Risk Prediction Models for Long-Term Survival after Cardiac Surgery: A Systematic Review.

BACKGROUND: The reporting of alternative postoperative measures of quality after cardiac surgery is becoming increasingly important as in-hospital mortality rates continue to decline. This study aims to systematically review and assess risk models designed to predict long-term outcomes after cardiac surgery. METHODS: The MEDLINE and Embase databases were searched for articles published between 1990 and 2020. Studies developing or validating risk prediction models for long-term outcomes after cardiac surgery were included. Data were extracted using checklists for critical appraisal and systematic review of prediction modeling studies. RESULTS: Eleven studies were identified for inclusion in the review, of which nine studies described the development of long-term risk prediction models after cardiac surgery and two were external validation studies. A total of 70 predictors were included across the nine models. The most frequently used predictors were age (n = 9), peripheral vascular disease (n = 8), renal disease (n = 8), and pulmonary disease (n = 8). Despite all models demonstrating acceptable performance on internal validation, only two models underwent external validation, both of which performed poorly. CONCLUSION: Nine risk prediction models predicting long-term mortality after cardiac surgery have been identified in this review. Statistical issues with model development, limited inclusion of outcomes beyond 5 years of follow-up, and a lack of external validation studies means that none of the models identified can be recommended for use in contemporary cardiac surgery. Further work is needed either to successfully externally validate existing models or to develop new models. Newly developed models should aim to use standardized long-term specific reproducible outcome measures.

A systematic review of cardiac surgery clinical prediction models that include intra-operative variables.

BACKGROUND: Most cardiac surgery clinical prediction models (CPMs) are developed using pre-operative variables to predict post-operative outcomes. Some CPMs are developed with intra-operative variables, but none are widely used. The objective of this systematic review was to identify CPMs with intra-operative variables that predict short-term outcomes following adult cardiac surgery. METHODS: Ovid MEDLINE and EMBASE databases were searched from inception to December 2022, for studies developing a CPM with at least one intra-operative variable. Data were extracted using a critical appraisal framework and bias assessment tool. Model performance was analysed using discrimination and calibration measures. RESULTS: A total of 24 models were identified. Frequent predicted outcomes were acute kidney injury (9/24 studies) and peri-operative mortality (6/24 studies). Frequent pre-operative variables were age (18/24 studies) and creatinine/eGFR (18/24 studies). Common intra-operative variables were cardiopulmonary bypass time (16/24 studies) and transfusion (13/24 studies). Model discrimination was acceptable for all internally validated models (AUC 0.69-0.91). Calibration was poor (15/24 studies) or unreported (8/24 studies). Most CPMs were at a high or indeterminate risk of bias (23/24 models). The added value of intra-operative variables was assessed in six studies with statistically significantly improved discrimination demonstrated in two. CONCLUSION: Weak reporting and methodological limitations may restrict wider applicability and adoption of existing CPMs that include intra-operative variables. There is some evidence that CPM discrimination is improved with the addition of intra-operative variables. Further work is required to understand the role of intra-operative CPMs in the management of cardiac surgery patients.

Adequacy of Mediastinal Lymph Node Sampling in Patients With Lung Cancer Undergoing Lung Resection.

BACKGROUND: Intraoperative mediastinal lymph node sampling (MLNS) is a crucial component of lung cancer surgery. Whilst several sampling strategies have been clearly defined in guidelines from international organizations, reports of adherence to these guidelines are lacking. We aimed to assess our center's adherence to guidelines and determine whether adequacy of sampling is associated with survival. MATERIALS AND METHODS: A single-center retrospective review of consecutive patients undergoing lung resection for primary lung cancer between January 2013 and December 2018 was undertaken. Sampling adequacy was assessed against standards outlined in the International Association for the Study of Lung Cancer 2009 guidelines. Multivariable logistic and Cox proportional hazards regression analyses were used to assess the impact of specific variables on adequacy and of specific variables on overall survival, respectively. RESULTS: A total of 2380 patients were included in the study. Overall adequacy was 72.1% (n= 1717). Adherence improved from 44.8% in 2013 to 85.0% in 2018 (P< 0.001). Undergoing a right-sided resection increased the odds of adequate MLNS on multivariable logistic regression (odds ratio 1.666, 95% confidence interval [CI]: 1.385-2.003, P< 0.001). Inadequate MLNS was not significantly associated with reduced overall survival on log rank analysis (P= 0.340) or after adjustment with multivariable Cox proportional hazards (hazard ratio 0.839, 95% CI 0.643-1.093). CONCLUSIONS: Adherence to standards improved significantly over time and was significantly higher for right-sided resections. We found no evidence of an association between adequate MLNS and overall survival in this cohort. A pressing need remains for the introduction of national guidelines defining acceptable performance.

