Fifty years of coronary artery bypass grafting

Is cardioplegia system pressure the optimal measure of coronary perfusion during antegrade cardioplegia delivery? A critical review of pressure measurements for optimal antegrade delivery

Antegrade cardioplegia is routinely given during cardiac surgery. The delivery of antegrade cardioplegia from the cardiopulmonary bypass machine has many variables. Many perfusionists rely exclusively on cardioplegia system pressure to ensure safe antegrade delivery. Our group reviewed antegrade cardioplegia delivery in 50 patients undergoing coronary artery bypass graft. The data collected included the cardioplegia system pressure and the patient's direct aortic root pressure. The analysis of the data found weak correlation between the two pressures with a large mean difference and a wide standard deviation. The results suggest the direct measurement of aortic root pressure as guidance to antegrade cardioplegia instead of relying solely on cardioplegia system pressure.

Examination of Postoperative Changes in Lipid Profile and Glycemic Markers After Coronary Artery Bypass Graft, Percutaneous Intervention Vs Aortic Valve Replacement Demonstrated a Shift in Risk Factors for Coronary Artery Disease

Purpose

Surgery-related stress may affect the metabolome, leading to abnormal lipid profiles and ineffective glycemic control. Here, we gauge these changes as they may accelerate atherosclerosis, limiting the benefits of interventions aimed at improving coronary artery disease (CAD) progression.

Patients and Methods

Electronic medical records were queried to identify patients undergoing coronary artery bypass grafting (CABG), percutaneous coronary intervention (PCI), or aortic valve replacement (AVR). 7573 records denoted lipid profile (cholesterol, LDL, HDL, VLDL, triglycerides) and glucose metabolism impairment (HbA1c). Pre-procedure lipid and glucose laboratory values were compared with periods representing acute periprocedural inflammation (1-3 months), resolution of acute inflammation (3-6 months), convalescence (6-12 months), and medium- (1-2 years), and long-term periods (2-5 years).

Results

Baseline values differed between groups (AVR: Cholesterol↑↓, LDL↓↑, HDL↓, Triglycerides↑, HbA1c↓; CABG: Cholesterol↓, LDL↓, HDL↓, Triglycerides↓, HbA1c↓; PCI: Cholesterol↑↓, LDL↑↓, HDL↑↓, Triglycerides↓, HbA1c↓). Interestingly, total cholesterol and LDL had opposite trajectories after CABG vs AVR even five years after surgical procedure and the effects were moderate as denoted by d-Cohen statistics. HDL declined acutely after CABG and AVR but not after PCI. Triglycerides were elevated for 2 years after AVR but depressed after CABG and PCI. HbA1c remained depressed for up to 5 years after any studied procedure.

Conclusion

Our data suggest surgical procedures result in prolonged lipid profile and glycemic metabolism disturbances, particularly after aortic valve replacement, indicating more aggressive post-surgical treatment of these metabolic abnormalities may be warranted.

The outcomes of robotic-assisted coronary artery bypass grafting surgery in the Atlantic demographic-a systematic review and meta-analysis of the literature

Background

Coronary artery bypass grafting (CABG) has significantly reduced the morbidity and mortality of patients suffering from ischemic heart disease over its six decades of practice. In recent years, minimally invasive techniques have been increasingly described and utilized, with the promise of providing patients with the same standard of care without the need for the traditional full sternotomy, and in select cases without cardiopulmonary bypass, and thus providing improved recovery metrics. The present systematic review and meta-analysis sought to determine the outcomes of all patients receiving robotic-assisted CABG in an Atlantic patient demographic.

Methods

The methods for this systematic review and meta-analysis adhered to the Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) statement. Four databases were searched, using appropriate search terminology. Meta-analysis using proportions or means, as appropriate, were applied, and were presented as per routine practice. Kaplan-Meier curves were digitized and aggregated using previously reported, validated techniques. Quality assessment and risk of bias of each study were assessed systematically. Patient populations were subcategorized as per established technical definitions.

Results

Thirty-five studies were identified through the literature search, with three studies having subgroupings appropriate for separate analysis (yielding 42 data points maximally). A total of 9,078 patients (69% male), with a mean age of 62.3 years, were identified across the study period. On actuarial assessment, survival at yearly assessment from 1-, 2-, 3-, 4- and 5-yearly intervals was determined to be 95%, 94%, 92%, 90%, and 88%, respectively.

Conclusions

The present systematic review and meta-analysis demonstrated that short-term mortality, operative time, and admission [intensive care unit (ICU) and overall length of stay] outcomes were encouraging in the Atlantic demographic. Freedom from long-term mortality assessment of a smaller cohort showed encouraging results. A major caveat to the present analysis is the high degree of heterogeneity in the reporting of data. Analysis of future randomized controlled trials will be vital in establishing these procedures as commonplace.

Potassium Supplementation and Prevention of Atrial Fibrillation After Cardiac Surgery: The TIGHT K Randomized Clinical Trial

IMPORTANCE

Supplementing potassium in an effort to maintain high-normal serum concentrations is a widespread strategy used to prevent atrial fibrillation after cardiac surgery (AFACS), but is not evidence-based, carries risks, and is costly.

OBJECTIVE

To determine whether a lower serum potassium concentration trigger for supplementation is noninferior to a high-normal trigger.

DESIGN, SETTING, AND PARTICIPANTS

This open-label, noninferiority, randomized clinical trial was conducted at 23 cardiac surgical centers in the United Kingdom and Germany. Between October 20, 2020, and November 16, 2023, patients with no history of atrial dysrhythmias scheduled for isolated coronary artery bypass grafting (CABG) surgery were enrolled. The last study patient was discharged from the hospital on December 11, 2023.

INTERVENTIONS

Patients were randomly assigned to a strategy of tight or relaxed potassium control (only supplementing if serum potassium concentration fell below 4.5 mEq/L or 3.6 mEq/L, respectively). Patients wore an ambulatory heart rhythm monitor, which was analyzed by a core laboratory masked to treatment assignment.

MAIN OUTCOMES AND MEASURES

The prespecified primary end point was clinically detected and electrocardiographically confirmed new-onset AFACS in the first 120 hours after CABG surgery or until hospital discharge, whichever occurred first. All primary outcome events were validated by an event validation committee, which was masked to treatment assignment. Noninferiority of relaxed potassium control was defined as a risk difference for new-onset AFACS with associated upper bound of a 1-sided 97.5% CI of less than 10%. Secondary outcomes included other heart rhythm-related events, clinical outcomes, and cost related to the intervention.

RESULTS

A total of 1690 patients (mean age, 65 years; 256 [15%] females) were randomized. The primary end point occurred in 26.2% of patients (n = 219) in the tight group and 27.8% of patients (n = 231) in the relaxed group, which is a risk difference of 1.7% (95% CI, -2.6% to 5.9%). There was no difference between the groups in the incidence of at least 1 AFACS episode detected by any means or by ambulatory heart rhythm monitor alone, non-AFACS dysrhythmias, in-patient mortality, or length of stay. Per-patient cost for purchasing and administering potassium was significantly lower in the relaxed group (mean difference, $111.89 [95% CI, $103.60-$120.19]; P <.001).

CONCLUSIONS AND RELEVANCE

For AFACS prophylaxis, supplementation only when serum potassium concentration fell below 3.6 mEq/L was noninferior to the current widespread practice of supplementing potassium to maintain a serum potassium concentration greater than or equal to 4.5 mEq/L. The lower threshold of supplementation was not associated with any increase in dysrhythmias or adverse clinical outcomes.

TRIAL REGISTRATION

ClinicalTrials.gov Identifier: NCT04053816.

A systematic review and meta-analysis of differences between men and women in short-term outcomes following coronary artery bypass graft surgery

We provide an update regarding the differences between men and women in short-term postoperative mortality after coronary artery bypass grafting (CABG) and highlight the differences in postoperative risk of stroke, myocardial infarction, and new onset atrial fibrillation. We included 23 studies, with a total of 3,971,267 patients (70.7% men, 29.3% women), and provided results for groups of unbalanced studies and propensity matched studies. For short-term mortality, the pooled odds ratio (OR) from unbalanced studies was 1.71 (with 95% CI 1.69-1.74, I2 = 0%, p = 0.7), and from propensity matched studies was 1.32 (95% CI 1.14-1.52, I2 = 76%, p < 0.01). For postoperative stroke, the pooled effects were OR = 1.50 (95% CI 1.35-1.66, I2 = 83%, p < 0.01) and OR = 1.31 (95% CI 1.02-1.67, I2 = 81%, p < 0.01). For myocardial infarction, the pooled effects were OR = 1.09 (95% CI = 0.78-1.53, I2 = 70%, p < 0.01) and OR = 1.03 (95% CI = 0.86-1.24, I2 = 43%, p = 0.18). For postoperative atrial fibrillation, the pooled effect from unbalanced studies was OR = 0.89 (95% CI = 0.82-0.96, I2 = 34%, p = 0.18). The short-term mortality risk after CABG is higher in women, compared to men. Women are at higher risk of postoperative stroke. There is no significant difference in the likelihood of postoperative myocardial infarction in women compared to men. Men are at higher risk of postoperative atrial fibrillation after CABG.

Totally endoscopic coronary artery bypass grafting: experience in 1500 patients

OBJECTIVES

Totally endoscopic coronary artery bypass grafting (TECAB) is a minimally invasive approach to achieve surgical revascularization through a minimally invasive approach. Still, data regarding non-robotic TECAB are limited. This report presents the results of a TECAB technique using long-shafted instruments, defined as Endo-CABG, from a single-centre experience in 1500 consecutive patients.

