Impact of off-pump coronary artery bypass surgery on systemic inflammation: current best available evidence

Systemic Immune-Inflammation Index Predicts Prolonged Mechanical Ventilation and Intensive Care Unit Stay After off-Pump Coronary Artery Bypass Graft Surgery: A Single-Center Retrospective Study

Purpose

Coronary artery disease (CAD) is the primary cause of mortality in developing countries. Off-pump coronary artery bypass grafting (OPCAB) offers more upside in revascularization by preventing cardiopulmonary bypass trauma and minimizing aortic manipulation. Even though cardiopulmonary bypass is not involved, OPCAB still causes a significant systemic inflammatory response. This study determines the prognostic values of the systemic immune-inflammation index (SII) towards perioperative outcomes in patients who underwent OPCAB surgery.

Patients and methods

This was a single-center retrospective study at the National Cardiovascular Center Harapan Kita, Jakarta, using secondary data from electronic medical records and medical record archives of all patients who underwent OPCAB from January 2019 through December 2021. A total of 418 medical records were obtained, and 47 patients were excluded based on the exclusion criteria. The values of SII were calculated from preoperative laboratory data of segmental neutrophil count, lymphocyte count, and platelet count. Patients were divided into two groups based on the SII cutoff value of 878.056 x 10³/mm³.

Results

The baseline SII values of 371 patients were calculated, among which 63 (17%) patients had preoperative SII values of ≥878.057 x 10³/mm³. High SII values were a significant predictor of prolonged ventilation (RR 1.141, 95% CI 1.001-1.301) and prolonged ICU stay (RR 1.218, 95% CI 1.021-1.452) after OPCAB surgery. A positive correlation was observed between SII and hospital length of stay after OPCAB surgery. From the receiver operating characteristic curve analysis, SII predicted prolonged ventilation duration, with an area under the curve of 0.658 (95% CI 0.575-0.741, p = 0.001).

Conclusion

High preoperative SII values are capable of predicting prolonged mechanical ventilation and intensive care unit stay after OPCAB surgery.

Reduced numbers of regulatory T cells in chronic heart failure seems not to be restored by cardiac resynchronization therapy

BACKGROUND

T cells have been implicated in the development and progression of inflammatory processes in chronic heart failure (CHF). Cardiac resynchronization therapy (CRT) has beneficial effects on symptoms and cardiac remodeling in CHF. However, its impact on the inflammatory immune response remains controversial. We aimed to study the impact of CRT on T cells in heart failure (HF) patients.

METHODS

Thirty-nine HF patients were evaluated before CRT (T0) and six months later (T6). Quantification of T cells, their subsets, and their functional characterization, after in vitro stimulation, were evaluated by flow cytometry.

RESULTS

T regulatory (Treg) cells were decreased in CHF patients (healthy group (HG): 1.08 ± 0.50 versus (heart failure patients (HFP)-T0: 0.69 ± 0.40, P = 0.022) and remaining diminished after CRT (HFP-T6: 0.61 ± 0.29, P = 0.003). Responders (R) to CRT presented a higher frequency of T cytotoxic (Tc) cells producing IL-2 at T0 compared with non-responders (NR) (R: 36.52 ± 12.55 versus NR: 24.71 ± 11.66, P = 0.006). After CRT, HF patients presented a higher percentage of Tc cells expressing TNF-α and IFN-γ (HG: 44.50 ± 16.62 versus R: 61.47 ± 20.54, P = 0.014; and HG: 40.62 ± 15.36 versus R: 52.39 ± 18.66, P = 0.049, respectively).

CONCLUSION

The dynamic of different functional T cell subpopulations is significantly altered in CHF, which results in an exacerbated pro-inflammatory response. Even after CRT, it seems that the inflammatory condition underlying CHF continues to evolve with the progression of the disease. This could be due, at least in part, to the inability to restore Treg cells levels.

TRIAL REGISTRATION

Observational and prospective study with no trial registration.

Microcirculation during surgery

Throughout the long history of surgery, there has been great advancement in the hemodynamic management of surgical patients. Traditionally, hemodynamic management has focused on macrocirculatory monitoring and intervention to maintain appropriate oxygen delivery. However, even after optimization of macro-hemodynamic parameters, microcirculatory dysfunction, which is related to higher postoperative complications, occurs in some patients. Although the clinical significance of microcirculatory dysfunction has been well reported, little is known about interventions to recover microcirculation and prevent microcirculatory dysfunction. This may be at least partly caused by the fact that the feasibility of monitoring tools to evaluate microcirculation is still insufficient for use in routine clinical practice. However, considering recent advancements in these research fields, with more popular use of microcirculation monitoring and more clinical trials, clinicians may better understand and manage microcirculation in surgical patients in the future. In this review, we describe currently available methods for microcirculatory evaluation. The current knowledge on the clinical relevance of microcirculatory alterations has been summarized based on previous studies in various clinical settings. In the latter part, pharmacological and clinical interventions to improve or restore microcirculation are also presented.

Impact of left ventricular inspection employing cardiopulmonary bypass on outcome after implantation of left ventricular assist device

BACKGROUND

Cardiopulmonary bypass (CPB) during left ventricular assist device (LVAD) implantation provides circulatory support and allows for safe inspection of the left ventricle (LV), whereas circulatory support by veno-arterial extracorporeal life support (va-ECLS) or off-pump implantation may reduce postoperative bleeding and inflammatory response.

METHODS

Retrospective analysis of 616 consecutive adult patients who received an LVAD via median sternotomy between January 1, 2015 and December 31, 2019. All patients undergoing concomitant intracardiac procedures other than closure of persistent foramen ovale or atrial septal defect and redo surgeries were excluded from the analysis. The remaining patients (n = 222) were divided into two groups and 1:1 propensity score-matched regarding preoperative parameters: patients who underwent LVAD implantation with LV inspection employing CPB (CPB group, n = 62) and without LV inspection on va-ECLS or off-pump (non-CPB group, n = 62).

RESULTS

The groups were well balanced with regard to preoperative baseline characteristics (standard difference <0.1). Patients in the CPB group required more blood transfusions (median 2 vs. 0 units, p = 0.031) during surgery and in the first 24 h afterwards. The median intensive care unit stay was longer in the CPB group (18 vs. 11 days, p = 0.021). The CPB group showed an absence of perioperative stroke and a smaller number of events per patient-year for postoperative ischemic stroke (0.02 vs. 0.12, p = 0.003). 30-day survival (87% vs. 87.1%) and 1-year survival (80.3% vs. 74%) were similar in both groups (p = 0.78).

CONCLUSION

Visual LV inspection on CPB may reduce the risk of postoperative ischemic stroke. Despite the negative effects of employing CPB in lieu of other intraoperative strategies, survival was similar in both groups.

Do in-hospital outcomes of isolated coronary artery bypass grafting vary between male and female octogenarians?

OBJECTIVES

Female gender and advanced age are regarded as independent risk factors for adverse outcomes after isolated coronary artery bypass grafting (CABG). There is paucity of evidence comparing outcomes of CABG between male and female octogenarians. We aimed to analyse in-hospital outcomes of isolated CABG in this cohort.

METHODS

All octogenarians that underwent isolated CABG, from January 2000 to October 2017, were included. A retrospective analysis of a prospectively collected cardiac surgery database (PATS; Dendrite Clinical Systems, Oxford, UK) was performed. A propensity score was generated for each patient from a multivariable logistic regression model based on 25 pre-treatment covariates. A total of 156 matching pairs were derived.

