Anterolateral territory coronary artery bypass grafting strategies: a non-inferiority randomized clinical trial: the AMI-PONT trial.

OBJECTIVES: The main objective was to assess whether a composite coronary artery bypass grafting strategy including a saphenous vein graft bridge to distribute left internal mammary artery outflow provides non-inferior patency rates compared to conventional grafting surgery with separated left internal mammary artery to left anterior descending coronary graft and aorto-coronary saphenous vein grafts to other anterolateral targets. METHODS: All patients underwent isolated grafting surgery with cardiopulmonary bypass and received ≥2 grafts/patients on the anterolateral territory. The graft patency (i.e. non-occluded) was assessed using multislice spiral computed tomography at 1 year. RESULTS: From 2012 to 2021, 208 patients were randomized to a bridge (n = 105) or conventional grafting strategy (n = 103). Patient characteristics were comparable between groups. The anterolateral graft patency was non-inferior in the composite bridge compared to conventional grafting strategy at 1 year [risk difference 0.7% (90% confidence interval -4.8 to 6.2%)]. The graft patency to the left anterior descending coronary was no different between groups (P = 0.175). Intraoperatively, the bridge group required shorter vein length for anterolateral targets (P < 0.001) and exhibited greater Doppler flow in the mammary artery pedicle (P = 0.004). The composite outcome of death, myocardial infarction or target vessel reintervention at 30 days was no different (P = 0.164). CONCLUSIONS: Anterolateral graft patency of the composite bridge grafting strategy is non-inferior to the conventional grafting strategy at 1 year. This novel grafting strategy is safe, efficient, associated with several advantages including better mammary artery flow and shorter vein requirement, and could be a valuable alternative to conventional grafting strategies. Ten-year clinical follow-up is underway. TRIAL REGISTRATION: ClinicalTrials.gov: NCT01585285.

Off-pump Versus On-pump Coronary Artery Bypass Surgery: Graft Patency Assessment With Coronary Computed Tomographic Angiography: A Prospective Multicenter Randomized Controlled Pilot Study.

PURPOSE: A large multicenter randomized trial (RCT) is needed to assess off-pump coronary artery bypass graft (CABG) patency when performed by skilled surgeons. This prospective multicenter randomized pilot study compares graft patency after on-pump and off-pump techniques and addresses the feasibility of such an RCT. MATERIALS AND METHODS: Consecutive patients were prospectively recruited for ≥64-slice computed tomography angiography graft patency assessment 1 year after randomization to off-pump or on-pump CABG. Blinded assessment of graft patency was performed, and the results were categorized as normal, ≥50% stenosis, or occlusion. A multilevel model with random effects on the patient was used to account for correlation of results in patients with multiple grafts. RESULTS: A total of 157 patients (3 centers, 84 off-pump and 73 on-pump patients, 512 grafts, assessability rate 98.4%) were included. Patency index (% nonoccluded grafts) was 89% for the off-pump technique and 95% for the on-pump technique (P=0.09). Patency was similar for arterial and vein grafts (both 92%; P=0.88), as well as between target territories (89% to 94%; P=0.53). CONCLUSIONS: In this pilot study, 1-year graft patency results after off-pump and on-pump surgery were similar. This feasibility trial demonstrates that a large multicenter RCT to compare CABG patency after on-pump with that after off-pump techniques is feasible and can be reliably undertaken using computed tomography angiography.

A morphometric 3D model of coronary artery bypass graft dysfunction with multidetector computed tomography.

OBJECTIVE: The objective was to assess, with computed tomography (CT) angiography, quantitative morphological parameters of a composite coronary artery bypass grafting (CABG) strategy and to correlate these with graft dysfunction. FINDINGS: Forty patients [median postoperative time, 32 (14-51) months] underwent CT angiography. Graft patency was assessed, and specific quantitative morphological parameters of the graft were collected. Graft segments had an overall patency rate of 93% (78/84). Two specific morphological parameters were found to be associated with graft dysfunction. CONCLUSION: A CT morphometric model can be used to identify quantitative 3D parameters associated with graft dysfunction. Such an approach could help in developing and improving CABG designs.

