Implications of Elevated Serum Cortisol in the Onset of Postoperative Delirium Following Off-Pump Coronary Artery Bypass Grafting: Insights from a Bangladesh-Based Single Center Experience

Background: Following coronary artery bypass grafting (CABG), delirium emerges as a prevalent complication. This study aimed to assess the correlation between elevated serum cortisol levels and the occurrence of postoperative delirium subsequent to off-pump CABG. Methods: Conducted in the Department of Cardiac Surgery at BSMMU from October 2020 to September 2022, this comparative cross-sectional study included a total of 44 participants. Subjects, meeting specific criteria, were purposefully assigned to two groups based on off-pump CABG. Group A (n = 22) consisted of patients with normal serum cortisol levels, while Group B (n = 22) comprised individuals with high serum cortisol levels on the first postoperative day. Delirium onset was assessed at the bedside in the ICU on the 1st, 2nd, 3rd, 4th, and 5th postoperative days using standard tools, namely the Richmond Agitation Sedation score (RASS) and The Confusion Assessment Method (CAM-ICU). Data were collected based on the presence or absence of delirium. Statistical analysis utilized SPSS version 26.0, employing an independent Student’s t-test for continuous data and chi-square and Fischer’s exact test for categorical data. A p-value ≤ 0.05 was considered statistically significant. Results: Group-A had a mean age of 54.50 ± 17.97, and Group-B had a mean age of 55.22 ± 15.45, both with a male predominance (81.81% and 86.36% respectively). The mean serum cortisol level was significantly higher in Group B (829.71 ± vs. 389.98 ± 68.77). Postoperative delirium occurred in 27.3% of Group B patients, statistically significant compared to the 4.5% in Group A. However, patients in Group B who developed delirium experienced significantly longer postoperative ICU and hospital stays (79.29 ± 12.27 vs. 11.44 ± 2.85, p ≤ 0.05). There was one mortality in Group B, which was statistically not significant. Conclusion: This study observed a significant association between elevated serum cortisol levels in the postoperative period and the occurrence of postoperative delirium after off-pump coronary artery bypass grafting.

Off-Pump Coronary Artery Bypass Grafting in Patients with Left Ventricular Dysfunction: Short-Term Results from a Single Center in Bangladesh

Background: Off-pump coronary artery bypass grafting (OPCAB) is considered a safer alternative to on-pump surgery, especially in patients with left ventricular dysfunction (LVD). Objectives: This study assessed short-term outcomes and functional improvements in LVD patients post-OPCAB. Methods: The study included 200 coronary artery disease patients who underwent isolated off-pump coronary artery bypass grafting (OPCAB) at the National Heart Foundation Hospital and Research Institute between January 2019 and June 2020. Patients were categorized into Group 1, with a left ventricular ejection fraction (LVEF) of 30% - 39%, and Group 2, with an LVEF of 40% or higher. Echocardiographic assessments of left ventricular dimensions and ejection fraction were performed preoperatively, at discharge, and one month postoperatively. Results: In Group 1, preoperative left ventricular internal dimensions during diastole (LVIDd) and systole (LVIDs) were 53.48 ± 4.40 mm and 44.23 ± 3.93 mm, respectively, with a left ventricular ejection fraction (LVEF) of 35.28% ± 2.26%. At discharge, these values improved to 51.58 ± 4.04 mm (LVIDd), 41.23 ± 5.30 mm (LVIDs), and 39.25% ± 3.75% (LVEF). One month postoperatively, further improvements were observed: 46.29 ± 3.76 mm (LVIDd), 37.45 ± 3.68 mm (LVIDs), and 43.22% ± 4.67% (LVEF). Group 2 showed similar positive outcomes, with preoperative values of 47.09 ± 5.06 mm (LVIDd), 35.11 ± 5.25 mm (LVIDs), and 50.13% ± 7.25% (LVEF), improving to 42.37 ± 4.18 mm (LVIDd), 31.05 ± 4.19 mm (LVIDs), and 55.33% ± 7.05% (LVEF) at one month postoperatively. Both groups demonstrated significant improvements in left ventricular function and NYHA class, with most patients moving from class III/IV to I/II. Complications were minimal, and no mortality was observed. Conclusion: OPCAB is safe and effective for patients with LVEF 30% - 39% and LVEF ≥ 40%, providing significant short-term functional improvements without increased risk.