RESULTS

Five hundred and sixty-seven octogenarians underwent isolated CABG. This included 156 females (mean age 82.1 [SD: 0.9]) and 411 males (mean age 82.4 [SD: 2.1 years]). More males were current smokers (P = 0.002) with renal impairment (P = 0.041), chronic obstructive pulmonary disease (P = 0.048), history of cerebrovascular accident (P = 0.039) and peripheral vascular disease (P = 0.027) while more females had New York Heart Association class 4 (P = 0.02), left ventricular ejection fraction 30-49% (P = 0.038) and left ventricular ejection fraction <30% (P = 0.049). On-pump, CABG was performed in 140 males and 52 females (P = 0.921). There was no difference in in-hospital mortality (5.4% vs 6.4%; P = 0.840), stroke (0.9% vs 1.3%; P = 0.689), need for renal replacement therapy (17.0% vs 13.5%; P = 0.732), pulmonary complications (9.5% vs 8.3%; P = 0.746) and sternal wound infection (2.7% vs 2.6%; P = 0.882). The outcomes were comparable for the propensity-matched cohorts.

CONCLUSIONS

No gender difference in outcomes was seen in octogenarians undergoing isolated CABG.

Postoperative Neutrophil to Lymphocyte Ratio as an Overall Mortality Midterm Prognostic Factor following OPCAB Procedures

BACKGROUND

Off-pump coronary artery bypass grafting (OPCAB) is believed to limit inflammatory reaction. Neutrophil to lymphocyte ratio (NLR) is one of the more common and easily accessible markers of inflammatory response. The aim of the study was to compare postoperative results of NLR with mid-term OPCAB results.

METHODS

In total, 224 patients (198 (88%) men and 26 (12%) women) with mean age 65 +/- 9 years who underwent OPCAB though median full sternotomy in our department in 2018 enrolled into the study. We scrupulously collected the postoperative mid-term results, including survival rate, clinical status and risk for major adverse events, and compared them with perioperative laboratory results.

RESULTS

A three-year follow-up was completed by 198 individuals (90% survival rate) with 12 (5%) showing major adverse cardiovascular (MACE) events risk. In the multivariable analysis, the laboratory parameters noticed on the 1st postoperative day were statistically significantly predictive of survival, including neutrophils (HR 1.59, 1.33-1.89 95%CI, p < 0.0001), platelets (HR 1.01, 1.01-1.01 95%CI, p = 0.0065), NLR (HR 1.47, 1.3-1.65 95%CI, p < 0.0001) and postoperative ejection fraction (HR 0.9, 0.87-0.95 95%CI, p < 0.0001).

CONCLUSIONS

Postoperative NLR above 4.6, as an inflammatory reaction marker, is related to mid-term mortality in OPCAB patients.

Nutritional supplement drink reduces inflammation and postoperative depression in patients after off-pump coronary artery bypass surgery

BACKGROUND

Coronary artery bypass grafting is a surgical treatment for ischemic heart disease. Although development in surgical technique and improvement of perioperative management reduced the postoperative complications, some patients still delayed in progress of postoperative rehabilitation. In this study, we aimed to investigate the effect of daily intake of an herbal medicine-containing drink for rehabilitation after surgery in patients with ischemic heart disease.

AIM

To investigate the effect of taking an herbal medicine-containing, commercially available drink for postoperative rehabilitation in those patients.

METHODS

Patients who underwent isolated off-pump coronary artery bypass (OPCAB) surgery were divided into two groups depend on the timing of the admission to the hospital: the Yunker (YKR) group, that consumed one bottle of a caffeine-free nutritional supplement drink on a daily basis and the control group (CTL) that underwent regular rehabilitation.

RESULTS

A total of 229 patients (CTL = 130, YKR = 99) were enrolled. No significant differences were observed in the baseline characteristics between the two groups. The YKR group had a significantly increased number of daily steps postoperatively (P < 0.05) and had significantly lower postoperative serum tumor necrosis factor-alpha levels (P < 0.01), while no significant differences were observed in the levels of other inflammatory or stress-related cytokines (interleukin-6, adiponectin, superoxide dismutase, and urine 8-hydroxy-2′-deoxyguanosine) between the two groups. Also, the YKR group showed a significant improvement in the Hospital Anxiety and Depression Score (P < 0.05). Moreover, there were no differences in postoperative complications and the duration of postoperative hospital stay between the two groups.

CONCLUSION

Our results demonstrated that the daily intake of an herbal medicine-containing drink after OPCAB surgery may have beneficial effects on cardiac rehabilitation by reducing inflammation markers and depression.

Oxidative Stress in Patients before and after On-Pump and Off-Pump Coronary Artery Bypass Grafting: Relationship with Syntax Score

Objective

Coronary artery bypass grafting (CABG) represents the significant source of increased oxidative stress (OS). We aimed to follow the OS status parameters (i.e., ischemia-modified albumin (IMA), malondialdehyde (MDA), superoxide anion, prooxidant-antioxidant balance (PAB), total oxidant status (TOS), total antioxidant status (TAS), and superoxide-dismutase (SOD)) change through the predefined study times in two different surgical procedures, i.e., cardiopulmonary bypass (CPB) and off-pump coronary artery bypass grafting (OPCAB). Additionally, we aimed to investigate those OS status parameters in specific study times according to SYNTAX score (SS), an established angiographic score for evaluating the extensity and severity of coronary artery disease. Patients and Methods. A total of 107 patients that were planned to undergo CABG were included (i.e., 47 patients in OPCAB and 60 patients in CPB group). Blood samples were taken at 6 time intervals: before surgery (t1), immediately after intervention (t2), 6 h (t3), 24 h (t4), 48 h (t5), and 96 h after termination of the operation (t6).

Results

IMA levels were higher in CPB than that in OPCAB baseline and rose in CPB group in t2 point. TOS decreased in both study groups, compared to baseline values, but without statistical significance. Superoxide anion and PAB significantly increased in t3-t6 study times, in both groups. MDA significantly increased only in CPB group in t5 and t6 interval. MDA was significantly higher in CPB group compared to OPCAB in t6 study point. CPB patients had significantly lower TAS compared to OPCAB patients at the beginning and in t2 and t3 study points. They also had significantly lower SOD activities compared to OPCAB, baseline, and in several study points. Moreover, TAS, SOD, and TAS/TOS ratio were significantly lower, whereas PAB and TOS/TAS were significantly higher in patients with high SS compared to corresponding groups. SOD activity, IMA, and TAS level were the best predictors of high SS.

Conclusion

CPB patients were in more severe ischemia baseline than OPCAB group and IMA rose in CPB patients immediately after the surgery end, but not later. Also, the antioxidant status was significantly lower, whereas the prooxidant status was significantly higher in patients with high SS compared to corresponding groups. SOD activity, IMA, and TAS level were the best predictors of CAD (as determined with SS), showing that SOD and IMA had very good discriminatory capability towards higher SS status.

