Inequalities in access to and outcomes of cardiac surgery in England: retrospective analysis of Hospital Episode Statistics (2010-2019)

BACKGROUND

We aimed to characterise the variation in access to and outcomes of cardiac surgery for people in England.

METHODS

We included people >18 years of age with hospital admission for ischaemic heart disease (IHD) and heart valve disease (HVD) between 2010 and 2019. Within these populations, we identified people who had coronary artery bypass graft (CABG) and/or valve surgery, respectively. We fitted logistic regression models to examine the effects of age, sex, ethnicity and socioeconomic deprivation on having access to surgery and in-hospital mortality, 1-year mortality and hospital readmission.

RESULTS

We included 292 140 people, of whom 28% were women, 11% were from an ethnic minority and 17% were from the most deprived areas. Across all types of surgery, one in five people are readmitted to hospital within 1 year, rising to almost one in four for valve surgery. Women, black people and people living in the most deprived areas were less likely to have access to surgery (CABG: 59%, 32% and 35% less likely; valve: 31%, 33% and 39% less likely, respectively) and more likely to die within 1 year of surgery (CABG: 24%, 85% and 18% more likely, respectively; valve: 19% (women) and 10% (people from most deprived areas) more likely).

CONCLUSIONS

Female sex, black ethnicity and economic deprivation are independently associated with limited access to cardiac surgery and higher post-surgery mortality. Actions are required to address these inequalities.

Spatial Transcriptomic Profiling of Human Saphenous Vein Exposed to Ex Vivo Arterial Haemodynamics-Implications for Coronary Artery Bypass Graft Patency and Vein Graft Disease

Vein graft disease is the process by which saphenous vein grafts, utilised for revascularisation during coronary artery bypass graft surgery, undergo an inflammation-driven intimal hyperplasia and accelerated atherosclerosis process in subsequent years after implantation. The role of the arterial circulation, particularly the haemodynamic properties' impact on graft patency, have been investigated but have not to date been explored in depth at the transcriptomic level. We have undertaken the first-in-man spatial transcriptomic analysis of the long saphenous vein in response to ex vivo acute arterial haemodynamic stimulation, utilising a combination of a custom 3D-printed perfusion bioreactor and the 10X Genomics Visium Spatial Gene Expression technology. We identify a total of 413 significant genes (372 upregulated and 41 downregulated) differentially expressed in response to arterial haemodynamic conditions. These genes were associated with pathways including NFkB, TNF, MAPK, and PI3K/Akt, among others. These are established pathways involved in the initiation of an early pro-inflammatory response, leukocyte activation and adhesion signalling, tissue remodelling, and cellular differentiation. Utilising unsupervised clustering analysis, we have been able to classify subsets of the expression based on cell type and with spatial resolution. These findings allow for further characterisation of the early saphenous vein graft transcriptional landscape during the earliest stage of implantation that contributes to vein graft disease, in particular validation of pathways and druggable targets that could contribute towards the therapeutic inhibition of processes underpinning vein graft disease.

Rationale and design of the early valve replacement in severe asymptomatic aortic stenosis trial

BACKGROUND

Aortic valve replacement in asymptomatic severe aortic stenosis is controversial. The Early valve replacement in severe ASYmptomatic Aortic Stenosis (EASY-AS) trial aims to determine whether early aortic valve replacement improves clinical outcomes, quality of life and cost-effectiveness compared to a guideline recommended strategy of 'watchful waiting'.

METHODS

In a pragmatic international, open parallel group randomized controlled trial (NCT04204915), 2844 patients with severe aortic stenosis will be randomized 1:1 to either a strategy of early (surgical or transcatheter) aortic valve replacement or aortic valve replacement only if symptoms or impaired left ventricular function develop, or other cardiac surgery becomes nessessary. Exclusion criteria include other severe valvular disease, planned cardiac surgery, ejection fraction <50%, previous aortic valve replacement or life expectancy <2 years. The primary outcome is a composite of cardiovascular mortality or heart failure hospitalization. The primary analysis will be undertaken when 663 primary events have accrued, providing 90% power to detect a reduction in the primary endpoint from 27.7% to 21.6% (hazard ratio 0.75). Secondary endpoints include disability-free survival, days alive and out of hospital, major adverse cardiovascular events and quality of life.

RESULTS

Recruitment commenced in March 2020 and is open in the UK, Australia, New Zealand, and Serbia. Feasibility requirements were met in July 2022, and the main phase opened in October 2022, with additional international centers in set-up.

CONCLUSIONS

The EASY-AS trial will establish whether a strategy of early aortic valve replacement in asymptomatic patients with severe aortic stenosis reduces cardiovascular mortality or heart failure hospitalization and improves other important outcomes.

A comprehensive qualitative investigation of the factors that affect surgical site infection prevention in cardiac surgery in England using observations and interviews

BACKGROUND

Interview and questionnaire studies have identified barriers and challenges to preventing surgical site infections (SSIs) by focusing on compliance with recommendations and care bundles using interviews, questionnaires and expert panels. This study proposes a more comprehensive investigation by using observations of clinical practice plus interviews which will enable a wider focus.

AIM

To comprehensively identify the factors which affect SSI prevention using cardiac surgery as an exemplar.

METHODS

The study consisted of 130 h of observed clinical practice followed by individual semi-structured interviews with 16 surgeons, anaesthetists, theatre staff, and nurses at four cardiac centres in England. Data were analysed thematically.

