Thoracic surgery in patients on veno-venous extracorporeal membrane oxygenation for COVID-19 associated acute respiratory distress syndrome.

OBJECTIVES: The COVID-19 pandemic has generated a new type of acute respiratory distress syndrome (ARDS) arising as a complication of COVID-19 pneumonia. Extreme cases require the support of extracorporeal membrane oxygenation (ECMO). Here we present the outcomes of patients that underwent surgical tracheostomy or thoracic surgery at a single tertiary centre whilst on ECMO support for COVID-19 related ARDS. METHODS: 18 patients requiring thoracic input whilst on ECMO support during the first wave of COVID-19 (March-June 2020) were included. Thoracic surgery was required both for performing surgical tracheostomies in the operating theatre and for treating emergencies arising under the ECMO treatment such as bleeding complications. RESULTS: Thirteen patients underwent a surgical tracheostomy, whilst five patients had an invasive thoracic procedure. Anticoagulation was withheld for at least 12 h in the perioperative setting regardless of the indication. One patient was re-operated for haemothorax immediately after the end of the primary operation. 94.5% of the patients were successfully decannulated from ECMO support. Overall 30-day mortality in the cohort was 5.5% (1/18). CONCLUSIONS: Thoracic surgeons can play a valuable role in supporting an ECMO unit during the COVID pandemic, by treating ECMO related complications and by safely performing surgical tracheostomies. Withholding anticoagulation in the perioperative window was not associated with increased thromboembolic events and is desirable when interventions or surgery is indicated in this patient cohort to avoid excessive bleeding.

Predictors of outcome after CABG in the South-Asian community: a propensity matched analysis.

BACKGROUND: Ethnicity is not incorporated into standardized pre-operative risk-stratification tools for cardiac surgery. This study compared short-term outcomes following coronary artery bypass graft (CABG) surgery in South Asian and non-Asian patients. METHODS: Consecutive patients undergoing isolated CABG surgery via sternotomy between the years 2011 and 2019 were retrospectively analyzed. Initially, 1957 patients were identified (799 South-Asian, 40.8%). The patient groups were then propensity matched according to 10 relevant pre-operative covariates (age, body mass index, pulmonary disease, renal failure, smoking, diabetes, ventricular function, renal failure): 675 non-Asian patients were matched against 675 Asian patients. RESULTS: Operative mortality was 1.77% and similar between the two groups (p = 0.447). Multivariate regression analysis found predictors of operative mortality to be pre-operative serum creatinine, age, left ventricular (LV) impairment, and extent of coronary disease. The effect of creatinine on mortality was selective for South-Asian patients (p = 0.015). LV impairment was a predictor of mortality in non-Asian patients, however this effect did not exist in South-Asian patients. Predictors of short-term complications (composite of death, stroke, reoperation, hemofiltration, and pneumonia) were age and creatinine (coefficient 0.002, 95% CI 0.0004-0.004, p = 0.019) in the overall cohort. Subgroup analysis found age to remain a selective negative predictor of complications in South-Asian patients. Cox regression analysis found creatinine, age, and LVEF to influence 10-year survival, whilst ethnicity was not a predictor. CONCLUSION: This study highlights the cumulative risk associated with ethnicity and renal disease in predicting short-term outcomes following CABG. This warrants further investigations in larger populations, thus guiding pre-operative risk-stratification.

Comparison of outcomes between aortic root replacement and supra-coronary interposition graft for type A aortic dissection: A retrospective case series.