Impact of specialized nursing outpatient case management on postcoronary artery bypass grafting patients

BACKGROUND Some patients with coronary atherosclerotic heart disease experience major adverse cardiac events(MACE)and require readmission after Coronary Artery Bypass Grafting(CABG)surgery.This is often attributed to patients'unhealthy lifestyles and dietary habits,inadequate understanding of the disease,and poor disease management compliance.Thus,searching for more targeted nursing intervention models that can enhance patients'self-management abilities and reduce the risk of readmission after CABG surgery is significant.AIM To observe the impact of specialized nursing outpatient case management on patients after CABG surgery.METHODS A total of 103 patients who underwent CABG surgery in our hospital between April 2021 and April 2022 comprised the study sample.The patients were divided into two groups using an odd-even number grouping method.The control group received routine nursing care,while the case management group received specialized nursing outpatient case management.The differences in psychological status,adherence to medical treatment,self-care ability,knowledge mastery,quality of life scores,and the occurrence rate of MACE were compared between the two groups.RESULTS After the intervention,the case management group had lower scores on the selfrating depression scale and self-rating anxiety scale and lower MACE rate,as well as higher scores for adherence to a healthy diet,medication adherence,good lifestyle habits,regular exercise,and timely follow-up,higher scores on the Coronary Heart Disease Self-Management Scale,higher scores for managing adverse habits,symptoms,emotional cognition,emergency response,disease knowledge,general lifestyle,and treatment adherence,higher scores for understanding coronary heart disease,recognizing the importance of medication adherence,understanding selfcare points after CABG surgery,and being aware of post-CABG precautions,higher scores for physical well-being,disease condition,general health,social-psychological well-being,and work-related aspects(P<0.05).CONCLUSION Specialized nursing outpatient case management can enhance patient adherence to medical treatment,knowledge mastery,psychological well-being,and overall quality of life in patients after CABG surgery.

Preoperative Serum Albumin Levels and Postoperative Acute Kidney Injury in Off-Pump Coronary Artery Bypass Surgery: A Single-Center Study in Bangladesh

Background: Serum albumin, a vital plasma protein, helps maintain intravascular colloidal osmotic pressure, cardiac output, and renal function. Low preoperative serum albumin is linked to poor outcomes, including acute kidney injury (AKI), after off-pump coronary artery bypass (OPCAB) surgery. This study aimed to assess the relationship between preoperative serum albumin levels and early postoperative renal injury. Methods: This prospective comparative cross-sectional study was conducted from August 2019 to February 2021 at the National Heart Foundation Hospital & Research Institute, Bangladesh. It included 160 adult patients with normal preoperative renal function undergoing OPCAB. Patients were divided into two groups: Group A (serum albumin ≥ 4.0 gm/dl) and Group B (serum albumin Results: Preoperative serum albumin was significantly different between groups (Group A: 4.21 ± 0.05 gm/dl, Group B: 3.69 ± 0.04 gm/dl, p = 0.028). Group B had a higher incidence of hypertension (71.25% vs. 51.25%, p st and 3rd postoperative days were higher in Group B (p th day. Postoperative AKI occurred in 18.75% of Group A and 36.25% of Group B. Multivariate regression indicated that low preoperative serum albumin is an independent risk factor for postoperative AKI (p = 0.012, OR = 1.815, CI: 0.675 - 1.162). Conclusion: Preoperative serum albumin level is a valuable predictor of postoperative renal function. Ensuring high normal serum albumin levels before surgery can help minimize the risk of postoperative AKI.

Impact of coronary artery bypass grafting surgery on the chorioretinal biomicroscopic characteristics

