Anesthetic management of robotically assisted totally endoscopic coronary artery bypass surgery (TECAB).

Over the last decade, TECAB has matured into a reproducible technique associated with low incidence of both mortality and morbidity, as well as superior quality of life, when compared with open CABG surgery. However, TECAB also is associated with important and specific challenges for the anesthesiology team, particularly with regard to the physiologic stresses of OLV, placement of special catheters, and induced capnothorax. As the technology supporting robotic surgery evolves and familiarity with, and confidence in, TECAB increases, the authors anticipate increasingly widespread use of these procedures in an increasingly fragile and problematic patient population who will require the support of a skilled and vigilant anesthesiology team.

Hybrid coronary revascularization: which patients? When? How?

PURPOSE OF REVIEW: The aim of this review is to report on current indications and patient selection for hybrid coronary revascularization and to outline current techniques for a hybrid approach. RECENT FINDINGS: Hybrid coronary intervention is a revascularization strategy that combines surgical and catheter-based procedures for treatment of multivessel coronary artery disease. Most published studies report on application of this concept in patients with complex lesions of the left anterior descending artery and nonleft anterior descending lesions suited for percutaneous coronary intervention. Currently, the spectrum of surgical procedures in hybrid coronary revascularization ranges from left internal mammary artery bypass grafting via sternotomy and minithoracotomy to completely endoscopic robotic double vessel coronary artery bypass grafting. Percutaneous coronary intervention in hybrid procedures is performed as single or multiple coronary angioplasty with stenting using either bare metal or drug-eluting stents. Staged and simultaneous approaches can be applied. The latter are increasingly performed in the hybrid operating room. SUMMARY: Hybrid coronary intervention is an emerging interdisciplinary approach in the treatment of coronary artery disease and a potential viable alternative to open coronary bypass surgery or multivessel stenting.

Hybrid coronary revascularization: an overview of options for anticoagulation and platelet inhibition.

BACKGROUND: Hybrid coronary revascularization, in which coronary bypass grafting is combined with percutaneous coronary intervention, is a promising strategy for optimizing outcomes in the treatment of coronary artery disease. Balancing the risk of surgical bleeding with the risk of percutaneous coronary intervention-related thrombosis is a major challenge inherent in carrying out a successful procedure and requires careful selection of antiplatelet and anticoagulant agents. METHODS: Advantages and disadvantages of antiplatelet and anticoagulant agents in use today for hybrid coronary revascularization are reviewed. RESULTS: Currently available anticoagulants and platelet inhibitors have been used to provide safe and effective protection from thrombosis while limiting surgical bleeding in hybrid coronary revascularization, but there is no agreement on an optimal strategy, and each patient presents a unique pharmacologic and logistic puzzle. CONCLUSION: Knowledge of the salient features of the available medications will allow the cardiologist and surgeon to design the optimal strategy for each patient.

Robotic totally endoscopic triple coronary artery bypass grafting on the arrested heart: report of the first successful clinical case.

Robotic technology enables "port only" totally endoscopic coronary artery bypass grafting (TECAB). During early procedure development only single bypass grafts were feasible. Because current referral practice for coronary bypass surgery mostly includes multivessel disease, performance of multiple endoscopic bypass grafts is desirable. We report a case in which a patient received a right internal mammary artery bypass graft to the left anterior descending artery and a left internal mammary artery jump graft to 2 obtuse marginal branches. The procedure was performed through 5 ports on the arrested heart using the daVinci S robotic surgical system. This is the first reported triple bypass grafting procedure using an arrested heart approach.

Is an intraaortic balloon pump a contraindication to robotic totally endoscopic coronary artery bypass?

BACKGROUND: The success of robotic totally endoscopic coronary artery bypass (TECAB) in recent years has led to the expansion of the procedure to patients with more severe disease. Outcomes with these patients have not yet been well characterized, and no reports on TECAB performed in patients with a preoperatively placed intraaortic balloon pump (IABP) are available. We present our initial experience with this patient population. PATIENTS AND METHODS: We evaluated 5 patients with unstable angina or impaired left ventricular function requiring a preoperatively placed IABP who underwent TECAB using the daVinci telemanipulation system. Procedures were performed either on the beating heart using an endostabilizer (n = 2) or on the arrested heart using remote access perfusion and aortic balloon endoocclusion (n = 3). The median patient age was 67 years (range, 41-73 years), with a median preoperative ejection fraction of 43% (range, 26%-58%) and median EuroSCORE of 5 (range, 3-8). RESULTS: There were no major intraoperative technical issues. The median length of stay in the hospital and intensive care unit was 8 days (range, 5-13 days) and 66 hours (range, 41-142 hours), respectively. There were no intraoperative or 30-day mortalities. CONCLUSIONS: This early experience suggests that TECAB is feasible in patients with a preoperatively placed IABP. Both the beating heart and arrested heart versions can be used in this patient population, further broadening the spectrum of applicability of this procedure.

