Is postoperative cognitive decline after cardiac surgery associated with plasma beta amyloid 1–42 levels?

Background Postoperative cognitive decline following cardiac surgery is one of the frequently reported complications affecting postoperative outcome, characterized by impairment of memory or concentration. The aetiology is considered multifactorial and the research conducted so far has presented contradictory results. The proposed mechanisms to explain the cognitive decline associated with cardiac surgery include the neurotoxic accumulation of β-amyloid (Aβ) proteins similar to Alzheimer's disease. The comparison of coronary artery bypass grafting procedures concerning postoperative cognitive decline and plasmatic Aβ1-42 concentrations has not yet been conducted. Methods The research was designed as a controlled clinical study of patients with coronary artery disease undergoing surgical myocardial revascularization with or without the use of a cardiopulmonary bypass machine. All patients completed a battery of neuropsychological tests and plasmatic Aβ1-42 concentrations were collected. Results The neuropsychological test results postoperatively were significantly worse in the cardiopulmonary bypass group and the patients had larger shifts in the Aβ1-42 preoperative and postoperative values than the group in which off-pump coronary artery bypass was performed. Conclusions The conducted research confirmed the earlier suspected association of plasmatic Aβ1-42 concentration to postoperative cognitive decline and the results further showed that there were less changes and lower concentrations in the off-pump coronary artery bypass group, which correlated to less neurocognitive decline. There is a lot of clinical contribution acquired by this research, not only in everyday decision making and using amyloid proteins as biomarkers, but also in the development and application of non-pharmacological and pharmacological neuroprotective strategies.

Predictors of perioperative myocardial infarction in patients undergoing off-pump coronary artery bypass grafting

Background Perioperative myocardial infarction (PMI) increases morbidity and mortality after off-pump coronary artery bypass grafting (CABG). The objective of the current study was to characterize patients with PMI after off-pump CABG and identify its predictors. Results We included 1181 patients who had off-pump CABG from 2010 to 2020; 59 patients (5%) had PMI. We compared patients with PMI to those without PMI. Patients with PMI were older (57 (25th–75th percentiles: 51–63) vs. 54 (48–60) years; P = 0.01) and had higher NYHA class (28 (47.46%) vs. 326 (29.06%): P = 0.01). The distal anastomosis time was longer in patients with PMI (28 (23–35) vs. 24 (16–30) min; P ˂ 0.001). Patients with PMI had higher postoperative low cardiac output (10 (18.18%) vs. 1 (0.1%): P ˂ 0.001), prolonged ventilation (12 (8–39) vs. 8 (6–10) h, P ˂ 0.001), ICU (71 (46–138) vs. 24 (23–42) h; P ˂ 0.001), and hospital stay (9 (6–15) vs. 7 (6–8) days; P ˂ 0.001). Mortality was significantly higher in patients with PMI (20 (33.9%) vs. 6 (0.53%); P ˂ 0.001). Older age (OR: 1.05 (95% CI: 1.01–1.1); P = 0.02), increased number of distal anastomoses (OR: 1.74 (95% CI: 1.20–2.50); P = 0.003), preoperative congestive heart failure (OR: 10.27 (95% CI: 2.58–40.95); P = 0.001), and thrombolysis within 24 h of surgery (OR: 15.34 (1.93–121.9); P = 0.01) were associated with increased PMI, while PMI was lower in male patients (OR: 0.42 (95% CI: 0.19–0.93); P = 0.03) and with higher body surface area (BSA) (OR: 0.08 (95% CI: 0.07–0.86); P = 0.04). Conclusions Post-off-pump CABG PMI was associated with increased morbidity and mortality. Risk factors for PMI were older age, lower BSA, females, increased distal anastomoses, preoperative heart failure, and thrombolysis.