BACKGROUND Most patients with cardiovascular disorders suffer from coronary artery diseases,which can be treated successfully using coronary artery bypass grafting(CABG).One of the unpleasant events following CABG is postoperative vision loss(POVL).Vulnerability of retinal vessels to hemodynamic changes,an expectable event following CABG,may contribute to the development of POVL,which might be associated with the changes in the choroidal and retinal structures.AIM To investigate postoperative changes in chorioretinal and peripapillary nerve fiber layer(NFL)thickness,and progression of diabetic and hypertensive retinopathy after CABG.METHODS In this prospective,cross-sectional study,49 eyes in 25 candidates for CABG underwent both ophthalmic and cardiovascular examinations within 6 mo prior to and 9 mo after surgery.RESULTS Among the study participants,56%were male with a mean age of 62.84 years±10.49 years(range 33–80 years).Diabetes mellitus was observed in eight participants(32%).None of the patients suffered from postoperative anterior or posterior ischemic optic neuropathy,central retinal artery occlusion,and cortical blindness.The mean value of the preoperative best corrected visual acuity was 0.11±0.10 logMAR(range,0–0.4),which worsened to 0.15±0.08 logMAR(range,0–0.4)after CABG(P=0.031).No significant difference was observed between the preand postsurgical choroidal(P=0.853)and macular(P=0.507)thickness,NFL thickness in the subfoveal(P>0.999)and peripapillary areas(P=0.659),as well as the severity of diabetic and hypertensive retinopathy.CONCLUSION CABG may reduce visual acuity without affecting ocular structures.Postoperative vision reduction might be attributable to molecular or cellular variations,changes in visual pathway function,or central nervous system.

Long-Term Outcomes after Coronary Artery Bypass Grafting with Risk Stratification

Background: Risk stratification of long-term outcomes for patients undergoing Coronary artery bypass grafting has enormous potential clinical importance. Aim: To develop risk stratification models for predicting long-term outcomes following coronary artery bypass graft (CABG) surgery. Methods: We retrospectively revised the electronic medical records of 2330 patients who underwent adult Cardiac surgery between August 2016 and December 2022 at Madinah Cardiac Center, Saudi Arabia. Three hundred patients fulfilled the eligibility criteria of CABG operations with a complete follow-up period of at least 24 months, and data reporting. The collected data included patient demographics, comorbidities, laboratory data, pharmacotherapy, echocardiographic parameters, procedural details, postoperative data, in-hospital outcomes, and follow-up data. Our follow-up was depending on the clinical status (NYHA class), chest pain recurrence, medication dependence and echo follow-up. A univariate analysis was performed between each patient risk factor and the long-term outcome to determine the preoperative, operative, and postoperative factors significantly associated with each long-term outcome. Then a multivariable logistic regression analysis was performed with a stepwise, forward selection procedure. Significant (p < 0.05) risk factors were identified and were used as candidate variables in the development of a multivariable risk prediction model. Results: The incidence of all-cause mortality during hospital admission or follow-up period was 2.3%. Other long-term outcomes included all-cause recurrent hospitalization (9.8%), recurrent chest pain (2.4%), and the need for revascularization by using a stent in 5 (3.0%) patients. Thirteen (4.4%) patients suffered heart failure and they were on the maximum anti-failure medications. The model for predicting all-cause mortality included the preoperative EF ≤ 35% (AOR: 30.757, p = 0.061), the bypass time (AOR: 1.029, p = 0.003), and the duration of ventilation following the operation (AOR: 1.237, p = 0.021). The model for risk stratification of recurrent hospitalization comprised the preoperative EF ≤ 35% (AOR: 6.198, p p = 0.023), low postoperative cardiac output (AOR: 3.622, p = 0.007), and the development of postoperative atrial fibrillation (AOR: 2.787, p = 0.038). Low postoperative cardiac output was the only predictor that significantly contributed to recurrent chest pain (AOR: 11.66, p = 0.004). Finally, the model consisted of low postoperative cardiac output (AOR: 5.976, p < 0.001) and postoperative ventricular fibrillation (AOR: 4.216, p = 0.019) was significantly associated with an increased likelihood of the future need for revascularization using a stent. Conclusions: A risk prediction model was developed in a Saudi cohort for predicting all-cause mortality risk during both hospital admission and the follow-up period of at least 24 months after isolated CABG surgery. A set of models were also developed for predicting long-term risks of all-cause recurrent hospitalization, recurrent chest pain, heart failure, and the need for revascularization by using stents.