Time Course of LDL Cholesterol Exposure and Cardiovascular Disease Event Risk.

BACKGROUND: Incident cardiovascular disease (CVD) increases with increasing low-density lipoprotein cholesterol (LDL-C) concentration and exposure duration. Area under the LDL-C versus age curve is a possible risk parameter. Data-based demonstration of this metric is unavailable and whether the time course of area accumulation modulates risk is unknown. OBJECTIVES: Using CARDIA (Coronary Artery Risk Development in Young Adults) study data, we assessed the relationship of area under LDL-C versus age curve to incident CVD event risk and modulation of risk by time course of area accumulation-whether risk increase for the same area increment is different at different ages. METHODS: This prospective study included 4,958 asymptomatic adults age 18 to 30 years enrolled from 1985 to 1986. The outcome was a composite of nonfatal coronary heart disease, stroke, transient ischemic attack, heart failure hospitalization, cardiac revascularization, peripheral arterial disease intervention, or cardiovascular death. RESULTS: During a median 16-year follow-up after age 40 years, 275 participants had an incident CVD event. After adjustment for sex, race, and traditional risk factors, both area under LDL-C versus age curve and time course of area accumulation (slope of LDL-C curve) were significantly associated with CVD event risk (hazard ratio: 1.053; p < 0.0001 per 100 mg/dl × years; hazard ratio: 0.797 per mg/dl/year; p = 0.045, respectively). CONCLUSIONS: Incident CVD event risk depends on cumulative prior exposure to LDL-C and, independently, time course of area accumulation. The same area accumulated at a younger age, compared with older age, resulted in a greater risk increase, emphasizing the importance of optimal LDL-C control starting early in life.

On-pump beating-heart with axillary artery perfusion: a solution for robotic totally endoscopic coronary artery bypass grafting?

Robotic totally endoscopic coronary artery bypass grafting (TECAB) can be performed on the arrested heart or on the beating heart without heart-lung machine support. In high-risk patients or in patients where technical difficulties are expected with a complete off-pump approach, a beating heart concept with heart-lung machine support can be an important option. Femoral arterial cannulation is associated with additional risk of retrograde cerebral embolization, and axillary cannulation is an accepted method in aortic surgery. We describe a case where an axillary artery cannulation method was used for the first time in TECAB performed with the da Vinci telemanipulation system.

Poor left ventricular function is not a contraindication for robotic totally endoscopic coronary artery bypass grafting.

Robotic technology has enabled performance of totally endoscopic coronary artery bypass grafting (TECABG). Published series on TECABG were primarily performed in low-risk patients, and little is known about the outcome after totally endoscopic coronary surgery in patients with severely impaired left ventricular function. We report successful endoscopic placement of a left internal mammary artery bypass graft to the left anterior descending artery using the daVinci robotic system in a patient with a severely reduced left ventricular ejection fraction.

Totally endoscopic coronary artery bypass grafting is feasible in morbidly obese patients.

Development of robotic technology has enabled totally endoscopic coronary artery bypass grafting (TECAB) procedures. With complete preservation of sternal and thoracic stability, this operation would be an interesting option for obese patients, who are known to be at higher risk for deep sternal wound infection. We describe a case of successful totally endoscopic left internal mammary artery to left anterior descending artery bypass grafting using the da Vinci telemanipulation system in a patient who was morbidly obese. The patient underwent a so called staged hybrid coronary intervention with percutaneous angioplasty and placement of a stent to the right coronary artery.

Comparison of economic and patient outcomes with minimally invasive versus traditional off-pump coronary artery bypass grafting techniques.

