Acute kidney injury in renal transplant recipients undergoing cardiac surgery.

BACKGROUND: Acute kidney injury (AKI) is a key risk factor for chronic kidney disease in the general population, but has not been investigated in detail among renal transplant recipients (RTRs). We investigated the incidence, severity and risk factors for AKI following cardiac surgery among RTRs compared with non-RTRs with otherwise similar clinical characteristics. METHODS: We conducted a retrospective cohort study of RTRs (n = 83) and non-RTRs (n = 83) who underwent cardiac surgery at two major academic medical centers. Non-RTRs were matched 1:1 to RTRs by age, preoperative (preop) estimated glomerular filtration rate and type of cardiac surgery. We defined AKI according to Kidney Disease: Improving Global Outcomes criteria. RESULTS: RTRs had a higher rate of AKI following cardiac surgery compared with non-RTRs [46% versus 28%; adjusted odds ratio 2.77 (95% confidence interval 1.36-5.64)]. Among RTRs, deceased donor (DD) versus living donor (LD) status, as well as higher versus lower preop calcineurin inhibitor (CNI) trough levels, were associated with higher rates of AKI (57% versus 33% among DD-RTRs versus LD-RTRs; P = 0.047; 73% versus 36% among RTRs with higher versus lower CNI trough levels, P = 0.02). The combination of both risk factors (DD status and higher CNI trough level) had an additive effect (88% AKI incidence among patients with both risk factors versus 25% incidence among RTRs with neither risk factor, P = 0.004). CONCLUSIONS: RTRs have a higher risk of AKI following cardiac surgery compared with non-RTRs with otherwise similar characteristics. Among RTRs, DD-RTRs and those with higher preop CNI trough levels are at the highest risk.

Fibroblast Growth Factor 23 Levels Associate with AKI and Death in Critical Illness.

Elevated plasma levels of the osteocyte-derived hormone fibroblast growth factor 23 (FGF23) have emerged as a powerful biomarker of cardiovascular disease and death in patients with CKD. Whether elevated urinary or plasma FGF23 levels are prospectively associated with AKI and death in critically ill patients is unknown. We therefore conducted a prospective cohort study of 350 critically ill patients admitted to intensive care units at an academic medical center to investigate whether higher urinary FGF23 levels associate with the composite end point of AKI or in-hospital mortality (AKI/death). We measured urinary FGF23 levels within 24 hours of admission to the intensive care unit. In a subcohort (n=131) we also measured plasma levels of FGF23, calcium, phosphate, parathyroid hormone, and vitamin D metabolites. Urinary and plasma FGF23 levels, but not other mineral metabolites, significantly associated with AKI/death. In multivariate analyses, patients in the highest compared with the lowest quartile of urinary FGF23 had a 3.9 greater odds (95% confidence interval, 1.6 to 9.5) of AKI/death. Higher urinary FGF23 levels also independently associated with greater hospital, 90-day, and 1-year mortality; longer length of stay; and several other important adverse outcomes. In conclusion, elevated FGF23 levels measured in the urine or plasma may be a promising novel biomarker of AKI, death, and other adverse outcomes in critically ill patients.

Determinants of the postpericardiotomy syndrome: a systematic review.

BACKGROUND: Postpericardiotomy syndrome (PPS) is a common complication following cardiac surgery; however, the exact pathogenesis remains uncertain. Identifying risk factors of PPS might help to better understand the syndrome. The aim of this study was to provide an overview of existing literature around determinants of PPS in adult cardiac surgery patients. MATERIAL AND METHODS: Two independent investigators performed a systematic search in MEDLINE, EMBASE and the Cochrane Central Register. The search aimed to identify studies published between January 1950 and December 2015, in which determinants of PPS were reported. RESULTS: A total of 19 studies met the selection criteria. In these studies, 14 different definitions of PPS were used. The median incidence of PPS was 16%. After quality assessment, seven studies were considered eligible for this review. Lower preoperative interleukin-8 levels and higher postoperative complement conversion products were associated with a higher risk of PPS. Among other clinical factors, a lower age, transfusion of red blood cells and lower preoperative platelet and haemoglobin levels were associated with a higher risk of PPS. Colchicine use decreased the risk of PPS. CONCLUSION: We found that both the inflammatory response and perioperative bleeding and coagulation may play a role in the development of PPS, suggesting a multifactorial aetiology of the syndrome. Due to a lack of a uniform definition of PPS in the past, study comparability was poor across the studies.