METHODS

One thousand and five hundred patients underwent Endo-CABG between January 2016 and February 2023. Data were collected retrospectively, and patients were followed up for 1 year. The primary outcome of this study was major adverse cardiac and cerebrovascular events (MACCE)-free survival. Secondary efficacy outcomes were graft failure and mortality. Furthermore, we analysed factors influencing long-term freedom from MACCE and all-cause mortality.

RESULTS

The mean age was 68 [61-75] years, of which 193 (12.87%) were octogenarians. Multivessel disease was present in 1409 (93.93%) patients, and the mean EuroSCORE II was 1.64 [1.09-2.92] %. All patients underwent full arterial revascularization with bilateral internal mammary grafting in 88.47%. Graft failure occurred in 1.80% of cases after 1 year (n = 27). Thirty-day mortality was 1.73% (n = 26), 1-year survival was 94.7% (95% CI: 93.5-95.9%; n = 26) and 1-year MACCE-free survival was 91.7% (95% CI: 90.2-93.2%). Age, left ventricular ejection fraction, arterial hypertension and urgency were significantly associated with 1-year MACCE-free survival.

CONCLUSIONS

Endo-CABG appears to be a safe procedure, achieves surgical revascularization and provides good outcomes regarding graft failure and MACCE at 1 year, while age, left ventricular ejection fraction, arterial hypertension and urgency were associated with 1-year outcomes.

Transcriptomic responses of peripheral blood leukocytes to cardiac surgery after acute inflammation, and three months recovery

Traumatic perioperative conditions may trigger early systemic responses, activate leukocytes and reprogram the immune system. We hypothesize that leukocyte activation may not revert to pre-surgical states, and that protracted activation may emerge with increased risks of comorbidities. We tested this concept by examining the transcriptomes of monocytes and T cells in a representative observational cohort of patients (n = 13) admitted for elective cardiac surgery. Transcriptomes in T cells and monocytes were compared from before surgery (t0), and monocytes were analyzed longitudinally after acute (t24hr), and convalescent (t3m) time points. Monocytes and T cells expressed distinct transcriptomes, reflected by statistically significant differential expression of 558 T cell related genes. Monocytes expressed genes related to protein degradation and presented atypical activation of surface markers and cytoplasmic functions over time. Additionally, monocytes exhibited limited transcriptomic heterogeneity prior to surgery, and long-term patterns of gene expression associated with atherosclerosis showed three temporally distinct signatures. These data establish that post-cardiac surgery transcriptomes of monocytes differ even at three months compared to baselines, which may reflect latent ('smoldering') inflammation and persistent progression of tissue degenerative processes that should inform clinical care.

Coronary artery bypass grafting vs. drug-eluting stent implantation: the probabilities of reintervention, transition to severe care-need, nursing home, and death in patients with coronary artery disease within the first three years: evaluations based on health claims data in Germany

Background

Coronary artery bypass grafting (CABG) and drug-eluting stent implantation (DES) are established as central methods of revascularization for patients with coronary artery disease. This study aims to analyse the health trajectories of patients after first CABG or first, second or third DES within the first three years, with a focus on follow-up interventions, severe care need, transition into a nursing home, and death.

Methods

Based on health claims data (n=11,581), we estimated age-and sex standardized probabilities of reintervention, and of transition to severe care need, nursing home and death following initial CABG (n=2,008) or DES (n=9,573) for patients aged 50 years and older using logistic regression models and direct standardization. Up to three follow-up DES interventions and one follow-up CABG were considered.

Results

There was a fairly high probability of reintervention, particularly after a DES and within the first year. Follow-up interventions were more likely to involve DES than CABG. The probability of death was notably higher for CABG patients. The probabilities of severe care need and moving to a nursing home were slightly lower and similar across the revascularization methods and over time.

Conclusions

DES and CABG are often associated with a need for follow-up interventions. Depending on the procedure, however, the risk of repeat surgery or adverse health outcomes varies. DES is associated with a relatively high probability of follow-up revascularization and a nearly constant probability of negative health outcomes in the short and medium term. In contrast, within three years after a CABG, follow-up reinterventions are rather rare. However, this procedure is particularly associated with an increased risk of mortality and short-term transition into a nursing home.

A Single-Surgeon Experience Transitioning to Total Arterial Revascularization

Background: Coronary artery bypass grafting remains the standard of care for advanced and multifocal coronary artery disease; however, for patients that are surgical candidates, total arterial revascularization (TAR) remains underutilized due to concerns such as sternal wound infections and the learning curve. We present the results of a large cohort of mid-career surgeons transitioning to TAR, focusing on short-term outcomes and the learning curve. Methods: The surgeons transitioned to using TAR as the preferred revascularization technique in August of 2017. The Society of Thoracic Surgeons database was reviewed to identify all patients who underwent isolated non-emergent CABG performed by a single surgeon from January 2014 through January 2022. Patients were divided into two groups-those who had TAR and those who had traditional CABG using one internal mammary artery and vein grafts (IMA-SVG). Results: Eight hundred ninety-eight patients meet inclusion criteria (458 IMA-SVG and 440 TAR). The TAR group had slightly longer cardiopulmonary bypass time, cross clamp times, and operative times (all p < 0.05); however, ICU stay was shorter and 30-day readmission rate was lower for TAR compared to IMA-SVG (all p < 0.05). The TAR group also required fewer postoperative transfusions (p = 0.005). There was no difference in prolonged intubation, stroke, length of stay, mortality, or sternal wound complications between groups (all p > 0.05). The average TAR was 30 min longer; however, learning curves, stratified by number of grafts placed, showed no significant learning curve associated with TAR. Conclusions: An experienced surgeon transitioning from IMA-SVG to TAR slightly increases operative time, but decreases ICU stay, readmissions, and postoperative transfusions with no significant difference in rates of immediate post-operative complications or 30-day mortality, with a minimal learning curve.

Machine learning prediction of hospitalization costs for coronary artery bypass grafting operations

BACKGROUND

With the steady rise in health care expenditures, the examination of factors that may influence the costs of care has garnered much attention. Although machine learning models have previously been applied in health economics, their application within cardiac surgery remains limited. We evaluated several machine learning algorithms to model hospitalization costs for coronary artery bypass grafting.

METHODS

All adult hospitalizations for isolated coronary artery bypass grafting were identified in the 2016 to 2020 Nationwide Readmissions Database. Machine learning models were trained to predict expenditures and compared with traditional linear regression. Given the significance of postoperative length of stay, we additionally developed models excluding postoperative length of stay to uncover other drivers of costs. To facilitate comparison, machine learning classification models were also trained to predict patients in the highest decile of costs. Significant factors associated with high cost were identified using SHapley Additive exPlanations beeswarm plots.

RESULTS

Among 444,740 hospitalizations included for analysis, the median cost of hospitalization in coronary artery bypass grafting patients was $43,103. eXtreme Gradient Boosting most accurately predicted hospitalization costs, with R2 = 0.519 over the validation set. The top predictive features in the eXtreme Gradient Boosting model included elective procedure status, prolonged mechanical ventilation, new-onset respiratory failure or myocardial infarction, and postoperative length of stay. After removing postoperative length of stay, eXtreme Gradient Boosting remained the most accurate model (R2 = 0.38). Prolonged ventilation, respiratory failure, and elective status remained important predictive parameters.

CONCLUSION

Machine learning models appear to accurately model total hospitalization costs for coronary artery bypass grafting. Future work is warranted to uncover other drivers of costs and improve the value of care in cardiac surgery.

More Hospital Complications in Women after Cabg Even for Reduced Surgical Times: Call to Action for Equity in Quality Improvement

BACKGROUND

Analyses of extensive registries indicate adverse outcomes for women undergoing coronary artery bypass grafting (CABG) surgery, while randomized studies often lack representativeness.

OBJECTIVE

To compare adjusted hospital outcomes between men and women undergoing CABG.

METHODS

From July 2017 to June 2019, 3991 patients underwent primary isolated CABG, both electively and urgently, in 5 hospitals in the state of São Paulo, Brazil. To mitigate demographic differences between men and women, populations were adjusted using propensity score matching (PSM). The outcomes considered for analysis were those used by the STS Adult Database. The analyses were performed using R software, with a significance set at p<0.05.

RESULTS

After PSM (1:1), each group included 1089 patients. Regarding intraoperative variables, men exhibited longer cardiopulmonary bypass (CPB) time (p<0.001), surgical time (p<0.001), a higher number of distal anastomoses (p<0.001), and increased use of arterial grafts. Regarding outcomes, women had a higher incidence of deep sternal wound infection (p=0.006), prolonged Intensive Care Unit stay (p=0.002), increased need for an intra-aortic balloon pump (p=0.04), higher blood transfusion rates (p<0.001), higher 30-day hospital readmission rates after surgery (p=0.002) and higher mortality rate (p=0.03).

CONCLUSIONS

Although men had longer CPB times, a greater number of arterial grafts, and a greater number of distal anastomoses, immediate results after CABG were poorer in women.

Methadone in combination with magnesium, ketamine, lidocaine, and dexmedetomidine improves postoperative outcomes after coronary artery bypass grafting: an observational multicentre study

BACKGROUND

An optimal pharmacological strategy for fast-track cardiac anesthesia (FTCA) is unclear. This study evaluated the effectiveness and safety of an FTCA program using methadone and non-opioid adjuvant infusions (magnesium, ketamine, lidocaine, and dexmedetomidine) in patients undergoing coronary artery bypass grafting.