BACKGROUND: Minimally invasive coronary artery bypass grafting (miniCABG) decreases in-hospital morbidity versus traditional sternotomy CABG. We performed a prospective cohort study (NCT00481806) to assess the impact of miniCABG on costs and metrics that influence quality of life after hospital discharge. METHODS: One hundred consecutive miniCABG cases performed using internal mammary artery (IMA) grafting +/- coronary stenting were compared with a matched group of 100 sternotomy CABG patients using IMA and saphenous veins, both treating equivalent number of target coronaries (2.7 vs. 2.9), off-pump. We compared perioperative costs, time to return to work/normal activity, and risk of major adverse cardiac/cerebrovascular events (MACCE) at 1 year: myocardial infarction (elevated troponin or EKG changes), target vessel occlusion (CT angiography at 1 year), stroke, or death. RESULTS: For miniCABG, robotic instruments and stents increased intraoperative costs; postoperative costs were decreased from significantly less intubation time (4.80 +/- 6.35 vs. 12.24 +/- 6.24 hours), hospital stay (3.77 +/- 1.51 vs. 6.38 +/- 2.23 days), and transfusion (0.16 +/- 0.37 vs. 1.37 +/- 1.35 U) leading to no significant differences in total costs. Undergoing miniCABG independently predicted earlier return to work after adjusting for confounders (t = -2.15; P = 0.04), whereas sternotomy CABG increased MACCE (HR, 3.9; 95% CI, 1.4-7.6), largely from lower target-vessel patency. CONCLUSIONS: MiniCABG shortens patient recovery time, minimizes MACCE risk at 1 year, and showed superior quality and outcome metrics versus standard-of-care CABG. These findings occurred without increasing costs and with superior target vessel graft patency.

Simultaneous "hybrid" percutaneous coronary intervention and minimally invasive surgical bypass grafting: feasibility, safety, and clinical outcomes.

Surgical and percutaneous coronary artery intervention revascularization are traditionally considered isolated options. A simultaneous hybrid approach may allow an opportunity to match the best strategy for a particular anatomic lesion. Concerns regarding safety and feasibility of such an approach exist. We examined the safety, feasibility, and early outcomes of a simultaneous hybrid revascularization strategy (minimally invasive direct coronary bypass grafting of the left anterior descending [LAD] artery and drug-eluting stent [DES] to non-LAD lesions) in 13 patients with multivessel coronary artery disease that underwent left internal mammary artery to LAD minimally invasive direct coronary bypass performed through a lateral thoracotomy, followed by stenting of non-LAD lesions, in a fluoroscopy-equipped operating room. Assessment of coagulation parameters was also undertaken. Inhospital and postdischarge outcomes of these patients were compared to a group of 26 propensity score matched parallel controls that underwent standard off-pump coronary artery bypass. Baseline characteristics were similar in both groups. All hybrid patients were successfully treated with DES and no inhospital mortality occurred in either group. Hybrid patients had a shorter length of stay (3.6 +/- 1.5 vs 6.3 +/- 2.3 days, P < .0001) and intubation times (0.5 +/- 1.3 vs 11.7 +/- 9.6 hours, P < .02). Despite aggressive anticoagulation and confirmed platelet inhibition, hybrid patients had less blood loss (581 +/- 402 vs 1242 +/- 941 mL, P < .05) and decreased transfusions (0.33 +/- 0.49 vs 1.47 +/- 1.53 U, P < .01). Six-month angiographic vessel patency and major adverse cardiac events were similar in the hybrid and off-pump coronary artery bypass groups. A simultaneous hybrid approach consisting of minimally invasive coronary artery bypass grafting with left internal mammary artery to LAD combined with revascularization of the remaining coronary targets using percutaneous coronary artery intervention with DES is a feasible option accomplished with acceptable clinical outcomes without increased bleeding risk.

Surgery for severe mitral regurgitation and left ventricular failure: what do we really know?

In ischemic and nonischemic cardiomyopathy, functional mitral regurgitation (MR) results from geometric abnormalities of the ventricle, which result in dysfunction of a morphologically normal mitral valve. Enlargement of the left ventricle causes geometric MR through annular dilation, increase in the interpapillary muscle distance, amplified leaflet tethering (elongation and stretch on the chordae tendinae), and decreased closing forces because of muscle weakness and asynchrony of papillary muscle contractile timing. The final common pathway of MR is a failure of coaptation of the morphologically normal leaflets and resultant central MR. These abnormalities can be favorably influenced by antiremodeling pharmacologic therapy and in selected cases by cardiac resynchronization therapy. Surgical repair of functional geometric MR with an undersized complete rigid annuloplasty ring can abolish MR and is associated with improved functional status and left ventricular remodeling. It is unclear if surgery is associated with improved survival in this setting. There is a pressing need for well-conducted prospective randomized clinical trials to quantify the benefits of surgical repair of functional geometric MR.

