Effect of on-pump vs. off-pump coronary artery bypass grafting in patients with non-dialysis-dependent severe renal impairment: propensity-matched analysis from the UK registry dataset.

Introduction: On-pump coronary artery bypass (ONCABG) grafting in patients with a pre-existing poor renal reserve is known to carry significant morbidity and mortality. There is limited controversial evidence on the benefit of off-pump coronary artery bypass (OPCABG) grafting in these high-risk groups of patients. We compared early clinical outcomes in propensity-matched cohorts of patients with non-dialysis-dependent pre-operative severe renal impairment undergoing OPCABG vs. ONCABG, captured in a large national registry dataset. Methods: All data for patients with a pre-operative creatinine clearance of less than 50 mL/min who underwent elective or urgent isolated OPCABG or ONCABG from 1996 to 2019 were extracted from the UK National Adult Cardiac Surgery Audit (NACSA) database. Propensity score matching was performed using 1:1 nearest neighbor matching without replacement using several baseline characteristics. We investigated the effect of ONCABG vs. OPCABG in the matched cohort using cluster-robust standard error regression. Results: We identified 8,628 patients with severe renal impairment undergoing isolated CABG, of whom 1,142 (13.23%) underwent OPCABG during the study period. We compared 1,141 propensity-matched pairs of patients undergoing OPCABG vs. ONCABG. The median age of the matched population was 78 years in both groups, with no significant imbalance post-matching in the rest of the variables. There was no difference between OPCABG and ONCABG in in-hospital mortality rates, post-operative dialysis, and stroke rates. However, the return to theatre for bleeding or tamponade was higher in ONCABG vs. OPCABG (P > 0.02); however, OPCABG reduced the total length of stay in the hospital by 1 day (P = 0.008). After double adjustment in the matched population using cluster-robust standard regression, ONCABG did not increase mortality compared to OPCABG (OR, 1.05, P = 0.78), postoperative stroke (OR, 1.7, P = 0.12), and dialysis (OR, 0.7, P = 0.09); however, ONCABG was associated with an increased risk of bleeding (OR, 1.53, P = 0.03). Discussion: In this propensity analysis of a large national registry dataset, we found no difference in early mortality and stroke in patients with pre-operative severe renal impairment undergoing OPCABG or ONCABG surgery; however, ONCABG was associated with an increased risk of return to theatre for bleeding and an increased length of hospital stay.

Incidence and outcomes of surgical pulmonary embolectomy in the UK.

BACKGROUND: Surgical pulmonary embolectomy is rarely used for the treatment of massive acute pulmonary embolism. The aim of this study was to assess the incidence and outcomes of this operation by undertaking a retrospective analysis of a large national registry in the UK. METHODS: All acute pulmonary embolectomies performed between 1996 and 2018 were captured in the National Institute of Cardiovascular Outcomes Research central database. Trends in the number of operations performed during this interval and reported in-hospital outcomes were analysed retrospectively. Multivariable logistic regression was used to identify independent risk factors for in-hospital death. RESULTS: All 256 patients treated surgically for acute pulmonary embolism during the study interval were included in the analysis. Median age at presentation was 54 years, 55.9% of the patients were men, 48.0% had class IV heart failure symptoms, and 37.5% had preoperative cardiogenic shock. The median duration of bypass was 73 min, and median cross-clamp time was 19 min. Cardioplegic arrest was used in 53.1% of patients. The median duration of hospital stay was 11 days. The in-hospital mortality rate was 25%, postoperative stroke occurred in 5.4%, postoperative dialysis was required in 16%, and the reoperation rate for bleeding was 7.5%. Risk-adjusted multivariable analysis revealed cardiogenic shock (OR 2.54, 95% c.i. 1.05 to 6.21; P = 0.038), preoperative ventilation (OR 5.85, 2.22 to 16.35; P < 0.001), and duration of cardiopulmonary bypass exceeding 89 min (OR 7.82, 3.25 to 20.42; P < 0.001) as significant independent risk factors for in-hospital death. CONCLUSION: Surgical pulmonary embolectomy is rarely performed in the UK, and is associated with significant mortality and morbidity. Preoperative ventilation, cardiogenic shock, and increased duration of bypass were significant predictors of in-hospital death.