The Impact of Initial Postoperative Destination on Unplanned Critical Care Admissions After Lung Resection.

OBJECTIVES: Despite an increasing proportion of patients undergoing lung resection being managed postoperatively in a ward-based environment, studies analyzing the impact of initial postoperative destination (IPD) on perioperative outcomes and unplanned critical care admission (UCCA) are lacking. DESIGN: A single-center retrospective review. SETTING: A cardiothoracic surgery center in the Northwest of England. PARTICIPANTS: A total of 3,841 patients between 2012 and 2018. INTERVENTIONS: All patients underwent lung resection. Patients were classified as either IPD ward or IPD critical care. MEASUREMENTS AND MAIN RESULTS: Outcomes assessed included in-hospital and 90-day mortality and UCCA. Differences in mortality rates between groups were assessed using the chi-square test. Multivariate logistic regression analyses were performed to identify variables independently associated with 90-day mortality and UCCA. In total, 23.8% (n = 913) of patients went to critical care as their IPD. Overall in-hospital mortality was 1.6% (n = 62), and 90-day mortality was 2.9% (n = 112). The rate of UCCA was 10.5% (n = 404) and was significantly higher for IPD ward patients compared to IPD critical care patients (11.9% v 6.2%, p < 0.001). The 90-day mortality rates after UCCA were 5.2% (IPD ward) and 19.3% (IPD critical care) (p < 0.001). Advanced age, worse pulmonary function, IPD ward, and timing of surgery were all independently associated with UCCA. CONCLUSIONS: Most patients undergoing lung resection can be managed safely postoperatively in a ward-based environment. Short-term mortality is higher after UCCA, with patients who experience readmission to critical care at the highest risk of death. Patients should receive additional monitoring immediately following discharge from critical care.

Preoperative Anemia is Associated With Worse Long-Term Survival After Lung Cancer Resection: A Multicenter Cohort Study of 5,029 Patients.

OBJECTIVES: Although some evidence to suggest an association between preoperative anemia and reduced overall survival exists, contemporary studies investigating the impact of preoperative anemia on outcomes after resection for primary lung cancer are lacking. DESIGN: A multicenter retrospective review. SETTING: Two tertiary cardiothoracic surgery centers in the Northwest of England. PARTICIPANTS: A total of 5,029 patients between 2012 and 2018. INTERVENTIONS: All patients underwent lung resection for primary lung cancer. Patients were classified as anemic based on the World Health Organization definition. Men with hemoglobin <130 g/L and women with hemoglobin <120 g/L were considered to be anemic. MEASUREMENTS AND MAIN RESULTS: Outcomes assessed included perioperative mortality, 90-day mortality, and overall survival. Multivariate logistic and Cox regression analyses were used to assess the impact of preoperative anemia on 90-day mortality and overall survival, respectively. Overall, preoperatively, 24.0% (n = 1207) of patients were anemic. The 90-day mortality for anemic and nonanemic patients was 5.6% and 3.1%, respectively (p < 0.001). After multivariate adjustment, preoperative anemia was not associated with increased 90-day mortality. However, a log-rank analysis demonstrated reduced overall survival for anemic patients (p < 0.001). After multivariate adjustment, preoperative anemia was found to be independently associated with reduced overall survival (hazard ratio 1.287, 95% confidence interval 1.141-1.451, p < 0.001). CONCLUSIONS: Although anemia was not an independent predictor of short-term outcomes, it was independently associated with significantly reduced survival for patients undergoing resection for lung cancer. Further work is required to understand why anemia reduces long-term survival and whether pathways for anemic patients can be adapted to improve long-term outcomes.

Predicting Readmission to Intensive Care After Cardiac Surgery Within Index Hospitalization: A Systematic Review.

Readmission to the cardiac intensive care unit after cardiac surgery has significant implications for both patients and healthcare providers. Identifying patients at risk of readmission potentially could improve outcomes. The objective of this systematic review was to identify risk factors and clinical prediction models for readmission within a single hospitalization to intensive care after cardiac surgery. PubMed, MEDLINE, and EMBASE databases were searched to identify candidate articles. Only studies that used multivariate analyses to identify independent predictors were included. There were 25 studies and five risk prediction models identified. The overall rate of readmission pooled across the included studies was 4.9%. In all 25 studies, in-hospital mortality and duration of hospital stay were higher in patients who experienced readmission. Recurring predictors for readmission were preoperative renal failure, age >70, diabetes, chronic obstructive pulmonary disease, preoperative left ventricular ejection fraction <30%, type and urgency of surgery, prolonged cardiopulmonary bypass time, prolonged postoperative ventilation, postoperative anemia, and neurologic dysfunction. The majority of readmissions occurred due to respiratory and cardiac complications. Four models were identified for predicting readmission, with one external validation study. As all models developed to date had limitations, further work on larger datasets is required to develop clinically useful models to identify patients at risk of readmission to the cardiac intensive care unit after cardiac surgery.

