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.

Limited versus full sternotomy for aortic valve replacement.

BACKGROUND: Aortic valve disease is a common condition easily treatable with cardiac surgery. This is conventionally performed by opening the sternum ('median sternotomy') and replacing the valve under cardiopulmonary bypass. Median sternotomy is well tolerated, but as less invasive options become available, the efficacy of limited incisions has been called into question. In particular, the effects of reducing the visibility and surgical access have raised safety concerns with regard to the placement of cannulae, venting of the heart, epicardial wire placement, and de-airing of the heart at the end of the procedure. These difficulties may increase operating times, affecting outcome. The benefits of smaller incisions are thought to include decreased pain; improved respiratory mechanics; reductions in wound infections, bleeding, and need for transfusion; shorter intensive care stay; better cosmesis; and a quicker return to normal activity. This is an update of a Cochrane review first published in 2017, with seven new studies. OBJECTIVES: To assess the effects of minimally invasive aortic valve replacement via a limited sternotomy versus conventional aortic valve replacement via median sternotomy in people with aortic valve disease requiring surgical replacement. SEARCH METHODS: We performed searches of CENTRAL, MEDLINE and Embase from inception to August 2021, with no language limitations. We also searched two clinical trials registries and manufacturers' websites. We reviewed references of primary studies to identify any further studies of relevance. SELECTION CRITERIA: We included randomised controlled trials comparing aortic valve replacement via a median sternotomy versus aortic valve replacement via a limited sternotomy. We excluded trials that performed other minimally invasive incisions such as mini-thoracotomies, port access, transapical, transfemoral or robotic procedures. Although some well-conducted prospective and retrospective case-control and cohort studies exist, these were not included in this review. DATA COLLECTION AND ANALYSIS: Two review authors independently assessed trial papers to extract data, assess quality, and identify risk of bias. A third review author provided arbitration where required. We determined the certainty of evidence using the GRADE methodology and summarised results of patient-relevant outcomes in a summary of findings table. MAIN RESULTS: The review included 14 trials with 1395 participants. Most studies had at least two domains at high risk of bias. We analysed 14 outcomes investigating the effects of minimally invasive limited upper hemi-sternotomy on aortic valve replacement as compared to surgery performed via full median sternotomy. Upper hemi-sternotomy may have little to no effect on mortality versus full median sternotomy (risk ratio (RR) 0.93, 95% confidence interval (CI) 0.45 to 1.94; 10 studies, 985 participants; low-certainty evidence). Upper hemi-sternotomy for aortic valve replacement may increase cardiopulmonary bypass time slightly, although the evidence is very uncertain (mean difference (MD) 10.63 minutes, 95% CI 3.39 to 17.88; 10 studies, 1043 participants; very low-certainty evidence) and may increase aortic cross-clamp time slightly (MD 6.07 minutes, 95% CI 0.79 to 11.35; 12 studies, 1235 participants; very low-certainty evidence), although the evidence is very uncertain. Most studies had at least two domains at high risk of bias. Postoperative blood loss was probably lower in the upper hemi-sternotomy group (MD -153 mL, 95% CI -246 to -60; 8 studies, 767 participants; moderate-certainty evidence). Low-certainty evidence suggested that there may be no change in pain scores by upper hemi-sternotomy (standardised mean difference (SMD) -0.19, 95% CI -0.43 to 0.04; 5 studies, 649 participants). Upper hemi-sternotomy may result in little to no difference in quality of life (MD 0.03 higher, 95% CI 0 to 0.06 higher; 4 studies, 624 participants; low-certainty evidence). Two studies reporting index admission costs concluded that limited sternotomy may be more costly at index admission in the UK National Health Service (MD 1190 GBP more, 95% CI 420 GBP to 1970 GBP, 2 studies, 492 participants; low-certainty evidence). AUTHORS' CONCLUSIONS: The evidence was of very low to moderate certainty. Sample sizes were small and underpowered to demonstrate differences in some outcomes. Clinical heterogeneity was also noted. Considering these limitations, there may be little to no effect on mortality. Differences in extracorporeal support times are uncertain, comparing upper hemi-sternotomy to full sternotomy for aortic valve replacement. Before widespread adoption of the minimally invasive approach can be recommended, there is a need for a well-designed and adequately powered prospective randomised controlled trial. Such a study would benefit from also performing a robust cost analysis. Growing patient preference for minimally invasive techniques merits thorough quality of life analyses to be included as end points, as well as quantitative measures of physiological reserve.