BACKGROUND: The decision to conserve or replace the native aortic valve following acute type-A aortic dissection (ATAAD) is an area of cardiac surgery without standardized practice. This single-center retrospective study analysed the long-term performance of the native aortic valve and root following surgery for ATAAD. METHODS: Between 2009 and 2018 all cases ATAAD treated at Royal Brompton and Harefield NHS Foundation Trust were analysed. Patients were divided into two groups: (a) ascending aorta (interposition) graft (AAG) without valve replacement and (b) nonvalve-sparing aortic root replacement (ARR). Preoperative covariates were compared, as well as operative characteristics and postoperative complications. Long-term survival and echocardiographic outcomes were analysed using regression analysis. RESULTS: In total, 116 patients were included: 63 patients in the AAG group and 53 patients in the ARR group. In patients where the native aortic valve was conserved, nine developed severe aortic regurgitation and two patients developed dilation of the aortic root requiring subsequent replacement during the follow-up period. Aortic regurgitation at presentation was not found to be associated with subsequent risk of developing severe aortic regurgitation or reintervention on the aortic valve. Overall mortality was observed to be significantly lower in patients undergoing AAG (17.5% vs. 41.5%, p = .004). CONCLUSIONS: With careful patient selection, the native aortic root shows good long-term durability both in terms of valve competence and stable root dimensions after surgery for ATAAD. This study supports the consideration of conservation of the aortic valve during emergency surgery for type-A dissection, in the absence of a definitive indication for root replacement, including in cases where aortic regurgitation complicates the presentation.

Type-A acute aortic dissection complicated by parenchymal hemorrhagic stroke: Timing of surgery for a rare presentation of aortic dissection.

Acute type-A aortic dissection is a rare but life-threatening cardiac surgery emergency. Immediate operative management is important to give patients the best chance of survival. However, where an aortic dissection is complicated by a concurrent hemorrhagic stroke the risks of precipitating a catastrophic intracranial hemorrhage during surgery must be balanced against the risk of aortic rupture. The optimal timing of surgery in this rare presentation of type-A aortic dissection is unknown. In this case report we describe a 67-year-old gentleman who initially presented with neurological symptoms, and was diagnosed with an acute intracerebral hemorrhage, but was subsequently also diagnosed with an acute type-A aortic dissection. He proceeded to have a successful tissue aortic root replacement, total arch replacement with zone two frozen elephant trunk implantation 4 weeks after his initial diagnosis.

Six Month Mortality in Patients with COVID-19 and Non-COVID-19 Viral Pneumonitis Managed with Veno-Venous Extracorporeal Membrane Oxygenation.

A significant proportion of patients with COVID-19 develop acute respiratory distress syndrome (ARDS) with high risk of death. The efficacy of veno-venous extracorporeal membrane oxygenation (VV-ECMO) for COVID-19 on longer-term outcomes, unlike in other viral pneumonias, is unknown. In this study, we aimed to compare the 6 month mortality of patients receiving VV-ECMO support for COVID-19 with a historical viral ARDS cohort. Fifty-three consecutive patients with COVID-19 ARDS admitted for VV-ECMO to the Royal Brompton Hospital between March 17, 2020 and May 30, 2020 were identified. Mortality, patient characteristics, complications, and ECMO parameters were then compared to a historical cohort of patients with non-COVID-19 viral pneumonia. At 6 months survival was significantly higher in the COVID-19 than in the non-COVID-19 viral pneumonia cohort (84.9% vs. 66.0%, p = 0.040). Patients with COVID-19 had an increased Murray score (3.50 vs. 3.25, p = 0.005), a decreased burden of organ dysfunction (sequential organ failure score score [8.76 vs. 10.42, p = 0.004]), an increased incidence of pulmonary embolism (69.8% vs. 24.5%, p < 0.001) and in those who survived to decannulation longer ECMO runs (19 vs. 11 days, p = 0.001). Our results suggest that survival in patients supported with EMCO for COVID-19 are at least as good as those treated for non-COVID-19 viral ARDS.

Aortic root replacement to treat type A aortic dissection: A comparison of midterm outcomes between composite valve grafts and porcine aortic roots.