Dynamic changes in insulin requirements with post-operative time using bedside artificial pancreas to maintain normoglycemia without hypoglycemia after cardiac surgery

It is difficult to manage postoperative blood glucose levels without hyperglycemia and hypoglycemia in cardiac surgery patients even if continuous intravenous insulin infusion is used. Therefore, the insulin requirements for maintaining normoglycemia may be difficult to evaluate and need to be elucidated. In this single-center retrospective study, 30 adult patients (age 71.5 ± 9.0 years old, men 67%, BMI 22.0 ± 3.1 kg/m², diabetes 33%) who underwent cardiac surgery and used bedside artificial pancreas (STG-55) as a perioperative glycemic control were included. We investigated the insulin and glucose requirements to maintain normoglycemia until the day after surgery. The bedside artificial pancreas achieved intensive glycemic control without hypoglycemia under fasting conditions for 15 h after surgery (mean blood glucose level was 103.3 ± 3.1 mg/dL and percentage of time in range (70-140 mg/dL) was 99.4 ± 2.0%). The total insulin requirement for maintaining normoglycemia differed among surgical procedures, including the use of cardiopulmonary bypass during surgery, while it was not affected by age, body mass index, or the capacity of insulin secretion. Moreover, the mean insulin requirement and the standard deviation of the insulin requirements were variable and high, especially during the first several hours after surgery. Treatment using the bedside artificial pancreas enabled intensive postoperative glycemic control without hypoglycemia. Furthermore, the insulin requirements for maintaining normoglycemia after cardiac surgery vary based on surgical strategies and change dynamically with postoperative time, even in the short term.

Preoperative Evaluation and Anesthetic Management of Patients With Liver Cirrhosis Undergoing Cardiac Surgery

Preoperative evaluation and anesthetic management of patients with liver cirrhosis undergoing cardiac surgery remain a clinical challenge because of its high risk for perioperative complications. This narrative review article summarizes the pathophysiology and anesthetic implication of liver cirrhosis on each organ system. It will help physicians to evaluate surgical candidates, to optimize intraoperative management, and to anticipate complications in liver cirrhosis patients undergoing cardiac surgery. Morbidity typically results from bleeding, sepsis, multisystem organ failure, or hepatic insufficiency. These complications occur as a result of the presence of coagulopathy, poor nutritional status, immune dysfunction, cirrhotic cardiomyopathy, and renal and pulmonary dysfunction that occur with liver cirrhosis. Therefore, liver cirrhosis should not be seen as a single disease, but one that manifests with multiorgan dysfunction. Cardiac surgery in patients with liver cirrhosis increases the risk of perioperative complications, and it presents a particular challenge to the anesthesiologist in that nearly every aspect of normally functioning physiology may be jeopardized in a unique way. Accurately classifying the extent of liver disease, preoperative optimization, and surgical risk communication with the patient are crucial. In addition, all teams involved in the surgery should communicate openly and coordinate in order to ensure optimal care. To reduce perioperative complications, consider using off-pump cardiopulmonary bypass techniques and optimal perfusion modalities to mimic current physiologic conditions.

Conversion during off-pump coronary artery bypass graft surgery: A case-control study

Objectives:

Off pump coronary artery bypass (OPCAB) surgery is carried out as an alternative to conventional coronary artery bypass grafting using cardiopulmonary bypass (CPB). At times ‘conversion’ to CPB may be required to bail out a situation resulting from acute decompensation of the heart. It is reported that such conversion carries significant mortality risk. Since we conduct coronary revascularization by OPCAB technique as the preferred technique, we conducted this study with an aim to identify the markers of adverse outcome during conversion in Indian patients.

Design:

Case control retrospective study.

Setting:

Tertiary referral center.

Participants:

We conducted three thousand two hundred OPAB surgeries in the period between 2013 to16. Ninety patients (3.1%) required conversion to complete the revascularization (Con version group). Twice the number of patients who underwent OPCAB surgery without conver sion were chosen as controls (Control group).

Intervention:

OPCAB surgery

Results:

Mortality in the conversion group was 5.56% in contrast to 0.06% in the controls (P = 0.01). The conversion group had higher left ventricular end diastolic pressure, incidence of endarterectomy, and intra-aortic balloon counter pulsation requirement. Female gender was also predictive of conversion. The total chest drain, duration of ventilation, ICU stay and hospital stay were also higher in the conversion group. Conversion was associated with 9.47 times the odds for mortality.

Conclusion:

Conversion during OPCAB is associated with significantly increased mortality. Female gender, increased left ventricular end diastolic pressure and preoperative requirement of Intra-aortic balloon are markers of increased risk of mortality when converted.

The prognostic impact of the controlling nutritional status (CONUT) score in patients undergoing cardiovascular surgery

BACKGROUND

Various postoperative predictive markers following cardiovascular surgery have been examined for use in the current aging population. The controlling nutritional status (CONUT) score, which is advocated not only as a screening tool for poor nutritional status, but also as an immunonutritional assessment, has started to attract attention in several clinical settings, such as in cancer and heart failure patients. The aim of this study was to evaluate the value of the CONUT score as a postoperative prognostic marker in patients who underwent cardiovascular surgery.

METHODS

A total of 75 patients who underwent elective cardiovascular surgery between January 2015 and October 2017 were retrospectively analyzed. The patients were divided into two groups according to their preoperative CONUT score (i.e., CONUT < 2 or CONUT ≥ 2), and their clinicopathological characteristics, surgical outcomes, and overall survival were compared. The median follow-up period was 23 months (range 0-43 months) after surgery.

RESULTS

The high CONUT group (CONUT ≥ 2), which consisted of 30 (40.0%) patients, had a significantly worse prognosis than the low CONUT group with regard to overall survival (p = 0.0007). On multivariate analyses, the CONUT score was identified as the only independent prognostic factor for overall survival (hazard ratio 1.47 per 1 CONUT score increase, 95% confidence interval 1.05-2.06, p < 0.026).

CONCLUSIONS

The CONUT score is a reliable and independent preoperative predictor of overall survival after cardiovascular surgery.

Ten-year improved survival in patients with multi-vessel coronary disease and poor left ventricular function following surgery: A retrospective cohort study

OBJECTIVE

Patients with multi-vessel coronary artery disease and poor left ventricular (LV) function (ejection fraction [EF] < 30%) requiring revascularization are considered 'high-risk'. Limited long-term survival data exists comparing percutaneous coronary intervention (PCI) with second-generation drug-eluting stents (DES) versus surgery for this cohort of patients.

METHODS

We retrospectively reviewed our data for 321 patients with EF < 30% who underwent multi-vessel revascularization from January 2005 to December 2015 using Cox regression analyses and inverse probability treatment weighted (IPTW) methods. We stratified patients that underwent surgical revascularization into on-pump coronary artery bypass grafting (CABG) and off-pump CABG and analyzed all-cause mortality at 10 years compared to PCI.

RESULTS

214 patients underwent CABG (n [on-pump CABG] = 94; n [off-pump CABG] = 120) and 107 patients had PCI with second generation DES. PCI with DES had higher 10-year mortality compared with on-pump CABG (Hazard ratio [HR] = 1.86, 95% confidence interval [CI] = 1.46-2.42; p < 0.001) and off-pump CABG (HR = 2.32, 95% CI = 1.75-3.15; p < 0.001). This was confirmed in IPTW analyses. When adjusting for both measured and unmeasured factors using instrumental variable analyses, PCI with DES had higher 10-year mortality compared with on-pump CABG (Δ = 13.5, 95% CI = 3.2-24.5; p = 0.012) and off-pump CABG (Δ = 16.1, 95% CI = 5.9-25.8; p < 0.001).

CONCLUSION

Surgical revascularization, preferably off-pump CABG, results in better long-term survival compared with PCI using second generation DES for patients with multi-vessel coronary artery disease and poor left ventricular function. Randomized controlled trials in this patient group should be undertaken.