Intraoperative High-Dose Dexamethasone and Severe AKI after Cardiac Surgery.

Administration of prophylactic glucocorticoids has been suggested as a strategy to reduce postoperative AKI and other adverse events after cardiac surgery requiring cardiopulmonary bypass. In this post hoc analysis of a large placebo-controlled randomized trial of dexamethasone in 4465 adult patients undergoing cardiac surgery, we examined severe AKI, defined as use of RRT, as a primary outcome. Secondary outcomes were doubling of serum creatinine level or AKI-RRT, as well as AKI-RRT or in-hospital mortality (RRT/death). The primary outcome occurred in ten patients (0.4%) in the dexamethasone group and in 23 patients (1.0%) in the placebo group (relative risk, 0.44; 95% confidence interval, 0.19 to 0.96). In stratified analyses, the strongest signal for potential benefit of dexamethasone was in patients with an eGFR<15 ml/min per 1.73 m(2). In conclusion, compared with placebo, intraoperative dexamethasone appeared to reduce the incidence of severe AKI after cardiac surgery in those with advanced CKD.

Dexamethasone for the prevention of postpericardiotomy syndrome: A DExamethasone for Cardiac Surgery substudy.

BACKGROUND: The postpericardiotomy syndrome (PPS) is a common complication following cardiac surgery. The pathophysiology remains unclear, although evidence exists that surgical trauma and the use of cardiopulmonary bypass provoke an immune response leading to PPS. We hypothesized that an intraoperative dose of dexamethasone decreases the risk of PPS, by reducing this inflammatory response. METHODS: We performed a subanalysis of the DECS study, which is a multicenter, double-blind, placebo-controlled, randomized trial of 4,494 patients undergoing cardiac surgery with use of cardiopulmonary bypass. The aim of the DECS study was to investigate whether a single intraoperative dose of 1 mg/kg dexamethasone reduced the incidence of a composite of death, myocardial infarction, stroke, renal failure, or respiratory failure, within 30 days of randomization. In this substudy, we retrospectively analyzed the occurrence of PPS in 822 patients who were included in the DECS trial and underwent valvular surgery. Postpericardiotomy syndrome was diagnosed if 2 of 5 listed symptoms were present: unexplained fever, pleuritic chest pain, pericardial or pleural rub, new or worsening pericardial or pleural effusion. All medical charts, x-rays, and echocardiograms were reviewed. Secondary end point was the occurrence of complicated PPS, defined as PPS with need for evacuation of pleural effusion, pericardiocentesis, and tamponade requiring intervention or hospital readmission for PPS. This is a blinded, single-center, post hoc analysis. RESULTS: Postpericardiotomy syndrome occurred in 119 patients (14.5%). The incidence of PPS after dexamethasone compared with placebo was 13.5% vs 15.5% (relative risk 0.88, 95% CI 0.63-1.22). For complicated PPS, the incidence was 3.8% versus 3.2% (relative risk 1.17, 95% CI 0.57-2.41, P = .66), respectively. CONCLUSION: In patients undergoing valvular cardiac surgery, high-dose dexamethasone treatment had no protective effect on the occurrence of PPS or complicated PPS.

Inflammation in new-onset atrial fibrillation after cardiac surgery: a systematic review.