FINDINGS

The factors were complex and existed at the level of the intervention, the individual, the team, the organization, and even the wider society. Factors included: the attributes of the intervention; the relationship between evidence, personal beliefs, and perceived risk; power and hierarchy; leadership and culture; resources; infrastructure; supplies; organization and planning; patient engagement and power; hospital administration; workforce shortages; COVID-19 pandemic; 'Brexit'; and the war in Ukraine.

CONCLUSION

This is one of the first studies to provide a comprehensive overview of the factors affecting SSI prevention. The factors are complex and need to be fully understood when trying to reduce SSIs. A strong evidence base was insufficient to ensure implementation of an intervention.

Comparison between propofol and total inhalational anaesthesia on cardiovascular outcomes following on-pump cardiac surgery in higher-risk patients: a randomised controlled pilot and feasibility study

OBJECTIVES

Myocardial revascularisation and cardiopulmonary bypass (CPB) can cause ischaemia-reperfusion injury, leading to myocardial and other end-organ damage. Volatile anaesthetics protect the myocardium in experimental studies. However, there is uncertainty about whether this translates into clinical benefits because of the coadministration of propofol and its detrimental effects, restricting myocardial protective processes.

METHODS

In this single-blinded, parallel-group randomised controlled feasibility trial, higher-risk patients undergoing elective coronary artery bypass graft (CABG) surgery with an additive European System for Cardiac Operative Risk Evaluation ≥5 were randomised to receive either propofol or total inhalational anaesthesia as single agents for maintenance of anaesthesia. The primary outcome was the feasibility of recruiting and randomising 50 patients across two cardiac surgical centres, and secondary outcomes included the feasibility of collecting the planned perioperative data, clinically relevant outcomes and assessments of effective patient identification, screening and recruitment.

RESULTS

All 50 patients were recruited within 11 months in two centres, allowing for a 13-month hiatus in recruitment due to the COVID-19 pandemic. Overall, 50/108 (46%) of eligible patients were recruited. One patient withdrew before surgery and one patient did not undergo surgery. All but one completed in-hospital and 30-day follow-up.

CONCLUSIONS

It is feasible to recruit and randomise higher-risk patients undergoing CABG surgery to a study comparing total inhalational and propofol anaesthesia in a timely manner and with high acceptance and completion rates.

TRIAL REGISTRATION NUMBER

NCT04039854.

Unfractionated heparin reverses aspirin inhibition of platelets during coronary artery bypass graft surgery

Unfractionated heparin (UFH) is an effective antithrombotic during surgery but has known adverse effects, in particular on platelets. A marked increase in platelet responsiveness has previously been observed in patients within minutes of receiving UFH, despite adequate inhibition by aspirin prior to heparin. We studied this phenomenon in patients undergoing cardiac artery bypass grafting (n = 17) to determine whether the effects of heparin were systemic or platelet-specific. All patients' platelets were fully inhibited by aspirin prior to surgery, but within 3 min of receiving heparin spontaneous aggregation and responses to arachidonic acid (AA) and ADP increased significantly (p ≥ 0.0002), and activated platelets were found in the circulation. While there was no rise in thromboxane in the plasma following heparin, levels of the major platelet 12-lipoxygenase product, 12-HETE, rose significantly. Mixing experiments demonstrated that the changes caused by heparin resided primarily in the platelets, while addition of AA pathway inhibitors, and analysis of oxylipins provided evidence that, following heparin, aggregating platelets regained their ability to synthesise thromboxane. These findings highlight potentially unrecognised pro-thrombotic and pro-inflammatory changes during CABG surgery, and provide further evidence of adverse effects associated with UFH.

Prophylactic corticosteroids for cardiopulmonary bypass in adult cardiac surgery

BACKGROUND

Cardiac surgery triggers a strong inflammatory reaction, which carries significant clinical consequences. Corticosteroids have been suggested as a potential perioperative strategy to reduce inflammation and help prevent postoperative complications. However, the safety and effectiveness of perioperative corticosteroid use in adult cardiac surgery is uncertain. This is an update of the 2011 review with 18 studies added.

OBJECTIVES

Primary objective: to estimate the effects of prophylactic corticosteroid use in adults undergoing cardiac surgery with cardiopulmonary bypass on the: - co-primary endpoints of mortality, myocardial complications, and pulmonary complications; and - secondary outcomes including atrial fibrillation, infection, organ injury, known complications of steroid therapy, prolonged mechanical ventilation, prolonged postoperative stay, and cost-effectiveness.

SECONDARY OBJECTIVE

to explore the role of characteristics of the study cohort and specific features of the intervention in determining the treatment effects via a series of prespecified subgroup analyses.

SEARCH METHODS

We used standard, extensive Cochrane search methods to identify randomised studies assessing the effect of corticosteroids in adult cardiac surgery. The latest searches were performed on 14 October 2022.

SELECTION CRITERIA

We included randomised controlled trials in adults (over 18 years, either with a diagnosis of coronary artery disease or cardiac valve disease, or who were candidates for cardiac surgery with the use of cardiopulmonary bypass), comparing corticosteroids with no treatments. There were no restrictions with respect to length of the follow-up period. All selected studies qualified for pooling of results for one or more endpoints.

DATA COLLECTION AND ANALYSIS

We used standard Cochrane methods. Our primary outcomes were all-cause mortality, and cardiac and pulmonary complications. Secondary outcomes were infectious complications, gastrointestinal bleeding, occurrence of new post-surgery atrial fibrillation, re-thoracotomy for bleeding, neurological complications, renal failure, inotropic support, postoperative bleeding, mechanical ventilation time, length of stays in the intensive care unit (ICU) and hospital, patient quality of life, and cost-effectiveness. We used GRADE to assess the certainty of evidence for each outcome.