BACKGROUND: Porcine aortic roots (PAR) have been reported in the literature with acceptable short- and long-term outcomes for the treatment of aortic root aneurysms. However, their efficacy in type A aortic dissection (TAAD) is yet to be defined. METHODS: Using data from a locally collated aortic dissection registry, we compared the outcomes in patients undergoing aortic root replacement for TAAD using either of two surgical options: (a) PAR or (b) composite valve grafts (CVG). A retrospective analysis was conducted for all procedures in the period from 2005 to 2018. RESULTS: A total of 252 patients underwent procedures for TAAD in the time period. Sixty-five patients had aortic root replacements (PAR n = 30, CVG n = 35). Between-group comparisons identified a younger CVG group (50.5 vs 64.5, P < .05) although all other covariates were comparable. Operative parameters were comparable between the two groups. The use of PAR did not significantly impact operative mortality (odds ratio [OR], 0.93; 95% confidence interval [CI], 0.22-3.61; P = .992), stroke (OR, 2.91, 0.25-34.09, P = .395), reoperation (OR, 0.91; 95% CI, 0.22-3.62; P = .882) or length of stay (coeff 2.33, -8.23 to 12.90; P = .659) compared to CVG. Five-year survival was similar between both groups (PAR 59% vs CVG 69%; P = .153) and reoperation was negligible. Echocardiography revealed significantly lower aortic valve gradients in the PAR group (8.69 vs 15.45mm Hg; P < .0001), and smaller left ventricular dimensions both at 6-week and 1-year follow-up (P < .05). CONCLUSIONS: This study highlights the comparable short- and midterm outcomes of PAR in cases of TAAD, in comparison to established therapy.

Establishing the Safety of Training in Off-Pump Coronary Artery Bypass Surgery: A Retrospective Comparison of Outcomes between Trainees and a Consultant Surgeon.

BACKGROUND: The safety of training in off-pump coronary artery bypass (OPCAB) surgery and the stage at which trainees should be exposed to this technique remain controversial. This single-center retrospective study aimed to compare outcomes of OPCAB surgery in consultant and trainee cases. METHODS: Between 2014 and 2018, all isolated OPCAB operations performed under the care of a consultant surgeon (G.A.) were analyzed. Cases where a surgeon below consultant grade performed at least 70% of the distal anastomoses were designated as "trainee cases" with the remaining cases designated as "consultant cases." The baseline characteristics of patients, perioperative data, and short-term outcomes were prospectively collated and analyzed. RESULTS: During the study period, 245 OPCAB cases were identified: 142 (58%) consultant and 103 (42%) trainee cases. The trainee cases were performed exclusively by trainees in the final 2 years of the UK National Cardiothoracic Training Program. Both trainee and consultant groups had low mortality with two perioperative deaths occurring in either group. The rates of serious postoperative complications including stroke (n = 1 vs. 2, p = 0.759), resternotomy for bleeding (n = 3 vs. 7, p = 0.431), and mediastinal infection (n = 2 vs. 3, p = 0.926) were low and not significantly different between the two groups. Patients operated on by trainees had a slightly longer hospital stay than those operated on by the consultant surgeon, although this did not reach statistical significance (9.9 vs. 7.9 days). CONCLUSIONS: These results demonstrate comparable outcomes in OPCAB surgery between a consultant surgeon and trainees. This study supports the conclusion that training surgeons in OPCAB is appropriate for trainees in the final years of cardiac surgery training.

The risk of misdiagnosis in acute thoracic aortic dissection: a review of current guidelines.

Acute aortic syndrome and in particular aortic dissection (AAD) persists as a cause of significant morbidity and mortality despite improvements in surgical management. This clinical review aims to explore the risks of misdiagnosis, outcomes associated with misdiagnosis and evaluate current diagnostic methods for reducing its incidence.Due to the nature of the pathology, misdiagnosing the condition and delaying management can dramatically worsen patient outcomes. Several diagnostic challenges exist, including low prevalence, rapidly propagating pathology, non-discrete symptomatology, non-specific signs, analogy with other acute conditions and lack of management infrastructure. A similarity to acute coronary syndromes is a specific concern and risks patient maltreatment. AAD with malperfusion syndromes are both a cause of misdiagnosis and marker of disease complication, requiring specifically tailored management plans from the emergency setting.Despite improvements in diagnostic measures, including imaging modalities and biomarkers, misdiagnosis of AAD remains commonplace and current guidelines are relatively limited in preventing its occurrence. This paper recommends the early use of AAD risk scoring, focused echocardiography and most importantly, fast-tracking patients to cross-sectional imaging where the suspicion of AAD is high. This has the potential to improve the diagnostic process for AAD and limit the risk of misdiagnosis. However, our understanding remains limited by the lack of large patient datasets and an adequately audited processes of emergency department practice.