BACKGROUND: Postoperative new-onset atrial fibrillation (PNAF) is the most common complication following cardiac surgery. The pathogenesis of PNAF is multifactorial. The concept of the postoperative inflammatory response, as a potential underlying mechanism has been extensively studied. This review aims to provide a comprehensive summary of literature relevant to the association between the inflammatory response following cardiac surgery and PNAF. DESIGN: MEDLINE, EMBASE and the Cochrane Central Register were systematically reviewed by two independent investigators for studies published between January 1980 and May 2012, in which an association between serum markers of inflammation and PNAF was evaluated, or the effect of drugs with anti-inflammatory properties on the risk of PNAF. RESULTS: Sixty-three studies met selection criteria (39 observational and 24 randomized studies) including 27,363 patients. The mean incidence of PNAF after cardiac surgery was 25·5%. Elevated levels of various inflammatory mediators were associated with PNAF, and the most consistent association was found between white blood cell count and PNAF. Of the drugs with anti-inflammatory properties, statins gave the best protective effect against PNAF, followed by anti-oxidants, steroids and colchicine. Nonsteroidal anti-inflammatory drugs did not prevent PNAF significantly. CONCLUSION: The postoperative inflammation response may play a role in the pathogenesis of PNAF. However, of the inflammation biomarkers, only elevated white blood cell count reliably predicts PNAF. Pre- and perioperative use of statins and several other drugs with anti-inflammatory properties reduce the incidence of PNAF.

Medium and long-term patency results of distal anastomosis connectors: a meta-analysis.

Background: The difficulty of suturing perfect anastomoses in limited-access conditions prevents the transition of traditional coronary artery bypass grafting (CABG) to sternal-sparing approaches, even in the robotic era. Automated coronary anastomotic connector technologies may address these difficulties, but to date, none have achieved broad adoption. Besides versatility, ease-of-use and cost-effectiveness, the key performance parameter of such technology is anastomotic patency. In this meta-analysis, we aim to evaluate published connector devices by examining their patency outcomes in distal anastomoses. Methods: The literature was systematically searched for studies comparing the angiographic patency of connector constructed coronary anastomoses to handsewn (HS) connections in adult patients undergoing CABG. The primary outcome was anastomosis patency across early (<30 days), mid-term (30 days to 1 year) and long-term (>1 year) follow-up. Random-effects meta-analyses were employed to analyze and compare patency using pooled risk ratios (RR) with 95% confidence intervals (CI). Results: The search yielded 14 studies concerning eight connector devices. In 4,311 patients, a total of 4,328 anastomoses were constructed, 674 with connector devices and 3,654 with a HS technique. The pooled device patency over all timeframes was non-inferior to the HS technique (RR 0.90, 95% CI: 0.56-1.44). Technologies having a relatively large blood-exposed non-intimal surface area (BENIS, >15 mm2) performed acceptably when applied to large target vessels [>2.0-2.5 mm inner diameter (ID)]. A tiny anastomotic orifice area (AOA, < ca. 4 mm2) appeared to adversely affect results. Technologies realizing a generous AOA in combination with a limited BENIS showed superior results and applicability by performing well across the entire range of target coronary artery diameters (>1.0-1.5 mm ID). Conclusions: The overall results suggest that connectors yield at least non-inferior anastomosis patency outcomes compared to HS techniques in all observed timeframes. Optimizing device characteristics like BENIS and AOA appear fundamental for broad applicability.

A Nationwide Study of Clinical Outcomes After Robot-Assisted Coronary Artery Bypass Surgery and Hybrid Revascularization in the Netherlands.

OBJECTIVE: Robot-assisted minimally invasive direct coronary artery bypass (RA-MIDCAB) surgery and hybrid coronary revascularization (HCR) are minimally invasive alternative strategies to conventional coronary artery bypass surgery in patients with isolated left anterior descending (LAD) stenosis or multivessel coronary disease. We analyzed a large, multicenter data-set based on the Netherlands Heart Registration including all patients undergoing RA-MIDCAB. METHODS: We included 440 consecutive patients who underwent RA-MIDCAB with the left internal thoracic artery to LAD between January 2016 and December 2020. A proportion of patients underwent percutaneous coronary intervention (PCI) of non-LAD vessels (i.e., HCR). The primary outcome was all-cause mortality at median follow-up of 1 year, which was subdivided into cardiac and noncardiac. Secondary outcomes included target vessel revascularization (TVR) at median follow-up as well as 30-day mortality, perioperative myocardial infarction, reoperation for bleeding or anastomosis-related problems, and in-hospital ischemic cerebrovascular accident (iCVA). RESULTS: Among all patients, 91 (21%) underwent HCR. At median (IQR) follow-up of 19 (8 to 28) months, 11 patients (2.5%) had died. In 7 patients, the cause of death was defined as cardiac. TVR occurred in 25 patients (5.7%), of whom 4 underwent CABG and 21 underwent PCI. At 30-day follow-up, 6 patients (1.4%) had a perioperative myocardial infarction, of whom 1 died. One patient (0.2%) developed an iCVA, and 18 patients (4.1%) underwent reoperation for bleeding or anastomosis-related problems. CONCLUSIONS: The clinical outcomes of patients undergoing RA-MIDCAB or HCR in the Netherlands are good and promising when compared with the currently available literature.