Effects of milrinone on renal perfusion, filtration and oxygenation in patients with acute heart failure and low cardiac output early after cardiac surgery

PURPOSE

Early postoperative heart failure is common after cardiac surgery, and inotrope treatment may impact renal perfusion and oxygenation. We aimed to study the renal effects of the inodilator milrinone when used for the treatment of heart failure after weaning from cardiopulmonary bypass (CPB).

MATERIAL AND METHODS

In 26 patients undergoing cardiac surgery with CPB, we used renal vein catheterization to prospectively measure renal blood flow (RBF), glomerular filtration rate (GFR), and renal oxygenation. Patients who developed acute heart failure and low cardiac output (cardiac index <2.1 L/min/m²) at 30 min after weaning from CPB (n = 7) were given milrinone, and the remaining patients (n = 19) served as controls. Additional measurements were made at 60 min after CPB.

RESULTS

In patients with acute postoperative heart failure, before receiving milrinone, renal blood flow was lower (-33%, p < .05) while renal oxygen extraction was higher (41%, p < .05) compared to the control group. Milrinone increased cardiac index (21%, p < .001), RBF (36%, p < .01) and renal oxygen delivery (35%, p < .01), with no significant change in GFR and oxygen consumption compared to the control group.

CONCLUSIONS

In patients with acute heart failure after weaning from CPB, the milrinone-induced increase in cardiac output was accompanied by improved renal oxygenation.

TRIAL REGISTRATION

ClinicalTrials.gov; identifier NCT02405195, date of registration; March 27, 2015, and NCT02549066, date of registration; 9 September 2015.

Circulating mediators of remote ischemic preconditioning: search for the missing link between non-lethal ischemia and cardioprotection

Acute myocardial infarction (AMI) is one of the leading causes of mortality and morbidity worldwide. There has been an extensive search for cardioprotective therapies to reduce myocardial ischemia-reperfusion (I/R) injury. Remote ischemic preconditioning (RIPC) is a phenomenon that relies on the body's endogenous protective modalities against I/R injury. In RIPC, non-lethal brief I/R of one organ or tissue confers protection against subsequent lethal I/R injury in an organ remote to the briefly ischemic organ or tissue. Initially it was believed to be limited to direct myocardial protection, however it soon became apparent that RIPC applied to other organs such as kidney, liver, intestine, skeletal muscle can reduce myocardial infarct size. Intriguing discoveries have been made in extending the concept of RIPC to other organs than the heart. Over the years, the underlying mechanisms of RIPC have been widely sought and discussed. The involvement of blood-borne factors as mediators of RIPC has been suggested by a number of research groups. The main purpose of this review article is to summarize the possible circulating mediators of RIPC, and recent studies to establish the clinical efficacy of these mediators in cardioprotection from lethal I/R injury.

Ten-Year Follow-Up of Off-Pump and On-Pump Multivessel Coronary Artery Bypass Grafting: MASS III

It was a randomized trial, and 308 patients undergoing revascularization were randomly assigned: 155 to off-pump coronary artery bypass (OPCAB) and 153 to on-pump coronary artery bypass (ONCAB). End points were freedom from death, myocardial infarction, revascularization, and cerebrovascular accidents. The rates for 10-year, event-free survival for ONCAB versus OPCAB were 69.6% and 64%, (hazard ratio [HR]: 0.88; 95% confidence interval [CI] 0.86-1.02; P = .41), respectively. Adjusted Cox proportional hazard ratio was similar (HR: 0.92; 95% CI 0.61-1.38, P = .68). A difference occurred between the duration of OPCAB and ONCAB, respectively (4.9 ± 1.5 vs 6.6 ± 1.1 h, P < .001). Statistical differences occurred between OPCAB and ONCAB in the length of intensive care unit (ICU) stay (20 ± 2.5 vs 48 ± 10 hours, P < .001), time to extubation (5.5 ± 4.2 vs 10.2 ± 3.5 hours, P < .001), hospital stay (6.7 ± 1.4 vs 9.2 ± 1.3 days, P < .001), higher incidence of atrial fibrillation (AF; 33 vs 5 patients, P < .001), and blood requirements (46 vs 64 patients, P < .001). Grafts per patient was higher in ONCAB (3.15 vs 2.55 grafts, P < .001). No difference existed between the groups in primary composite end points at 10-year follow-up. Although OPCAB surgery was related to a lower number of grafts and higher incidence of AF, it had no effects related to long-term outcomes.

Vitamin C to Improve Organ Dysfunction in Cardiac Surgery Patients-Review and Pragmatic Approach

The pleiotropic biochemical and antioxidant functions of vitamin C have sparked recent interest in its application in intensive care. Vitamin C protects important organ systems (cardiovascular, neurologic and renal systems) during inflammation and oxidative stress. It also influences coagulation and inflammation; its application might prevent organ damage. The current evidence of vitamin C's effect on pathophysiological reactions during various acute stress events (such as sepsis, shock, trauma, burn and ischemia-reperfusion injury) questions whether the application of vitamin C might be especially beneficial for cardiac surgery patients who are routinely exposed to ischemia/reperfusion and subsequent inflammation, systematically affecting different organ systems. This review covers current knowledge about the role of vitamin C in cardiac surgery patients with focus on its influence on organ dysfunctions. The relationships between vitamin C and clinical health outcomes are reviewed with special emphasis on its application in cardiac surgery. Additionally, this review pragmatically discusses evidence on the administration of vitamin C in every day clinical practice, tackling the issues of safety, monitoring, dosage, and appropriate application strategy.

Coronary artery bypass grafting in patients with severe chronic kidney disease: a propensity score-weighted analysis on the impact of on-pump versus off-pump strategies

OBJECTIVES

The optimal surgical strategy regarding the use of cardiopulmonary bypass during coronary artery bypass grafting in patients with severe chronic kidney disease remains controversial.

METHODS

Between 1997 and 2015, we identified 321 consecutive patients with severe chronic kidney disease (Stage 4 or 5) based on the National Kidney Foundation Classification (estimated glomerular filtration rate <30 ml/min/1.73 m2). Of these, on-pump and off-pump coronary artery bypass grafting were performed in 118 and 203 patients, respectively. Surgical outcomes between the 2 groups were analysed after adjustment with propensity scores based on 30 baseline covariates.

RESULTS

Early mortality occurred in 11 (9.3%) and 2 (1.0%) patients in the on- and off-pump groups, respectively (P = 0.001). The off-pump group had fewer distal anastomoses than the on-pump group (3.1 ± 0.9 vs 2.8 ± 1.0; P = 0.003). After adjustment, the off-pump group showed a significantly lower risk of early death (P = 0.002), sternal wound infection (P = 0.002) and prolonged ventilation (>24 h) (P < 0.001). During the study period, 186 patients died, and the off-pump strategy was associated with a reduced risk of overall mortality (hazard ratio 0.61, 95% confidence interval 0.46-0.81; P < 0.001). On landmark analysis, however, cardiopulmonary bypass use was found to be unassociated with an increased risk of mortality after 1 year (P = 0.198).

CONCLUSIONS

The on-pump strategy for patients with severe chronic kidney disease was associated with a significantly higher risk of mortality and morbidities, which is particularly attributable to a greater risk of cardiopulmonary bypass use in the early postoperative period. The study result suggests that the off-pump strategy might be beneficial in performing coronary artery bypass grafting, despite potentially incomplete revascularization in this high-risk cohort.

Current Evidence about Nutrition Support in Cardiac Surgery Patients-What Do We Know?