Using Magnesium Sulfate to Prevent Atrial Fibrillation after Coronary Artery Bypass Grafting Surgery: A Single Centre Experience in Bangladesh

Background: Atrial fibrillation commonly occurs following cardiac surgery, particularly after coronary artery bypass grafting. Magnesium, known for its stabilizing effect on cell membranes, has shown promise in preventing postoperative atrial fibrillation. This study aimed to assess the impact of intravenous magnesium infusion in preventing atrial fibrillation after off-pump coronary artery bypass grafting, where maintaining stable cell membranes is crucial in averting this complication. Methods: A cross-sectional study was conducted at the Department of Cardiac Surgery, Bangabandhu Sheikh Mujib Medical University, from March 2020 to February 2022. Sixty-six patients who underwent off-pump coronary artery bypass grafting were enrolled and divided into two groups. Group A (n = 33) received intravenous magnesium sulfate (10 mmol/2.47gm) for three days after surgery, while Group B (n = 33) did not receive magnesium sulfate. Postoperative atrial fibrillation occurrence in the Intensive Care Unit (ICU) within three days after surgery was evaluated using convenient sampling. Statistical analysis was performed with SPSS version 26.0, utilizing independent Student’s t-test for continuous data and Chi-square and Fisher’s exact test for categorical data. A p-value of ≤0.05 was considered statistically significant. Results: No significant differences in age or gender were observed between the two groups. Group B exhibited significantly lower magnesium levels than Group A on the 0th, 1st, 2nd, and 3rd days post-surgery. Additionally, Group B experienced a higher incidence of postoperative atrial fibrillation, longer ICU stays, and two mortalities. The study did not detect any adverse effects associated with magnesium infusion. Conclusion: It has been demonstrated that administering magnesium intravenously after off-pump coronary artery bypass grafting can lower the chances of developing atrial fibrillation. This demonstrates the potential advantages of using magnesium as a preventative measure for postoperative atrial fibrillation in such cases.

Off-pump coronary artery bypass grafting using a bilateral internal mammary artery Y graft

Objective To evaluate the outcome of off-pump coronary artery bypass grafting （OPCABG） using a bilateral internal mammary artery （BIMA） Y configuration graft to achieve total arterial myocardial revascularization. Methods From October 2002 to December 2008, 208 patients （196 males and 12 females） underwent OPCABG using a BIMA Y configuration graft. The average age of the patients was 56.5 ± 11.3 years, with an age range of 33-78 years. A total of 167 （80.2%） cases had triple-vessel disease. Left main stem disease was found in 33 （15.9%） cases, and double-vessel disease was found in 8 （3.9%） cases. The semi-skeletonization technique was used to harvest the two internal mammary arteries （IMAs）, and then the free right internal mammary artery was connected end-to-side to the left internal mammary artery （LIMA） in situ to complete the Y configuration graft. Off-pump and sequential anastomosis methods were used to perform coronary artery bypass surgery in all patients. Graft patency was assessed intm-operatively with the HT311 transit time flowmeter. Results A total of 728 distal anastomoses were performed in 208 patients, with the average being 3.5± 1.3 per person. No one died or experienced recurrent angina within 30 days after the operation. Conclusions OPCABG using the BIMA Y graft was safe and effective to achieve total arterial revascularization. This method avoids surgical operation on the ascending aorta and other incisions.

Off-pump coronary artery bypass grafting versus on-pump coronary artery bypass grafting： which is better in patients with chronic obstructive pulmonary disease？

To evaluate the clinic outcome of off-pump coronary bypass grafting (OPCABG) of patients with coronary heart disease and chronic obstructive pulmonary disease, we collected and analyzed 1998-2002 data on 28 patients with these two diseases who had received off-pump coronary bypass operation in our hospital, and compared with data on those who also had the same two diseases but received on-pump coronary artery bypass at same time. There were no operation-related death;one died of respiratory failure 14 days after operation while staying in hospital; there were more respiratory complications in the conventional coronary artery bypass grafting group (CCABG) than in the OPCABG group; and the PaO2/FiO2 in the CCABG group was higher than that in the OPCABG group during operation because of CPB, but lower than that in the OPCABG group 6-12 hours after operation. OPCABG seemed more suitable than CCABG for coronary artery disease patients with chronic obstructive pulmonary disease due to less damage to their oxygen-exchange capability and the fewer respiratory complications.