MAIN RESULTS

This updated review includes 72 randomised trials with 17,282 participants (all 72 trials with 16,962 participants were included in data synthesis). Four trials (6%) were considered at low risk of bias in all the domains. The median age of participants included in the studies was 62.9 years. Study populations consisted mainly (89%) of low-risk, first-time coronary artery bypass grafting (CABG) or valve surgery. The use of perioperative corticosteroids may result in little to no difference in all-cause mortality (risk with corticosteroids: 25 to 36 per 1000 versus 33 per 1000 with placebo or no treatment; risk ratio (RR) 0.90, 95% confidence interval (CI) 0.75 to 1.07; 25 studies, 14,940 participants; low-certainty evidence). Corticosteroids may increase the risk of myocardial complications (68 to 86 per 1000) compared with placebo or no treatment (66 per 1000; RR 1.16, 95% CI 1.04 to 1.31; 25 studies, 14,766 participants; low-certainty evidence), and may reduce the risk of pulmonary complications (risk with corticosteroids: 61 to 77 per 1000 versus 78 per 1000 with placebo/no treatment; RR 0.88, 0.78 to 0.99; 18 studies, 13,549 participants; low-certainty evidence). Analyses of secondary endpoints showed that corticosteroids may reduce the incidence of infectious complications (risk with corticosteroids: 94 to 113 per 1000 versus 123 per 1000 with placebo/no treatment; RR 0.84, 95% CI 0.76 to 0.92; 28 studies, 14,771 participants; low-certainty evidence). Corticosteroids may result in little to no difference in incidence of gastrointestinal bleeding (risk with corticosteroids: 9 to 17 per 1000 versus 10 per 1000 with placebo/no treatment; RR 1.21, 95% CI 0.87 to 1.67; 6 studies, 12,533 participants; low-certainty evidence) and renal failure (risk with corticosteroids: 23 to 35 per 1000 versus 34 per 1000 with placebo/no treatment; RR 0.84, 95% CI 0.69 to 1.02; 13 studies, 12,799; low-certainty evidence). Corticosteroids may reduce the length of hospital stay, but the evidence is very uncertain (-0.5 days, 0.97 to 0.04 fewer days of length of hospital stay compared with placebo/no treatment; 25 studies, 1841 participants; very low-certainty evidence). The results from the two largest trials included in the review possibly skew the overall findings from the meta-analysis.

AUTHORS' CONCLUSIONS

A systematic review of trials evaluating the organ protective effects of corticosteroids in cardiac surgery demonstrated little or no treatment effect on mortality, gastrointestinal bleeding, and renal failure. There were opposing treatment effects on cardiac and pulmonary complications, with evidence that corticosteroids may increase cardiac complications but reduce pulmonary complications; however, the level of certainty for these estimates was low. There were minor benefits from corticosteroid therapy for infectious complications, but the evidence on hospital length of stay was very uncertain. The inconsistent treatment effects across different outcomes and the limited data on high-risk groups reduced the applicability of the findings. Further research should explore the role of these drugs in specific, vulnerable cohorts.

Frailty in acute coronary syndromes. A systematic review and narrative synthesis of frailty assessment tools and interventions from randomised controlled trials

AIM

We aimed to review all randomised controlled trial (RCT) data to explore optimal identification and treatment strategies of frail patients with Acute Coronary Syndromes (ACS).

METHODS

The protocol was preregistered (PROSPERO - CRD42021250235). We performed a systematic review including RCT's that 1; used at least one frailty assessment tool to assess frailty and its impact on outcomes in patients diagnosed with ACS and 2; used at least one intervention where change in frailty was measured in patients diagnosed with ACS. The Cochrane Central Register of Controlled Trials, MEDLINE and EMBASE were searched on the 1st April 2021 and updated on 4th July 2023. Owing to low search output results are presented as a narrative synthesis of available evidence.

RESULTS

A single RCT used a frailty assessment tool. A single RCT specifically targeted frailty with their intervention. This precluded further quantitative analysis. There was indication of selection bias against frail participants, and a signal of value for physical activity measurement in frail ACS patients. There was a high level of uncertainty and low level of robustness of this evidence.

CONCLUSIONS

Data from RCT's alone is inadequate in answering the reviews question. Future RCT's need to address ways to incorporate frail participants, whilst mitigating selection biases. Physical performance aspects of the frailty syndrome appear to be high yield modifiable targets that improve outcomes. Intervention trials should consider using change in frailty status as an outcome measure. Any trials that include frail participants should present data specifically attributable to this group.

Osteopontin Activation and Microcalcification in Venous Grafts Can Be Modulated by Dexamethasone

BACKGROUND

Osteopontin has been implicated in vascular calcification formation and vein graft intimal hyperplasia, and its expression can be triggered by pro-inflammatory activation of cells. The role of osteopontin and the temporal formation of microcalcification in vein grafts is poorly understood with a lack of understanding of the interaction between haemodynamic changes and the activation of osteopontin.

METHODS

We used a porcine model of vein interposition grafts, and human long saphenous veins exposed to ex vivo perfusion, to study the activation of osteopontin using polymerase chain reaction, immunostaining, and 18F-sodium fluoride autoradiography.