A blood clot in the lung can prevent the lungs from working properly and put pressure on the heart to work harder. Small clots can be treated with medications taken at home and are not a danger to life. Larger blood clots can put a lot of pressure on the heart and need immediate hospital treatment. Large blood clots can be treated with 'clot busting' medications, the delivery of a small tube into the blood vessels of the lung to suck up the clot or deliver medications directly on to its surface, and finally a form of open-heart surgery. With this surgery, a surgeon opens the chest, make a cut into the large vessels containing the clot, and physically removes the large piece of obstructing clot. The aim of this study was to describe and analyse the outcomes of this operation done in the UK over a long period. A database was used to find out how often and where this operation took place and its results. The available data were studied to try to understand how helpful this operation is to patients with lung blood clots. Between 1996 and 2018, 256 people had this operation. One in four patients did not survive the operation, 5.4% developed a clot or bleed in the brain, 16% needed to go on to a dialysis machine, and 7.5% had to be rushed back into theatre because of bleeding. Needing a ventilator machine for help with breathing, being in a sudden state of heart failure, and a long time on the heart bypass machine were all linked with patients who did not survive. This operation is rarely performed in the UK, and is often linked to a high chance of death or serious complication. In this study, the points described above were linked to a bad outcome.

Extracellular matrix stiffness controls cardiac fibroblast proliferation via the nuclear factor-Y (NF-Y) transcription factor.

The proliferative expansion of cardiac fibroblasts (CF) contributes towards cardiac fibrosis, which results in myocardial stiffening, cardiac dysfunction, and heart failure. CF sense and respond to increased stiffness of their local extracellular matrix, modulating their phenotype towards increased collagen synthesis and higher proliferation, leading potentially to a vicious circle of positive feedback. Here we describe a novel mechanism that mediates increased CF proliferation in response to a pathologically stiff Exteracellular matrix (ECM). The mechanism we describe is independent of the well-characterised mechano-sensitive transcript factors, YAP-TEAD and MKL1-SRF, which our data indicate are only responsible for part of the genes induced by stiffened ECM. Instead, our data identify Nuclear Factor-Y (NF-Y) as a novel mechanosensitive transcription factor, which mediates enhanced CF proliferation in response to a stiff ECM. We show that levels of NF-YA protein, the major regulatory subunit of NF-Y, and NF-Y transcriptional activity, are increased by a stiff ECM. Indeed, NF-Y activity drives the expression of multiple cell-cycle genes. Furthermore, NF-YA protein levels are dependent on FAK signalling suggesting a mechanistic link to ECM composition. Consistent with its role as a mechano-sensor, inhibition of NF-Y using siRNA or dominant negative mutant blocks CF proliferation on plastic in vitro, which models a stiff ECM, whereas ectopic expression of NF-YA increases the proliferation of cells interacting under conditions that model a physiologically soft ECM. In summary, our data demonstrate that NF-Y is a biomechanically sensitive transcription factor that promotes CF proliferation in a model of pathologically stiffened ECM.

Sex-Based Differences in Early Outcomes Following Mitral Valve Surgery for Degenerative Disease.