METHODS

This retrospective, multicenter observational study was conducted across private and public teaching sectors. We studied patients managed by a fast-track protocol or via usual care according to clinician preference. The primary outcome was the total mechanical ventilation time in hours adjusted for hospital, body mass index, category of surgical urgency, cardiopulmonary bypass time and EuroSCORE II. Secondary outcomes included successful extubation within four postoperative hours, postoperative pain scores, postoperative opioid requirements, and the development of postoperative complications.

RESULTS

We included 87 patients in the fast-track group and 88 patients in the usual care group. Fast-track patients had a 35% reduction in total ventilation hours compared with usual care patients (p = 0.007). Thirty-five (40.2%) fast-track patients were extubated within four hours compared to 10 (11.4%) usual-care patients (odds ratio: 5.2 [95% CI: 2.39-11.08; p < 0.001]). Over 24 h, fast-track patients had less severe pain (p < 0.001) and required less intravenous morphine equivalent (22.00 mg [15.75:32.50] vs. 38.75 mg [20.50:81.75]; p < 0.001). There were no significant differences observed in postoperative complications or length of hospital stay between the groups.

CONCLUSION

Implementing an FTCA protocol using methadone, dexmedetomidine, magnesium, ketamine, lignocaine, and remifentanil together with protocolized weaning from a mechanical ventilation protocol is associated with significantly reduced time to tracheal extubation, improved postoperative analgesia, and reduced opioid use without any adverse safety events. A prospective randomized trial is warranted to further investigate the combined effects of these medications in reducing complications and length of stay in FTCA.

TRIALS REGISTRATION

The study protocol was registered in the Australian New Zealand Clinical Trials Registry ( https://www.anzctr.org.au/ACTRN12623000060640.aspx , retrospectively registered on 17/01/2023).

Nonlinear Elasticity of Blood Vessels and Vascular Grafts

The transplantation of vascular grafts has emerged as a prevailing approach to address vascular disorders. However, the development of small-diameter vascular grafts is still in progress, as they serve in a more complicated mechanical environment than their counterparts with larger diameters. The biocompatibility and functional characteristics of small-diameter vascular grafts have been well developed; however, mismatch in mechanical properties between the vascular grafts and native arteries has not been accomplished, which might facilitate the long-term patency of small-diameter vascular grafts. From a point of view in mechanics, mimicking the nonlinear elastic mechanical behavior exhibited by natural blood vessels might be the state-of-the-art in designing vascular grafts. This review centers on elucidating the nonlinear elastic behavior of natural blood vessels and vascular grafts. The biological functionality and limitations associated with as-reported vascular grafts are meticulously reviewed and the future trajectory for fabricating biomimetic small-diameter grafts is discussed. This review might provide a different insight from the traditional design and fabrication of artificial vascular grafts.

Epicardial placement of human placental membrane allografts in coronary artery bypass graft surgery is associated with reduced postoperative atrial fibrillation: a pilot study for a future multi-center randomized controlled trial

BACKGROUND

Post-operative atrial fibrillation (POAF) occurs in up to 40% of patients following coronary artery bypass grafting (CABG) and is associated with a higher risk of stroke and mortality. This study investigates how POAF may be mitigated by epicardial placement of aseptically processed human placental membrane allografts (HPMAs) before pericardial closure in CABG surgery. This study was conducted as a pilot feasibility study to collect preliminary for a forthcoming multi-center randomized controlled trial.

METHODS

This retrospective observational study of patients undergoing CABG surgery excluded patients with pre-operative heart failure, chronic kidney disease, or a history of atrial fibrillation. The "treatment" group (n = 24) had three HPMAs placed epicardially following cardiopulmonary bypass decannulation but before partial pericardial approximation and chest closure. The only difference in clinical protocol for the control group (n = 54) was that they did not receive HPMA.

RESULTS

HPMA-treated patients saw a significant, greater than four-fold reduction in POAF incidence compared to controls (35.2-8.3%, p = 0.0136). Univariate analysis demonstrated that HPMA treatment was associated with an 83% reduction in POAF (OR = 0.17, p = 0.0248). Multivariable analysis yielded similar results (OR = 0.07, p = 0.0156) after controlling for other covariates. Overall length of stay (LOS) between groups was similar, but ICU LOS trended lower with HPMA treatment (p = 0.0677). Post-operative inotrope and vasopressor requirements were similar among groups. There was no new-onset post-operative heart failure, stroke, or death reported up to thirty days in either group.

CONCLUSIONS

Epicardial HPMA placement can be a simple intervention at the end of CABG surgery that may provide a new approach to reduce post-operative atrial fibrillation by modulating local inflammation, possibly reducing ICU and hospital stay, and ultimately improving patient outcomes.

Impact of cryopreservation on elastomuscular artery mechanics

Low temperatures slow or halt undesired biological and chemical processes, protecting cells, tissues, and organs during storage. Cryopreservation techniques, including controlled media exchange and regulated freezing conditions, aim to mitigate the physical consequences of freezing. Dimethyl sulfoxide (DMSO), for example, is a penetrating cryoprotecting agent (CPA) that minimizes ice crystal growth by replacing intracellular water, while polyvinyl alcohol (PVA) is a nonpenetrating CPA that prevents recrystallization during thawing. Since proteins and ground substance dominate the passive properties of soft biological tissues, we studied how different freezing rates, storage temperatures, storage durations, and the presence of cryoprotecting agents (5% [v/v] DMSO + 1 mg/mL PVA) impact the histomechanical properties of the internal thoracic artery (ITA), a clinically relevant blood vessel with both elastic and muscular characteristics. Remarkably, biaxial mechanical analyses failed to reveal significant differences among the ten groups tested, suggesting that mechanical properties are virtually independent of the cryopreservation technique. Scanning electron microscopy revealed minor CPA-independent delamination in rapidly frozen samples, while cryoprotected ITAs had better post-thaw viability than their unprotected counterparts using methyl thiazole-tetrazolium (MTT) metabolic assays, especially when frozen at a controlled rate. These results can be used to inform ongoing and future studies in vascular engineering, physiology, and mechanics.

How to harvest the left internal mammary artery-a randomized controlled trial

OBJECTIVES

It is uncertain whether Thunderbeat has a place in harvesting the left internal mammary artery (LIMA) and whether skeletonization is superior to pedicle-harvested LIMA. Some investigations have shown improved flowrates in the skeletonized graft. The aim of this study was to compare 3 groups of harvesting techniques: Pedicled, surgical skeletonized and skeletonized with Thunderbeat in terms of flow rates in the LIMA and postoperative in-hospital outcomes.

METHODS

Patients undergoing coronary artery bypass grafting with the LIMA to the anterior descending artery were randomized to pedicled (n = 56), surgical skeletonized (n = 55) and skeletonized with Thunderbeat (n = 54). Main outcomes were blood flow and pulsatility index in the graft.

RESULTS

No statistical difference between groups regarding flow in LIMA or pulsatility index. Similarly, no difference in postoperative bleeding or days of hospitalization. The duration of harvesting was faster for the pedicled technique compared with surgical skeletonized and skeletonized with Thunderbeat [mean total min: pedicled 20.2 min standard deviation (SD) ± 5.4; surgical skeletonized 28.6 min SD ± 8.7; skeletonized with Thunderbeat 28.3 min SD ± 9.11, P < 0.001]. No grafts discarded due to faulty harvesting and there was no graft failure within hospital stay.

CONCLUSIONS

We found no difference between the harvesting methods except for a significantly faster harvesting time with the pedicled technique. However, non-touch skeletonized LIMA harvesting with Thunderbeat seems to be an effective alternative to traditional surgical skeletonized LIMA. The future will reveal whether patency is harvesting dependent.

CLINICAL TRIAL REGISTRATION

ClinicalTrials.gov Identifier: NCT05562908.

Renal dysfunction in adults following cardiopulmonary bypass is linked to declines in S-nitroso hemoglobin: a case series

Background

Impaired kidney function is frequently observed in patients following cardiopulmonary bypass (CPB). Our group has previously linked blood transfusion to acute declines in S-nitroso haemoglobin (SNO-Hb; the main regulator of tissue oxygen delivery), reductions in intraoperative renal blood flow, and postoperative kidney dysfunction. While not all CPB patients receive blood, kidney injury is still common. We hypothesized that the CPB procedure itself may negatively impact SNO-Hb levels leading to renal dysfunction.

Materials and methods

After obtaining written informed consent, blood samples were procured immediately before and after CPB, and on postoperative day (POD) 1. SNO-Hb levels, renal function (estimated glomerular filtration rate; eGFR), and plasma erythropoietin (EPO) concentrations were quantified. Additional outcome data were extracted from the patients' medical records.

Results

Twenty-seven patients were enroled, three withdrew consent, and one was excluded after developing bacteremia. SNO-Hb levels declined after surgery and were directly correlated with declines in eGFR (R=0.48). Conversely, plasma EPO concentrations were elevated and inversely correlated with SNO-Hb (R=-0.53) and eGFR (R=-0.55). Finally, ICU stay negatively correlated with SNO-Hb concentration (R=-0.32).