Nutrition support is increasingly recognized as a clinically relevant aspect of the intensive care treatment of cardiac surgery patients. However, evidence from adequate large-scale studies evaluating its clinical significance for patients&rsquo; mid- to long-term outcome remains sparse. Considering nutrition support as a key component in the perioperative treatment of these critically ill patients led us to review and discuss our understanding of the metabolic response to the inflammatory burst induced by cardiac surgery. In addition, we discuss how to identify patients who may benefit from nutrition therapy, when to start nutritional interventions, present evidence about the use of enteral and parenteral nutrition and the potential role of pharmaconutrition in cardiac surgery patients. Although the clinical setting of cardiac surgery provides advantages due to its scheduled insult and predictable inflammatory response, researchers and clinicians face lack of evidence and several limitations in the clinical routine, which are critically considered and discussed in this paper.

Vascular Endothelial Dysfunction during Cardiac Surgery: On-Pump versus Off-Pump Coronary Surgery

BACKGROUND

Cardiac surgery often causes ischemia and development of a systemic inflammatory response syndrome, which impairs vascular barrier function, normally maintained by the endothelial cell line and the endothelial glycocalyx (EG). The EG normally covers and protects healthy endothelial cells throughout the vasculature. The aim of the present study was to assess the disruption of the cellular part of the microvascular barrier by determining parameters of endothelial cell activation known to influence and reflect cell-cell junctional integrity. Particular attention was placed on angiopoietins and their important effects on endothelial gap junctions. Furthermore, comparative measurements were undertaken in patients undergoing on- and off-pump cardiac surgery, the latter group presumably experiencing less ischemic stress.

METHODS

30 patients undergoing elective coronary artery bypass surgery were assigned to the conventional coronary artery bypass (CCAB) group (n = 15) or the off-pump coronary artery bypass grafting (OPCAB) group (n = 15). Blood samples were obtained for measuring angiopoietin-1 (Ang-1), angiopoietin-2 (Ang-2), vascular endothelial (VE)-cadherin, and endocan at various time points.

RESULTS

There were significant increases in all measured parameters in both study groups versus the respective basal values. Maximal increases were as follows: Ang-1: CCAB +220%, OPCAB +166%, p < 0.05 each; Ang-2: CCAB +150%, OPCAB +20%, p < 0.05 each; VE-cadherin: CCAB +87%, OPCAB +66%, p < 0.05 each; endocan: CCAB +323%, OPCAB +72%, p < 0.05 each.

CONCLUSION

The present study demonstrates the activation of endothelial cells, shedding of cell-cell contacts and a potential intrinsic counterregulation by Ang-1 and endocan in patients undergoing major cardiac surgery. Quantitatively greater deviations of parameters in the CCAB than in the OPCAB group suggest a relation between the occurrence of ischemia/reperfusion and the extent of endothelial activation.

Shed-blood-separation and cell-saver: an integral Part of MiECC? Shed-blood-separation and its influence on the perioperative inflammatory response during coronary revascularization with minimal invasive extracorporeal circulation systems – a randomized controlled trial

Objective:

The postoperative systemic inflammatory response after cardiopulmonary bypass (CPB) is still an undesirable side-effect after cardiac surgery. It is most likely caused by blood contact with foreign surfaces and by the surgical trauma itself. However, the recirculation of activated shed mediastinal blood is another main cause of blood cell activation and cytokine release. Minimal invasive extracorporeal circulation (MiECC) comprises a completely closed circuit, coated surfaces and the separation of suction blood. We hypothesized that MiECC, with separated cell saved blood, would induce less of a systemic inflammatory response than MiECC with no cell-saver. The aim of this study was, therefore, to investigate the impact of cell washing shed blood from the operating field versus direct return to the ECC on the biomarkers for systemic inflammation.

Material and methods:

In the study, patients with MiECC and cell-saver were compared with the control group, patients with MiECC and direct re-transfusion of the drawn blood shed from the surgical field.

Results:

High amounts of TNF-α (+ 120% compared to serum blood) were found in the shed blood itself, but a significant reduction was demonstrated with the use of a cell-saver (TNF-α ng/l post-ECC 10 min: 9.5±3.5 vs. 19.7±14.5, p<0.0001). The values for procalcitonin were not significantly increased in the control group (6h: 1.07±3.4 vs. 2.15±9.55, p=0.19) and lower for C-reactive protein (CRP) (24h: 147.1±64.0 vs.134.4±52.4 p=0.28).

Conclusion:

The use of a cell-saver and the processing of shed blood as an integral part of MiECC significantly reduces the systemic cytokine load. We, therefore, recommend the integration of cell-saving devices in MiECC to reduce the perioperative inflammatory response.

A Thrombomodulin Gene Polymorphism (C1418T) Is Associated with Early Outcomes in Patients Undergoing Coronary Artery Bypass Graft Surgery with a Conventional Cardiopulmonary Bypass during Hospitalization

Background: Thrombomodulin (TM) is a type of cell membrane-bound anticoagulant protein cofactor in the thrombin-mediated activation of protein C. Previous evidence has shown an association between TM polymorphisms and systemic inflammation. Conventional cardiopulmonary bypass (CPB), beating-heart CPB, and off-pump techniques have been widely used in cardiac surgery. However, these techniques may also cause systemic inflammatory responses in the patients. Whether TM polymorphisms are associated with systemic inflammation after cardiac surgery is still unclear. Methods: We analyzed the TM gene C1418T polymorphisms in 347 patients who underwent coronary artery bridge graft (CABG) surgery using allele-specific primers in a PCR assay. The clinical data during the hospital stay were collected and tested for correlations with the TM gene C1418T polymorphisms. Results: We separated the patients into two groups based on their TM C1418T genotype (CC genotype group and CT/TT genotype group). The days spent in an intensive care unit (ICU) and the incidence of fever in the ICU were significantly lower in the beating-heart CPB and off-pump groups than in the conventional CPB group. Additionally, the TM gene C1418T polymorphisms did not affect the early outcomes in patients in the beating-heart CPB and off-pump groups. Interestingly, in the conventional CPB group, patients with the CC genotype had a lower rate of fever, shorter duration of fever, and delay of ICU when compared with the CT/TT genotype. Conclusion: Surgeons may use a patient’s TM gene C1418T polymorphism to predict the strength of systemic inflammation and speculate on early outcomes during hospitalization before conventional CPB is performed.

Minimally Invasive Aortic Valve Replacement via Right Anterior Minithoracotomy and Central Aortic Cannulation

Objective

This study reports the evolution of a minimally invasive aortic valve replacement (mini-AVR) technique that uses a right anterior minithoracotomy approach with central cannulation, for a 13-year period. This technique has become our standard approach for isolated primary AVR in nearly all patients.

Methods

This observational study evaluated perioperative clinical outcomes of patients 18 years or older who underwent mini-AVR from November 2003 to June 2015.

Results

The mini-AVR technique was used in 202 patients during two periods of 2003 to 2009 (n = 65, “early”) and 2010 to 2015 (n = 137, “late”). The mean ± SD age was 72.5 ± 12.9 years and 60% were male. Demographic parameters were statistically similar between the study periods, except for increased body weight in the later period (75.3 ± 14.7 vs 80.9 ± 20.8 kg, P = 0.03). The mean cardiopulmonary bypass and aortic cross-clamp times were significantly different by each year and Bonferroni adjustment, with significant decreases in cardiopulmonary bypass and aortic cross-clamp times beginning 2006. Compared with the early study period, late study period patients were more often extubated intraoperatively (52% vs 12%, P < 0.001), had less frequent prolonged ventilator use postoperatively (6% vs 16%, P = 0.018), required fewer blood transfusions (mean, 2.0 ± 2.3 U vs 3.6 ± 3.0 U; P = 0.011), and had shorter postoperative stay (6.3 ± 4.5 days vs 8.0 ± 5.9 days, P = 0.026). Numerically, fewer postoperative strokes (1% vs 6%, P = 0.09) and fewer reoperations for bleeding (3% vs 6%, P = 0.3) occurred in the late period. In-hospital mortality did not differ (1/65 early vs 3/137 late).