Intra-operative graft blood flow measurements for composite and sequential coronary artery bypass grafting.

OBJECTIVES: Intraoperative assessment of coronary artery bypass grafts (CABG) anastomotic quality can be performed using transit-time flowmetry (TTF). The aim of this study was to compare on- versus off-pump coronary graft TTF and early postoperative outcomes. MATERIALS AND METHODS: Between January 2009 and January 2010, 521 distal graft flows were assessed using TTF measurements in 253 consecutive patients undergoing primary isolated CABG surgery. Data were analyzed using multilevel models accounting for clustering among surgeons and grafts performed in the same patient. RESULTS: Mean age was 66 ± 10 years and 22% were female (n = 55) with 34% diabetics (n = 86) and 40% preoperative myocardial infarction (MI) (n = 101). The surgeries were performed off-pump in 67% (n = 170) with sequential vein grafts in 57% (n = 144) of patients. Off-pump patients had higher pre-operative left ventricular ejection fractions (LVEF), fewer urgent surgeries, fewer distal anastomoses, and fewer sequential vein grafts (all p<0.001). Intra-operative coronary graft TTF measurements were lower in sequential vein grafts performed off-pump versus on-pump. More patients in the on-pump group needed milrinone or dobutamine 24-48 h postoperatively (p = 0.005). Independent predictors of lower TTF included female gender and off-pump surgery, whereas predictors of better TTF were preoperative MI, larger coronary diameter at the site of the distal anastomosis, and sequential vein grafting. CONCLUSIONS: Lower intra-operative TTF measurements were found in sequential vein grafts in off-pump CABG. However, off-pump patients experienced similar short-term outcomes compared to on-pump patients.

Composite versus conventional coronary artery bypass grafting strategy for the anterolateral territory: study protocol for a randomized controlled trial.

BACKGROUND: In severe coronary artery disease, coronary artery bypass grafting (CABG) surgery is indicated to re-establish an adequate blood supply to the ischemic myocardium. Effectiveness of CABG surgery for symptom relief and mortality decrease should therefore depend on bypass graft patency. As bypass using a left internal mammary artery (LIMA)-to-left anterior descending coronary artery (LAD) anastomosis allows the best results in terms of graft patency, we designed a new surgical technique using a saphenous vein graft as a venous bridge to distribute the LIMA flow to the cardiac anterolateral territory. This novel strategy could extend the patency benefits associated to the LIMA. Other potential benefits of this technique include easier surgical technique, possibility to use saphenous vein grafts as vein patch angioplasty, shorter saphenous vein grafts requirement and reduced or eliminated manipulations of the ascendant aorta (and associated stroke risk). METHODS/DESIGN: Between July 2012 and 2016, 200 patients undergoing a primary isolated CABG surgery using cardiopulmonary bypass with a LAD bypass graft and at least another target on the anterolateral territory will be randomized (1:1) according to 1) the new composite strategy and 2) the conventional strategy with a LIMA-to-LAD anastomosis and revascularization of the other anterolateral target(s) with a separated aorto-coronary saphenous vein graft. The primary objective of the trial is to assess whether the composite strategy allows non-inferior anterolateral graft patency index (proportion of non-occluded CABGs out of the total number of CABGs) compared to the conventional technique. The primary outcome is the anterolateral graft patency index, evaluated at one year by 256-slice computed tomography angiography. Ten years of clinical follow-up is planned to assess clinical outcomes including death, myocardial infarction and need for revascularization. DISCUSSION: This non-inferiority trial has the potential to advance the adult cardiac surgery field, given the potential benefits associated with the composite grafting strategy. TRIAL REGISTRATION: ClinicalTrials.gov: NCT01585285.

A novel composite coronary bypass graft strategy: the saphenous vein bridge--a pilot study.