Conclusion

SNO-Hb levels are reduced following CPB in the absence of allogenic blood transfusion and are predictive of decreased renal function and prolonged ICU stay. Thus, therapies directed at maintaining or increasing SNO-Hb levels may improve outcomes in adult patients undergoing cardiac surgery.

Comparison of clinical effects of coronary artery bypass grafting between left anterior small thoracotomy approach and lower-end sternal splitting approach

OBJECTIVE

To compare the clinical effects of coronary artery bypass grafting (CABG) between the left anterior small thoracotomy (LAST) and lower-end sternal splitting (LESS) approaches for coronary artery disease.

METHODS

In total, 110 patients who underwent LAST from October 2015 to December 2020 in Tianjin Chest Hospital were selected as the observation group. Patients who underwent the LESS approach during the same period were analyzed. The propensity score was calculated by a logistic regression model, and nearest-neighbor matching was used for 1:1 matching.

RESULTS

The length of hospital stay and ventilator support time were significantly shorter in the LAST than LESS group. The target vessels in the obtuse marginal branch and posterior left ventricular artery branch grafts were significantly more numerous in the LAST than LESS group, but those in the right coronary artery graft were significantly less numerous in the LAST group.

CONCLUSIONS

CABG using either the LAST or LESS approach is safe and effective, especially in low-risk patients. The LAST approach can achieve complete revascularization for multivessel lesions and has the advantages of less trauma and an aesthetic outcome. However, it requires a certain learning curve to master the surgical techniques and has specific surgical indications.

Cardiac interventions on total knee arthroplasty: a national inpatient sample-based analysis

BACKGROUND

Comorbid cardiovascular diseases have been associated with poor outcomes in total knee arthroplasty (TKA); however, our understanding of TKA with prior cardiac treatment procedures has largely been undocumented. In this study, we examined TKA patients who had undergone different cardiac interventions that addressed their condition. The purpose was to characterize and compare outcomes for a growing patient population not yet analyzed.

MATERIALS AND METHODS

The 2016-2019 Nationwide Inpatient Sample database was queried for 558,256 patients who had TKA (ICD-10CM). Backgrounds significant for pacemaker [PM] (n = 8025), coronary artery bypass [CABG] (n = 12,683), heart valve surgery [HV] (n = 4125), or coronary stent [CS] (n = 19,483) were compared against those without, across demographics, admission information, and various complications.

RESULTS

Cardiac interventions were associated with increased age, male gender, length of stay, and cost of care. CABG, and Stent groups had more diabetics, but HV had significantly fewer (p = 0.008). PM and HV had significantly less tobacco use and, in addition to CABG, less obesity. Postoperatively, mortality was elevated in the PM [Odds ratio (OR) 2.89, p = 0.008], CABG (OR 2.53, p = 0.006) and CS group (OR 1.94, p = 0.018), but not HV. Myocardial infarctions were elevated in the CABG (OR 3.874) and CS group (OR 5.11) (p < 0.001). PM, HV, and CS had increased odds of periprosthetic fracture by 2.15-fold (p < 0.001), 2.09-fold (p < 0.001), 1.29-fold (p = 0.011) respectively. HV saw increased periprosthetic mechanical complications (OR 1.48, p = 0.006). CABG increased the odds of deep surgical site infection 14.23-fold and CS 9.22-fold (p < 0.001). Postoperative pneumonia was increased in PM, CABG, and CS groups (OR 2.15,), (OR 2.21,), (OR 1.64,) (p < 0.001).

CONCLUSIONS

Patients who have undergone cardiac intervention are generally at risk for adverse stays. Furthermore, risk factors and complications vary between the groups. Our analysis emphasizes the importance of individualized medical care and as a basis for electing and informing patients for TKA.

Selecting the appropriate patients for coronary artery bypass grafting in ischemic cardiomyopathy-importance of myocardial viability

Patients who undergo coronary artery bypass graft (CABG) surgery in ischemic cardiomyopathy have a survival advantage over medical therapy at 10 years. The survival advantage of CABG over medical therapy is due to its ability to reduce future myocardial infarction, and by conferring electrical stability. The presence of myocardial viability does not provide a differential survival advantage for CABG over medical therapy. Presence of angina and inducible ischemia are also less predictive of outcome. Moreover, CABG is associated with significant early mortality. Hence, careful patient selection is more important for reducing the early mortality and improving the long-term outcome than relying on results of myocardial viability. Younger patients with good exercise tolerance benefit the most, while patients who are frail and patients with renal dysfunction and dysfunctional right ventricle seem to have very high operative mortality. Elderly patients, because of poor life expectancy, do not benefit from CABG, but the age cutoff is not clear. Patients also need to have revascularizable targets, but this decision is often based on experience of the surgical team and heart team discussion. These recommendations are irrespective of the myocardial viability tests. Optimal medical treatment remains the cornerstone for management of ischemic cardiomyopathy.

Triple-Vessel Disease in a High-Risk Surgical Patient Treated With Nine Drug-Eluting Stents

Coronary artery disease (CAD) is a major cause of morbidity and mortality in the United States, and as strides have been made in its management, outcomes have continued to improve. Management has evolved from expectant management to coronary artery bypass graft surgery and thrombolysis, to more recently percutaneous intervention with stenting and medical management in select cases. Here, we describe a case of a complex patient with severe triple-vessel disease who was deemed a poor surgical candidate for coronary artery bypass graft surgery and would instead undergo high-risk percutaneous intervention with the placement of nine drug-eluting stents.

Postoperative acute kidney injury increases short- and long-term death risks in elderly patients (≥ 75 years old) undergoing coronary artery bypass graft surgery

PURPOSE

To explore the incidence of postoperative acute kidney injury (AKI) after coronary artery bypass grafting (CABG) in elderly Chinese patients (≥ 75 years old) and its impacts on the short- and long-term prognosis.

METHODS

A total of 493 patients aged 75-88 years old who underwent CABG from two medical centers between January 2006 and October 2021 were involved. Perioperative (preoperative and 7 days after operation) serum creatinine (Scr) levels were measured in all the enrolled patients. Univariate and multivariate logistic regression analyses were conducted to explore the independent risk factors of postoperative in-hospital mortality. Kaplan-Meier curves and COX model were used to test the risk factors of all-cause death during follow-up. Propensity score matching was used to balance differences between AKI and control groups. The primary outcome event was in-hospital death, and the secondary outcome was all-cause death during follow-up.

RESULTS

The 198 patients were diagnosed with postoperative AKI. Intra-aortic balloon pump (IABP), cardiopulmonary bypass, and postoperative AKI were independent risk factors of in-hospital death. Gender, New York Heart Association Classification, preoperative eGFR, last eGFR within 7 days after operation, postoperative AKI, and postoperative renal function all impacted long-term prognosis. After 1:1 matching, 190 patients were included in the AKI and control groups. Use of IABP, use of cardiopulmonary bypass, and occurrence of postoperative AKI were still independent risk factors of in-hospital death. Preoperative eGFR, last eGFR within 7 days after operation, postoperative AKI and postoperative renal function all impacted long-term prognosis.

CONCLUSION

The incidence of postoperative AKI in elderly patients undergoing CABG is high, and postoperative AKI is an independent risk factor of both short- and long-term postoperative prognosis.

Preoperative C-reactive protein/albumin ratio and mortality of off-pump coronary artery bypass graft

Background

We sought to investigate the prognostic value of preoperative C-reactive protein (CRP)-to-albumin ratio (CAR) for the prediction of mortality in patients undergoing off-pump coronary artery bypass grafting (OPCAB).

Methods

From January 2010 to August 2016, adult patients undergoing OPCAB were analyzed retrospectively. In a total of 2,082 patients, preoperative inflammatory markers including CAR, CRP, neutrophil-to-lymphocyte ratio, and platelet-to-lymphocyte ratio were recorded. Receiver operating characteristic (ROC) curves were used to determine the optimal threshold and compare the predictive values of the markers. The patients were divided into two groups according to the cut-off value of CAR, and then the outcomes were compared. The primary end point was 1-year mortality.

Results

During the 1-year follow-up period, 25 patients (1.2%) died after OPCAB. The area under the curve of CAR for 1-year mortality was 0.767, which was significantly higher than other inflammatory markers. According to the calculated cut-off value of 1.326, the patients were divided into two groups: 1,580 (75.9%) patients were placed in the low CAR group vs. 502 (24.1%) patients in the high CAR group. After adjustment with inverse probability weighting, high CAR was significantly associated with increased risk of 1-year mortality after OPCAB (Hazard ratio, 5.01; 95% Confidence interval, 2.01-12.50; p < 0.001).

Conclusions

In this study, we demonstrated that preoperative CAR was associated with 1-year mortality following OPCAB. Compared to previous inflammatory markers, CAR may offer superior predictive power for mortality in patients undergoing OPCAB. For validation of our findings, further prospective studies are needed.

Hospital Discharge Process: Context-Sensitive Care

The transition from hospital to home after surgery is a vulnerable time for all cardiac surgical patients, particularly older adults. This postoperative phase presents multiple physical, physiological, emotional, and socioeconomic challenges, not only for patients but also for their families and informal caregivers, who often describe this period as stressful and overwhelming. Health-care professionals, particularly nurses, play an integral role in a patient's discharge process; the challenges can be ameliorated through timely discharge planning and effective discharge education. The context-sensitive solutions shared in this paper propose enhancing nurses' discharge practices to provide individualized care and to facilitate the hospital-to-home transition.