RESULTS

The porcine model showed that osteopontin is active in grafts within 1 week following surgery and demonstrated the presence of microcalcification. A brief pretreatment of long saphenous veins with dexamethasone can suppress osteopontin activation. Prolonged culture of veins after exposure to acute arterial haemodynamics resulted in the formation of microcalcification but this was suppressed by pretreatment with dexamethasone. 18F-sodium fluoride uptake was significantly increased as early as 1 week in both models, and the pretreatment of long saphenous veins with dexamethasone was able to abolish its uptake.

CONCLUSIONS

Osteopontin is activated in vein grafts and is associated with microcalcification formation. A brief pretreatment of veins ex vivo with dexamethasone can suppress its activation and associated microcalcification.

Effects of interventions targeting the systemic inflammatory response to cardiac surgery on clinical outcomes in adults

BACKGROUND

Organ injury is a common and severe complication of cardiac surgery that contributes to the majority of deaths. There are no effective treatment or prevention strategies. It has been suggested that innate immune system activation may have a causal role in organ injury. A wide range of organ protection interventions targeting the innate immune response have been evaluated in randomised controlled trials (RCTs) in adult cardiac surgery patients, with inconsistent results in terms of effectiveness.

OBJECTIVES

The aim of the review was to summarise the results of RCTs of organ protection interventions targeting the innate immune response in adult cardiac surgery. The review considered whether the interventions had a treatment effect on inflammation, important clinical outcomes, or both.

SEARCH METHODS

CENTRAL, MEDLINE, Embase, conference proceedings and two trial registers were searched on October 2022 together with reference checking to identify additional studies.

SELECTION CRITERIA

RCTs comparing organ protection interventions targeting the innate immune response versus placebo or no treatment in adult patients undergoing cardiac surgery where the treatment effect on innate immune activation and on clinical outcomes of interest were reported.

DATA COLLECTION AND ANALYSIS

Searches, study selection, quality assessment, and data extractions were performed independently by pairs of authors. The primary inflammation outcomes were peak IL-6 and IL-8 concentrations in blood post-surgery. The primary clinical outcome was in-hospital or 30-day mortality. Treatment effects were expressed as risk ratios (RR) and standardised mean difference (SMD) with 95% confidence intervals (CI). Meta-analyses were performed using random effects models, and heterogeneity was assessed using I2.

MAIN RESULTS

A total of 40,255 participants from 328 RCTs were included in the synthesis. The effects of treatments on IL-6 (SMD -0.77, 95% CI -0.97 to -0.58, I2 = 92%) and IL-8 (SMD -0.92, 95% CI -1.20 to -0.65, I2 = 91%) were unclear due to heterogeneity. Heterogeneity for inflammation outcomes persisted across multiple sensitivity and moderator analyses. The pooled treatment effect for in-hospital or 30-day mortality was RR 0.78, 95% CI 0.68 to 0.91, I2 = 0%, suggesting a significant clinical benefit. There was little or no treatment effect on mortality when analyses were restricted to studies at low risk of bias. Post hoc analyses failed to demonstrate consistent treatment effects on inflammation and clinical outcomes. Levels of certainty for pooled treatment effects on the primary outcomes were very low.

AUTHORS' CONCLUSIONS

A systematic review of RCTs of organ protection interventions targeting innate immune system activation did not resolve uncertainty as to the effectiveness of these treatments, or the role of innate immunity in organ injury following cardiac surgery.

The NightLife study - the clinical and cost-effectiveness of thrice-weekly, extended, in-centre nocturnal haemodialysis versus daytime haemodialysis using a mixed methods approach: study protocol for a randomised controlled trial

BACKGROUND

In-centre nocturnal haemodialysis (INHD) offers extended-hours haemodialysis, 6 to 8 h thrice-weekly overnight, with the support of dialysis specialist nurses. There is increasing observational data demonstrating potential benefits of INHD on health-related quality of life (HRQoL). There is a lack of randomised controlled trial (RCT) data to confirm these benefits and assess safety.

METHODS

The NightLife study is a pragmatic, two-arm, multicentre RCT comparing the impact of 6 months INHD to conventional haemodialysis (thrice-weekly daytime in-centre haemodialysis, 3.5-5 h per session). The primary outcome is the total score from the Kidney Disease Quality of Life tool at 6 months. Secondary outcomes include sleep and cognitive function, measures of safety, adherence to dialysis and impact on clinical parameters. There is an embedded Process Evaluation to assess implementation, health economic modelling and a QuinteT Recruitment Intervention to understand factors that influence recruitment and retention. Adults (≥ 18 years old) who have been established on haemodialysis for > 3 months are eligible to participate.

DISCUSSION

There are 68,000 adults in the UK that need kidney replacement therapy (KRT), with in-centre haemodialysis the treatment modality for over a third of cases. HRQoL is an independent predictor of hospitalisation and mortality in individuals on maintenance dialysis. Haemodialysis is associated with poor HRQoL in comparison to the general population. INHD has the potential to improve HRQoL. Vigorous RCT evidence of effectiveness is lacking. The NightLife study is an essential step in the understanding of dialysis therapies and will guide patient-centred decisions regarding KRT in the future.

TRIAL REGISTRATION

Trial registration number: ISRCTN87042063. Registered: 14/07/2020.