Heart failure and "inoperable" aortic stenosis: staged balloon aortic valvuloplasty and aortic valve bypass.

The prognosis for patients with symptomatic aortic stenosis is poor but is improved significantly by surgical aortic valve replacement. Unfortunately, many patients are refused surgery because of age, comorbidities, and hemodynamic instability. This report describes the successful use of balloon aortic valvuloplasty as a bridge to aortic valve bypass surgery (apicoaortic conduit) in an elderly patient with class IV congestive heart failure and severe left ventricular systolic dysfunction as a consequence of aortic stenosis who was not a candidate for traditional surgical valve replacement.

Advanced hybrid closed chest revascularization: an innovative strategy for the treatment of multivessel coronary artery disease†.

OBJECTIVES: Conventional hybrid revascularization (CHR) combines minimally invasive placement of an internal mammary artery graft to the anterior wall and percutaneous coronary intervention (PCI) of non-anterior wall targets. In this study we assess perioperative and midterm outcomes of advanced hybrid revascularization (AHR) defined as the combination of single or multivessel (MV) totally endoscopic coronary artery bypass grafting (TECAB) with single or multivessel PCI. METHODS: In total, 90 AHR patients [median age 62 years (35-86)] were compared with 90 CHR patients [median age 60 years (35-85)] in terms of perioperative and mid-term outcomes. The outcomes of the three different AHR options (MV-TECAB + PCI, MV-PCI + TECAB, MV-TECAB + MV-PCI) as well as the sequence of the interventions were further compared. Risk factors for major adverse cardiac and cerebral events (MACCEs) related to the hybrid revascularization strategy were calculated. RESULTS: No perioperative deaths occurred either in the AHR group or in the CHR group, rates of myocardial infarction (3.3% vs 3.3%, P = 0.196) were similar between CHR and AHR. Operative times were longer in the AHR group [337 (137-794) min vs 272 (148-550) min, P = 0.002] and conversion rates slightly higher (P = 0.060); however, intensive care unit length of stay (P = 0.162) and hospital length of stay (P = 0.238) were similar. There was no difference in the follow-up survival (P = 0.091), freedom from angina (P = 0.844), PCI target vessel revascularization (P = 0.563), TECAB target vessel revascularization (P = 0.135) and MACCEs (P = 0.601) between CHR and AHR at follow-up. No differences were detected between the three variations of AHR in perioperative outcome, mid-term survival, freedom from MACCEs and reintervention. Neither the number nor type of TECAB/PCI targets, nor the sequence of interventions were significant predictors for MACCEs at follow-up. CONCLUSIONS: AHR yields comparable results with CHR and can be taken into consideration as a sternum-sparing technique for the treatment of MV-coronary artery disease in selected patients.

Predictors and consequences of postoperative atrial fibrillation following robotic totally endoscopic coronary bypass surgery.

OBJECTIVES: Postoperative atrial fibrillation (AFib) is common in patients undergoing coronary artery bypass grafting. Little information is available concerning AFib following minimally invasive cardiac surgery. The aim of our study was to assess the incidence of AFib after totally endoscopic coronary artery bypass (TECAB) grafting and to investigate the factors influencing its occurrence. METHODS: Between 2001 and 2010, we performed TECAB in 384 patients, 73% male, aged 60 (37-90) years. Single-vessel bypasses were performed in 280 patients, and 104 received multivessel coronary revascularization. Procedures were performed on the beating heart in 80 cases, and 164 patients underwent a hybrid intervention. RESULTS: A total of 59 patients (15.4%) developed AFib after TECAB. Univariate analysis showed hypertension (P=0.005), increased age (P=0.007), body weight (P=0.006), body mass index (P=0.005), EuroSCORE (P=0.035) and total TECAB operation time (P=0.01) to be significantly associated with AFib. We also found an increased incidence of AFib in patients undergoing hybrid interventions (P=0.036) and beating heart TECAB (P=0.003). Age (P<0.001) and higher body weight (P=0.003) were the only predictors found to be significant in multivariate analysis. Hospital mortality was 1.7% (1 of 59) in the group of patients with AFib and 0.6% (2 of 325) in the group that showed no AFib after operation (P=n.s.). Hospital stay was 7 (4-54) days in patients with AFib and 6 (2-33) days in those without AFib (P=n.s.). There was no significant 5-year survival difference in patients with and without postoperative AFib (94 vs 94%, P=n.s.). CONCLUSIONS: We conclude that the incidence of postoperative AFib in TECAB is relatively low. Age and body weight are the most important predictors of postoperative AFib following TECAB. Short-term clinical outcome and intermediate-term survival are similar in patients with and without postoperative AFib.