Redo Coronary Artery Bypass Grafting: On-Pump and Off-Pump Coronary Artery Bypass Grafting Revascularization Techniques

Objective To analyze the short-term outcomes of redo coronary artery bypass grafting(CABG) using on-pump and off-pump CABG techniques. Methods From January 2003 to August 2013, non-randomized 80 patients were treated with redo CABG in the Department of Cardiac Surgery, Peking University Third Hospital. Among these patients, 40 underwent on-pump CABG technique(redo-ONCAB group) and 40 underwent off-pump CABG technique(redo-OPCAB group). Furthermore, transmyocardial laser revascularization was performed in high-risk patients who were not suitable to conventional grafting. Clinical data of the two groups were recorded and analyzed including operation time, coronary grafts, incomplete revascularization, postoperative ventilation, perioperative stroke, and low output syndrome, etc. Results There were no significantly differences in age, gender distribution, incidences of hypertension, stroke, and other clinical characteristics between redo-OPCAB group and redo-ONCAB group(all P>0.05), except for incidences of renal dysfunction and pulmonary disease(all P<0.05). The number of grafting vessels in the redo-ONCAB and redo-OPCAB groups was 2.1 ± 0.74 and 1.4 ±0.52 respectively. There was significant difference between the two groups(P=0.0243). Compared with the redo-ONCAB group, there was shorter operation time(P=0.0045), postoperative ventilation(P=0.0211) and intensive care unit stay(P=0.0400), as well as fewer use of platelet(P=0.0338) and blood transfusion(P=0.0034) in the redo-OPCAB group. The incidence of incomplete revascularization(P=0.0253) and the use of transmyocardial laser revascularization(P=0.0052) were higher in the redo-OPCAB group than those in the redo-ONCAB group(all P<0.05). However, no significant differences were showed for the incidence of the use of intra aortic balloon pump and continuous renal replacement therapy, perioperative stroke, low output syndrome, and in-hospital mortality between the two groups(all P>0.05). Conclusion Redo CABG is the safety and efficacy surgical procedure, and redo-OPCAB technique with better outcomes is commended especially in high-risk patients.

Off-pump coronary artery bypass grafting versus optimal medical therapy alone：effectiveness of incomplete revascularization in high risk patients

BackgroundGeriatric patients with multivessel coronary artery disease （CAD） are a challenging group to treat; these cases elicit dis-cussion within heart teams regarding the actual benefit of undertaking major surgery on these patients and often lead to abandon the surgical option. Percutaneous procedures represent an important option, but coronary anatomy may be unfavorable. Off-pump coronary artery bypass （OPCAB） provides good quality graft on left anterior descending （LAD） without exposing the patient to cardiopulmonary bypass, and might be the ideal choice in patients with multiple comorbidities, not eligible to percutaneous or on-pump procedures. The objective of this study was to compare survival during a mid-term follow-up in high-risk patients with no percutaneous alternative, either treated with OPCAB or discharged in medical therapy.MethodsWe retrospectively evaluated from June 2008 to June 2013, 83 high-risk patients with multivessel CAD were included： 42 were treated with incomplete off-pump revascularization using left internal mammary artery （LIMA） on LAD; 41 were discharged in optimal medical therapy （OMT）, having refused surgery. Follow-up ended in March 2015, with a telephonic interview. Primary endpoint was survival from all-cause mortality; secondary endpoints were survival from cardiac-related mortality and freedom from non-fatal major adverse cardiac events （MACEs）.ResultsDuring follow up, 11 deaths in OPCAB group and 27 deaths in OMT group occurred. Death was due to cardiac factors in 6 and 15 patients, respectively. MACEs were observed in 6 patients in OPCAB group and in 4 patients in OMT group. With regards to survival from all-cause mortality, patients who underwent OPCAB survived more than those dis-charged in OMT （Log Rank ＆lt; 0.001）, and OMT group carries a propensity score-adjusted hazard ratio of 3.862 （P ＆lt; 0.001）. With regards to survival from cardiac-related events, patients who underwent OPCAB survived more than those discharged in OMT （Log Rank = 0.002）, and OMT group carries a propensity score-adjusted hazard ratio of 3.663 （P = 0.010）. There is no statistically significant difference concerning freedom from MACEs （Log Rank = 0.273）.ConclusionsFor high-risk patients with multivessel CAD, not eligible to on-pump complete revascularization surgery or percutaneous procedures, incomplete revascularization with OPCAB LIMA-on-LAD offers benefits in survival when compared to OMT alone.