A Novel Patient-Specific Model for Predicting Severe Oliguria; Development and Comparison With Kidney Disease: Improving Global Outcomes Acute Kidney Injury Classification.

OBJECTIVES: The Kidney Disease: Improving Global Outcomes urine output criteria for acute kidney injury lack specificity for identifying patients at risk of adverse renal outcomes. The objective was to develop a model that analyses hourly urine output values in real time to identify those at risk of developing severe oliguria. DESIGN: This was a retrospective cohort study utilizing prospectively collected data. SETTING: A cardiac ICU in the United Kingdom. PATIENTS: Patients undergoing cardiac surgery between January 2013 and November 2017. INTERVENTIONS: None. MEASUREMENT AND MAIN RESULTS: Patients were randomly assigned to development (n = 981) and validation (n = 2,389) datasets. A patient-specific, dynamic Bayesian model was developed to predict future urine output on an hourly basis. Model discrimination and calibration for predicting severe oliguria (< 0.3 mL/kg/hr for 6 hr) occurring within the next 12 hours were tested in the validation dataset at multiple time points. Patients with a high risk of severe oliguria (p > 0.8) were identified and their outcomes were compared with those for low-risk patients and for patients who met the Kidney Disease: Improving Global Outcomes urine output criterion for acute kidney injury. Model discrimination was excellent at all time points (area under the curve > 0.9 for all). Calibration of the model's predictions was also excellent. After adjustment using multivariable logistic regression, patients in the high-risk group were more likely to require renal replacement therapy (odds ratio, 10.4; 95% CI, 5.9-18.1), suffer prolonged hospital stay (odds ratio, 4.4; 95% CI, 3.0-6.4), and die in hospital (odds ratio, 6.4; 95% CI, 2.8-14.0) (p < 0.001 for all). Outcomes for those identified as high risk by the model were significantly worse than for patients who met the Kidney Disease: Improving Global Outcomes urine output criterion. CONCLUSIONS: This novel, patient-specific model identifies patients at increased risk of severe oliguria. Classification according to model predictions outperformed the Kidney Disease: Improving Global Outcomes urine output criterion. As the new model identifies patients at risk before severe oliguria develops it could potentially facilitate intervention to improve patient outcomes.

Are Serum Potassium and Magnesium Levels Associated with Atrial Fibrillation After Cardiac Surgery?

OBJECTIVES: Potassium and magnesium are frequently administered after cardiac surgery to reduce the risk of atrial fibrillation (AF). The evidence for this practice is unclear. This study was designed to evaluate the relationship between serum potassium and magnesium levels and AF after cardiac surgery. DESIGN: Observational cohort study. SETTING: A cardiac intensive care unit in the United Kingdom. PARTICIPANTS: Patients undergoing cardiac surgery between January 2013 and November 2017. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: Cardiac rhythm was assessed using continuous electrocardiogram (ECG) monitoring in 3,068 patients on the cardiac intensive care unit. Associations between serum potassium and magnesium concentrations extracted from hospital databases and postoperative AF were assessed using univariable and multivariable analyses. The association between electrolyte supplementation therapy and AF was also analyzed. AF developed within 72 hours of cardiac surgery in 545 (17.8%) of the 3,068 patients. After adjusting for logistic EuroSCORE, surgery type, cardiopulmonary bypass time and age, mean serum potassium concentration <4.5 mmol/L was associated with an increased risk of AF (odds ratio [OR] 1.43 (95% confidence interval (CI): 1.17-1.75), p < 0.001). Mean magnesium concentration <1.0 mmol/L was not associated with an increased risk of AF (OR 0.89, 0.71-1.13, p = 0.342), but the administration of magnesium was associated with increased risk of developing AF (OR 1.61, 1.33-1.96, p < 0.001). CONCLUSIONS: Maintaining a serum potassium concentration ≥4.5 mmol/L after cardiac surgery may reduce the incidence of postoperative AF. Magnesium supplementation was associated with an increased risk of postoperative AF. Prospective randomized trials are required to clarify these associations.

The KDIGO acute kidney injury guidelines for cardiac surgery patients in critical care: a validation study.