Five hundred cases of robotic totally endoscopic coronary artery bypass grafting: predictors of success and safety.

BACKGROUND: Robotic technology has enabled totally endoscopic coronary artery bypass (TECAB) grafting. Little information is available on factors associated with successful and safe performance of TECAB. We report a 10-year multicenter experience with 500 cases, elucidating on predictors of success and safety in TECAB procedures. METHODS: Between 2001 and 2011, 500 patients (364 [73%] men; 136 [27%] women; median age [minimum-maximum] 60 years [31-90 years], median EuroSCORE 2 [0-13]), underwent TECAB. Single, double, triple, and quadruple TECAB was performed in 334, 150, 15, and 1 patient, respectively. Univariate analysis and binary regression models were used to identify predictors of success and safety. Success was defined as freedom from any adverse event and conversion procedure, safety was defined as freedom from major adverse cardiac and cerebral events, major vascular injury, and long-term ventilation. RESULTS: Success and safety rates were 80% (400 cases) and 95% (474 cases), respectively. Intraoperative conversions to larger thoracic incisions were required in 49 (10%) patients. The median operative time was 305 minutes (112-1,050 minutes), and the mean lengths of stay in the intensive unit (ICU) and in hospital were 23 hours (11-1,048 hours) and 6 days (2-4 days), respectively. Independent predictors of success were single-vessel TECAB (p = 0.004), arrested-heart (AH)-TECAB (p = 0.027), non-learning curve case (p = 0.049), and transthoracic assistance (p = 0.035). The only independent predictor of safety was EuroSCORE (p = 0.002). CONCLUSIONS: Single-vessel and multivessel TECAB procedures can be safely performed with good reproducible results. Predictors of success include procedure simplicity and non-learning curve cases, whereas predictors of safety are mainly associated with patient selection.

Robotically assisted hybrid coronary revascularization: does sequence of intervention matter?

OBJECTIVE: Hybrid coronary revascularization (HCR) is a treatment strategy for the revascularization of multivessel coronary disease that combines the advantages of both minimally invasive surgical techniques and percutaneous coronary intervention (PCI). The optimal sequence by which revascularization should be accomplished has not been determined. We investigated clinical outcomes in a series of patients planned for HCR via robotically assisted totally endoscopic coronary artery bypass (TECAB) and standard PCI based on revascularization sequence. METHODS: A total of 238 patients planned for HCR between 2001 and 2011 were divided into three groups based on treatment sequence: (a) TECAB before PCI, (b) PCI before TECAB, and (c) same-session procedure. Multiple procedural and clinical end points before discharge and up to 2 years after the procedure were compared between the three groups in an intention-to-treat analysis. Demographic features were reviewed to determine baseline differences between each group. RESULTS: Of the 238 patients, 175 (73.5%) underwent TECAB before PCI, 38 patients (16.0%) underwent PCI before TECAB, and 25 (10.5%) underwent a simultaneous revascularization procedure. At baseline, the patients undergoing TECAB before PCI were significantly older. There was a significantly higher incidence of previous myocardial infarction in the PCI-first group (P < 0.001). There was a significant difference in intensive care unit (ICU) length of stay (LOS), with shorter ICU stays in the simultaneous revascularization group (P = 0.031) and shorter hospital LOS in the PCI before TECAB group (P = 0.021). CONCLUSIONS: In conclusion, revascularization sequence did not dramatically impact clinical outcomes in our observational study. The patients undergoing PCI-first and same-session interventions had shorter hospital and ICU LOS compared with the patients undergoing surgery first. Our findings suggest that no revascularization approach is arbitrarily superior and that revascularization sequence should be individualized on the basis of patient presentation and anatomical considerations.