OBJECTIVES: To determine whether sex-based differences exist following surgery for degenerative mitral valve disease. METHODS: Using a national database, we analysed data on mitral valve surgery for degenerative disease (n = 22,658) between January 2000 and March 2019 in the UK. We split the cohort into men (n = 14,681) and women (n = 7977) and compared background characteristics, intraoperative variables and early postoperative outcomes. Our primary outcome was hospital mortality; secondary outcomes included re-exploration for bleeding, prolonged admission (>10 days) and mitral replacement. We used binary logistic regression models for all outcomes, with multiplicative interaction terms to determine the nature of any differences. RESULTS: Women presented older (70 ± 11 years vs. 67 ± 11 years, p < 0.001) with worse symptom profiles (New York Heart Association Class III-IV 57% vs. 44%, p < 0.001). They had higher rates of preoperative atrial fibrillation (39% vs. 35%, p < 0.001) and tricuspid disease requiring surgery (21% vs. 15%, p < 0.001). They had lower repair rates (66% vs. 76%, p < 0.001), higher mortality (3% vs. 2%, p < 0.001) and were more likely to have a prolonged admission (48% vs. 40%, p < 0.001). Female sex was an independent predictor of mortality (odds ratio (OR): 1.52, 95% CI: 1.21-1.90, p < 0.001). Age and Canadian Cardiovascular Society (CCS) score showed significant interactions with sex. The relationship between advancing age and mortality was found to be more pronounced in women. CONCLUSIONS: (1) Female sex is an independent predictor of hospital mortality, prolonged hospital admission and mitral valve replacement. (2) The relationship between female sex and mortality is exacerbated by worsening CCS score and advancing age. (3) Women have significantly lower repair rates.

Comparison of machine learning techniques in prediction of mortality following cardiac surgery: analysis of over 220 000 patients from a large national database.

OBJECTIVES: To perform a systematic comparison of in-hospital mortality risk prediction post-cardiac surgery, between the predominant scoring system-European System for Cardiac Operative Risk Evaluation (EuroSCORE) II, logistic regression (LR) retrained on the same variables and alternative machine learning techniques (ML)-random forest (RF), neural networks (NN), XGBoost and weighted support vector machine. METHODS: Retrospective analyses of prospectively routinely collected data on adult patients undergoing cardiac surgery in the UK from January 2012 to March 2019. Data were temporally split 70:30 into training and validation subsets. Mortality prediction models were created using the 18 variables of EuroSCORE II. Comparisons of discrimination, calibration and clinical utility were then conducted. Changes in model performance, variable-importance over time and hospital/operation-based model performance were also reviewed. RESULTS: Of the 227 087 adults who underwent cardiac surgery during the study period, there were 6258 deaths (2.76%). In the testing cohort, there was an improvement in discrimination [XGBoost (95% confidence interval (CI) area under the receiver operator curve (AUC), 0.834-0.834, F1 score, 0.276-0.280) and RF (95% CI AUC, 0.833-0.834, F1, 0.277-0.281)] compared with EuroSCORE II (95% CI AUC, 0.817-0.818, F1, 0.243-0.245). There was no significant improvement in calibration with ML and retrained-LR compared to EuroSCORE II. However, EuroSCORE II overestimated risk across all deciles of risk and over time. The calibration drift was lowest in NN, XGBoost and RF compared with EuroSCORE II. Decision curve analysis showed XGBoost and RF to have greater net benefit than EuroSCORE II. CONCLUSIONS: ML techniques showed some statistical improvements over retrained-LR and EuroSCORE II. The clinical impact of this improvement is modest at present. However the incorporation of additional risk factors in future studies may improve upon these findings and warrants further study.

A review and meta-analysis of conventional sternotomy versus minimally invasive mitral valve surgery for degenerative mitral valve disease focused on the last decade of evidence.

OBJECTIVES: Early meta-analyses comparing minimally invasive mitral valve surgery (MIMVS) with conventional sternotomy (CS) have determined the safety of MIMVS. We performed this review and meta-analysis based on studies from 2014 onwards to examine the differences in outcomes between MIMVS and CS. Specifically, some outcomes of interest included renal failure, new onset atrial fibrillation, mortality, stroke, reoperation for bleeding, blood transfusion and pulmonary infection. METHODS: A systematic search was performed in six databases for studies comparing MIMVS with CS. Although the initial search identified 821 papers in total, nine studies were suitable for the final analysis. All studies included compared CS with MIMVS. The Mantel - Haenszel statistical method was chosen due the use of inverse variance and random effects. A meta-analysis was performed on the data. RESULTS: MIMVS had significantly lower odds of renal failure (OR: 0.52; 95% CI 0.37 to 0.73, p < 0.001), new onset atrial fibrillation (OR: 0.78; 95% CI 0.67 to 0.90, p < 0.001), reduced prolonged intubation (OR: 0.50; 95% CI 0.29 to 0.87, p = 0.01) and reduced mortality (OR: 0.58; 95% CI 0.38 to 0.87, p < 0.01). MIMVS had shorter ICU stay (WMD: -0.42; 95% CI -0.59 to -0.24, p < 0.001) and shorter time to discharge (WMD: -2.79; 95% CI -3.86 to -1.71, p < 0.001). CONCLUSION: In the modern era, MIMVS for degenerative disease is associated with improved short-term outcomes when compared to the CS.