Off-pump coronary artery bypass grafting: Misperceptions and misconceptions

Coronary artery bypass grafting(CABG) continues to be one of the most commonly performed cardiac surgical procedures worldwide. Conventional CABG performed on cardiopulmonary bypass termed on-pump CABG is regarded as the gold standard. However, on-pump CABG results in several physiologic derangements including but not limited to thrombocytopenia, activation of complement factors, immune suppression, and inflammatory responses leading to organ dysfunction.Furthermore, manipulating an atherosclerotic ascending aorta during cannulation and cross-clamping can predispose to embolization and stroke risk. Recognition of these detrimental effects of on-pump CABG resulted in resurgence of off-pump CABG nearly two decades ago.Off-pump CABG since its resurgence has been a subject of intensive scrutiny and speculation. Despite numerous retrospective nonrandomized studies, prospective randomized trials, and meta-analyses validating the safety and efficacy of off-pump CABG, opponents of the technique have persistently demanded abandonment of off-pump CABG. Several misconceptions and misperceptions are used as an excuse for such demands. This review article examines published scientific evidence to evaluate these misperceptions and misconceptions about off-pump CABG.

Clinical application of individualized total arterial coronary artery bypass grafting in coronary artery surgery

BACKGROUND Total arterial revascularization is associated with increased patency and long-term efficacy and decreased perioperative morbidity and mortality and incidence of cardiac-related events and sternal wound infection compared with conventional coronary artery bypass surgery(CABG),in which the left internal mammary artery(LIMA)is typically grafted to the left anterior descending artery with additional saphenous vein grafts often used.This study determined whether these favorable clinical results could be realized at the authors’institute.AIM To summarize the early efficacy and clinical experience of individualized total arterial coronary artery bypass grafting surgery.METHODS CABG was performed on 35 patients with non-single-vessel coronary artery disease by adopting total arterial grafts at Fourth Affiliated Hospital of Harbin Medical University between April 2016 and December 2019.LIMA was used in 35 patients,radial artery(RA)was used in 35 patients,and right gastroepiploic artery(RGEA)was used in 9 patients.Perioperative complications were observed,short-term graft patency rate was followed-up,and quality of life was assessed.RESULTS All patients underwent off-pump coronary artery bypass and the surgeries were successful.All of them were discharged without any complications or deaths.During the follow-up,it was found that patients’angina symptoms were relieved and New York Heart Association classification for cardiac function was class I to class II.A total of 90 vessels were grafted with no occlusion for internal mammary artery,three occlusions for RA,and one occlusion for RGEA.CONCLUSION The individualized total arterial strategy based on the vessels targeting individual anatomic characteristics can achieve complete revascularization with satisfactory short-term grafting patency rate.

Incidence of Atrial Fibrillation after Off-pump versus On-pump Coronary Artery Bypass Grafting:A Meta-analysis of Randomized Clinical Trials and Propensity Score Matching Trials

The association between atrial fibrillation（AF） after coronary artery bypass grafting（CABG） and the surgical techniques selected has been extensively reported. However, no consistent results were obtained. In the present study, a meta-analysis was conducted by searching the electronic databases Pub Med, Embase, Web of Science, and Cochrane to identify the association of post-CABG AF with on-pump（conventional CABG, c CABG） or off-pump CABG（OPCABG）. Outcomes from randomized clinical trials（RCTs） and propensity score matching（PSM） trials were pooled by using the fixed-effect or the random-effect modeling method, and verified by the quality-effect modeling method. There were 35 studies with 36 independent reports that met the inclusion criteria and were eventually included in our meta-analysis. The total odds ratio（OR） of the incidence of post-CABG AF between OPCABG and c CABG was 0.80（95% CI 0.71–0.91）. The 25 randomized clinical trials（RCTs） had an OR of 0.69（95% CI 0.56–0.86）, while the OR of the 11 PSM trials was 0.88（95% CI 0.77–1.00）. Twenty-six studies involving the patients at a mean age no more than 65 years showed an OR of 0.76（95% CI 0.64–0.90）, whereas 10 studies with patients greater than 65 years old showed an OR of 0.90（95% CI 0.78–1.05）. The results of this meta-analysis suggest that OPCAB surgery may reduce the incidence of post-CABG AF when compared to c CABG and that younger patients may benefit more from OPCAB and have a lower incidence of post-CABG AF.