Frailty efficacy as a predictor of clinical and cognitive complications in patients undergoing coronary artery bypass grafting: a prospective cohort study

BACKGROUND

Frailty is proposed as a predictor of outcomes in patients undergoing major surgeries, although data on the association of frailty and coronary artery bypass grafting (CABG) are lacking. We assessed the association between frailty and cognitive and clinical complications following CABG.

METHODS

This prospective study included patients aged over 60 years undergoing elective CABG at Tehran Heart Center from 2020 to 2022. Baseline and three-month follow-up data on frailty using the Frail scale and clinical Frail scale, functional status using the Lawton Instrumental Activities of Daily Living Scale (IADL), cognitive function by Montreal Cognitive Assessment (MoCA), and depression by the Geriatric Depression Scale (GDS) were obtained. The incidence of adverse outcomes was investigated at the three-month follow-up. Outcomes between frail and non-frail groups were compared utilizing T-tests and Mann-Whitney U tests, as appropriate.

RESULTS

We included 170 patients with a median age of 66 ± 4 years (75.3% male). Of these, 58 cases were classified as frail, and 112 individuals were non-frail, preoperatively. Frail patients demonstrated significantly worse baseline MOCA scores (21.08 vs. 22.41, P = 0.045), GDS (2.00 vs. 1.00, P = 0.009), and Lawton IADL (8.00 vs. 6.00, P < 0.001) compared to non-frail. According to 3-month follow-up data, postoperative MOCA and GDS scores were comparable between the two groups, while Lawton IADL (8.00 vs. 6.00, P < 0.001) was significantly lower in frail cases. A significantly higher rate of readmission (1.8% vs. 12.1%), sepsis (7.1% vs. 19.0%), as well as a higher Euroscore (1.5 vs. 1.9), was observed in the frail group. A mildly significantly more extended ICU stay (6.00 vs. 5.00, p = 0.051) was shown in the frail patient.

CONCLUSION

Frailty showed a significant association with a worse preoperative independence level, cognitive function, and depression status, as well as increased postoperative complications.

Complexity of coronary artery disease and the release of cardiac biomarkers after CABG

Objective

In patients with complex coronary artery disease (CAD) undergoing cardiac surgery, myocardial protection might be impaired due to microvascular obstruction, resulting in myocardial injury and subsequent biomarker release. Therefore, this study investigated the correlation between the complexity of CAD, reflected by the SYNTAX Score, and the release of cardiac biomarkers after CABG.

Methods

In a consecutive series of 919 patients undergoing isolated CABG SYNTAX scores I and II were calculated to assess the complexity of CAD. Levels of high sensitivity cardiac troponin T (hs-cTnT) and creatine kinase-myocardial band (CK-MB) were routinely measured once before and serially after surgery. Patients were divided into tertiles according to their SYNTAX Scores I and II. Spearman correlations and regression models were performed to measure the degree of association between the release of hs-cTnT and CK-MB and the SYNTAX Scores.

Results

Patients with a higher SYNTAX Score I had more comorbidities reflected in a higher EuroSCORE II. Preoperatively, higher levels of cardiac biomarkers were found in patients with higher SYNTAX Score II. No correlation was observed between hs-cTnT, CK-MB and SYNTAX Score I or II. Regression models did not show any association between cardiac biomarkers and the complexity of CAD.

Conclusion

The complexity of CAD is not associated with the release of cardiac biomarkers after CABG. Factors influencing postoperative biomarker release need to be elucidated in future trials to include postoperative biomarker release into risk stratification models predicting outcome after cardiac surgery.

Anatomical study and meta-analysis of the episternal ossicles

Episternal ossicles (EO) are accessory bones located superior and posterior to the manubrium, representing an anatomical variation in the thoracic region. This study aimed to investigate the prevalence and developmental aspects of EO in global populations. The prevalence of EO in pediatric populations was assessed using the "Pediatric-CT-SEG" open-access data set obtained from The Cancer Imaging Archive, revealing a single incidence of EO among 233 subjects, occurring in a 14-year-old patient. A meta-analysis was conducted using data from 16 studies (from 14 publications) through three electronic databases (Google Scholar, PubMed, and Journal Storage) encompassing 7997 subjects. An overall EO prevalence was 2.1% (95% CI 1.1-3.0%, I2 = 93.75%). Subgroup analyses by continent and diagnostic methods were carried out. Asia exhibited the highest prevalence of EO at 3.8% (95% CI 0.3-7.5%, I2 = 96.83%), and X-ray yielded the highest prevalence of 0.7% (95% CI 0.5-8.9%, I2 = 0.00%) compared with other modalities. The small-study effect was indicated by asymmetric funnel plots (Egger's z = 4.78, p < 0.01; Begg's z = 2.30, p = 0.02). Understanding the prevalence and developmental aspects of EO is crucial for clinical practitioners' awareness of this anatomical variation.

Safety-Net Hospital Status Is Associated With Coronary Artery Bypass Grafting Outcomes at an Urban Academic Medical Center

INTRODUCTION

Socioeconomic disparities impact outcomes after cardiac surgery. At our institution, cardiac surgery cases from the safety-net, county funded hospital (CH), which primarily provides care for underserved patients, are performed at the affiliated university hospital. We aimed to investigate the association of socioeconomic factors and CH referral status with outcomes after coronary artery bypass grafting (CABG).

METHODS

The institutional Adult Cardiac Surgery database was queried for perioperative and demographic data from patients who underwent isolated CABG between January 2014 and June 2020. The primary outcome was major adverse cardiovascular event (MACE), a composite of postoperative myocardial infarction, stroke, or death. Secondary outcomes included individual complications. Chi-square, Wilcoxon rank-sum, and logistic regression analyses were used to compare differences between CH and non-CH cohorts.

RESULTS

We included 836 patients with 472 (56.5%) from CH. Compared to the non-CH cohort, CH patients were younger, more likely to be Hispanic, non-English speaking, and be completely uninsured or require state-specific financial assistance. CH patients were more likely to have a history of tobacco and drug use, liver disease, diabetes, prior myocardial infarction, and greater degrees of left main coronary and left anterior descending artery stenosis. CH cases were less likely to be elective. The incidence of MACE was significantly higher in the CH cohort (16.3% versus 8.2%, P = 0.001). There were no significant differences in 30-d mortality, home discharge, prolonged mechanical ventilation, bleeding, sepsis, pneumonia, new dialysis requirement, cardiac arrest, or multiorgan system failure between cohorts. CH patients were more likely to develop renal failure and less likely to develop atrial fibrillation. On multivariable analysis, CH status (odds ratio 2.39, 95% confidence interval 1.25-4.55, P = 0.008) was independently associated with MACE.

CONCLUSIONS

CH patients undergoing CABG presented with greater comorbidity burden, more frequently required nonelective surgery, and are at significantly higher risk of postoperative MACE.

Development of a Novel Hierarchically Biofabricated Blood Vessel Mimic Decorated with Three Vascular Cell Populations for the Reconstruction of Small-Diameter Arteries

The availability of grafts to replace small-diameter arteries remains an unmet clinical need. Here, the validated methodology is reported for a novel hybrid tissue-engineered vascular graft that aims to match the natural structure of small-size arteries. The blood vessel mimic (BVM) comprises an internal conduit of co-electrospun gelatin and polycaprolactone (PCL) nanofibers (corresponding to the tunica intima of an artery), reinforced by an additional layer of PCL aligned fibers (the internal elastic membrane). Endothelial cells are deposited onto the luminal surface using a rotative bioreactor. A bioprinting system extrudes two concentric cell-laden hydrogel layers containing respectively vascular smooth muscle cells and pericytes to create the tunica media and adventitia. The semi-automated cellularization process reduces the production and maturation time to 6 days. After the evaluation of mechanical properties, cellular viability, hemocompatibility, and suturability, the BVM is successfully implanted in the left pulmonary artery of swine. Here, the BVM showed good hemostatic properties, capability to withstand blood pressure, and patency at 5 weeks post-implantation. These promising data open a new avenue to developing an artery-like product for reconstructing small-diameter blood vessels.

Thirteen Years of Impactful, Minimally Invasive Coronary Surgery: Short- and Long-Term Results for Single and Multi-Vessel Disease

OBJECTIVES

Minimally invasive coronary surgery (MICS) via lateral thoracotomy is a less invasive alternative to the traditional median full sternotomy approach for coronary surgery. This study investigates its effectiveness for short- and long-term revascularization in cases of single and multi-vessel diseases.

METHODS

A thorough examination was performed on the databases of two cardiac surgery programs, focusing on patients who underwent minimally invasive coronary bypass grafting procedures between 2010 and 2023. The study involved patients who underwent either minimally invasive direct coronary artery bypass grafting (MIDCAB) for the revascularization of left anterior descending (LAD) artery stenosis or minimally invasive multi-vessel coronary artery bypass grafting (MICSCABG). Our assessment criteria included in-hospital mortality, long-term mortality, and freedom from reoperations due to failed aortocoronary bypass grafts post-surgery. Additionally, we evaluated significant in-hospital complications as secondary endpoints.

RESULTS

A total of 315 consecutive patients were identified between 2010 and 2023 (MIDCAB 271 vs. MICSCABG 44). Conversion to median sternotomy (MS) occurred in eight patients (2.5%). The 30-day all-cause mortality was 1.3% (n = 4). Postoperative AF was the most common complication postoperatively (n = 26, 8.5%). Five patients were reoperated for bleeding (1.6%), and myocardial infarction (MI) happened in four patients (1.3%). The mean follow-up time was six years (±4 years). All-cause mortality was 10.3% (n = 30), with only five (1.7%) patients having a confirmed cardiac cause. The reoperation rate due to graft failure or the progression of aortocoronary disease was 1.4% (n = 4).