Mitral repair versus replacement: 20-year outcome trends in the UK (2000-2019).

OBJECTIVES: Using a large national database, we sought to describe outcome trends in mitral valve surgery between 2000 and 2019. METHODS: The study cohort was split into mitral valve repair (MVr) or replacement, including all patients regardless of concomitant procedures. Patients were grouped by four-year admission periods into groups (A to E). The primary outcome was in hospital mortality and secondary outcomes were return to theatre, postoperative stroke and postoperative length of stay. We investigated trends over time in patient demographics, comorbidities, intraoperative characteristics and postoperative outcomes. We used a multivariable binary logistic regression model to assess the relationship between mortality and time. Cohorts were further stratified by sex and aetiology. RESULTS: Of the 63 000 patients in the study cohort, 31 644 had an MVr and 31 356 had a replacement. Significant demographic shifts were observed. Aetiology has shifted towards degenerative disease; endocarditis rates in MVr dropped initially but are now rising (period A = 6%, period C = 4%, period E = 6%; P < 0.001). The burden of comorbidities has increased over time. In the latest time period, women had lower repair rates (49% vs 67%, P < 0.001) and higher mortality rates when undergoing repair (3% vs 2%, P = 0.001) than men. Unadjusted postoperative mortality dropped in MVr (5% vs 2%, P < 0.001) and replacement (9% vs 7%, P = 0.015). Secondary outcomes have improved. Time period was an independent predictor for reduced mortality in both repair (odds ratio: 0.41, 95% confidence interval: 0.28-0.61, P < 0.001) and replacement (odds ratio: 0.50, 95% confidence interval: 0.41-0.61, P < 0.001). CONCLUSIONS: In-hospital mortality has dropped significantly over time for mitral valve surgery in the UK. MVr has become the more common procedure. Sex-based discrepancies in repair rates and mortality require further investigation. Endocarditis rates in MVS are rising.

Consensus statement on aortic valve replacement via an anterior right minithoracotomy in the UK healthcare setting.

The wide uptake of anterior right thoracotomy (ART) as an approach for aortic valve replacement (AVR) has been limited despite initial reports of its use in 1993. Compared with median sternotomy, and even ministernotomy, ART is considered to be less traumatic to the chest wall and to help facilitate quicker patient recovery. In this statement, a consensus agreement is outlined that describes the potential benefits of the ART AVR. The technical considerations that require specific attention are described and the initiation of an ART programme at a UK centre is recommended through simulation and/or use of specialist instruments in conventional cases. The use of soft tissue retractors, peripheral cannulation, modified aortic clamping and the use of intraoperative adjuncts, such as sutureless valves and/or automated knot fasteners, are important to consider in order to circumvent the challenges of minimal the altered exposure via an ART.A coordinated team-based approach that encourages ownership of the programme by team members is critical. A designated proctor/mentor is also recommended. The organisation of structured training and simulation, as well as planning the initial cases are important steps to consider.

Propensity matched analysis of minimally invasive versus conventional isolated aortic valve replacement.