Outcome monitoring and risk stratification after cardiac procedure in neonates, infants, children and young adults born with congenital heart disease: protocol for a multicentre prospective cohort study (Children OMACp)

INTRODUCTION

Congenital heart disease (CHD) represents the most common birth defect, affecting from 0.4% to 1.2% of children born in developed countries. The survival of these patients has increased significantly, but CHD remains one of the major causes of neonatal and childhood death. The aetiology of CHD is complex, with some evidence of both genetic and environmental causes. However, there is still lack of knowledge regarding modifiable risk factors and molecular and genetic mechanisms underlying the development of CHD. This study aims to develop a prospective cohort of patients undergoing cardiac procedures that will bring together routinely collected clinical data and biological samples from patients and their biological mothers, in order to investigate risk factors and predictors of postoperative-outcomes, as well as better understanding the effect of the surgical intervention on the early and long-term outcomes.

METHODS AND ANALYSIS

Children OMACp (OMACp, outcome monitoring after cardiac procedure in congenital heart disease) is a multicentre, prospective cohort study recruiting children with CHD undergoing a cardiac procedure. The study aims to recruit 3000 participants over 5 years (2019-2024) across multiple UK sites. Routine clinical data will be collected, as well as participant questionnaires collecting sociodemographic, NHS resource use and quality of life data. Biological samples (blood, urine and surgical waste tissue from patients, and blood and urine samples from biological mothers) will be collected where consent has been obtained. Follow-up outcome and questionnaire data will be collected for 5 years.

ETHICS AND DISSEMINATION

The study was approved by the London-Brent Research Ethics Committee on 30 July 2019 (19/SW/0113). Participants (or their parent/guardian if under 16 years of age) must provide informed consent prior to being recruited into the study. Mothers who wish to take part must also provide informed consent prior to being recruited. The study is sponsored by University Hospitals Bristol and Weston Foundation Trust and is managed by the University of Bristol. Children OMACp is adopted onto the National Institute for Health Research Clinical Research Network portfolio. Findings will be disseminated through peer-reviewed publications, presentation at conference, meetings and through patient organisations and newsletters.

TRIAL REGISTRATION NUMBER

ISRCTN17650644.

Data standards for transcatheter aortic valve implantation: the European Unified Registries for Heart Care Evaluation and Randomised Trials (EuroHeart)

AIMS

Standardized data definitions are necessary for the quantification of quality of care and patient outcomes in observational studies and randomised controlled trials (RCTs). The European Unified Registries for Heart Care Evaluation and Randomised Trials (EuroHeart) project of the European Society of Cardiology (ESC) aims to create pan-European data standards for cardiovascular diseases and interventions, including transcatheter aortic valve implantation (TAVI).

METHODS AND RESULTS

We followed the EuroHeart methodology for cardiovascular data standard development. A Working Group of 29 members representing 12 countries was established and included a patient representative, as well as experts in the management of valvular heart disease from the European Association of Percutaneous Cardiovascular Interventions (EAPCI), the European Association of Cardiovascular Imaging (EACVI) and the Working Group on Cardiovascular Surgery. We conducted a systematic review of the literature and used a modified Delphi method to reach consensus on a final set of variables. For each variable, the Working Group provided a definition, permissible values, and categorized the variable as mandatory (Level 1) or additional (Level 2) based on its clinical importance and feasibility. In total, 93 Level 1 and 113 Level 2 variables were selected, with the level 1 variables providing the dataset for registration of patients undergoing TAVI on the EuroHeart IT platform.

CONCLUSION

This document provides details of the EuroHeart data standards for TAVI processes of care and in-hospital outcomes. In the context of EuroHeart, this will facilitate quality improvement, observational research, registry-based RCTs and post-marketing surveillance of devices, and pharmacotherapies.

ONE-SENTENCE SUMMARY

The EuroHeart data standards for transcatheter aortic valve implantation (TAVI) are a set of internationally agreed data variables and definitions that once implemented will facilitate improvement of quality of care and outcomes for patients receiving TAVI.

Minithoracotomy vs Conventional Sternotomy for Mitral Valve Repair: A Randomized Clinical Trial

Importance

The safety and effectiveness of mitral valve repair via thoracoscopically-guided minithoracotomy (minithoracotomy) compared with median sternotomy (sternotomy) in patients with degenerative mitral valve regurgitation is uncertain.

Objective

To compare the safety and effectiveness of minithoracotomy vs sternotomy mitral valve repair in a randomized trial.

Design, Setting, and Participants

A pragmatic, multicenter, superiority, randomized clinical trial in 10 tertiary care institutions in the UK. Participants were adults with degenerative mitral regurgitation undergoing mitral valve repair surgery.

Interventions

Participants were randomized 1:1 with concealed allocation to receive either minithoracotomy or sternotomy mitral valve repair performed by an expert surgeon.

Main Outcomes and Measures

The primary outcome was physical functioning and associated return to usual activities measured by change from baseline in the 36-Item Short Form Health Survey (SF-36) version 2 physical functioning scale 12 weeks after the index surgery, assessed by an independent researcher masked to the intervention. Secondary outcomes included recurrent mitral regurgitation grade, physical activity, and quality of life. The prespecified safety outcomes included death, repeat mitral valve surgery, or heart failure hospitalization up to 1 year.

Results

Between November 2016 and January 2021, 330 participants were randomized (mean age, 67 years, 100 female [30%]); 166 were allocated to minithoracotomy and 164 allocated to sternotomy, of whom 309 underwent surgery and 294 reported the primary outcome. At 12 weeks, the mean between-group difference in the change in the SF-36 physical function T score was 0.68 (95% CI, -1.89 to 3.26). Valve repair rates (≈ 96%) were similar in both groups. Echocardiography demonstrated mitral regurgitation severity as none or mild for 92% of participants at 1 year with no difference between groups. The composite safety outcome occurred in 5.4% (9 of 166) of patients undergoing minithoracotomy and 6.1% (10 of 163) undergoing sternotomy at 1 year.