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.

Determinants of outcomes following surgery for type A acute aortic dissection: the UK National Adult Cardiac Surgical Audit.

AIMS: Operability of type A acute aortic dissections (TAAAD) is currently based on non-standardized decision-making process, and it lacks a disease-specific risk evaluation model that can predict mortality. We investigated patient, intraoperative data, surgeon, and centre-related variables for patients who underwent TAAAD in the UK. METHODS AND RESULTS: We identified 4203 patients undergoing TAAAD surgery in the UK (2009-18), who were enrolled into the UK National Adult Cardiac Surgical Audit dataset. The primary outcome was operative mortality. A multivariable logistic regression analysis was performed with fast backward elimination of variables and the bootstrap-based optimism-correction was adopted to assess model performance. Variation related to hospital or surgeon effects were quantified by a generalized mixed linear model and risk-adjusted funnel plots by displaying the individual standardized mortality ratio against expected deaths. Final variables retained in the model were: age [odds ratio (OR) 1.02, 95% confidence interval (CI) 1.02-1.03; P < 0.001]; malperfusion (OR 1.79, 95% CI 1.51-2.12; P < 0.001); left ventricular ejection fraction (moderate: OR 1.40, 95% CI 1.14-1.71; P = 0.001; poor: OR 2.83, 95% CI 1.90-4.21; P < 0.001); previous cardiac surgery (OR 2.29, 95% CI 1.71-3.07; P < 0.001); preoperative mechanical ventilation (OR 2.76, 95% CI 2.00-3.80; P < 0.001); preoperative resuscitation (OR 3.36, 95% CI 1.14-9.87; P = 0.028); and concomitant coronary artery bypass grafting (OR 2.29, 95% CI 1.86-2.83; P < 0.001). We found a significant inverse relationship between surgeons but not centre annual volume with outcomes. CONCLUSIONS: Patient characteristics, intraoperative factors, cardiac centre, and high-volume surgeons are strong determinants of outcomes following TAAAD surgery. These findings may help refining clinical decision-making, supporting patient counselling and be used by policy makers for quality assurance and service provision improvement.

A survey of minimally invasive cardiac surgery during the COVID-19 pandemic.

BACKGROUND: Lack of scientific data on the feasibility and safety of minimally invasive cardiac surgery (MICS) during the COVID-19 pandemic has made clinical decision making challenging. This survey aimed to appraise MICS activity in UK cardiac units and establish a consensus amongst front-line MICS surgeons regarding standard best MICS practise during the pandemic. METHODS: An online questionnaire was designed through the 'googleforms' platform. Responses were received from 24 out of 28 surgeons approached (85.7%), across 17 cardiac units. RESULTS: There was a strong consensus against a higher risk of conversion from minimally invasive to full sternotomy (92%; n = 22) nor there is increased infection (79%; n = 19) or bleeding (96%; n = 23) with MICS compared to full sternotomy during the pandemic. The majority of respondents (67%; n = 16) felt that it was safe to perform MICS during COVID-19, and that it should not be halted (71%; n = 17). London cardiac units experienced a decrease in MICS (60%; n = 6), whereas non-London units saw no reduction. All London MICS surgeons wore an FP3 mask compared to 62% (n = 8) of non-London MICS surgeons, 23% (n = 3) of which only wore a surgical mask. London MICS surgeons felt that routine double gloving should be done (60%; n = 6) whereas non-London MICS surgeons held a strong consensus that it should not (92%; n = 12). CONCLUSION: Whilst more robust evidence on the effect of COVID-19 on MICS is awaited, this survey provides interesting insights for clinical decision-making regarding MICS and aids to facilitate the development of standardised MICS guidelines for an effective response during future pandemics.

