastomoses on the beating heart. Several large, non-randomized, retrospective case series have demonstrated that CABG surgery can be performed safely without cardiopulmonary bypass (off-pump) and have in fact suggested benefits when compared with conventional CABG. However, the randomized controlled studies published to date have, as a whole, been unable to conclusively demonstrate the advantages of off-pump surgery. Taken together, the evidence to date suggests that a large-scale, prospective, randomized trial may be required to resolve the dilemma.

Four years' experience with a miniaturized extracorporeal circulation system and its influence on clinical outcome

It has been suggested that the morbidity associated with cardiopulmonary bypass can be attributed in part to the blood-material and blood-air interactions in the extracorporeal circulation (ECC). A recently introduced minimized ECC-system (MECC System) should be able to reduce these negative effects associated with ECC. A retrospective analysis was performed comprising 485 patients who were operated on for elective coronary artery bypass grafting (CABG) using the MECC System with intermittent antegrade warm blood cardioplegia (group 1) from January 2000 to February 2004. A control group consisted of 485 patients (group 2) undergoing elective CABG in the same period using a conventional ECC and cold crystalloid cardioplegia. There were no significant differences between the two groups in terms of the duration of intubation following surgery, the length of intensive care unit-stay and the total hospital stay. Although the 30-day mortality was similar between the two groups, the incidence of postoperative complications and the perioperative use of blood products were significantly higher in the control group compared to the MECC group. The MECC System may serve as an alternative and less invasive approach to conventional ECC.

Hemodynamic Changes During Posterior Vessel Off-Pump Coronary Artery Bypass: Comparison Between Deep Pericardial Sutures and Vacuum-Assisted Apical Suction Device

BACKGROUND

Displacement of the heart to expose posterior vessels during off-pump coronary artery bypass may cause hemodynamic derangement. The aims of this study were (1) to elucidate the hemodynamic changes during off-pump coronary artery bypass for the obtuse marginal branch (OM) of the left circumflex artery; and (2) to compare the hemodynamic changes caused by a deep pericardial suture technique with those caused by a vacuum-assisted apical suction device for displacement of the heart.

METHODS

Hemodynamic changes during posterior vessel off-pump coronary artery bypass were studied in a prospective randomized manner. A deep pericardial suture technique (group 1, n = 10) or a vacuum-assisted apical suction device (group 2, n = 10) was used to facilitate the exposure of the OM. Hemodynamic variables such as cardiac index, stroke volume index (SVI), mean arterial pressure, mean pulmonary artery pressure, central venous pressure, pulmonary capillary wedge pressure, heart rate, systemic vascular resistance, pulmonary vascular resistance, left ventricular stroke work index, and right ventricular stroke work index were monitored during off-pump coronary artery bypass. Hemodynamic data were obtained before revascularization of the left anterior descending coronary artery at a baseline (T0), 3 minutes after heart displacement for revascularization of OM (T1), 3 minutes after the beginning of OM grafting (T2), and 3 minutes after the completion of OM grafting and heart repositioning (T3).

RESULTS

There were no significant differences in the baseline hemodynamic variables (T0) between the two groups. In group 1, SVI, cardiac index, left ventricular stroke work index, and right ventricular stroke work index decreased significantly, and central venous pressure and pulmonary capillary wedge pressure increased significantly, during displacement of the heart (T1, p < 0.05). In group 2, SVI decreased significantly, and central venous pressure, pulmonary capillary wedge pressure, and mean pulmonary artery pressure increased significantly during displacement of the heart (T1, p < 0.05). The percent changes of cardiac index, SVI, and right ventricular stroke work index during OM grafting (T2) in comparison with baseline values (T0) were significantly larger in group 1 than in group 2 (cardiac index, 73% +/- 12% versus 90% +/- 11%; SVI, 69% +/- 12% versus 86% +/- 8%; right ventricular stroke work index, 30% +/- 17% versus 71% +/- 25%, in groups 1 versus 2, respectively; p < 0.05).

CONCLUSIONS

Displacement of the heart using either a deep pericardial suture technique or a vacuum-assisted apical suction device caused a significant decrease in SVI. The hemodynamic changes during OM grafting were smaller when using a vacuum-assisted apical suction device.

Usefulness of preoperative intraaortic balloon pump therapy during off-pump coronary artery bypass grafting in high-risk patients

BACKGROUND

In off-pump coronary artery bypass grafting (OPCABG) surgery, the most critical complication is hemodynamic deterioration, which can occur during displacement of the heart to expose the target vessels. Preoperative intraaortic balloon pump (IABP) therapy improves cardiac performance and facilitates access to the target coronary artery while maintaining hemodynamic stability, especially in high-risk patients.

METHODS

One hundred thirty-three consecutive patients who underwent OPCABG through sternotomy between April 2000 and July 2003 were studied. We compared the clinical results of 32 patients who underwent preoperative IABP placement (group 1) with those of 101 patients who did not have IABP placement (group 2). Of the 32 patients satisfying the insertion criteria, 15 had critical left main artery disease, 20 had unstable angina, 5 had acute myocardial infarction, and 5 had left ventricular dysfunction.