Conclusions and relevance

Minithoracotomy is not superior to sternotomy in recovery of physical function at 12 weeks. Minithoracotomy achieves high rates and quality of valve repair and has similar safety outcomes at 1 year to sternotomy. The results provide evidence to inform shared decision-making and treatment guidelines.

Trial Registration

isrctn.org Identifier: ISRCTN13930454.

The Role of Preservation Solutions upon Saphenous Vein Endothelial Integrity and Function: Systematic Review and UK Practice Survey

The long saphenous vein is the most used conduit in cardiac surgery, but its long-term patency is limited by vein graft disease (VGD). Endothelial dysfunction is a key driver of VGD; its aetiology is multi-factorial. However emerging evidence identifies vein conduit harvest technique and preservation fluids as causal in their onset and propagation. This study aims to comprehensively review published data on the relationship between preservation solutions, endothelial cell integrity and function, and VGD in human saphenous veins harvested for CABG. The review was registered with PROSPERO (CRD42022358828). Electronic searches of Cochrane Central Register of Controlled Trials, MEDLINE, and EMBASE databases were undertaken from inception until August 2022. Papers were evaluated in line with registered inclusion and exclusion criteria. Searches identified 13 prospective, controlled studies for inclusion in the analysis. All studies used saline as a control solution. Intervention solutions included heparinised whole blood and saline, DuraGraft, TiProtec, EuroCollins, University of Wisconsin (UoW), buffered, cardioplegic and Pyruvate solutions. Most studies demonstrated that normal saline appears to have negative effects on venous endothelium and the most effective preservation solutions identified in this review were TiProtec and DuraGraft. The most used preservation solutions in the UK are heparinised saline or autologous whole blood. There is substantial heterogeneity both in practice and reporting of trials evaluating vein graft preservation solutions, and the quality of existing evidence is low. There is an unmet need for high quality trials evaluating the potential for these interventions to improve long-term patency in venous bypass grafts.

The association between iron deficiency and outcomes: a secondary analysis of the intravenous iron therapy to treat iron deficiency anaemia in patients undergoing major abdominal surgery (PREVENTT) trial

In the intravenous iron therapy to treat iron deficiency anaemia in patients undergoing major abdominal surgery (PREVENTT) trial, the use of intravenous iron did not reduce the need for blood transfusion or reduce patient complications or length of hospital stay. As part of the trial protocol, serum was collected at randomisation and on the day of surgery. These samples were analysed in a central laboratory for markers of iron deficiency. We performed a secondary analysis to explore the potential interactions between pre-operative markers of iron deficiency and intervention status on the trial outcome measures. Absolute iron deficiency was defined as ferritin <30 μg.l^-1 ; functional iron deficiency as ferritin 30-100 μg.l^-1 or transferrin saturation < 20%; and the remainder as non-iron deficient. Interactions were estimated using generalised linear models that included different subgroup indicators of baseline iron status. Co-primary endpoints were blood transfusion or death and number of blood transfusions, from randomisation to 30 days postoperatively. Secondary endpoints included peri-operative change in haemoglobin, postoperative complications and length of hospital stay. Most patients had iron deficiency (369/452 [82%]) at randomisation; one-third had absolute iron deficiency (144/452 [32%]) and half had functional iron deficiency (225/452 [50%]). The change in pre-operative haemoglobin with intravenous iron compared with placebo was greatest in patients with absolute iron deficiency, mean difference 8.9 g.l^-1 , 95%CI 5.3-12.5; moderate in functional iron deficiency, mean difference 2.8 g.l^-1 , 95%CI -0.1 to 5.7; and with little change seen in those patients who were non-iron deficient. Subgroup analyses did not suggest that intravenous iron compared with placebo reduced the likelihood of death or blood transfusion at 30 days differentially across subgroups according to baseline ferritin (p = 0.33 for interaction), transferrin saturation (p = 0.13) or in combination (p = 0.45), or for the number of blood transfusions (p = 0.06, 0.29, and 0.39, respectively). There was no beneficial effect of the use of intravenous iron compared with placebo, regardless of the metrics to diagnose iron deficiency, on postoperative complications or length of hospital stay.

Surgical or percutaneous coronary revascularization for heart failure: an in silico model using routinely collected health data to emulate a clinical trial

AIMS

The choice of revascularization with coronary artery bypass grafting (CABG) vs. percutaneous coronary intervention (PCI) in people with ischaemic left ventricular dysfunction is not guided by high-quality evidence.

METHODS AND RESULTS

A trial of CABG vs. PCI in people with heart failure (HF) was modelled in silico using routinely collected healthcare data. The in silico trial cohort was selected by matching the target trial cohort, identified from Hospital Episode Statistics in England, with individual patient data from the Surgical Treatment for Ischemic Heart Failure (STICH) trial. Allocation to CABG vs. complex PCI demonstrated random variation across administrative regions in England and was a valid statistical instrument. The primary outcome was 5-year all-cause mortality or cardiovascular hospitalization. Instrumental variable analysis (IVA) was used for the primary analysis. Results were expressed as average treatment effects (ATEs) with 95 confidence intervals (CIs). The target population included 13 519 HF patients undergoing CABG or complex PCI between April 2009 and March 2015. After matching, the emulated trial cohort included 2046 patients. The unadjusted primary outcome rate was 51.1 in the CABG group and 70.0 in the PCI group. IVA of the emulated cohort showed that CABG was associated with a lower risk of the primary outcome (ATE 16.2, 95 CI 20.6 to 11.8), with comparable estimates in the unmatched target population (ATE 15.5, 95 CI 17.5 to 13.5).