Diagnosis and management of acute Type-A aortic dissection in emergency departments: Results of a UK national survey.

BACKGROUND: Type A-aortic dissection (TAAD) is a life-threatening diagnosis made in the emergency department (ED). Many presentations mimic acute coronary syndrome (ACS) and over a third of TAAD patients present with raised cardiac enzymes, many of whom have ACS-like changes on the electrocardiogram. The aim of this study was to assess the current practice in diagnosis and management of TAAD. METHODS: Between April and October 2018, a structured survey was distributed to ED Consultants across the UK. Questions surrounded: i) simulated clinical scenarios which mimicked ACS in the early stages (where TAAD could simultaneously be the diagnosis); and ii) ED infrastructure for TAAD management. RESULTS: Responses were received from 175 ED consultants across 70 hospital Trusts. In the context of chest pain and ST elevation, 97% of ED consultants considered this sufficient to diagnose ACS, and over half (54%) agreed with committing to treatment (including the use of thrombolysis) prior to further investigation. Early committers to ACS treatment were statistically less likely to ever order a CT scan or d-dimer (OR 0.31, 95% CI 0.12-0.83, p = 0.02). In total, 32% of consultants reported they would ever request a CT chest in the context of chest pain and elevated troponin. The lack of an AD algorithm was the strongest predictor of clinicians avoiding the use of more definitive investigations for TAAD (OR 0.31, 95% CI 0.01-0.64, p = 0.05). CONCLUSIONS: In TAAD patients presenting with chest pain and elevated cardiac enzymes there is a high probability of ACS treatment being commenced and a significant risk of failing to request the necessary imaging to diagnose TAAD.

What is the safety and efficacy of the use of automated fastener in heart valve surgery?

INTRODUCTION: Cor-Knot automated fastener has been used as an adjunct in heart valve surgery to eliminate the need for manual tying during valve implantation. Although reduced operative time and facilitation for minimally invasive surgery are clear benefits, whether their use translates to improved patient outcome remains debatable. This study aims to review the safety and efficacy of automated fasteners in heart valve surgeries. METHOD: Specific searches were conducted via online medical databases (Pubmed, Embase, Ovid) between 1950 and June 2019. Longitudinal studies were included that provided operative parameters. RESULTS: The initial literature search identified 3773 articles, but only eight met the inclusion criteria and were used for analysis: four studies related to aortic valve replacement (AVR), four related to mitral valve (MV) intervention (total n = 810). The meta-analysis revealed the significantly shorter aortic cross-clamp time in the Cor-knot group compared to manual tying, both in AVR and MV surgeries (P < .05). Cardiopulmonary bypass time was significantly shorter in the Cor-knot group when analyzing studies in MV surgery (weighted mean difference [WMD]: 110.0; 95% confidence interval: 12.3-207.7; P = .027) The use of Cor-Knot did not increase the risk of permanent pacemaker implantation, paravalvular leak, and 30-day mortality. The majority of studies reported no change in the length of intensive unit care and total hospital stay. CONCLUSION: We confirmed that the majority of existing literatures indicated the safety and intraoperative efficacy with automated fastener application. Nevertheless, there is currently no evidence to support automated fastened sutures can translate its intraoperative advantages to improved patient outcome.

COMPare: a prospective cohort study correcting and monitoring 58 misreported trials in real time.