OBJECTIVES: The aim of this pilot study was to describe and assess the safety of a novel composite graft technique for coronary artery bypass grafting (CABG) surgery. A saphenous vein is grafted to the left anterior descending artery (LAD) and other anterolateral coronary arteries, creating a saphenous vein bridge (SVB) and the left internal mammary artery (LIMA) is anastomosed to the SVB, distributing the blood flow distally (LIMA-SVB). METHODS: All patients who underwent CABG with the LIMA-SVB between 2005 and 2008 at our centre were enrolled in this study. Perioperative data were retrospectively collected from hospital charts, and the clinical follow-up was completed by telephone interview. Graft patency was assessed by computed tomography angiography (CTA) in patients with the longest follow-up time (n = 20). RESULTS: A total of 256 patients (mean age: 67 ± 12 years; 79% male) received 4.0 ± 1.0 grafts, including 2.2 ± 0.4 distal grafts provided by the LIMA-SVB. Nine (3.5%) deaths and 4 (1.6%) myocardial infarctions (MIs) were noted in the perioperative period. With a median follow-up time of 36 months [inter-quartile range 31-44], 1 (0.5%) MI and 2 (1.0%) strokes were reported. At 51 months post-surgery [47-53], CTA demonstrated a LIMA pedicle (n = 20) and SVB (n = 42) patency rate of 100 and 93%, respectively. Specifically, the LIMA-SVB patency rate was 100% to the LAD and 85% to diagonal arteries. Aortocoronary vein grafts (n = 38) patency rate in the same patients was 87%. CONCLUSIONS: Revascularization of the anterolateral territory using the LIMA-SVB is a promising approach considering its clinical safety and favourable patency rate results. A prospective randomized clinical trial is underway to compare this technique to conventional CABG.

Epidural anesthesia improves outcome and resource use in cardiac surgery: a single-center study of a 1293-patient cohort.

Thoracic epidural anesthesia (TEA) combined with general anesthesia in cardiac surgery has the potential to initiate earlier spontaneous ventilation and extubation, improved hemodynamics, less arrhythmia or myocardial ischemia, and an attenuated neurohormonal response. The aim of the current study was to characterize the correlation between TEA and postoperative resource use or outcome in a consecutive-patient cohort. The study was performed in a tertiary care, 3-surgeon, university-affiliated hospital that performs 350 to 400 cardiac surgeries per year. All 1293 adult patients who underwent cardiac surgery between July 1, 2002, and February 1, 2006, were included. Patients were assigned to anesthesiologists practicing TEA (TEA group, n = 506) or not (control group, n = 787) for cardiac surgery. The preoperative parameter values and Parsonnet scores for the 2 groups were similar. The 2 groups had the same distribution of surgery types. The TEA group presented with fewer intensive care unit (ICU) complications, such as delirium, pneumonia, and acute renal failure, and presented with better myocardial protection. The TEA group presented with a higher proportion of immediately postoperative extubations and with shorter ventilation times and ICU stays. Total ICU costs decreased from US $18,700 to $9900 per patient. Combining TEA and general anesthesia for cardiac surgery allows a significant change in anesthesia strategy. This change improves immediate postoperative outcomes and reduces the use and costs of ICU resources.

Awake cardiac surgery using a novel anesthetic technique.

PURPOSE: We describe the first published cases of awake cardiac surgery in Canada. In addition, a novel anesthetic technique consisting of combined femoral block/high epidural thoracic anesthesia is presented. CLINICAL FEATURES: Two patients, both 65 yr of age and with good left ventricular function, were scheduled to undergo off-pump coronary artery bypass grafting (OPCAB) for two grafts each. Anesthesia consisted of combined femoral 3:1 block and high thoracic epidural anesthesia. Both surgeries proceeded without hemodynamic or respiratory complications; in both cases, opening of the pleural spaces was treated with insertion of thoracic drainage tubes. Both patients were transferred to the postanesthesia care unit immediately after surgery and six hours later to the cardiac surgical ward. Both patients were discharged from the hospital within five days of surgery. CONCLUSION: We conclude that awake OPCAB is feasible using a combined femoral block/high thoracic epidural anesthesia technique which allows cardiac surgery and harvesting of the saphenous vein. Further clinical experience is required to define the technical limitations of this technique before randomized studies should be undertaken to better define the role of awake procedures in the future of cardiac surgery.