Conclusions

Overall mini-AVR intraoperative and postoperative clinical outcomes improved for this 13-year experience.

Neurologic complications of cardiac and vascular surgery

This chapter will provide an overview of the major neurologic complications of common cardiac and vascular surgeries, such as coronary artery bypass grafting and carotid endarterectomy. Neurologic complications after cardiac and vascular surgeries can cause significant morbidity and mortality, which can negate the beneficial effects of the intervention. Some of the complications to be discussed include ischemic and hemorrhagic stroke, seizures, delirium, cognitive dysfunction, cerebral hyperperfusion syndrome, cranial nerve injuries, and peripheral neuropathies. The severity of these complications can range from mild to lethal. The etiology of complications can include a variety of mechanisms, which can differ based on the type of cardiac or vascular surgery that is performed. Our knowledge about neuropathology, prevention, and management of surgical complications is growing and will be discussed in this chapter. It is imperative for clinicians to be familiar with these complications in order to narrow the differential diagnosis, start early management, anticipate the natural history, and improve outcomes.

Two decades of off-pump coronary artery bypass surgery: Harefield experience

The morbidity and mortality associated with conventional coronary artery bypass grafting (CABG) attributed to invasiveness of cardiopulmonary bypass (CPB) has been well documented. Recognition of this invasiveness with a focus centered on abolishing, or at least reducing the CPB associated morbidity and mortality led to the resurgence of off-pump coronary artery bypass (OPCAB) surgery nearly two decades ago. At about the same time, OPCAB was adopted at Harefield hospital partly as an institutional drive to promote innovation and partly as a strategy to improve outcomes. What was deemed as a challenging technique initially and practiced by a single surgeon has now become a valid substitute to conventional CABG for achieving complete myocardial revascularization. This strategy now accounts for more than 50% of all coronary artery surgery operations at Harefield hospital and is systematically used to treat all coronary anatomies; achieve complete revascularization by accessing all territories subtended by main coronary arteries; and accomplish equivalent quality grafts without restriction in vascular conduit usage. This review article provides an overview of the evolution of OPCAB surgery at an institution with a well-established OPCAB program confirming that as surgeons' experience matures, OPCAB surgery permits safe and effective total myocardial revascularization in virtually all patients with multivessel coronary artery disease.

Preoperative values of inflammatory markers predict clinical outcomes in patients after CABG, regardless of the use of cardiopulmonary bypass

Objective

The impact of systemic inflammation on clinical outcomes after CABG surgery is still controversial. In this study, we evaluated the impact of the markers of inflammation, endothelial damage and platelet activation on clinical outcomes after on- and off-pump CABG.

Methods

A group of 191 consecutive on- and off-pump CABG patients were prospectively studied. Blood samples were drawn before surgery, 18–36 h after the procedure and 5–7 days postoperatively and analyzed for 8-iso-prostaglandin F_2α (8-iso-PGF_2α), asymmetric dimethylarginine (ADMA) and β-thromboglobulin (β-TG). White blood count and C-reactive protein were measured twice, first before and then during the first 18–36 h after CABG. The primary clinical end-points were: low cardiac output syndrome (LCOS), postoperative myocardial infarction (PMI) and in-hospital cardiovascular death.

Results

Elevation of 8-iso-PGF_2α, ADMA and β-TG before surgery was associated with an increased risk of morbidity and mortality after CABG. There were no differences in analyzed markers and clinical outcomes between the on- and off-pump groups. Even during the uncomplicated postoperative course the inflammatory response was enhanced and still remained higher than baseline 5–7 days after surgery.

Conclusion

Links between preoperative 8-iso-PGF_2α, ADMA and β-TG and unfavorable early post-CABG outcomes suggest that these markers could be useful in identifying patients with increased risk of LCOS, PMI and in-hospital cardiovascular death following elective CABG.

Effect of preoperative statin therapy on early postoperative memory impairment after off-pump coronary artery bypass surgery

Context:

Frequent incidence of early postoperative memory impairment (POMI) after cardiac surgery remains a concern because of associated morbidity, impaired quality of life, and increased health care cost.

Aim:

To assess the effect of preoperative statin therapy on POMI in patients undergoing off-pump coronary artery bypass (OPCAB) surgery.

Setting and Design:

Prospective observational study in a tertiary level hospital.

Methods:

Sixty patients aged 45–65 years undergoing OPCAB surgery were allocated into two groups of 30 each. Group A patients were receiving statin and Group B patients were not receiving statins. All patients underwent memory function assessment preoperatively after admission to hospital and on the 6^th postoperative day using postgraduate institute memory scale.

Statistical Analysis:

Appropriate tests were applied with SPSS 20 to compare both groups. The value P < 0.05 was considered statistically significant. Multiple regression analysis was performed with confounding factors to determine the effect on memory impairment.

Results:

Patients in Group A showed significant postoperative deterioration in 6 of the 10 functions and in Group B showed deterioration in 9 of 10 functions tested compared to preoperative scores. Intergroup comparison detected less POMI in Group A compared to Group B and was statistically significant in 8 memory functions. Multiple regression analysis detected statin as an independent factor in preventing memory impairment.

Conclusions:

Preoperative statin therapy attenuates the early POMI in patients undergoing OPCAB. Future long-term studies will define the efficacy of statin on POMI.

Similarity of coagulation and inflammation despite different surgical revascularization strategies – a prospective randomized trial

Background:

Supposedly, minimized extracorporeal circulation or off-pump revascularization as alternatives to conventional extracorporeal circulation (ONCAB) reduce inflammation and coagulation disturbances.

Methods:

One hundred and twenty coronary artery bypass graft (CABG) patients were prospectively randomized for three surgical techniques. Coagulation and inflammation markers were measured up to 72 hours postoperatively.

Results:

Coagulation factors I, II, V, X, antithrombin III and C-reactive protein did not differ perioperatively between the groups and increased, as did several other markers, 12 to 72 hours postoperatively. Compared to its alternatives, ONCAB showed the most obvious transient increase in thrombin-antithrombin complexes (p<0.0001), D-dimers (p=0.0059), tissue factor pathway inhibitor (p=0.0005), factor VIII (p=0.0041) and tumor necrosis factor α (p=0.0300) during the operation and up to 12 hours postoperatively. Furthermore, ONCAB generated lower leukocyte and platelet counts and higher values of soluble P-selectin and soluble intercellular adhesion molecule 1 at some time points.

Conclusions:

With similarity in pivot coagulation factors, a specific detrimental influence of ONCAB on common coagulation pathways was excluded. Higher perioperative concentrations of products from the coagulation cascade most likely indicate activation of pericardial blood – recirculated only in ONCAB. Furthermore, with only temporary differences in markers of inflammation, the alternatives to ONCAB altogether were without advantage at 72 hours postoperatively. In the general answer to surgical trauma, the part of modern extracorporeal circulation is possibly overestimated. The study is registered at the German Clinical Trial Registry. Registration number DRKS00007580. URL: https://drks-neu.uniklinik-freiburg.de/drks_web/ URL: http://apps.who.int/trialsearch/

[Cognitive dysfunction after coronary artery bypass grafting]

Despite the advances in surgical and anesthetic techniques for coronary artery bypass grafting (CABG), the incidence of neurological complications, including postoperative cognitive dysfunction (POCD), remains high. CABG is performed more often in elderly patients with severe comorbidities. However, comprehensive prevention measures and POCD rehabilitation have not yet been developed. Physical training is an effective and safe method for correcting endothelial dysfunction, severe systemic inflammatory response syndrome, lipid peroxidation, i.e. mechanisms contributing to the development and severity of POCD.