CONCLUSIONS

Despite the complexity of the MICS approach, the results of our study support the safety and effectiveness of this procedure with low rates of mortality, morbidity, and conversion for both single and multi-vessel bypass surgeries. These results underscore further the necessity to implement such programs to benefit patients.

Coronary Artery Surgery: Past, Present, and Future

Coronary artery bypass grafting (CABG) is the most commonly performed and studied major cardiac operation worldwide. An understanding of the evolution of CABG, including the early days of cardiac surgery, the first bypass operation, continuous improvements in techniques, and streamlining of the operation, is important to inform current trends and future innovations. This article will examine how CABG evolved (from techniques to conduits), describe current trends in the field, and explore what lies on the horizon for the future of CABG.

Assessment of online information on robotic cardiac and thoracic surgery

Online health resources are important for patients seeking perioperative information on robotic cardiac and thoracic surgery. The value of the resources depends on their readability, accuracy, content, quality, and suitability for patient use. We systematically assess current online health information on robotic cardiac and thoracic surgery. Systematic online searches were performed to identify websites discussing robotic cardiac and thoracic surgery. For each website, readability was measured by nine standardized tests, and accuracy and content were assessed by an independent panel of two robotic cardiothoracic surgeons. Quality and suitability of websites were evaluated using the DISCERN and Suitability Assessment of Materials tools, respectively. A total of 220 websites (120 cardiac, and 100 thoracic) were evaluated. Both robotic cardiac and thoracic surgery websites were very difficult to read with mean readability scores of 13.8 and 14.0 (p = 0.97), respectively, requiring at least 13 years of education to be comprehended. Both robotic cardiac and thoracic surgery websites had similar accuracy, amount of content, quality, and suitability (p > 0.05). On multivariable regression, academic websites [Exp (B)], 2.25; 95% confidence interval [CI], 1.60-3.16; P < 0.001), and websites with higher amount of content [Exp (B)],1.73; 95% CI, 1.24-2.41; P < 0.001) were associated with higher accuracy. There was no association between readability of websites and accuracy [Exp (B)], 1.04; 95% CI, 0.90-1.21; P = 0.57). Online information on robotic cardiac and thoracic surgery websites overestimate patients' understanding and require at least 13 years of education to be comprehended. As website accuracy is not associated with ease of reading, the readability of online resources can be improved without compromising accuracy.

Non-pharmacological interventions to support coronary artery bypass graft (CABG) patient recovery following discharge: protocol for a scoping review

BACKGROUND

In Canada, approximately 15 000 people undergo coronary artery bypass grafting (CABG) each year. However, 9.5% of these patients are urgently readmitted to hospital within 30 days of surgery. Postoperative interventions following discharge play an important role in reducing readmissions and improving CABG patient outcomes. Therefore, it is important to determine effective interventions available to enhance CABG patient recovery following postoperative discharge.

OBJECTIVES

Our scoping review aims to identify non-pharmacological interventions available to support recovery of patients who are discharged after CABG in the community setting.

METHODS

The methodological framework described by Arksey and O'Malley will be applied to this review. Our search strategy will include electronic databases (Medline, Embase, Cochrane Library and CINAHL), and studies will be screened and reviewed by two independent reviewers. Studies looking at non-pharmacological interventions targeting patients who are discharged after CABG will be included. Preliminary searches were conducted March 2022 and following abstract screening, full-text screening was completed May 2023. Data extraction is planned to begin September 2023 with an expected finish date of October 2023. The study is expected to be completed by January 2024.

ETHICS AND DISSEMINATION

This scoping review will retrieve and analyse previously published studies in which informed consent was obtained by primary investigators. Therefore, no ethical review or approval will be required. This scoping review aims to enumerate available non-pharmacological interventions to support recovery of patients who are discharged after CABG and identify gaps in postoperative recovery after discharge to support the development of innovative and targeted interventions. On completion of this review, we will ensure broad dissemination of our findings through peer-reviewed, open-access journals, conference presentations and hold meetings to engage stakeholders, including clinicians, policy makers and others.

Zinc-aspirin preconditioning reduces endothelial damage of arterial grafts in a rodent model of revascularization

Introduction

Coronary artery bypass grafting (CABG) is the most common cardiac surgical procedure. The prognosis of revascularization via CABG is determined by the patency of the used grafts, for which an intact endothelium is essential. The degree of ischemia-reperfusion injury (IRI), which occurs during the harvest and implantation of the grafts, is an important determinant of graft patency. Preconditioning with aspirin, a nonsteroidal anti-inflammatory drug has been shown to reduce the functional and molecular damage of arterial grafts in a rodent model. Studies have found that the zinc-aspirin complex may be able to exert an even better protective effect in pathological cardiovascular conditions. Thus, our aim was to characterize the protective effect of zinc-aspirin complex on free arterial grafts in a rodent model of revascularization.

Methods

Donor Lewis rats were treated with either zinc-aspirin, aspirin, or placebo (n = 8) for 5 days, then the aortic arches were harvested and stored in cold preservation solution and implanted heterotopically in the abdominal cavity of the recipient rats, followed by 2 h of reperfusion. There was also a non-ischemia-reperfusion control group (n = 8). Functional measurements using organ bath and histomorphological changes using immunohistochemistry were analyzed.

Results

The endothelium dependent maximal vasorelaxation was improved (non-transplanted control group: 82% ± 3%, transplanted control group: 14% ± 2%, aspirin group: 31% ± 4%, zinc-aspirin group: 52% ± 4%), the nitro-oxidative stress and cell apoptosis decreased, and significant endothelial protection was shown in the groups preconditioned with aspirin or zinc-aspirin. However, zinc-aspirin proved to be more effective in the reduction of IRI, than aspirin alone.

Discussion

Preconditioning with zinc-aspirin could be a promising way to protect the function and structural integrity of free arterial grafts, thus improving the outcomes of CABG.

The efficacy of earplugs and eye masks for delirium severity and sleep quality in patients undergoing coronary artery bypass grafting in cardiac intensive care units: A single-blind, randomised controlled trial

BACKGROUND AND PURPOSE

Delirium is a neuropsychiatric syndrome with a wide range of possible causes and multiple complications in patients admitted to intensive care units. It is, therefore, necessary to seek appropriate and safe strategies to prevent and manage delirium. This study is intended to examine the efficacy of eye masks and earplugs for delirium severity and sleep quality in patients with coronary artery bypass grafting in a cardiac intensive care unit.

MATERIALS AND METHODS

This single-blind, randomised controlled trial was conducted on 114 patients who were consecutively enrolled and randomly assigned to either the experimental group or the control group. The experimental group received routine care plus eye masks and earplugs, and the control group received only routine care. The delirium severity and sleep quality were measured with the Neelon and Champagne confusion scale and the Verran and Snyder-Halpern sleep scale.

RESULTS

The mean delirium severity score differed significantly between the two groups on the second, third, and fourth postoperative days (p < 0.001). Although the trend of changes in the mean delirium severity score from the first postoperative day (before the intervention) to the second, third, and fourth postoperative days was downward in the two groups (trending towards higher delirium severity), the control group experienced greater changes than the experimental group. An intragroup analysis of delirium severity detected a statistically significant difference in both the experimental and control groups (p < 0.001). The sleep quality domains (sleep disturbance, sleep effectiveness, sleep supplementation) showed a statistically significant difference between the two groups across the three intervention days (p < 0.001).

CONCLUSION

The overnight use of eye masks and earplugs were found to have positive effects on sleep quality domains (sleep disturbance, sleep effectiveness, sleep supplementation) and delirium severity in coronary artery bypass grafting patients admitted to the cardiac intensive care unit for several days. It was also found that a significant interaction effect between the sleep disturbance subscale and delirium severity exists.

CLINICAL TRIAL REGISTRATION NUMBER

(https://en.irct.ir): IRCT20210523051370N2.

Genomic insights into heart health: Exploring the genetic basis of cardiovascular disease

Cardiovascular diseases (CVDs) are considered as the leading cause of death worldwide. CVD continues to be a major cause of death and morbidity despite significant improvements in its detection and treatment. Therefore, it is strategically important to be able to precisely characterize an individual's sensitivity to certain illnesses. The discovery of genes linked to cardiovascular illnesses has benefited from linkage analysis and genome-wide association research. The last 20 years have seen significant advancements in the field of molecular genetics, particularly with the development of new tools like genome-wide association studies. In this article we explore the profound impact of genetic variations on disease development, prognosis, and therapeutic responses. And the significance of genetics in cardiovascular risk assessment and the ever-evolving realm of genetic testing, offering insights into the potential for personalized medicine in this domain. Embracing the future of cardiovascular care, the article explores the implications of pharmacogenomics for tailored treatments, the promise of emerging technologies in cardiovascular genetics and therapies, including the transformative influence of nanotechnology. Furthermore, it delves into the exciting frontiers of gene editing, such as CRISPR/Cas9, as a novel approach to combat cardiovascular diseases. And also explore the potential of stem cell therapy and regenerative medicine, providing a holistic view of the dynamic landscape of cardiovascular genomics and its transformative potential for the field of cardiovascular medicine.