Physiology of in-situ arterial revascularization in coronary artery bypass grafting: Preoperative,intraoperative and postoperative factors and influences

Surgical revascularization with coronary artery bypass grafting(CABG) has become established as the most effective interventional therapy for patients with moderately severe and severe stable ischemic heart disease(SIHD). This recommendation is based on traditional 5-year outcomes of mortality and avoidance of myocardial infarction leading to reintervention and/or cardiac death. However, these results are confounded in that they challenge the traditional CABG surgical tenets of completeness of anatomic revascularization, the impact of arterial revascularization on late survival, and the lesser impact of secondary prevention following CABG on late outcomes. Moreover, the emergence of physiologic-based revascularization with percutaneous cardiovascular intervention as an alternative strategy for revascularization in SIHD raises the question of whether there are similar physiologic effects in CABG. Finally, the ongoing ISCHEMIA trial is specifically addressing the importance of the physiology of moderate or severe ischemia in optimizing therapeutic interventions in SIHD. So it is time to address the role that physiology plays in surgical revascularization. The long-standing anatomic framework for surgical revascularization is no longer sufficient to explain the mechanisms for short-term and long-term outcomes in CABG. Novel intraoperative imaging technologies have generated important new data on the physiologic blood flow and myocardial perfusion responses to revascularization on an individual graft and global basis. Long-standing assumptions about technical issues such as competitive flow are brought into question by real-time visualization of the physiology of revascularization. Our underestimation of the impact of Guideline Directed Medical Therapy, or Optimal Medical Therapy, on the physiology of preoperative SIHD, and the full impact of secondary prevention on post-intervention SIHD, must be better understood. In this review, these issues are addressed through the perspective of multi-arterial revascularization in CABG, which is emerging(after 30 years) as the "standard of care" for CABG. In fact, it is the physiology of these arterial grafts that is the mechanism for their impact on long-term outcomes in CABG. Moreover, a better understanding of all of these preoperative, intraoperative and postoperative components of the physiology of revascularization that will generate the next, more granular body of knowledge about CABG, and enable surgeons to design and execute a better surgical revascularization procedure for patients in the future.

Comparative study of graft flow between on-pump and off-pump coronary bypass surgery for patients with multivessel coronary artery disease

Objective： To Comparatively study grafts flow between on-pump and off-pump coronary bypass surgery for patients with triple coronary artery disease. Methods ： The grafts flow was studied in 100 patients of OPCAB and compared with 100 cases of CCABG by means of Medi-Stim Butterfly Flowmeter measurement intraoperatively. Results： The mean number of the distal anastomosis was 3.78＋ 1.11 in CCABG group, and 3.83 ＋ 0.93 in OPCAB group. The index of completeness of revascularization in CCABG group was 1.01 ＋ 0.08, and 1.10＋ 0.09 in OPCAB group. The flow of grafts was satisfied in all patients. The PI values were all under 5. There was no significant difference in the mean graft flow and PI value between two groups. Conclusion： OPCAB can provide the same grafts flow and similar completeness of revascularization when compared with CCABG which indicates the similar anastomosis quality of grafts in OPCAB and CCABG groups.

Anesthetic considerations for the patients with off-pump coronary artery bypass grafting

New surgical techniques for coronary artery bypass graft （CABG） have been explored in order to minimize disfiguring scars, avoid cardiopulmonary bypass and decrease hospital residence and costs etc. Improved surgical expense can perform the procedures in some high-risk patients such as poor left ventricular function, redo CABG, advanced age and renal dysfunction etc. Intraoperatively there is an obligatory period of myocardial ischemia, which may lead to significant hemodynamic consequences. It is a quite challenge to anesthetist in managing the intraoperative patient.

Experience with Miniaturized Cardiopulmonary Bypass in Cardiac Surgery: A Prospective Comparison of the NovoSCI Ready System to Off-Pump and Conventional Coronary Artery Bypass Grafting