Comparison of neutrophil:lymphocyte ratios following coronary artery bypass surgery with or without cardiopulmonary bypass

Objective

Coronary artery bypass graft (CABG) surgery may induce postoperative systemic changes in leukocyte counts, including leukocytosis, neutrophilia or lymphopenia. This retrospective clinical study investigated whether offpump coronary artery bypass (OPCAB) surgery working on the beating heart without extracorporeal circulation could favourably affect leukocyte counts, including neutrophil-tolymphocyte (N:L) ratio, after CABG.

Methods

In this study, 30 patients who underwent isolated CABG with cardiopulmonary bypass (CPB), and another 30 patients who underwent the same operation without CPB between May 2010 and May 2013, were screened from the computerised database of our hospital. Pre-operative, and first and fifth postoperative day differential counts of leukocytes with the N:L ratio of peripheral blood were obtained.

Results

A significant increase in total leukocyte and neutrophil counts and N:L ratio, and a decrease in lymphocyte counts were observed at all time points after surgery in both groups. N:L ratio was significantly higher in the CPB group compared with the OPCAB group on the first postoperative day (20.73 ± 13.85 vs 10.19 ± 4.55, p < 0.001), but this difference disappeared on the fifth postoperative day.

Conclusion

CPB results in transient but significant changes in leukocyte counts in the peripheral blood stream in terms of N:L ratio compared with the off-pump technique of CABG.

Evaluation of systemic inflammatory response in cardiovascular surgery via interleukin-6, interleukin-8, and neopterin

AIM

The aim of this study was to evaluate the serum levels of interleukin-6 (IL-6), IL-8, and neopterin as a sign of systemic inflammatory response syndrome after open-heart surgery. In this study, we evaluated the influences on the levels of IL-6, IL-8, and neopterin of coronary artery bypass grafting (CABG) and valve replacement surgeries with and without the use of extracorporeal circulation (ECC).

MATERIALS AND METHODS

This prospective study was performed in 30 patients. In this study, we evaluated patients who underwent valve replacement surgery (group 1, n = 10), CABG with ECC (group 2, n = 10), or CABG using the beating-heart technique (group 3, n = 10). With the Human Investigation Ethics Committee consent, blood samples were obtained from the patients before the surgery (T0) and after 1 hour (T1), 4 hours (T2), 24 hours (T3), and 48 hours (T4) of protamine injection. IL-6, IL-8, and neopterin levels were measured using commercial enzyme-linked immunosorbent assay kits.

RESULTS

The demographic data and preoperative and operative characteristics of the patients were similar. Neopterin IL-6 and IL-8 levels significantly increased first at the fourth hour after the surgery. When compared to the levels before the surgery, this increase was statistically significant. Unlike the other 2 groups of patients, those who experienced CABG with the beating-heart technique (group 3) had decreased neopterin levels at the first hour after the surgery, but this decrease was not statistically significant. Neopterin levels increased later in the OPCAB group, but these increased levels were not as high as the neopterin levels of groups 1 and 2. Neopterin reached maximum levels at the 24th hour and, unlike groups 1 and 2, in group started to decrease at the 48th.

CONCLUSIONS

Complement activation, cytokine production, and related cellular responses are important factors during open-heart surgery. It is certain that ECC activates the complement systems, and activated complement proteins cause the production of several cytokines. In our study, neopterin levels in patients who underwent beating-heart method surgery were lower than those in the other groups, and these levels started to decrease at the 48th hour. These data suggest that the systemic inflammatory response was less activated in that patient group. The beating-heart method might be an important alternative in CABG surgery to minimize the complications and mortality related to surgery.

Long-term follow-up of off-pump and on-pump coronary artery bypass grafting

OBJECTIVE

Despite increasing recognition of the benefits of off-pump coronary artery bypass grafting (CABG), concerns persist regarding its impact on long-term mortality and freedom from reintervention. In this study, we assessed the impact of off-pump CABG on long-term outcomes.

METHODS

From January 2002 to December 2002, a total of 307 consecutive patients who underwent isolated multivessel off-pump CABG at our institution were compared with a control group of 397 patients who underwent multivessel on-pump CABG during the same period. Perioperative data were prospectively collected and compared. In addition, univariate and risk-adjusted comparisons between the two groups were performed at 10 years.

RESULTS

After adjusting for clinical covariates, off-pump CABG did not emerge as a significant independent predictor of long-term mortality [hazard ratio (HR), 0.91; 95% confidence interval (CI), 0.70-1.12], readmission to hospital for cardiac cause (HR, 0.96; 95% CI, 0.78-1.10), or the need for reintervention (HR, 0.93; 95% CI, 0.87-1.05).

CONCLUSIONS

At long-term follow-up, off-pump CABG remains a safe and effective myocardial revascularization strategy with no adverse impact on survival or freedom from reintervention.

Neutrophil gelatinase-associated lipocalin after off pump versus on pump coronary artery surgery

CONTEXT

Cardiac surgery.

OBJECTIVE

To compare plasma and urinary neutrophil gelatinase-associated lipocalin (P-/U-NGAL) in on-pump (n = 43) versus off-pump (n = 40) surgery.

MATERIALS AND METHODS

We obtained perioperative P-/U-NGAL and outcome data.

RESULTS

P-/U-NGAL increased after surgery. P-NGAL was higher post-surgery in on pump patients (139 versus 67 µg L(-1); p < 0.001), but not at 24 h. There were no differences in U-NGAL. Correlation between P-/U-NGAL and plasma creatinine was weak.

DISCUSSION

P-NGAL acts like a neutrophil activation biomarker and U-NGAL like a tubular injury marker.

CONCLUSION

On-pump patients had greater neutrophil activation. On- versus off-pump surgery had similar impact on tubular cells.

Calpain activity and Toll-like receptor 4 expression in platelet regulate haemostatic situation in patients undergoing cardiac surgery and coagulation in mice

Human platelets express Toll-like receptors (TLR) 4. However, the mechanism by which TLR4 directly affects platelet aggregation and blood coagulation remains to be explored. Therefore, in this study, we evaluated the platelet TLR4 expression in patients who underwent CABG surgery; we explored the correlation between platelet TLR4 expression and the early outcomes in hospital of patients. Additionally, C57BL/6 and C57BL/6-Tlr^LPS−/− mice were used to explore the roles of platelet TLR4 in coagulation by platelet aggregometry and rotation thromboelastometry. In conclusion, our results highlight the important roles of TLR4 in blood coagulation and platelet function. Of clinical relevance, we also explored novel roles for platelet TLR4 that are associated with early outcomes in cardiac surgery.