Immediate extubation after aortic valve surgery using high thoracic epidural analgesia or opioid-based analgesia.

OBJECTIVE: Fast-track anesthesia has gained widespread use in cardiac centers around the world. No study has been published focusing on immediate extubation after aortic valve surgery. This study examines the feasibility and hemodynamic stability of immediate extubation after simple or combined aortic valve surgery using either thoracic epidural analgesia or opioid-based analgesia. DESIGN: Prospective audit, pilot study. SETTING: Single-institution university medical center. PARTICIPANTS: Adult patients undergoing aortic valve replacement (N = 45). INTERVENTIONS: Forty-five patients undergoing aortic valve surgery with an ejection fraction of more than 30% were included in this prospective audit. Induction of anesthesia was done using fentanyl, 2 to 4 mug/kg, propofol, 1 to 2 mg/kg, and endotracheal intubation facilitated by rocuronium; anesthesia was maintained using sevoflurane titrated according to bispectral index (BIS [BIS target: 50]). Perioperative analgesia was provided by high thoracic epidural analgesia (TEA group, bupivacaine 0.125%, 6 to 14 mL/h) or fentanyl, up to 10 microg/kg, followed by patient-controlled analgesia with morphine (OPIOID group). MEASUREMENTS AND MAIN RESULTS: Success of extubation within 30 minutes after surgery was recorded. Hemodynamic data during surgery were compared by using an analysis of variance test; p < 0.05 was considered as showing a significant difference. Data presented as median (25th-75th percentile). In the TEA group, patients underwent simple aortic valve replacement (N = 21) or combined aortic valve surgery (N = 14), with additional coronary artery bypass grafting (N = 10) and replacement of the ascending aorta (Bentall, N = 4). In the OPIOID group, patients underwent simple aortic valve replacement (N = 5) or combined aortic valve surgery (N = 5), with additional aortocoronary bypass grafting (N = 2), replacement of the ascending aorta (Bentall, N = 2), and reconstruction of the mitral valve (N = 1). All 45 patients were extubated within 15 minutes after surgery. There was no need for reintubation; pain scores were lower in the TEA group than in the OPIOID group immediately after surgery and at 6 hours, 24 hours, and 48 hours after surgery. For the TEA group and OPIOID group, the pain scores were 0 (0-2), 0 (0-2), 0 (0-1.5), and 0 (0-0) and 5 (4-5.75), 4 (3-4.5), 4 (3.25-4), and 1 (0-2.5), respectively. During and up to 6 hours after surgery, there was no significant hemodynamic difference between the TEA and OPIOID groups. Eighteen of 45 patients needed temporary pacemaker activation. There were no epidural hematoma or neurologic complications related to TEA. CONCLUSION: Immediate extubation is feasible after aortic valve surgery using either high thoracic epidural analgesia or opioid-based analgesia; both techniques maintain hemodynamic stability throughout surgery. TEA provides superior pain control.

Bispectral index as an indicator of cerebral hypoperfusion during off-pump coronary artery bypass grafting.

Bradycardia and hypotension are common during off-pump coronary artery bypass grafting (OPCAB). We present a case of possible reversible global cerebral hypoperfusion during distal grafting of the left circumflex coronary artery. The bispectral index (BIS) suddenly decreased from values of 45-50 to 0 during distal grafting. Neurologic evaluation after immediate tracheal extubation in the operating room was normal and the 58 yr old patient did not suffer any neurologic sequelae. Postoperative recovery was uneventful and the patient was discharged 5 days after surgery. Cerebral hypoperfusion is a possible complication during OPCAB. BIS monitoring in OPCAB could be an indicator of cerebral hypoperfusion.

Immediate Extubation after Aortic Valve Surgery Using High Thoracic Epidural Anesthesia.