OBJECTIVE: To analyse the early and mid-term outcome of patients undergoing conventional aortic valve replacement (AVR) versus minimally invasive via hemi-sternotomy aortic valve replacement (MIAVR). METHODS: A single centre retrospective study involving 653 patients who underwent isolated aortic valve replacement (AVR) either via conventional AVR (n = 516) or MIAVR (n = 137) between August 2015 and March 2020. Using pre-operative characteristics, patients were propensity matched (PM) to produce 114 matched pairs. Assessment of peri-operative outcomes, early and mid-term survival and echocardiographic parameters was performed. RESULTS: The mean age of the PM conventional AVR group was 71.5 (±8.9) years and the number of male (n = 57) and female (n = 57) patients were equal. PM MIAVR group mean age was 71.1 (±9.5) years, and 47% of patients were female (n = 54) and 53% male (n = 60). Median follow-up for PM conventional AVR and MIAVR patients was 3.4 years (minimum 0, maximum 4.8 years) and 3.4 years (minimum 0, maximum 4.8 years), respectively. Larger sized aortic valve prostheses were inserted in the MIAVR group (median 23, IQR = 4) versus conventional AVR group (median 21, IQR = 2; p = 0.02, SMD = 0.34). Cardiopulmonary bypass (CPB) time was longer with MIAVR (94.4 ± 19.5 minutes) compared to conventional AVR (83.1 ± 33.3; p = 0.0001, SMD = 0.41). Aortic cross-clamp (AoX) time was also longer in MIAVR (71.6 ± 16.5 minutes) compared to conventional AVR (65.0 ± 52.8; p = 0.0001, SMD = 0.17). There were no differences in the early post-operative complications and mortality between the two groups. Follow-up echocardiographic data showed significant difference in mean aortic valve gradients between conventional AVR and MIAVR groups (17.3 ± 8.2 mmHg vs 13.0 ± 5.1 mmHg, respectively; p = 0.01, SMD = -0.65). There was no significant difference between conventional AVR and MIAVR in mid-term survival at 3 years (88.6% vs 92.1%; log-rank test p = 0.31). CONCLUSION: Despite the longer CPB and AoX times in the MIAVR group, there was no significant difference in early complications, mortality and mid-term survival between MIAVR and conventional AVR.

Network meta-analysis comparing blood cardioplegia, Del Nido cardioplegia and custodiol cardioplegia in minimally invasive cardiac surgery.

INTRODUCTION: Minimally invasive cardiac surgery has been evolving, with the intention of reducing surgical trauma, improve cosmesis and patient satisfaction. Single dose, crystalloid cardioplegia such as Del Nido cardioplegia and Custoidol solution have been increasingly used to reduce the interruption from repeating cardioplegia dosing to minimise the cardiopulmonary bypass and cross clamp time. However, the best cardioplegia for myocardial protection in adult minimally invasive cardiac surgery remains controversial. We aimed to conduct a meta-analysis to analyse the current evidence in the literature. METHOD: A systematic review and meta-analysis was performed following the updated 2020 PRISMA guideline. Articles published in the five major electronic databases up 1st of April 2021 were identified and reviewed. The primary outcome was in-hospital or 30-day mortality. Traditional pairwise and Bayesian network meta-analyses were conducted. RESULTS: Nine articles were included in this study. The use of Del Nido cardioplegia was associated with a lower volume of cardioplegia used (Del Nido vs Blood, 1105.62 mL+/-123.47 vs 2569.46 mL+/-1515.52, p<0.001), cardiopulmonary bypass (Del Nido vs Custoidol vs Blood: 91.67+/-14.78 vs 138.05 +/- 21.30 vs 119.38+/-26.91 minutes, p<0.001) and cross-clamp time (Del Nido vs Custoidol vs Blood: 74.99+/-18.55 vs 82.01 +/- 17.28 vs 93.66+/-8.88 minutes, p < 0.001). No differences were observed in the incidence of in-hospital/30-day mortality rate, new onset of atrial fibrillation and stroke. Ranking analysis showed the Custoidol solution has the highest probability to be the first ranked cardioplegia. CONCLUSION: No differences were found between blood and crystalloid cardioplegia in adult minimally invasive cardiac surgery in several clinical outcomes. The cardioplegia of choice in minimally invasive cardiac surgery remains the surgeons' decision and preference.