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.

Does Blood Transfusion Have an Effect on Outcomes After Aortic Valve Replacement Surgery?

OBJECTIVE: Long-term outcomes following surgical aortic valve replacement (AVR) are excellent. However, there is a significant early morbidity burden. Red cell transfusion is common in the perioperative period and deleterious effects of receiving a transfusion on early postoperative morbidity are well described in observational studies. This study aimed to assess the effect of transfusion on ischaemic or infective outcomes after aortic valve replacement. METHODS: Data from 270 patients enrolled in the Manubrium-limited ministernotomy versus conventional sternotomy for aortic valve replacement (MAVRIC) randomised controlled trial was used to create two cohorts, patients that received red cell transfusions following AVR and those that did not. Propensity score matching was performed to limit the effect of confounding variables. Strict transfusion thresholds were maintained, with patients receiving a transfusion if haemoglobin concentration fell below 80 g/L, or if significant bleeding or haemodynamic instability occurred. The primary outcome was a composite of ischaemic event (myocardial infarction, permanent stroke, gut ischaemia or acute kidney injury) or serious infection (sepsis, endocarditis, respiratory tract or wound infection). Patients were followed for 12 weeks following surgery. RESULTS: Sixty-three (63) of 270 patients received a red cell transfusion (23.3%). Transfused patients had significantly lower body mass index (BMI), a higher proportion of females, a lower preoperative haemoglobin and haematocrit, a higher EuroSCORE II score, worse renal function and were more likely to have undergone urgent surgery compared to the unadjusted control cohort. Once matched, there was no difference in the primary outcome between cohorts. There was a significantly increased length of hospital stay in the transfused group (median 7 days transfused, median 5 days not-transfused, p=0.001). CONCLUSIONS: Red cell transfusion, using a transfusion threshold of 80 g/L, does not appear to be associated with adverse ischaemic or infective outcomes after aortic valve replacement.

Early and Late Outcomes After Minimally Invasive Mitral Valve Repair Surgery.

BACKGROUND AND AIM OF THE STUDY: The practice of thoracoscopic assisted minimally invasive mitral valve repair surgery is less common in the United Kingdom than in Europe or the USA. The main reasons for this are concerns around increased operative risk, feasibility and durability of valve repair. The study aim was to report the early and late outcomes of minimally invasive mitral valve repair surgery at a single U.K. center. METHODS: Patients undergoing isolated minimally invasive mitral valve repair between 2003 and 2013 were reviewed retrospectively. Data were obtained from a prospectively maintained institutional database, a comprehensive review of individual case notes, echocardiograms, intensive care charts, clinic letters, discharge summaries, and the authors' follow up database (based on data supplied by the UK Office for National Statistics). RESULTS: A total of 190 patients (mean age 61 years; mean EuroSCORE 3.9) underwent the procedure. The mean cardiopulmonary bypass and aortic cross-clamp times were 153 and 108 min, respectively. Rates of major postoperative complications were: reoperation for bleeding 3.7%, stroke 1.6%, intra-aortic balloon pump 2.1%, and venovenous hemofiltration 2.6%. The median intensive care stay was one day, and the median hospital stay five days (21.8% of patients were discharged by day 3). The 30-day mortality was 1.1% (n = 2). Echocardiography performed at discharge or six weeks postoperatively showed less than mild mitral regurgitation (MR) in 91.3%. The median duration of follow up was 57 months. During the entire follow up period, four patients (2.1%) underwent repeat surgery for recurrent MR (between 15 months and five years). Of 188 patients discharged from hospital, nine (4.8%) died during follow up: median 5.3 years (range 1.3- 10.7 years) post surgery. CONCLUSION: These data are the first from the U.K. demonstrating early and late outcomes after thoracoscopic assisted minimally invasive mitral valve repair surgery. The data establish the safety and efficacy of the technique and, importantly, lend further support towards a prospective randomized comparison of minimally invasive versus conventional mitral valve repair surgery.