Abstract Purpose: Fast-track anesthesia has gained widespread use in cardiac centers around the world. No study has focused on immediate extubation after aortic valve surgery. This study examines the feasibility and hemodynamic stability of immediate extubation after simple or combined aortic valve surgery using thoracic epidural anesthesia. Methods: Thirty patients undergoing aortic valve surgery with an ejection fraction of more than 30% were included in this prospective audit. After insertion of a high thoracic epidural catheter, induction with fentanyl 2 to 4 microg/kg, administration of propofol 1 to 2 mg/kg, and endotracheal intubation facilitated by rocuronium, anesthesia was maintained with sevoflurane titrated according to bispectral index (target, 50). Perioperative analgesia was provided by high thoracic epidural analgesia (TEA) (bupivacaine 0.125% 6-14 mL/h). Hemodynamic data were compared by Friedman test. P <.05 was considered to show a significant difference. Data are presented as median (25th-75th percentile). Results: Patients underwent simple aortic valve surgery (n = 17) or combined aortic valve surgery (n = 13) with additional coronary artery bypass grafting (n = 8), replacement of the ascending aorta (Bentall procedure) (n = 4), and repair of open foramen ovale (n = 1). All 30 patients were extubated within 15 minutes after surgery at 36.5 degrees C (36.4 degrees C-36.6 degrees C). There was no need for reintubation. Pain scores were low immediately after surgery and 6, 24, and 48 hours after surgery at 0 (0-3.5), 0 (0-2), 0 (0-2), and 0 (0-2), respectively. During and up to 6 hours after surgery, there was no significant hemodynamic change due to TEA. Fifteen of 30 patients needed temporary pacemaker activation. There were no complications related to TEA. Conclusions: Immediate extubation is feasible after aortic valve surgery with high thoracic epidural analgesia and maintenance of hemodynamic stability throughout surgery. Immediate extubation after aortic valve surgery is a promising new path in cardiac anesthesia.

Ultra-fast-track anesthesia in off-pump coronary artery bypass grafting: a prospective audit comparing opioid-based anesthesia vs thoracic epidural-based anesthesia.

PURPOSE: To examine the feasibility of immediate extubation after off-pump coronary artery bypass grafting (OPCAB) using opioid based analgesia or high thoracic epidural analgesia (TEA) and compare postoperative analgesia with continuous TEA vs patient-controlled analgesia (PCA). METHODS: One hundred consecutive patients undergoing OPCAB were included in this prospective audit. After induction of anesthesia using fentanyl 2 to 5 microg.kg(-1), propofol 1 to 2 mg.kg(-1) and endotracheal intubation facilitated by rocuronium, anesthesia was maintained using sevoflurane titrated according to bispectral index monitoring. Perioperative analgesia was provided by TEA (n = 63) at the T3/T4 interspace or T4/T5 interspace using bupivacaine 0.125% 8 to 14 mL.hr(-1) and repetitive boluses of bupivacaine 0.25% during surgery. In patients who were fully anticoagulated or refused TEA, perioperative analgesia was achieved by i.v. fentanyl boluses (up to 15 microg.kg(-1)) and remifentanil 0.1 to 0.2 microg.kg(-1).min(-1), followed by morphine PCA after surgery (n = 37). Maintenance of body temperature was achieved by a heated operating room and forced-air warming blankets. RESULTS: Ninety-five patients were extubated within 25 min after surgery (PCA, n = 33; TEA, n = 62). Five patients were not extubated immediately because their core temperature was lower than 35 degrees C. One patient was re-intubated because of agitation (TEA group); one was re-intubated because of severe pain and morphine-induced respiratory depression (PCA group). Pain scores were low after surgery, with pain scores in the TEA group being significantly lower immediately, at six hours, 24 hr and 48 hr after surgery (P < 0.05). CONCLUSION: Immediate extubation is possible after OPCAB using either opioid-based analgesia or TEA. TEA provides significantly lower pain scores after surgery in comparison to morphine PCA.