Minimally invasive surgery or stenting for left anterior descending artery disease - meta-analysis.

Minimally invasive direct coronary artery bypass (MIDCAB) surgery and percutaneous coronary intervention (PCI) are both well-established minimally invasive revascularization strategies in patients with proximal left anterior descending (LAD) lesions. We aimed to evaluate the 20-years' experience by performing a systematic review and meta-analysis comparing MIDCAB versus PCI in adults with proximal LAD disease. We searched MEDLINE, EMBASE and Cochrane on October 1st, 2021 for articles published in the year 2000 or later. The primary outcome was all-cause mortality. Secondary outcomes included cardiac mortality, repeat target vessel revascularization (rTVR), myocardial infarction (MI), and cerebrovascular accident (CVA). Outcomes were analysed at short-term, mid-term, and long-term follow-up. Random effects meta-analyses were performed. Events were compared using risk ratios (RR) with 95% confidence intervals (CI). Our search yielded 17 studies pooling 3847 patients. At short-term follow-up, cardiac mortality was higher with MIDCAB than with PCI (RR 7.30, 95% CI: 1.38 to 38.61). At long-term follow-up, MIDCAB showed a decrease in all-cause mortality (RR 0.66, 95% CI: 0.46 to 0.93). MIDCAB showed a decrease in rTVR at mid-term follow-up (RR 0.16, 95% CI: 0.11 to 0.23) and at long-term follow-up (RR 0.25, 95% CI: 0.17 to 0.38). MI and CVA comparisons were not significant. In conclusion, in patients with proximal LAD lesions, MIDCAB showed a higher short-term mortality in the RCTs, but the cohort studies suggested a lower all-cause mortality at long-term follow-up. We confirm a decreased rTVR at mid-term follow-up in the RCTs and long-term follow-up in the cohort studies.

Basic principles of cardiothoracic surgery training: a position paper by the European Association for Cardiothoracic Surgery Residents Committee.

OBJECTIVES: Across Europe there are significant variations in the fundamental structure and content of cardiothoracic surgery (CTS) training programmes. Previous efforts have been made to introduce a Unified European Training System, which outlined the fundamentals of the ideal programme and supported a paradigm shift from an apprenticeship to a competency-based model. This article's goal was to define key structural, administrative and executive details of such a programme to lay the foundations for the standardization of cardiothoracic surgical training across Europe. METHODS: The European Association for Cardiothoracic Surgery Residents Committee had previously conducted a residents' training survey across Europe in 2020. Training curricula from the twelve most represented countries across Europe were either searched online or obtained from the countries' national trainee representative and reviewed by the committee. Information was collated and placed into one of the following categories to develop the position paper: (i) selection of eligible candidates, (ii) guidance for an outcome-based syllabus, (iii) documentation and evaluation of training progress, (iv) mandatory rotations and training courses, (v) number of independent or assisted cases and (vi) requirements and quality assurance of teachers. RESULTS: An independent professional body should promote an outcome-based syllabus and take responsibility for the training programme's quality assurance. Trainees should be selected on merit by an open and transparent process. Training should be delivered within a defined period and supervised by an appointed training committee to ensure its implementation. This committee should review the trainees progression regularly, provide feedback and offer trainees the opportunity to experience various training environments and trainers. A common electronic portal be used by trainees to record their agreed objectives and to evidence their completion. Trainees should regularly attend specialty-relevant courses and conferences to promote professional and academic development. The end of training is reached when the formal requirements of the training programme are met and the trainee is able to perform at the level expected of a day-1 independent surgeon. CONCLUSIONS: This article defines the key structural, administrative, and executive principles for CTS training. Programmes are encouraged to review and modify their training curricula, if necessary, to ensure the delivery of high-quality, standardized, outcome-orientated CTS training across Europe.