Feasibility study of rehabilitation for cardiac patients aided by an artificial intelligence web-based programme: a randomised controlled trial (RECAP trial)-a study protocol.

INTRODUCTION: Cardiac rehabilitation (CR) delivered by rehabilitation specialists in a healthcare setting is effective in improving functional capacity and reducing readmission rates after cardiac surgery. It is also associated with a reduction in cardiac mortality and recurrent myocardial infarction. This trial assesses the feasibility of a home-based CR programme delivered using a mobile application (app). METHODS: The Rehabilitation through Exercise prescription for Cardiac patients using an Artificial intelligence web-based Programme (RECAP) randomised controlled feasibility trial is a single-centre prospective study, in which patients will be allocated on a 1:1 ratio to a home-based CR programme delivered using a mobile app with accelerometers or standard hospital-based rehabilitation classes. The home-based CR programme will employ artificial intelligence to prescribe exercise goals to the participants on a weekly basis. The trial will recruit 70 patients in total. The primary objectives are to evaluate participant recruitment and dropout rates, assess the feasibility of randomisation, determine acceptability to participants and staff, assess the rates of potential outcome measures and determine hospital resource allocation to inform the design of a larger randomised controlled trial for clinical efficacy and health economic evaluation. Secondary objectives include evaluation of health-related quality of life and 6 minute walk distance. ETHICS AND DISSEMINATION: RECAP trial received a favourable outcome from the Berkshire research ethics committee in September 2022 (IRAS 315483).Trial results will be made available through publication in peer-reviewed journals and presented at relevant scientific meetings. TRIAL REGISTRATION NUMBER: ISRCTN97352737.

Antithrombotic therapy after heart valve surgery: contemporary practice in the UK.

OBJECTIVES: There is a lack of high-quality data informing the optimal antithrombotic drug strategy following bioprosthetic heart valve replacement or valve repair. Disparity in recommendations from international guidelines reflects this. This study aimed to document current patterns of antithrombotic prescribing after heart valve surgery in the UK. METHODS: All UK consultant cardiac surgeons were e-mailed a custom-designed survey. The use of oral anticoagulant (OAC) and/or antiplatelet drugs following bioprosthetic aortic valve replacement or mitral valve replacement, or mitral valve repair (MVrep), for patients in sinus rhythm, without additional indications for antithrombotic medication, was assessed. Additionally, we evaluated anticoagulant choice following MVrep in patients with atrial fibrillation. RESULTS: We identified 260 UK consultant cardiac surgeons from 36 units, of whom 103 (40%) responded, with 33 units (92%) having at least 1 respondent. The greatest consensus was for patients undergoing bioprosthetic aortic valve replacement, in which 76% of surgeons favour initial antiplatelet therapy and 53% prescribe lifelong treatment. Only 8% recommend initial OAC. After bioprosthetic mitral valve replacement, 48% of surgeons use an initial OAC strategy (versus 42% antiplatelet), with 66% subsequently prescribing lifelong antiplatelet therapy. After MVrep, recommendations were lifelong antiplatelet agent alone (34%) or following 3 months OAC (20%), no antithrombotic agent (20%), or 3 months OAC (16%). After MVrep for patients with established atrial fibrillation, surgeons recommend warfarin (38%), a direct oral anticoagulant (37%) or have no preference between the 2 (25%). CONCLUSIONS: There is considerable variation in the use of antithrombotic drugs after heart valve surgery in the UK and a lack of high-quality evidence to guide practice, underscoring the need for randomized studies.