RESULTS

There were no significant differences in the average number of distal anastomoses performed between group 1 and group 2 (3.1 +/- 0.8 versus 3.3 +/- 0.9, p = not significant). The complete revascularization rate was 95% in both group. There was no conversion to on-pump surgery in either group. There was no operative death in group 1 and only 1 death in group 2. In group 1, the number of patients who required prolonged ventilatory support (longer than 48 hours) was higher (3 versus 1, p = 0.036), and there was a higher incidence of low cardiac output syndrome (1 versus 0, p = 0.074). There were no IABP-related complications in group 1.

CONCLUSIONS

Preoperative IABP therapy for high-risk coronary patients is very effective in preventing hemodynamic instability and providing surgical results comparable with those in moderate- to lower-risk patients.

Off-pump coronary artery bypass surgery: physiology and anaesthetic management †

Increasing interest is being shown in beating heart (off-pump) coronary artery surgery (OPCAB) because, compared with operations performed with cardiopulmonary bypass, OPCAB surgery may be associated with decreased postoperative morbidity and reduced total costs. Its appears to produce better results than conventional surgery in high-risk patient populations, elderly patients, and those with compromised cardiac function or coagulation disorders. Recent improvements in the technique have resulted in the possibility of multiple-vessel grafting in all coronary territories, with a graft patency comparable with conventional surgery. During beating-heart surgery, anaesthetists face two problems: first, the maintenance of haemodynamic stability during heart enucleation necessary for accessing each coronary artery; and second, the management of intraoperative myocardial ischaemia when coronary flow must be interrupted during grafting. The anaesthetic technique is less important than adequate management of these two major constraints. However, experimental and recent clinical data suggest that volatile anaesthetics have a marked cardioprotective effect against ischaemia, and might be specifically indicated. OPCAB surgery requires team work between anaesthetists and surgeons, who must be aware of each other's constraints. Some surgical aspects of the operation are reviewed along with physiological and anaesthetic data.

Our experiences for off-pump coronary artery bypass grafting to the circumflex system

BACKGROUND

Complete revascularization has been difficult in off-pump coronary artery bypass grafting (OPCAB). Hemodynamic deterioration often prevents access to the circumflex territory. This study presents instrumentation for accessing the circumflex territory, and our clinical experience.

METHODS

From August 1999 through December 2002, 140 patients underwent OPCAB via sternotomy in our institution. The 114 requiring reconstruction of the circumflex artery are the subjects of this study. There were no exclusion criteria. A series of techniques and instruments were developed to provide access to the circumflex area while hemodynamic stability was preserved, including the left pericardial traction technique, compression of the right pericardium, a right sternal retractor, and a type of shunt tube.

RESULTS

Patients received an average of 3.2 grafts (range, 2 to 6). Complete revascularization was achieved in 95% of the cases. Complications included respiratory insufficiency (0.8%), renal dysfunction (7%), and sternal wound infection (0.8%). Blood transfusions were required in 10 patients (8%). No patient suffered perioperative myocardial infarction or stroke. No operation was converted to cardiopulmonary bypass. There was no operative death. Predischarge angiography demonstrated a 99% patency rate.

CONCLUSIONS

With our techniques and instruments, off-pump coronary revascularizaion of the circumflex area may be performed safely to achieve complete revascularization. Early clinical results are excellent, but long-term longitudinal follow-up is required to assess the future effectiveness of OPCAB procedure with our techniques.

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.

Perfusion-assisted direct coronary artery bypass provides early reperfusion of ischemic myocardium and facilitates complete revascularization

BACKGROUND

Perfusion-assisted direct coronary artery bypass (PADCAB) was developed to initiate early reperfusion of grafted coronary artery segments during off-pump operations to resolve episodes of myocardial ischemia and avoid its sequelae. This case series outlines intraoperative findings and clinical outcomes of our first year clinical experience with PADCAB.

METHODS

From November 1999 to November 2000, 169 PADCAB and 358 off-pump coronary artery bypass procedures were performed at the Emory University Hospitals. The decision to use PADCAB was predicated on surgeon preference. Perfusion pressure and flow, amount of intracoronary nitroglycerin, and total perfusion time and volume were recorded at the time of operation.

RESULTS

One off-pump coronary artery bypass patient required emergent conversion to cardiopulmonary bypass. Two PADCAB patients had ischemic ventricular arrhythmias during target vessel occlusion that resolved once active perfusion had begun. Perfusion pressure in PADCAB grafts was on average 44% higher than mean arterial pressure (p < 0.001). Nitroglycerin, infused locally by PADCAB, was used in 67 patients to resolve ischemic episodes and increase initial coronary flows. The mean number of diseased coronary territories and grafts placed was 2.8 +/- 0.5 and 3.4 +/- 0.7, respectively, in the PADCAB group, and 2.3 +/- 0.8 and 2.7 +/- 1.0, respectively, in the off-pump coronary artery bypass group (p < 0.001 for both comparisons). More PADCAB patients received lateral wall grafts than off-pump coronary artery bypass patients (83.4% vs 59.4%; p < 0.001). Hospital death and postoperative myocardial infarction were not different between groups.

CONCLUSIONS

PADCAB can provide suprasystemic perfusion pressures and a means to add vasoactive drugs to target coronary vessels. PADCAB provides early reperfusion of ischemic myocardium and facilitates complete revascularization of severe multivessel coronary artery disease.