Challenges and satisfaction in Cardiothoracic Surgery Residency Programmes: insights from a Europe-wide survey.

OBJECTIVES: The increasing complexity of surgical patients and working time constraints represent challenges for training. In this study, the European Association for Cardio-Thoracic Surgery Residents' Committee aimed to evaluate satisfaction with current training programmes across Europe. METHODS: We conducted an online survey between October 2018 and April 2019, completed by a total of 219 participants from 24 countries. RESULTS: The average respondent was in the fourth or fifth year of training, mostly on a cardiac surgery pathway. Most trainees follow a 5-6-year programme, with a compulsory final certification exam, but no regular skills evaluation. Only a minority are expected to take the examination by the European Board of Cardiothoracic Surgery. Participants work on average 61.0 ± 13.1 h per week, including 27.1 ± 20.2 on-call. In total, only 19.7% confirmed the implementation of the European Working Time Directive, with 42.0% being unaware that European regulations existed. Having designated time for research was reported by 13.0%, despite 47.0% having a postgraduate degree. On average, respondents rated their satisfaction 7.9 out of 10, although 56.2% of participants were not satisfied with their training opportunities. We found an association between trainee satisfaction and regular skills evaluation, first operator experience and protected research time. CONCLUSIONS: On average, residents are satisfied with their training, despite significant disparities in the quality and structure of cardiothoracic surgery training across Europe. Areas for potential improvement include increasing structured feedback, research time integration and better working hours compliance. The development of European guidelines on training standards may support this.

Prevention of Cardiac Surgery-Associated Acute Kidney Injury: A Review of Current Strategies.

Acute kidney injury is a common and often severe postoperative complication after cardiac surgery, and is associated with poor short-term and long-term outcomes. Numerous randomized controlled trials have been conducted to investigate various strategies for prevention of cardiac surgery-associated acute kidney injury. Unfortunately, most trials that have been conducted to date have been negative. However, encouraging results have been demonstrated with preoperative administration of corticosteroids, leukocyte filtration, and administration of inhaled nitric oxide intraoperatively, and implementation of a Kidney Disease: Improving Global Outcomes bundle of care approach postoperatively. These findings require validation in large, multicenter trials.

Surgical Treatment of Acute Thoracic Stent Graft Occlusion.

A 24-year-old man presented with acute onset paraplegia related to complete occlusion of a thoracic stent graft placed 2 years prior for repair of traumatic type B aortic dissection. Following emergency surgery comprising reestablishment of aortic flow by stent removal and aortic reconstruction, the paraplegia started to resolve partly, despite an estimated 5-hour interval of preoperative myelum ischemia. Anatomical characteristics of the stent graft placement appear to have played a role in causing this rare complication. Six months later, the patient could walk again with a stick. This case shows that early intervention in cases of full paraplegia may be considered.

White blood cell count and new-onset atrial fibrillation after cardiac surgery.

BACKGROUND: Postoperative new-onset atrial fibrillation (PNAF) is the most common complication following cardiac surgery. The inflammatory response, as a potential underlying mechanism, has been extensively studied. In small studies, the white blood cell count (WBC) has been shown to be the only consistent inflammatory marker associated with PNAF. This study aimed to determine the association between perioperative WBC response and PNAF in a larger study cohort. METHODS: Patients ≥18years, undergoing elective cardiac surgery with a preoperative sinus rhythm were included. WBC was routinely measured preoperatively, and daily during the first four postoperative days. Main outcomes were the difference between peak postoperative WBC and neutrophil/lymphocyte ratio (N/L ratio) and preoperative WBC and N/L ratio (ΔWBC and ΔN/L ratio respectively). Development of PNAF was evaluated in all patients with continuous 12-lead ECG monitoring. RESULTS: 657 patients were included and 277 (42%) developed PNAF. Univariable analyses showed a statistically significant relationship between ΔWBC (P=0.030) and ΔN/L ratio (P=0.002), and PNAF. In multivariable analysis no significant relationship was found between ΔWBC (OR: 1.14 per 1×109/L increase; 95% CI: 0.65-2.03; P=0.645), ΔN/L ratio (OR: 1.65 per 1×109/L increase; 95% CI: 0.94-2.90; P=0.089), and PNAF. Increasing age (OR: 1.08 per year; 95% CI: 1.01-1.16; P=0.022) and (additional) valve surgery (versus CABG) (OR: 4.96; 95% CI: 2.07-6.91; P≤0.001) were associated with PNAF. CONCLUSIONS: The perioperative WBC response and its components were not associated with the development of PNAF.