The Prognostic Significance of Neutrophil to Lymphocyte Ratio (NLR), Monocyte to Lymphocyte Ratio (MLR) and Platelet to Lymphocyte Ratio (PLR) on Long-Term Survival in Off-Pump Coronary Artery Bypass Grafting (OPCAB) Procedures

Background: Cardiovascular diseases, apart from commonly known risk factors, are related to inflammation. There are several simple novel markers proposed to present the relation between inflammatory reactions activation and atherosclerotic changes. They are easily available from whole blood count and include neutrophil to lymphocyte ratio (NLR), monocyte to lymphocyte ratio (MLR), and platelets to lymphocyte ratio (PLR). The RDW results were excluded from the analysis. Method and results: The study based on retrospective single-centre analysis of 682 consecutive patients (131 (19%) females and 551 (81%) males) with median age of 66 years (60–71) who underwent off-pump coronary artery bypass grafting (OPCAB) procedure. During the median 5.3 +/− 1.9 years follow-up, there was a 87% cumulative survival rate. The laboratory parameters including preoperative MLR > 0.2 (HR 2.46, 95% CI 1.33–4.55, p = 0.004) and postoperative NLR > 3.5 (HR 1.75, 95% CI 1.09–2.79, p = 0.019) were found significant for long-term mortality prediction in multivariable analysis. Conclusion: Hematological indices NLR and MLR can be regarded as significant predictors of all-cause long-term mortality after OPCAB revascularization. Multivariable analysis revealed preoperative values of MLR > 0.2 and postoperative values of NLR > 3.5 as simple, reliable factors which may be applied into clinical practice for meticulous postoperative monitoring of patients in higher risk of worse prognosis.

One-Stop Hybrid Coronary Revascularization Versus Off-Pump Coronary Artery Bypass Grafting in Patients With Multivessel Coronary Artery Disease

Background: Data on one-stop hybrid coronary revascularization (HCR) are limited. This study aimed to compare the early and midterm outcomes of one-stop HCR with off-pump coronary artery bypass grafting (OPCAB) in patients with multivessel coronary artery disease.Methods: From April 2018 to May 2021, 752 patients with multivessel coronary artery disease who underwent isolated one-stop HCR or OPCAB were retrospectively included in this analysis. After exclusion and propensity score matching, 151 patients who underwent HCR were matched with 151 patients who underwent OPCAB. The primary endpoints were midterm major adverse cardiovascular and cerebrovascular events (MACCE) after the procedure. The secondary endpoints were in-hospital complications and outcomes.Results: The preprocedural characteristics were well balanced between the two groups after matching. The HCR group was associated with a lower rate of perioperative transfusion (23.8 vs. 53.0%, p < 0.001) and new-onset atrial fibrillation (AF) (5.3 vs. 15.2%, p = 0.004), shorter time of mechanical ventilation (h) [15 (16, 17) vs. 17 (16, 20), p < 0.001], and shorter length of stay (LOS) in the hospital (days) [19 (16, 24) vs. 22 (18, 27), p = 0.001]. Cumulated MACCE rates were similar between the two groups (15.9 vs. 14.0%, p = 0.59) during a median follow-up of 20 months.Conclusions: One-stop HCR is safe and efficacious with less invasiveness and faster postoperative recovery in selected patients with multivessel coronary artery disease. Randomized controlled trials with larger sample sizes and long-term follow-up are warranted to confirm these findings.

Intraoperative Mild Hyperoxia May be Associated with Improved Survival After Off-Pump Coronary Artery Bypass Grafting: A Retrospective Observational Study

Background: The effect of hyperoxia due to supplemental oxygen administration on postoperative outcomes in patients undergoing cardiac surgery remains unclear. This retrospective study aimed to evaluate the relationship between intraoperative oxygen tension and mortality after off-pump coronary artery bypass grafting (OPCAB).Methods: The study included adult patients who underwent isolated OPCAB between July 2010 and June 2020. Patients were categorised into three groups based on their intraoperative time-weighted average arterial oxygen partial pressure (PaO2): normoxia/near-normoxia (<150 mmHg), mild hyperoxia (150–250 mmHg), and severe hyperoxia (>250 mmHg). The risk of in-hospital mortality was compared using weighted logistic regression analysis. Restricted cubic spline analysis was performed to analyse intraoperative PaO2 as a continuous variable. The risk of cumulative all-cause mortality was compared using Cox regression analysis.Results: The normoxia/near-normoxia, mild hyperoxia, and severe hyperoxia groups included 229, 991, and 173 patients (n=1,393), respectively. The mild hyperoxia group had a significantly lower risk of in-hospital mortality than the normoxia/near-normoxia (odds ratio [OR], 0.12; 95% confidence interval [CI], 0.06–0.22) and severe hyperoxia groups (OR, 0.06; 95% CI, 0.03–0.14). Intraoperative PaO2 exhibited a U-shaped relationship with in-hospital mortality in the non-hypoxic range. The risk of cumulative all-cause mortality was significantly lower in the mild hyperoxia group (hazard ratio, 0.72; 95% CI, 0.52–0.99) than in the normoxia/near-normoxia group.Conclusions: Intraoperative mild hyperoxia was associated with a lower risk of mortality after OPCAB than normoxia, near-normoxia, or severe hyperoxia. Mildly increasing arterial oxygen tension during OPCAB may help to optimise postoperative outcomes.Trial registration: Not applicable.