BACKGROUND: Discrepancies between pre-specified and reported outcomes are an important source of bias in trials. Despite legislation, guidelines and public commitments on correct reporting from journals, outcome misreporting continues to be prevalent. We aimed to document the extent of misreporting, establish whether it was possible to publish correction letters on all misreported trials as they were published, and monitor responses from editors and trialists to understand why outcome misreporting persists despite public commitments to address it. METHODS: We identified five high-impact journals endorsing Consolidated Standards of Reporting Trials (CONSORT) (New England Journal of Medicine, The Lancet, Journal of the American Medical Association, British Medical Journal, and Annals of Internal Medicine) and assessed all trials over a six-week period to identify every correctly and incorrectly reported outcome, comparing published reports against published protocols or registry entries, using CONSORT as the gold standard. A correction letter describing all discrepancies was submitted to the journal for all misreported trials, and detailed coding sheets were shared publicly. The proportion of letters published and delay to publication were assessed over 12 months of follow-up. Correspondence received from journals and authors was documented and themes were extracted. RESULTS: Sixty-seven trials were assessed in total. Outcome reporting was poor overall and there was wide variation between journals on pre-specified primary outcomes (mean 76% correctly reported, journal range 25-96%), secondary outcomes (mean 55%, range 31-72%), and number of undeclared additional outcomes per trial (mean 5.4, range 2.9-8.3). Fifty-eight trials had discrepancies requiring a correction letter (87%, journal range 67-100%). Twenty-three letters were published (40%) with extensive variation between journals (range 0-100%). Where letters were published, there were delays (median 99 days, range 0-257 days). Twenty-nine studies had a pre-trial protocol publicly available (43%, range 0-86%). Qualitative analysis demonstrated extensive misunderstandings among journal editors about correct outcome reporting and CONSORT. Some journals did not engage positively when provided correspondence that identified misreporting; we identified possible breaches of ethics and publishing guidelines. CONCLUSIONS: All five journals were listed as endorsing CONSORT, but all exhibited extensive breaches of this guidance, and most rejected correction letters documenting shortcomings. Readers are likely to be misled by this discrepancy. We discuss the advantages of prospective methodology research sharing all data openly and pro-actively in real time as feedback on critiqued studies. This is the first empirical study of major academic journals' willingness to publish a cohort of comparable and objective correction letters on misreported high-impact studies. Suggested improvements include changes to correspondence processes at journals, alternatives for indexed post-publication peer review, changes to CONSORT's mechanisms for enforcement, and novel strategies for research on methods and reporting.

COMPare: Qualitative analysis of researchers' responses to critical correspondence on a cohort of 58 misreported trials.

BACKGROUND: Discrepancies between pre-specified and reported outcomes are an important and prevalent source of bias in clinical trials. COMPare (Centre for Evidence-Based Medicine Outcome Monitoring Project) monitored all trials in five leading journals for correct outcome reporting, submitted correction letters on all misreported trials in real time, and then monitored responses from editors and trialists. From the trialists' responses, we aimed to answer two related questions. First, what can trialists' responses to corrections on their own misreported trials tell us about trialists' knowledge of correct outcome reporting? Second, what can a cohort of responses to a standardised correction letter tell us about how researchers respond to systematic critical post-publication peer review? METHODS: All correspondence from trialists, published by journals in response to a correction letter from COMPare, was filed and indexed. We analysed the letters qualitatively and identified key themes in researchers' errors about correct outcome reporting, and approaches taken by researchers when their work was criticised. RESULTS: Trialists frequently expressed views that contradicted the CONSORT (Consolidated Standards of Reporting Trials) guidelines or made inaccurate statements about correct outcome reporting. Common themes were: stating that pre-specification after trial commencement is acceptable; incorrect statements about registries; incorrect statements around the handling of multiple time points; and failure to recognise the need to report changes to pre-specified outcomes in the trial report. We identified additional themes in the approaches taken by researchers when responding to critical correspondence, including the following: ad hominem criticism; arguing that trialists should be trusted, rather than follow guidelines for trial reporting; appealing to the existence of a novel category of outcomes whose results need not necessarily be reported; incorrect statements by researchers about their own paper; and statements undermining transparency infrastructure, such as trial registers. CONCLUSIONS: Researchers commonly make incorrect statements about correct trial reporting. There are recurring themes in researchers' responses when their work is criticised, some of which fall short of the scientific ideal. Research on methodological shortcomings is now common, typically in the form of retrospective cohort studies describing the overall prevalence of a problem. We argue that prospective cohort studies which additionally issue correction letters in real time on each individual flawed study-and then follow-up responses from trialists and journals-are more impactful, more informative for those consuming the studies critiqued, more informative on the causes of shortcomings in research, and a better use of research resources.