Exertional angina after cardiac bypass surgery successfully solved by endovascular occlusion of unligated lateral costal artery

The internal mammary artery has become the primary conduit for the surgical revascularisation of the left anterior descending artery. Large side branches of internal mammary artery are typically ligated during cardiac surgery to avoid a potential coronary steal phenomenon. However, ligation of side branches can be unsuccessful due to the technically difficult surgical exploration of internal mammary artery branches. In this article, we present a case of a man who suffered from exertion angina pectoris despite successful surgical revascularisation of occluded left anterior descending artery by the internal mammary artery bypass. The coronary steal syndrome caused by the mighty side branch of internal mammary artery, that is, lateral costal artery was concluded as the reason of exertional angina. The endovascular procedure was performed and the lateral costal artery was successfully occluded using vascular plug. The occlusion of lateral costal artery has led to a complete disappearance of the exertional angina.

Coronary Artery Bypass Surgery: Evidence-Based Practice

Coronary artery bypass graft (CABG) surgery remains a pivotal cornerstone, offering established symptomatic alleviation and prognostic advantages for patients grappling with complex multivessel and left main coronary artery diseases. Despite the lucid guidance laid out by contemporary guidelines regarding the choice between CABG and percutaneous coronary intervention (PCI), a notable hesitation persists among certain patients, characterized by psychological reservations, knowledge gaps, or individual beliefs that sway their inclination toward surgical intervention. This comprehensive review critically synthesizes the prevailing guidelines, modern practices, and outcomes pertaining to CABG surgery, delving into an array of techniques and advancements poised to enhance both short-term and enduring surgical outcomes. The exploration encompasses advances in on-pump and off-pump procedures, conduit selection strategies encompassing the bilateral utilization of internal mammary artery and radial artery conduits, meticulous graft evaluation methodologies, and the panorama of minimally invasive approaches, including those assisted by robotic technology. Furthermore, the review navigates the terrain of hybrid coronary revascularization, shedding light on the pivotal roles of shared decision-making and the heart team in shaping treatment pathways. As a comprehensive compendium, this review not only navigates the intricate landscape of CABG surgery but also aligns it with contemporary practices, envisioning its trajectory within the evolving currents of healthcare dynamics.

Surgical Strategy for Sternal Closure in Patients with Surgical Myocardial Revascularization Using Mammary Arteries

BACKGROUND

Coronary artery bypass grafting has evolved from all venous grafts to bilateral mammary artery (BIMA) grafting. This was possible due to the long-term patency of the left and right internal mammary demonstrated in angiography studies compared to venous grafts. However, despite higher survival rates when using bilateral mammary arteries, multiple studies report a higher rate of surgical site infections, most notably deep sternal wound infections, a so-called "never event".

METHODS

We designed a prospective study between 1 January 2022 and 31 December 2022 and included all patients proposed for total arterial myocardial revascularization in order to investigate the rate of surgical site infections (SSI). Chest closure in all patients was performed using a three-step protocol. The first step refers to sternal closure. If the patient's BMI is below 35 kg/m2, sternal closure is achieved using the "butterfly" technique with standard steel wires. If the patient's BMI exceeds 35 kg/m2, we use nitinol clips or hybrid wire cable ties according to the surgeon's preference for sternal closure. The main advantages of these systems are a larger implant-to-bone contact with a reduced risk of bone fracture. The second step refers to presternal fat closure with two resorbable monofilament sutures in a way that the edges of the skin perfectly align at the end. The third step is skin closure combined with negative pressure wound therapy.

RESULTS

This system was applied to 217 patients. A total of 197 patients had bilateral mammary artery grafts. We report only 13 (5.9%) superficial SSI and only one (0.46%) deep SSI. The preoperative risk of major wound infection was 3.9 +/- 2.7. Bilateral mammary artery grafting was not associated with surgical site infection in a univariate analysis.

CONCLUSIONS

We believe this strategy of sternal wound closure can reduce the incidence of deep surgical site infection when two mammary arteries are used in coronary artery bypass surgery.

Alterations to Kidney Physiology during Cardiopulmonary Bypass-A Narrative Review of the Literature and Practical Remarks

INTRODUCTION

According to different authors, cardiac surgery-associated acute kidney injury (CSA-AKI) incidence can be as high as 20-50%. This complication increases postoperative morbidity and mortality and impairs long-term kidney function in some patients. This review aims to summarize current knowledge regarding alterations to renal physiology during cardiopulmonary bypass (CPB) and to discuss possible nephroprotective strategies for cardiac surgeries. Relevant sections: Systemic and renal circulation, Vasoactive drugs, Fluid balance and Osmotic regulation and Inflammatory response.

CONCLUSIONS

Considering the available scientific evidence, it is concluded that adequate kidney perfusion and fluid balance are the most critical factors determining postoperative kidney function. By adequate perfusion, one should understand perfusion with proper oxygen delivery and sufficient perfusion pressure. Maintaining the fluid balance is imperative for a normal kidney filtration process, which is essential for preserving the intra- and postoperative kidney function.

FUTURE DIRECTIONS

The review of the available literature regarding kidney function during cardiac surgery revealed a need for a more holistic approach to this subject.

Is pre-operative monocyte count-high-density lipoprotein ratio associated with postoperative acute kidney injury in isolated coronary artery bypass grafting?

OBJECTIVE

Monocyte-to-high-density lipoprotein cholesterol ratio has emerged as an indicator of inflammation and oxidative stress in recent years. The aim of this study was to evaluate the association of monocyte-to-high-density lipoprotein ratio with postoperative acute kidney injury in isolated coronary artery bypass grafting.

METHODS

A total of 954 patients (672 males, mean age 60.8 ± 8.2 years), operated on between June 2014 and June 2022, at the same centre by the same team, for isolated coronary artery bypass grafting with cardiopulmonary bypass, whose preoperative serum creatinine level was < 1.5 mg/dl, were enrolled in the study. Patients were placed in group 1 if they had acute kidney injury in the early postoperative period (n = 161) and group 2 comprised those without (n = 793). Univariate and subsequent multivariate logistic regression analysis were done to determine significant clinical factors, and independent predictors of acute kidney injury.

RESULTS

Pre-operative monocyte count (p = 0.0001), monocyte count-high-density lipoprotein cholesterol ratio (p = 0.0001), C-reactive protein (p = 0.0001), erythrocyte sedimentation rate (p = 0.0001), mean platelet volume (p = 0.0001) and postoperative first- and third-day C-reactive protein levels (p = 0.0001) were significantly increased in group 1. Multivariate logistic regression analysis revealed that pre-operative elevated monocyte count (p = 0.0001), monocyte-high-density lipoprotein ratio (p = 0.0001), erythrocyte sedimentation rate (p = 0.0001), postoperative first-day C-reactive protein level (p = 0.0001), postoperative first-third day erythrocyte sedimentation rate (p = 0.002, p = 0.004, respectively) and mean platelet volume (p = 0.02, p = 0.0001, respectively) were independent predictors of early postoperative acute kidney injury in patients who had undergone isolated coronary artery bypass grafting.

CONCLUSIONS

Pre-operative monocyte-high-density lipoprotein cholesterol ratio was found to be an independent predictor of acute kidney injury in the early postoperative period of isolated coronary artery bypass grafting.

Effects of blood transfusion, cardiopulmonary bypass time, and bypassed vessels on mortality following isolated and combined coronary artery bypass grafting

OBJECTIVE

This study aimed to investigate the correlation between the number of bypassed vessels, the duration of Cardiopulmonary bypass, blood transfusion requirements, revision rates, and mortality outcomes. The objective was to get insights into the potential challenges that may arise during the postoperative phase.

METHODS

Our study covered a total of 677 patients from January 2015 to January 2021. The study and analysis focused on many factors including the surgical procedure, the number of bypassed vessels, transfusion requirements, comorbidities, revision rates, the administration of blood thinners, and early mortality.

RESULTS

Male patients numbered 513 and female patients 164. The combined coronary artery bypass grafting surgeries were 187, whereas the isolated ones were 490. Combination procedures traditionally used one- and two-vessel bypass grafting. 30.9% of patients had three vessels, while 31.6% had four. The typical blood transfusion has 4.2 erythrocytes. Fresh frozen plasma averaged 2.9 units, platelets 2.4 units, and whole fresh blood 2.6 units. The average cardiopulmonary bypass time was 145.1 and cross-clamp time was 89.3.

CONCLUSION

Six vessel bypasses have the highest revision rate. Transfusion rises with longer cardiopulmonary bypass and cross-clamp periods. Using acetylsalicylic acid before surgery increases the need for fresh frozen plasma and platelets. However, warfarin sodium increases the need for fresh frozen plasma and increases mortality. The revision highly linked with total CPB, cross-clamp times, all blood transfusions, and mortality.