Early mortality and neurologic outcomes following mitral valve surgery in the very elderly.

OBJECTIVES: Valve repair is the gold standard for treatment of degenerative mitral valve disease. As the population ages, patients undergoing valve degeneration and therefore considered for mitral valve surgery will naturally be getting older. We sought to evaluate whether mitral repair retained a survival advantage over replacement in patients ≥80 years old. METHODS: A retrospective cohort study was performed using data acquired from the United Kingdom National Adult Cardiac Surgery Audit for the outcomes of in-hospital mortality and postoperative cerebrovascular event (CVA). Individual multivariable logistic regression models were created to investigate adjusted associations between these outcomes and type of mitral valve operation, repair or replacement. Additionally, associations between the individual model parameters and in-hospital mortality and CVA were investigated. RESULTS: A total of 1140 patients underwent mitral repair (66.4%, median age 82.3), and 577 patients underwent mitral replacement (33.6%, median age 82.1). The overall age range was 80-92. The incidence of in-hospital mortality favored the repair group (4.4% vs. 8.3%, p = .001). Multivariable logistic regression modeling demonstrated an increased adjusted odds of in-hospital mortality for mitral valve replacement (MVR) (odd ratio [OR]: 2.01, 1.15-3.50, p = .01). The only other parameter associated with an increased adjusted odds of in-hospital mortality was postoperative dialysis (OR: 14.2, 7.67-26.5, p < .001). There was not a demonstrated association between MVR and perioperative CVA (OR: 1.11, 0.49-2.4, p = .8). CONCLUSIONS: In patients ≥80 years old, mitral valve repair (MVr) was shown to be associated with a decreased adjusted odds of mortality, with a null association with CVA. These results suggest that, if feasible, MVr should remain the preferred management strategy, even in the very elderly.

Surgical outcomes and optimal approach to treatment of aortic valve endocarditis with aortic root abscess - systematic review and meta-analysis.

BACKGROUND: Data on the postoperative outcomes for patients with infective endocarditis complicated by an aortic root abscess is sparse due to the condition's low incidence and high mortality rates. This systematic review and meta-analysis aims to evaluate existing data on the impact of aortic root abscesses on the postoperative outcomes and to inform optimal surgical approach. METHODS: The online databases MEDLINE, EMBASE and Cochrane library were searched from 1990 to 2022 for studies comparing cohorts of surgically managed infective endocarditis patients with and without an aortic root abscess. Data was extracted by two independent investigators and aggregated in a random-effects model. Risk of bias was assessed using an adapted version of the Newcastle-Ottawa scale. RESULTS: Six clinical studies were included in the meta-analysis (n 1982). The abscess group was associated with increased in-hospital mortality (OR 1.74 95%: CI 1.18-2.56) and late mortality (HR 1.27 95% CI:1.03-1.58). The reoperation meta-analysis was complicated by high rates of heterogeneity (I2 = 59%) and found no significant differences in reoperation between abscess and no abscess groups (HR=1.48: 95% CI:0.92-2.40). Post-hoc scatter graph showed a strong linear relationship (r 0.998), suggesting hospitals with higher rates of aortic root replacement achieve lower rates of reoperation for aortic root abscess patients compared with patch reconstruction. CONCLUSIONS: The presence of an aortic root abscess in aortic valve endocarditis is associated with elevated early and late mortality despite modern standards of care. Additionally, aortic root replacement should be considered to have a favourable postoperative profile for use in this context.

Surgical outcomes and optimal approach to treatment of aortic valve endocarditis with aortic root abscess.