CONCLUSION

In people with HF, in silico modelling suggests that CABG is associated with fewer deaths or cardiovascular hospitalizations at 5 years vs. complex PCI. A pragmatic clinical trial is needed to test this hypothesis and this trial would be feasible.

Next-Generation and Single-Cell Sequencing Approaches to Study Atherosclerosis and Vascular Inflammation Pathophysiology: A Systematic Review

Background and Aims

Atherosclerosis is a chronic inflammatory disease that remains the leading cause of morbidity and mortality worldwide. Despite decades of research into the development and progression of this disease, current management and treatment approaches remain unsatisfactory and further studies are required to understand the exact pathophysiology. This review aims to provide a comprehensive assessment of currently published data utilizing single-cell and next-generation sequencing techniques to identify key cellular and molecular contributions to atherosclerosis and vascular inflammation.

Methods

Electronic searches of Cochrane Central Register of Controlled Trials, MEDLINE, and EMBASE databases were undertaken from inception until February 2022. A narrative synthesis of all included studies was performed for all included studies. Quality assessment and risk of bias analysis was evaluated using the ARRIVE and SYRCLE checklist tools.

Results

Thirty-four studies were eligible for narrative synthesis, with 16 articles utilizing single-cell exclusively, 10 utilizing next-generation sequencing and 8 using a combination of these approaches. Studies investigated numerous targets, ranging from exploratory tissue and plaque analysis, cell phenotype investigation and physiological/hemodynamic contributions to disease progression at both the single-cell and whole genome level. A significant area of focus was placed on smooth muscle cell, macrophage, and stem/progenitor contributions to disease, with little focus placed on contributions of other cell types including lymphocytes and endothelial cells. A significant level of heterogeneity exists in the outcomes from single-cell sequencing of similar samples, leading to inter-sample and inter-study variation.

Conclusions

Single-cell and next-generation sequencing methodologies offer novel means of elucidating atherosclerosis with significantly higher resolution than previous methodologies. These approaches also show significant potential for translatability into other vascular disease states, by facilitating cell-specific gene expression profiles between disease states. Implementation of these technologies may offer novel approaches to understanding the disease pathophysiology and improving disease prevention, management, and treatment.Systematic Review Registration: https://www.crd.york.ac.uk/prospero/display_record.php?ID=CRD42021229960, identifier: CRD42021229960.

Transfusion strategies in bleeding critically ill adults: a clinical practice guideline from the European Society of Intensive Care Medicine

PURPOSE

To develop evidence-based clinical practice recommendations regarding transfusion practices and transfusion in bleeding critically ill adults.

METHODS

A taskforce involving 15 international experts and 2 methodologists used the GRADE approach to guideline development. The taskforce addressed three main topics: transfusion support in massively and non-massively bleeding critically ill patients (transfusion ratios, blood products, and point of care testing) and the use of tranexamic acid. The panel developed and answered structured guideline questions using population, intervention, comparison, and outcomes (PICO) format.

RESULTS

The taskforce generated 26 clinical practice recommendations (2 strong recommendations, 13 conditional recommendations, 11 no recommendation), and identified 10 PICOs with insufficient evidence to make a recommendation.

CONCLUSIONS

This clinical practice guideline provides evidence-based recommendations for the management of massively and non-massively bleeding critically ill adult patients and identifies areas where further research is needed.

Activation of the innate immune response and organ injury after cardiac surgery: a systematic review and meta-analysis of randomised trials and analysis of individual patient data from randomised and non-randomised studies

BACKGROUND

It is unclear whether the innate immune response represents a therapeutic target for organ protection strategies in cardiac surgery.

METHODS

A systematic review of trials of interventions targeting the inflammatory response to cardiac surgery reporting treatment effects on both innate immune system cytokines and organ injury was performed. The protocol was registered at the International Prospective Register of Systematic Reviews: CRD42020187239. Searches of the Cochrane Central Register of Controlled Trials, MEDLINE, and Embase were performed. Random-effects meta-analyses were used for the primary analysis. A separate analysis of individual patient data from six studies (n=785) explored sources of heterogeneity for treatment effects on cytokine levels.

RESULTS

Searches to May 2020 identified 251 trials evaluating 24 interventions with 20 582 participants for inclusion. Most trials had important limitations. Methodological limitations of the included trials and heterogeneity of the treatment effects on cytokine levels between trials limited interpretation. The primary analysis demonstrated inconsistency in the direction of the treatment effects on innate immunity and organ failure or death between interventions. Analyses restricted to important subgroups or trials with fewer limitations showed similar results. Meta-regression, pooling available data from all trials, demonstrated no association between the direction of the treatment effects on inflammatory cytokines and organ injury or death. The analysis of individual patient data demonstrated heterogeneity in the association between the cytokine response and organ injury after cardiac surgery for people >75 yr old and those with some chronic diseases.

CONCLUSIONS

The certainty of the evidence for a causal relationship between innate immune system activation and organ injury after cardiac surgery is low.