Mortality after cardiac surgery in patients with liver cirrhosis classified by the Child-Pugh score.

Liver cirrhosis is a known risk factor for postoperative mortality in patients undergoing cardiac surgery. Clinical assessment of liver cirrhosis using the widely accepted Child-Pugh (CP) score is thus vital for evaluation of surgical options and perioperative care. However, detailed mortality rates as a consequence of liver cirrhosis are unclear. This review aimed to stratify the risk of short-term (<30 days) and overall (up to 10 years) mortality after cardiac surgery in patients with liver cirrhosis, classified by the CP score. Thus, PubMed, Embase, CINAHL and the Cochrane Library were systematically reviewed by two independent investigators for studies published up to February 2014, in which mortality in cirrhotic patients, classified by the CP classification, undergoing cardiac surgery was evaluated postoperatively. A total of 993 articles were identified. After critical appraisal of 21 articles, 19 were selected for final analysis. Weighted short-term mortality of cirrhotic patients undergoing cardiac surgery was 19.3% [95% confidence interval (CI): 16.4-22.5%]. Across the different CP groups, short-term mortality appeared to be 9.0% (95% CI: 6.6-12.2%), 37.7% (95% CI: 30.8-44.3%) and 52.0% (95% CI: 33.5-70.0%) in Groups A, B and C, respectively. Weighted overall mortality within 1 year was 42.0% (95% CI: 36.0-48.3%) in all cirrhotic patients. Subdivided in groups, overall mortality within that 1 year was 27.2% (95% CI: 20.9-34.7%), 66.2% (95% CI: 54.3-76.3%) and 78.9% (95% CI: 56.1-92.1%) in Groups A, B and C, respectively. In conclusion, short-term mortality is considerably increased in patients with liver cirrhosis CP class B and C. Overall mortality is significantly high in all classes of liver cirrhosis.

Dexamethasone for the prevention of postoperative atrial fibrillation.

BACKGROUND: Postoperative atrial fibrillation (AF) is a common complication after cardiac surgery. Inflammation is believed to play a pivotal role in the etiology of postoperative AF. There is a suggestion from small studies that perioperative treatment with corticosteroids may reduce postoperative AF. The DExamethasone for Cardiac Surgery (DECS) study was a large randomized trial showing no protective effect of dexamethasone on major adverse events. The aim of this study was to investigate the effect of dexamethasone treatment on the occurrence of AF after cardiac surgery. METHODS: The DECS study compared intra-operative dexamethasone (1mg/kg) or placebo treatment in 4494 adult patients undergoing cardiac surgery. AF was defined by the occurrence of any reported AF within 30days after surgery. We also performed an in-depth analysis of a subset of 1565 patients on new-onset AF. Relative risks (RRs) with 95% confidence intervals (CIs) were calculated. RESULTS: The incidence of any AF in the main study of 4494 patients was 33.1% in the dexamethasone and 35.2% in the placebo group (RR 0.94, 95% CI: 0.87-1.02, p=0.14). In the substudy of 1565 patients, the incidence of new-onset AF was 33.0% vs. 35.5% (RR 0.93, 95% CI: 0.81-1.07, p=0.31), respectively. There was no protective effect of dexamethasone across clinically important patient subgroups. CONCLUSION: Intraoperative administration of dexamethasone had no protective effect on the occurrence of any or new-onset atrial fibrillation after cardiac surgery. Therefore, the use of dexamethasone for the reduction of postoperative AF should not be recommended.