OBJECTIVES: To evaluate the impact of aortic root abscess (ARA) on the postoperative outcomes of surgically managed infective endocarditis (IE) and to inform optimal surgical approach. METHODS: Between 2009 and 2020, 143 consecutive patients who underwent surgical management for aortic-valve IE were included in a retrospective cohort study. Multivariable and propensity-weighted analyses were used to adjust for demographic imbalances between those without (n = 93; NARA) and with an ARA (n = 50). Additionally, empirical subgroup analysis appraised the two most used surgical techniques; patch reconstruction (PR) and aortic root replacement (ARR). RESULTS: Demographic characteristics were similar between ARA and NARA except for logistic EuroSCORE, previous valve surgery, and multivalvular infection. In-hospital mortality was 8% and 12% in NARA and ARA, respectively (p = .38), with mortality rates consistently nonsignificantly higher in ARA across all time periods. The overall reoperation rate was also higher in ARA (27% vs. 14%; p = .09) and ARA was shown to be associated with late reoperation (odds ratio [OR] = 2.74; 95% confidence interval [CI] = 1.18-6.36). Patients treated with an ARR showed a 16% increase in late mortality when compared with PR (40% vs. 24%; p = .27) and a 17% lower reoperation rate (14% vs. 31%; p = .24). Propensity-weighted analysis identified ARR as a significant protective factor for reoperation (hazard ratio = 0.05; 95% CI = 0.01-0.34). CONCLUSIONS: The presence of an ARA in aortic valve endocarditis was not associated with significantly higher early and late mortality but is linked with a higher reoperation rate at our institution. ARR in ARA is protective from reoperation so should be considered best practice in this setting.

Minimally invasive versus transcatheter closure of secundum atrial septal defects: a systematic review and meta-analysis.

BACKGROUND: Limited data exists demonstrating the efficacy of minimally invasive surgery (MIS) compared to transcatheter (TC) closure of atrial septal defects (ASD). This systematic review and meta-analysis aims to compare post-operative outcomes of MIS versus TC repair in ASD closure. METHODS: PubMed, Medline and EMBASE were searched from inception until June 2018 for randomised and observational studies comparing post-operative outcomes for MIS and TC repair. The studies were reviewed for bias using the ROBINS-I Score and pooled in a meta-analysis using STATA (version 15). RESULTS: Six observational studies, involving 1524 patients assessing three primary and five secondary outcomes were included. Evidence suggests TC repair yielded shorter hospital stay (MD = 3.32, 95% CI 1.04-5.60) and lower rates of transient atrial fibrillation (AF) (RR = 0.48, 95% CI 0.20-1.15). TC repair patients also had fewer pericardial effusions (RR = 0.27, 95% CI 0.05-1.54, I2 = 0.0%) and pneumothoraxes (RR = 0.18, 95% CI 0.04-0.80, I2 = 0.0%). However, TC repair results in more minor residual shunts (RR = 6.04, 95% CI 1.69-21.63 in favour of MIS, I2 = 39.0%). No differences were found for incidences of strokes (RR = 1.58, 95% CI 0.23-10.91, I2 = 19.3%), unexpected bleeding (RR = 0.44, 95% CI 0.19-1.04, I2 = 0.0%) and blood transfusion (RR = 0.39, 95% CI 0.09-1.59, I2 = 0.0%). CONCLUSIONS: MIS closure for ASD has similar outcomes compared to TC repair. However, the lack of randomised literature related to MIS versus TC repair for ASD closure warrants further evidence in the form of RCTs to further support these findings.

In search of optimal cardioplegia for minimally invasive valve surgery.

Cardioplegic solutions are used in cardiac surgery to achieve controlled cardiac arrest during operations, making surgery safer. Cardioplegia can either be blood or crystalloid based, with perceived pros and cons of each type. Whilst it is known that cardioplegia causes cardiac arrest, there is debate over which cardioplegic solution provides the highest degree of myocardial protection during arrest. Myocardial damage is measured post-operatively by biomarkers such as serum TnT, TnI or CK-MB. It is known that the outcomes of minimally invasive valve surgery are comparable to full sternotomy valve operations. Despite there being a wide diversity in use of different cardioplegic solutions across the world, this comprehensive literature review found no superiority of one cardioplegic solution over the other for myocardial protection during minimally invasive valve procedures.

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.

The ongoing impact of COVID-19 on adult cardiac surgery and suggestions for safe continuation throughout the pandemic: a review of expert opinions.