Off-pump coronary artery bypass with heparin in a patient with a history of heparin-induced thrombocytopenia: a case report

Background Cardiovascular surgery for patients with a history of heparin-induced thrombocytopenia (HIT) with thrombosis requires careful perioperative anticoagulation therapy. When cardiovascular surgery is required for patients having ‘remote’ HIT, such as those who had a history of HIT and platelet factor-4/heparin antibodies turned out to be negative, it is recommended that re-exposure to heparin should be limited only to the intraoperative phase. However, few case reports have described detailed strategies for perioperative anticoagulation regimens. Case presentation We present the case of a 76-year-old woman, presenting with unstable angina pectoris and requiring coronary artery bypass grafting. She had a history of cardiac resuscitation and percutaneous coronary intervention for unstable angina pectoris with ventricular tachycardia 7 years prior, which caused HIT with thrombosis resulting in amputation of four fingers. On admission, platelet factor-4/heparin antibodies, biomarkers for HIT were not detected; the platelet count was 18.0 × 104/µl. Off-pump coronary artery bypass grafting was performed using heparin; argatroban infusion was continued until 9 h prior to the operation and restarted 3 h postoperatively, bridged with regular warfarin from 4 days to 3 months postoperatively. Platelet factor-4 /heparin antibodies were detected on postoperative day 8 without any clinical symptoms and became negative by day 91. Conclusion We consider this anticoagulation strategy is effective especially in countries, where bivalirudin is not available. Re-exposure to heparin in cardiovascular surgery for patients with a history of ‘remote HIT’ is reasonable, and appropriate anticoagulation is important for an uneventful postoperative course.

Quality of Life After on Pump Coronary Artery Bypass Grafting Post Six Months with Cardiac Rehabilitation

Aim: To describe the quality of life six months following on-pump coronary artery bypass grafting in people aged 61 to 70. Methods: An analytical cross-sectional survey was conducted on 119 cardiovascular patients who have undergone On Pump CABG procedure. The data was collected from Punjab Institute of Cardiology and Omer Hospital Lahore. 70 patients were taken from Punjab Institute of Cardiology Lahore and 49 from Omer Hospital. Non-probability convenient sampling was used as a sampling approach. From August 2018 until January 2019, the research was conducted. The Medical Outcomes Study short form 36 (SF-36) questionnaires were used to determine the quality of life. Results: The mean age of the 119 patients was 65.23 + 3.35, with a standard deviation of 3.35. Three patients (2.5%) had energy fatigue, three (2.5%) had role limitations due to physical health, fifteen (12.6%) had role limitations due to emotional problems, 96 (80.7%) had physical functioning and two (1.7%) had emotional well-being, four (3.4%) had social functioning, three (2.5%) had pain, and three (2.5%) had general health problems. Conclusion: The quality of life of on-pump CABG patients aged 61-70 years after six months of cardiac rehabilitation was reported to be satisfactory, with improved activities of daily living. Keywords: Quality of life, on pump coronary artery bypasses grafting, cardiac rehabilitation

Stiffness Modelling and Performance Evaluation of a Soft Cardiac Fixator Flexible Arm with Granular Jamming

To meet the practical application requirements of cardiac fixation during off-pump coronary artery bypass surgery, a soft cardiac fixator with a flexible arm was previously designed. To enable the soft cardiac fixator to adapt to uncertain external forces, this study evaluates the variable-stiffness performance of the flexible arm. First, the flexible arm was simplified as a soft silicone manipulator measuring 60 mm × 90 mm × 120 mm, which can actuate, soften, or stiffen independently along the length of the arm by combining granular jamming with input pressure. Then, the soft manipulator was modelled as a cantilever beam to analyse its variable-stiffness performance with granular jamming. Next, based on theoretical analysis and calculations, many experiments were conducted to evaluate the variable-stiffness performance of the soft manipulator. The experimental results demonstrated that the variable-stiffness performance is influenced by the flexible arm length, the size of the granules, and the input pressure.