Multi-Omics Profiling of Human Endothelial Cells from the Coronary Artery and Internal Thoracic Artery Reveals Molecular but Not Functional Heterogeneity

Major adverse cardiovascular events occurring upon coronary artery bypass graft surgery are typically accompanied by endothelial dysfunction. Total arterial revascularisation, which employs both left and right internal thoracic arteries instead of the saphenous vein to create a bypass, is associated with better mid- and long-term outcomes. We suggested that molecular profiles of human coronary artery endothelial cells (HCAECs) and human internal mammary artery endothelial cells (HITAECs) are coherent in terms of transcriptomic and proteomic signatures, which were then investigated by RNA sequencing and ultra-high performance liquid chromatography-mass spectrometry, respectively. Both HCAECs and HITAECs overexpressed molecules responsible for the synthesis of extracellular matrix (ECM) components, basement membrane assembly, cell-ECM adhesion, organisation of intercellular junctions, and secretion of extracellular vesicles. HCAECs were characterised by higher enrichment with molecular signatures of basement membrane construction, collagen biosynthesis and folding, and formation of intercellular junctions, whilst HITAECs were notable for augmented pro-inflammatory signaling, intensive synthesis of proteins and nitrogen compounds, and enhanced ribosome biogenesis. Despite HCAECs and HITAECs showing a certain degree of molecular heterogeneity, no specific markers at the protein level have been identified. Coherence of differentially expressed molecular categories in HCAECs and HITAECs suggests synergistic interactions between these ECs in a bypass surgery scenario.

Systematic review and meta-analysis of the treatment strategies for coronary artery bypass graft patients with concomitant carotid artery atherosclerotic disease

OBJECTIVE

Stroke is one of the devastating complications after coronary artery bypass graft (CABG). Underlying carotid artery atherosclerotic disease is reported to be an independent risk factor. The optimal treatment strategy for these patients remains under debate.

METHODS

We aimed to perform a network meta-analysis to evaluate the safety and efficacy of additional carotid interventions for patients with concomitant carotid artery atherosclerotic disease who require CABG by comparing perioperative adverse event rates. All articles through February 2022 were searched using MEDLINE and EMBASE to identify studies that investigated outcomes of CABG only as well as additional staged vs combined carotid interventions by both carotid endarterectomy (CEA) and carotid artery stenting (CAS).

RESULTS

Two randomized controlled trials and 23 observational studies were included, yielding a total of 32,473 patients who underwent combined CEA and CABG (n = 20,204), CEA and staged CABG (n = 6882), CABG and staged CEA (n = 340), CAS and CABG regardless of timing and sequences (n = 1224), and CABG only (n = 3823). No strategy showed a significant advantage over CABG only in all perioperative outcomes. CEA and staged CABG was associated with the lowest perioperative stroke/transient ischemic attack (TIA) rate, significantly lower compared with CAS and CABG (odds ratio [OR], 0.52; 95% confidence interval [CI], 0.36-0.76) as well as CABG and staged CEA (OR, 0.41; 95% CI, 0.23-0.74), but was also associated with the highest perioperative mortality (OR, 2.50; 95% CI, 1.67-3.85, vs CAS and CABG) and myocardial infarction rate (OR, 3.70 [95% CI, 1.16-12.5] and OR, 2.50 [95% CI, 1.35-4.55] vs CAS and CABG, vs combined CEA and CABG, respectively).

CONCLUSIONS

CEA and staged CABG are associated with low perioperative stroke/transient ischemic attack rates with a tradeoff of higher mortality and myocardial infarction rate. No strategy showed a significant advantage over the CABG-only strategy in all perioperative outcomes, outlining the importance of a tailored approach and determining proper indications for carotid intervention in these patients.

Acute protein kinase C beta inhibition preserves coronary endothelial function after cardioplegic hypoxia/reoxygenation

Objective

Protein kinase C (PKC) influences myocardial contractility and susceptibility to long-term cardiac dysfunction after ischemia-reperfusion injury. In diabetes, PKC inhibition has a protective effect in terms of microvascular dysfunction. SK-channel dysfunction also influences endothelial dysfunction in cardioplegic hypoxia-reoxygenation (CP-H/R). Here, we examine whether acute inhibition of PKC beta protects against CP-H/R-induced coronary endothelial and SK channel dysfunction.

Methods

Isolated mouse coronary arterioles, half pretreated with selective PKC inhibitor ruboxistaurin (RBX), were subjected to hyperkalemic, cardioplegic hypoxia (1 hour), and reoxygenation (1 hour) with Krebs buffer. Sham control vessels were continuously perfused with oxygenated Krebs buffer without CP-H/R. After 1 hour of reoxygenation, responses to the endothelium-dependent vasodilator adenosine-diphosphate (ADP) and the SK-channel activator NS309 were examined. Endothelial SK-specific potassium currents from mouse heart endothelial cells were examined using whole-cell path clamp configurations in response to NS309 and SK channel blockers apamin and TRAM34.

Results

CP-H/R significantly decreased coronary relaxation responses to ADP (P = .006) and NS309 (P = .0001) compared with the sham control group. Treatment with selective PKC beta inhibitor RBX significantly increased recovery of coronary relaxation responses to ADP (P = .031) and NS309 (P = .004) after CP-H/R. Treatment with RBX significantly increased NS309-mediated potassium currents following CP-H/R (P = .0415). Apamin and TRAM34 sensitive currents were significantly greater in CP-H/R + RBX versus CP-H/R mouse heart endothelial cells (P = .0027).

Conclusions

Acute inhibition of PKC beta significantly protected mouse coronary endothelial function after CP-H/R injury. This suggests that acute PKC beta inhibition may be a novel approach for preventing microvascular dysfunction during CP-H/R.

The association of body composition assessment with hospital length of stay in off-pump coronary artery bypass patients

Introduction

Bioelectrical impedance analysis is a widely available, non-invasive method for body composition assessment.

Aim

To elucidate the perioperative body composition alterations and their prognostic utility for hospital length of stay (LOS) in low risk, off-pump coronary artery bypass (OPCAB) patients.

Material and methods

Fifty patients undergoing elective OPCAB were included in the study. Body composition assessments were performed 1 day before the scheduled surgery and on the 6th postoperative day. Patients were grouped into < 9 days (n = 29, 58%) and ≥ 9 days (n = 21, 42%). Multivariate logistic regression analysis was performed to create a body composition-based screening panel for prolonged hospital stay.

Results

No significant differences in anthropometric measurements, clinical characteristics or occurrence of postoperative complications were detected between the study groups. Patients with longer hospitalization had significantly higher content of fat mass (FM%) and fat mass index (FMI), and significantly lower content of fat free mass (FFM%) baseline parameters (p = 0.011, p = 0.04 and p = 0.012, respectively). High FM% values had 15-fold, low FFM% values had 13-fold and high FMI values had 7-fold higher risk of experiencing longer stay in the hospital (p = 0.001, p = 0.001 and p = 0.005, respectively). The combined panel of three variables (higher FM%, lower FFM% and higher FMI) had 16-fold higher risk of longer hospitalization (adjusted OR = 16.40; 95% CI: 3.52-76.34; p = 0.0004).

Conclusions

Preoperative high FM and low FFM content are independent predictors of prolonged hospital length of stay in normal- and increased-BMI patients after OPCAB.

The Quality of Coronary Artery Bypass Grafting Videos on YouTube

Objective  YouTube (YouTube LLC, San Bruno, California, United States), one of the most accessed sites on the internet, has become a widespread source of healthcare information for patients. Videos about coronary artery bypass grafts (CABG) have accrued tens of millions of views on the platform, yet their educational quality is unknown. This study investigates the educational landscape of videos regarding CABG procedures on YouTube. Methods YouTube was queried for "Coronary Artery Bypass Graft Surgery" and "Coronary Artery Bypass Graft Procedure". After applying exclusion criteria, 73 videos were assessed. Two independent reviewers rated the material with the Global Quality Scale (GQS) (5 = high quality, 0 = low quality) to judge educational value. A ratio of view count to days since upload was applied to assess video popularity. Source, modality, and date of upload were recorded for each video as well. Results An average GQS score of 2.94 was found, indicating poor educational quality of the 73 YouTube videos on CABG procedures. Videos uploaded by physicians (56/73; 76.7%) had a significantly higher average GQS score than those uploaded by non-physicians (p<0.001). When content was grouped by delivery method, physician-led presentations (24/73 or 32.9%) produced the highest average GQS score of 3.35; conversely, patient-friendly delivery methods (18/73 or 24.7%) yielded the lowest average GQS score of 2.36 (p<0.001). Neither the view ratio nor the days since upload significantly correlated with the educational quality of the video. Conclusion Although CABG videos are readily available on YouTube, they often contain considerable biases and misleading information. With online sources for healthcare education now commonplace, physicians must be aware of the vast quantities of low-quality videos patients often encounter when weighing different treatment options. Further analysis of CABG videos on YouTube may allow physicians to ameliorate this gap by producing videos that are not only high quality but highly viewed on the platform.

Minimal-Access Coronary Revascularization: Past, Present, and Future

Minimal-access cardiac surgery appears to be the future. It is increasingly desired by cardiologists and demanded by patients who perceive superiority. Minimal-access coronary artery revascularisation has been increasingly adopted throughout the world. Here, we review the history of minimal-access coronary revascularization and see that it is almost as old as the history of cardiac surgery. Modern minimal-access coronary revascularization takes a variety of forms-namely minimal-access direct coronary artery bypass grafting (MIDCAB), hybrid coronary revascularisation (HCR), and totally endoscopic coronary artery bypass grafting (TECAB). It is noteworthy that there is significant variation in the nomenclature and approaches for minimal-access coronary surgery, and this truly presents a challenge for comparing the different methods. However, these approaches are increasing in frequency, and proponents demonstrate clear advantages for their patients. The challenge that remains, as for all areas of surgery, is demonstrating the superiority of these techniques over tried and tested open techniques, which is very difficult. There is a paucity of randomised controlled trials to help answer this question, and the future of minimal-access coronary revascularisation, to some extent, is dependent on such trials. Thankfully, some are underway, and the results are eagerly anticipated.