Hybrid coronary revascularization using robotic totally endoscopic surgery: perioperative outcomes and 5-year results.

BACKGROUND: Hybrid coronary revascularization combines minimally invasive coronary artery bypass grafting and catheter-based interventions. This treatment option represents a viable alternative to both open multivessel coronary bypass surgery through sternotomy and multivessel percutaneous coronary intervention. The surgical component of hybrid coronary intervention can be offered in a completely endoscopic fashion using robotic technology. We report on one of the largest series to date. METHODS: From 2001 to 2011, 226 patients (age, 61 years [range, 31 to 90 years]; 77.0% male; EuroSCORE, 2 [range, 0 to 13]) underwent hybrid coronary interventions on an intention-to-treat basis. Robotically assisted procedures were performed using the daVinci, daVinci S, and daVinci Si surgical telemanipulation systems (Intuitive Surgical, Inc, Sunnyvale, CA) and included 147 single, 72 double, and 7 triple endoscopic coronary artery bypass grafting procedures. Surgery was carried out first in 160 cases (70.8%), percutaneous coronary intervention was carried out first in 38 cases (16.8%), and 28 patients underwent simultaneous operations in a hybrid operating room (12.4%). Drug-eluting stents were used in 70.0% of the patients. RESULTS: Hospital mortality was 3 of 226 patients (1.3%), and hospital stay averaged 6 days (range, 3 to 54 days). Patients walked outside 7 days (range, 3 to 97 days) postoperatively and performed general household work 14 days (range, 7 to 180 days) postoperatively. Full activity was resumed at 42 days (range, 7 to 720 days). Five-year survival was 92.9%, and 5-year freedom from major adverse cardiac and cerebral events was 75.2%. At 5 years, 2.7% of bypass grafts and 14.2% of percutaneous coronary intervention targets needed reintervention. CONCLUSIONS: Robotically assisted hybrid coronary intervention enables surgical treatment of multivessel coronary artery disease with minimal trauma. Perioperative results and intermediate-term outcomes meet the standards of open coronary artery bypass grafting. Recovery time is short, and reintervention rates are acceptable.

Predictors, causes, and consequences of conversions in robotically enhanced totally endoscopic coronary artery bypass graft surgery.

BACKGROUND: Totally endoscopic coronary artery bypass graft surgery (TECAB), using the da Vinci telemanipulator, has become a reproducible operation at dedicated centers. As in every endoscopic operation, conversion is an important and probably inevitable issue. METHODS: We performed robotic TECAB in 326 patients (age, 60 years; range, 31 to 90 years); 242 were single-vessel and 84 were multivessel TECAB. RESULTS: Forty-six of 326 patients (14%) were converted to a larger incision (minithoracotomy, n = 5; sternotomy, n = 41). Left internal mammary artery injury (n = 7), epicardial injury (n = 4), balloon endoocclusion problems (n = 7), and anastomotic problems (n = 18) were common reasons for conversions. Conversion rate was significantly less for single-vessel versus multivessel TECABs (10% versus 25%; p = 0.001). Non-learning-curve case (7% versus 21%; p < 0.001) and transthoracic assistance (11% versus 22%; p = 0.018) were associated with lower conversion rates. In multivariate analysis, learning-curve case was the only independent predictor of conversion (p = 0.005). Conversion translated into increased packed red blood cell transfusion in the operating room (3 versus 0 units; p < 0.001), longer ventilation time (14 versus 8 hours; p < 0.001), and intensive care unit stay (45 versus 20 hours; p = 0.001). Hospital mortality was 0.6% in this series, with 1 patient in the conversion group (2.2%) and 1 patient in the nonconverted group (0.4%; not significant). Five-year survival was 98% in nonconverted patients and 88% in converted patients (p = 0.018). There was no difference in freedom from angina or freedom from major adverse cardiac and cerebral events. CONCLUSIONS: Conversion in TECAB is primarily learning curve-dependent and associated with increased morbidity, but does not significantly affect hospital mortality. Both nonconverted and converted patients show good long-term survival, which is comparable to patients undergoing open sternotomy coronary artery bypass grafting. Long-term freedom from angina or freedom from major adverse cardiac and cerebral events is not influenced by conversion.