Real-time monitoring of endogenous lipid peroxidation by exhaled ethylene in patients undergoing cardiac surgery

Pulmonary and systemic organ injury produced by oxidative stress including lipid peroxidation is a fundamental tenet of ischemia-reperfusion injury, inflammatory response to cardiac surgery, and cardiopulmonary bypass (CPB) but is not routinely measured in a surgically relevant time frame. To initiate a paradigm shift toward noninvasive and real-time monitoring of endogenous lipid peroxidation, we have explored pulmonary excretion and dynamism of exhaled breath ethylene during cardiac surgery to test the hypothesis that surgical technique and ischemia-reperfusion triggers lipid peroxidation. We have employed laser photoacoustic spectroscopy to measure real-time trace concentrations of ethylene from the patient breath and from the CPB machine. Patients undergoing aortic or mitral valve surgery-requiring CPB (n = 15) or off-pump coronary artery bypass surgery (OPCAB) (n = 7) were studied. Skin and tissue incision by diathermy caused striking (> 30-fold) increases in exhaled ethylene resulting in elevated levels until CPB. Gaseous ethylene in the CPB circuit was raised upon the establishment of CPB (> 10-fold) and decreased over time. Reperfusion of myocardium and lungs did not appear to enhance ethylene levels significantly. During OPCAB surgery, we have observed increased ethylene in 16 of 30 documented reperfusion events associated with coronary and aortic anastomoses. Therefore, novel real-time monitoring of endogenous lipid peroxidation in the intraoperative setting provides unparalleled detail of endogenous and surgery-triggered production of ethylene. Diathermy and unprotected regional myocardial ischemia and reperfusion are the most significant contributors to increased ethylene.

The importance of intraoperative selenium blood levels on organ dysfunction in patients undergoing off-pump cardiac surgery: a randomised controlled trial

INTRODUCTION

Cardiac surgery is accompanied by an increase of oxidative stress, a significantly reduced antioxidant (AOX) capacity, postoperative inflammation, all of which may promote the development of organ dysfunction and an increase in mortality. Selenium is an essential co-factor of various antioxidant enzymes. We hypothesized a less pronounced decrease of circulating selenium levels in patients undergoing off-pump coronary artery bypass (OPCAB) surgery due to less intraoperative oxidative stress.

METHODS

In this prospective randomised, interventional trial, 40 patients scheduled for elective coronary artery bypass grafting were randomly assigned to undergo either on-pump or OPCAB-surgery, if both techniques were feasible for the single patient. Clinical data, myocardial damage assessed by myocard specific creatine kinase isoenzyme (CK-MB), circulating whole blood levels of selenium, oxidative stress assessed by asymmetric dimethylarginine (ADMA) levels, antioxidant capacity determined by glutathionperoxidase (GPx) levels and perioperative inflammation represented by interleukin-6 (IL-6) levels were measured at predefined perioperative time points.

RESULTS

At end of surgery, both groups showed a comparable decrease of circulating selenium concentrations. Likewise, levels of oxidative stress and IL-6 were comparable in both groups. Selenium levels correlated with antioxidant capacity (GPx: r = 0.720; p<0.001) and showed a negative correlation to myocardial damage (CK-MB: r =  -0.571, p<0.001). Low postoperative selenium levels had a high predictive value for the occurrence of any postoperative complication.

CONCLUSIONS

OPCAB surgery is not associated with less oxidative stress and a better preservation of the circulating selenium pool than on-pump surgery. Low postoperative selenium levels are predictive for the development of complications.

TRIAL REGISTRATION

ClinicalTrials.gov NCT01409057.

Aortic valve replacement through J-shaped partial upper sternotomy

The introduction of minimally invasive techniques in general surgery, in the late 1980s, influenced cardiac surgery as well. This led to the emergence of several minimal access approaches for aortic valve replacement (AVR). Currently, the upper partial sternotomy with unilateral J-shaped extension to the right through the fourth intercostal space is the most popular minimal access approach. This approach offers the comfort factor of sternotomy, improved cosmetic result, preserved respiratory mechanics, and last but not the least cost saving as no new equipment is required. On the other hand, inability to visualize the whole heart, adequately de-air the left heart, and failure to apply epicardial pacing wires are some of the perceived disadvantages of this approach. This article provides a comprehensive review of the indications, contraindications, technical aspects, outcomes, advantages and disadvantages of AVR through J-shaped partial upper sternotomy.

Outcomes and predictors of mortality and stroke after on-pump and off-pump coronary artery bypass surgery in octogenarians

OBJECTIVE

Octogenarians, as the fastest growing stratum of the population and with the highest prevalence of coronary artery disease, are being increasingly referred for coronary artery bypass grafting (CABG). The general perception is that the presence of comorbidities and the propensity for neurological injury expose them to a higher risk for mortality and morbidity after conventional on-pump CABG, and therefore, off-pump CABG should be preferentially offered to octogenarians to improve outcomes. This study evaluates the in-hospital outcomes and predictors of mortality and stroke in octogenarians undergoing on- and off-pump CABG at our institution.

METHODS

From January 2000 to December 2010, a total of 290 octogenarians underwent off-pump (n = 217) and on-pump (n = 73) CABG. Their data were prospectively entered into the cardiac surgery database (Patients Analysis & Tracking System; Dendrite Clinical Systems, Ltd, Oxford, England, United Kingdom) and analyzed retrospectively. Outcome measures included in-hospital mortality, major complications, and length of stay. Multivariate analysis was performed to identify predictors of combined outcome of in-hospital mortality and stroke.

RESULTS

The mean ± SD age of the patients was 82 ± 2.0 years. Preoperative demographics were similar for the on-pump and off-pump groups. The patients who underwent off-pump CABG had a lower number of distal anastomoses performed compared with the patients who underwent on-pump CABG [mean difference, 0.2; 95% confidence interval (CI), 0.02-0.4; P = 0.03]. However, the ratio of grafts (received/needed) was the same in both groups. In-hospital mortality for the entire cohort was 7.2%, with no significant difference between the groups for death (6.0% vs 11.0%; P = 0.08), stroke (2.8% vs 2.8%; P = 1.0), other major complications, and length of hospital stay. Independent predictors of combined outcome identified from the multiple logistic model included heart failure [odds ratio (OR), 4.4; 95% CI, 1.5-13.0; P = 0.008], diabetes (OR, 2.6; 95% CI, 1.0-6.0; P = 0.046), nitrate infusion (OR, 2.9; 95% CI, 1.1-8.0; P = 0.04), postoperative renal failure requiring hemofiltration (OR, 8.6; 95% CI, 3.5-21.1; P < 0.001), and postoperative ventricular arrhythmias (OR, 7.3; 95% CI, 1.9-27.8; P = 0.009).

CONCLUSIONS

Both on-pump and off-pump CABG are reasonable revascularization strategies in octogenarians. Careful patient selection and individualized treatment decisions can minimize postoperative mortality and morbidity in octogenarians undergoing on- and off-pump CABG.

A Brief History of Cardiopulmonary Bypass

The development and application of cardiopulmonary bypass (CPB) to permit open heart surgery is considered among the most important clinical advances in medicine during the last half of the 20th century. The birth of CPB for cardiac surgery is attributed to its first successful clinical use by John Gibbon Jr, 51 years ago but its practical clinical use really began in the spring and summer of 1955 when 2 groups led by John Kirklin at the Mayo Clinic and C Walton Lillehei at the University of Minnesota, initiated the routine use of CPB for open heart surgery. However, considerable developments were necessary and preceded the clinical accomplishment of CPB, and much has followed to make it the remarkably safe and effective procedure that it has become today. Many currently practicing cardiac anesthesiologists, cardiac surgeons, and perfusionists are unaware of how brief its history is and how much the practice of CPB has changed during its short existence. The aim of this article is to review this fascinating history and the lessons that can be learned from this review, and to indicate the opportunities that still exist for advancement.