The major source of morbidity following cardiopulmonary bypass (CPB) is the systemic inflammatory response (SIRS response) which leads to multiple derangements in different organ systems. To combat this, miniaturized cardiopulmonary bypass circuits (MCPBC) have been created to lessen the inflammatory response to CPB. Here we examine early outcomes following coronary artery bypass grafting (CABG) using a MCPBC system compared to conventional bypass techniques at a single institution. Methods: 60 consecutive patients undergoing elective CABG were prospectively enrolled. Nine patients underwent coronary artery bypass grafting (CABG) with conventional CPB (cCABG), 33 underwent off-pump CABG (OPCAB), and the remaining 18 patients underwent CABG with a MCPBC system. Demographics and outcomes were compared between groups and statistical analyses applied. Results: No significant difference was observed in mortality between groups, with only one death reported in total. Morbidity was also low, totaling only 6.7%, with none occurring in the MCPBC group. The MCPBC group required less PRBC and total blood product transfusion than the cCABG and OPCABG groups (p = 0.05), but changes in PLT and Hct over time were not different between groups. Conclusions: The MCPBC system was shown to be comparable to conventional bypass and OPCABG in terms of postoperative complications and mortality. Furthermore, the MCPBC system had the advantage of a decreased transfusion requirement. Based on our preliminary observations, this mini-cardiopulmonary bypass circuit provides a safe alternative to conventional bypass techniques.

Association of Atrial Fibrillation and Amino-terminal Pro-brain Natriuretic Peptide Concentrations in Patients After Off-Pump Coronary Artery Bypass Grafting

Objectives To investigate the possible role of amino-terminal pro-brain natriuretic peptide （NT-proBNP） in the occurrence of atrial fibrillation （AF） after coronary artery bypass grafting （CABG）. Methods This study group included 70 consecutive patients scheduled for elective off-pump CABG. The patients with ejection fraction （EF） less than 0. 30, history of AF, use of class Ⅰ or Ⅲ antiarrhythmic drug, implanted pacemaker, postoperative myocardial infarction or chest reopening for pericardial tamponade were excluded. Preoperative and postoperative serum NT-proBNP levels were measured by radioimmunoassay technique. Results Postoperative AF occurred in 15 patients （21.4%）; these patients had significantly higher median NT-proBNP levels when compared with those without AF after the operation （ P 〈 0. 01 ）. Using multivariate logistic regression analyses, an increase in NT-proBNP level after CABG was found to be independently associated with AF （ OR = 3.78, 95% IC = 1.81 - 4. 89, P 〈 0. 01 ）. Increased age, diabetes mellitus, preoperative use of β-blocker, proximal right coronary artery involvement, and longer operation time were al- so associated with AF. Conclusions These results indicated that AF was associated with higher NT-proBNP concentrations after off pump CABG; the increase in NT-proBNP after CABG may play an important role in the occurrence of AF after the operation. The further studies are needed to define the reason that lead to higher NT-proBNP concentrations among the patients who present AF after off pump CABG.

Off-pump Coronary Endarterectomy and Bypass Grafting in Patients With Diffuse Coronary Artery Disease

Objectives preliminary experience on endarterectomy and To summarize our off-pump coronary bypass grafting in patients with diffuse coronary artery disease. Methods Over a 3year period, 53 patients （41 male） with diffuse coronary artery disease underwent off-pump coronary endarterectomy and bypass grafting at our institution. Patients＇ age ranged from 55 to 79 years. Prior to surgery, 70% of patients were in CCS angina class 2 （n=5） or 3 （n=32）, and nearly half of them （26/53） had history of myocardial infarction. Most patients （n= 50） had triple vessel lesions, with left main stem involvement in 9. Their left ventricular ejection fraction ranged from 26% to 65% （mean 52%）. At the end of operation, a flow-meter was routinely applied to measure the perfusion flow of each postendarterectomy graft. Results In total, 70 endarterectomies were performed in 53 patients, including 38 in left anterior descending artery （LAD）, 8 in circumflex artery and 24 in right coronary artery. Four operations were emergency or urgent in nature. Five patients received on-lay venous patch after endarterectomy in LAD, followed by left internal mammary artery （LIMA） grafting on the patch. The graft conduits included 53 LIMAs and 2 radial arteries, and saphenous veins in others. Mean number of grafts per patient was 3.75. The overall index of complet-eness of revascularization reached 1.03±0.07. There was no death in this group of patients during their post-operative hospital stay （mean duration = 9 days）. Intra-operatively, 63 （90%） out of the 70 grafts after coronary endarterectomy showed satisfactory flow. Two patients had perioperative neither experienced signifi myocardial infarctions but cant hemodynamic deteriations. Conclusions Off-pump coronary endarterectomy with bypass grafting is technically feasible and can be coronary improve zation. performed safely in patients with diffuse artery disease. This strategy may help to the completeness of myocardial revasculariation.