A systematic review and meta-analysis of studies that have evaluated the role of mitochondrial function and iron metabolism in frailty

Frailty is a condition of global impairment due to depletion of physiological reserves. However, the underlying biological mechanisms are poorly understood. The aims of the current study were to identify the differences in mitochondrial function and iron metabolism between frail and nonfrail populations, and to investigate the contribution of different methodological approaches to the results. Searches were performed, using five online databases up to November 2019. Studies reporting measurements of mitochondrial function or iron metabolism in frail and nonfrail subjects or subjects with and without sarcopenia, were included. Pooled effect estimates were expressed as Standardized Mean Differences. Heterogeneity, expressed as I², was explored using regression analyses. In total, 107 studies, reporting 75 measures of mitochondrial function or iron metabolism, using six different experimental approaches, in three species were identified. Significant decreases in measures of oxygen consumption were observed for frail humans but not in animal models. Conversely, no differences between frail and nonfrail humans were observed for apoptosis and autophagy, in contrast to animal models. The most significant effect of the type of frailty assessment was observed for respiratory chain complexes where only subjects categorized as frail by the Fried Frailty Index showed a significant decrease in activity. We identified iron metabolism in frailty as an important knowledge gap, highlighted the need of consistent frailty diagnostic tools, and pointed out the limited translational potential of animal models. Inconsistency between studies evaluating the molecular mechanisms underlying frailty may present a barrier to the development of effective therapies.

Interventions to prevent and treat sarcopenia in a surgical population: a systematic review and meta-analysis

BACKGROUND

The aim of this systematic review was to summarize the results of trials evaluating interventions for the reduction of sarcopenia in patients undergoing surgery.

METHODS

Searches were conducted using the Cochrane Central Register of Controlled Trials, MEDLINE and Embase. RCTs evaluating exercise, dietary or pharmacological interventions to address sarcopenia in the perioperative period were included. Treatment effect estimates were expressed as standardized mean differences (MDs) with confidence intervals, and heterogeneity was expressed as I2 values.

RESULTS

Seventy trials including 3402 participants were selected for the data synthesis. Exercise interventions significantly increased muscle mass (MD 0.62, 95 per cent c.i. 0.34 to 0.90; P < 0.001), muscle strength (MD 0.55, 0.39 to 0.71; P < 0.001), measures of gait speed (MD 0.42, 0.05 to 0.79; P = 0.03), and reduced time for completion of set exercises (MD -0.76, -1.12 to -0.40; P < 0.001) compared with controls. Subgroup analysis showed that interventions in the early postoperative period were more likely to have a positive effect on muscle mass (MD 0.71, 0.35 to 1.07; P < 0.001) and timed tests (MD -0.70, -1.10 to -0.30; P = 0.005) than preoperative interventions. Treatment effects on muscle mass (MD 0.09, -0.31 to 0.49; P = 0.66) and strength (MD 0.46, -0.01 to 0.92; P = 0.05) were attenuated by the presence of cancer. Results of analyses restricted to nine trials at low risk of allocation concealment bias and fourteen trials at low risk of attrition bias were comparable to those of the primary analysis. Risk-of-bias assessment showed that most trials were at high risk of incomplete outcome and attrition bias, thus reducing the estimate of certainty of the evidence according to the GRADE assessment tool.

CONCLUSION

Exercise interventions appear beneficial in reducing the impact of sarcopenia. Because of the high risk of bias and low certainty of the current evidence, large RCTs using standardized measures of muscle mass should be undertaken.

Minimally invasive versus conventional sternotomy for Mitral valve repair: protocol for a multicentre randomised controlled trial (UK Mini Mitral)

INTRODUCTION

Numbers of patients undergoing mitral valve repair (MVr) surgery for severe mitral regurgitation have grown and will continue to rise. MVr is routinely performed via median sternotomy; however, there is a move towards less invasive surgical approaches.There is debate within the clinical and National Health Service (NHS) commissioning community about widespread adoption of minimally invasive MVr surgery in the absence of robust research evidence; implementation requires investment in staff and infrastructure.The UK Mini Mitral trial will provide definitive evidence comparing patient, NHS and clinical outcomes in adult patients undergoing MVr surgery. It will establish the best surgical approach for MVr, setting a standard against which emerging percutaneous techniques can be measured. Findings will inform optimisation of cost-effective practice.

METHODS AND ANALYSIS

UK Mini Mitral is a multicentre, expertise based randomised controlled trial of minimally invasive thoracoscopically guided right minithoracotomy versus conventional sternotomy for MVr. The trial is taking place in NHS cardiothoracic centres in the UK with established minimally invasive mitral valve surgery programmes. In each centre, consenting and eligible patients are randomised to receive surgery performed by consultant surgeons who meet protocol-defined surgical expertise criteria. Patients are followed for 1 year, and consent to longer term follow-up.Primary outcome is physical functioning 12 weeks following surgery, measured by change in Short Form Health Survey (SF-36v2) physical functioning scale. Early and 1 year echo data will be reported by a core laboratory. Estimates of key clinical and health economic outcomes will be reported up to 5 years.The primary economic outcome is cost effectiveness, measured as incremental cost per quality-adjusted life year gained over 52 weeks following index surgery.

ETHICS AND DISSEMINATION

A favourable opinion was given by Wales REC 6 (16/WA/0156). Trial findings will be disseminated to patients, clinicians, commissioning groups and through peer reviewed publication.

TRIAL REGISTRATION NUMBER

ISRCTN13930454.