OBJECTIVES: To establish the impact of the COVID-19 pandemic on adult cardiac surgery by reviewing current data and use this to establish methods for safely continuing to carry out surgery. METHODS: Conduction of a literature search via PubMed using the search terms: '(adult cardiac OR cardiothoracic OR surgery OR minimally invasive OR sternotomy OR hemi-sternotomy OR aortic valve OR mitral valve OR elective OR emergency) AND (COVID-19 or coronavirus OR SARS-CoV-2 OR 2019-nCoV OR 2019 novel coronavirus OR pandemic)'. Thirty-two articles were selected. RESULTS: Cardiac surgery patients have an increased risk of complications from COVID-19 and require vital finite resources such as intensive care beds, also required by COVID-19 patients. Thus reducing their admission and potential hospital-acquired infection with COVID-19 is paramount. During the peak, only emergencies such as acute aortic dissections were treated, triaging patients according to surgical priority and cancelling all elective procedures. Screening and 2-week quarantine prior to admission were essential changes, alongside additional levels of PPE. Focus was on reducing length of stay and switching to day-cases to reduce post-operative transmission risk, whilst several hospitals adopted 'hot' and 'cold' operating theatres for covid-confirmed and covid-negative patients. CONCLUSIONS: This paper suggests a 'CARDIO' approach for reintroducing elective procedures: 'Care, Assess, Re-Evaluate, Develop, Implement, Overcome'; prioritising the mental and physical health of the workforce, learning from and sharing experiences and objectively prioritising patients to improve case load.

Current Perspectives on Contemporary Rheumatic Mitral Valve Repair.

The surgical management of rheumatic mitral valve disease remains a challenge for cardiac surgeons. Durability of mitral valve repair (MVr) is likely compromised not simply due to high technical demand, but surgeon reluctance, despite boasting copious advantages over MV replacement. This comprehensive review aims to evoke a deeper understanding of MVr concepts necessary to abate these limitations and shift mindset towards a more holistic approach to repair. Details of commonly utilized techniques in contemporary MVr for rheumatic heart disease will be discussed. Of importance, the reparative procedures will be mapped to an in-depth physiological exploration of the mitral complex-dynamism and rheumatic interplay. This is further emphasized by outlining the current "aggressive" resection strategy in contemporary rheumatic MVr.

Systematic review and meta-analysis of mortality risk prediction models in adult cardiac surgery.

OBJECTIVES: The most used mortality risk prediction models in cardiac surgery are the European System for Cardiac Operative Risk Evaluation (ES) and Society of Thoracic Surgeons (STS) score. There is no agreement on which score should be considered more accurate nor which score should be utilized in each population subgroup. We sought to provide a thorough quantitative assessment of these 2 models. METHODS: We performed a systematic literature review and captured information on discrimination, as quantified by the area under the receiver operator curve (AUC), and calibration, as quantified by the ratio of observed-to-expected mortality (O:E). We performed random effects meta-analysis of the performance of the individual models as well as pairwise comparisons and subgroup analysis by procedure type, time and continent. RESULTS: The ES2 {AUC 0.783 [95% confidence interval (CI) 0.765-0.800]; O:E 1.102 (95% CI 0.943-1.289)} and STS [AUC 0.757 (95% CI 0.727-0.785); O:E 1.111 (95% CI 0.853-1.447)] showed good overall discrimination and calibration. There was no significant difference in the discrimination of the 2 models (difference in AUC -0.016; 95% CI -0.034 to -0.002; P = 0.09). However, the calibration of ES2 showed significant geographical variations (P < 0.001) and a trend towards miscalibration with time (P=0.057). This was not seen with STS. CONCLUSIONS: ES2 and STS are reliable predictors of short-term mortality following adult cardiac surgery in the populations from which they were derived. STS may have broader applications when comparing outcomes across continents as compared to ES2. REGISTRATION: Prospero (https://www.crd.york.ac.uk/PROSPERO/) CRD42020220983.