BACKGROUND: The Kidney Disease: Improving Global Outcomes (KDIGO) Acute Kidney Injury (AKI) guidelines assign the same stage of AKI to patients whether they fulfil urine output criteria, serum creatinine criteria or both criteria for that stage. This study explores the validity of the KDIGO guidelines as a tool to stratify the risk of adverse outcomes in cardiac surgery patients. METHODS: Prospective data from consecutive adult patients admitted to the cardiac intensive care unit (CICU) following cardiac surgery between January 2013 and May 2015 were analysed. Patients were assigned to groups based on the criteria they met for each stage of AKI according to the KDIGO guidelines. Short and mid-term outcomes were compared between these groups. RESULTS: A total of 2267 patients were included with 772 meeting criteria for AKI-1 and 222 meeting criteria for AKI-2. After multivariable adjustment, patients meeting both urine output and creatinine criteria for AKI-1 were more likely to experience prolonged CICU stay (OR 4.9, 95%CI 3.3-7.4, p < 0.01) and more likely to require renal replacement therapy (OR 10.5, 95%CI 5.5-21.9, p < 0.01) than those meeting only the AKI-1 urine output criterion. Patients meeting both urine output and creatinine criteria for AKI-1 were at an increased risk of mid-term mortality compared to those diagnosed with AKI-1 by urine output alone (HR 2.8, 95%CI 1.6-4.8, p < 0.01). Patients meeting both urine output and creatinine criteria for AKI-2 were more likely to experience prolonged CICU stay (OR 16.0, 95%CI 3.2-292.0, p < 0.01) or require RRT (OR 11.0, 95%CI 4.2-30.9, p < 0.01) than those meeting only the urine output criterion. Patients meeting both urine output and creatinine criteria for AKI-2 were at a significantly increased risk of mid-term mortality compared to those diagnosed with AKI-2 by urine output alone (HR 3.6, 95%CI 1.4-9.3, p < 0.01). CONCLUSIONS: Patients diagnosed with the same stage of AKI by different KDIGO criteria following cardiac surgery have significantly different short and mid-term outcomes. The KDIGO criteria need to be revisited before they can be used to stratify reliably the severity of AKI in cardiac surgery patients. The utility of the criteria also needs to be explored in other settings.

Composite end points and competing risks analysis.

Composite end points are common primary outcomes in clinical trials. Their main benefit of utilizing a composite outcome is increasing the number of primary outcome events, meaning fewer participants are required to deliver an adequately powered trial. By combining multiple important end points in the primary outcome rather than having to select only 1, composite end points potentially make clinically meaningful benefits easier to detect and avoid ranking outcomes hierarchically. However, there are a number of important considerations when designing and interpreting clinical trials that utilize composite end points. In this Statistical Primer, issues with composite end points such as competing events, halo effect, risk of bias, time-to-event limitations and the win ratio are discussed in the context of real world clinical trials.

Pre-Operative Measures of Systemic Inflammation Predict Survival After Surgery for Primary Lung Cancer.

BACKGROUND: Measures of systemic inflammation (MSIs) have been developed and shown to help predict prognosis in patients with lung cancer. However, studies investigating the impact of MSIs on outcomes solely in cohorts of patients undergoing curative-intent resection of NSCLC are lacking. In the era of individualized therapies, targeting inflammatory pathways could represent a novel addition to the armamentarium of lung cancer treatment. METHODS: A multicentre retrospective review of patients who underwent primary lung cancer resection between 2012 and 2018 was undertaken. MSIs assessed were neutrophil to lymphocyte ratio (NLR), platelet to lymphocyte ratio (PLR), systemic immune inflammation index (SII), advanced lung cancer inflammation index (ALI), prognostic nutritional index (PNI) and haemoglobin albumin lymphocyte platelet (HALP) score. Cox regression analysis was performed to assess the impact of MSIs on overall survival. RESULTS: A total of 5029 patients were included in the study. Overall 90-day mortality was 3.7% (n = 185). All MSIs were significantly associated with overall survival on univariable analysis. After multivariable Cox regression analyses, lower ALI (expressed as a continuous variable) (HR 1.000, 95% CI 1.000-1.000, P = .049) and ALI <366.43 (expressed as a dichotomous variable) (HR 1.362, 95% CI 1.137-1.631, P < .001) remained independently associated with reduced overall survival. CONCLUSIONS: MSIs have emerged in this study as potentially important factors associated with survival following lung resection for NSCLC with curative intent. In particular, ALI has emerged as independently associated with long-term outcomes. The role of MSIs in the clinical management of patients with primary lung cancer requires further investigation.

Wedge resection versus lobectomy in T1 lung cancer patients: a propensity matched analysis.

OBJECTIVES: Performing wedge resection rather than lobectomy for primary lung cancer remains controversial. Recent studies demonstrate no survival advantage for non-anatomical resection compared to lobectomy in patients with early-stage lung cancer. The objective of this study was to investigate whether in patients with T1 tumours, non-anatomical wedge resection is associated with equivalent survival to lobectomy. METHODS: This was a retrospective cohort study of patients who underwent lung resection at the Lancashire Cardiac Centre between April 2005 and April 2018. Patients were subjected to multidisciplinary team discussion. The extent of resection was decided by the team based on British Thoracic Society guidelines. The primary outcome was overall survival. Propensity matching of patients with T1 tumours was also performed to determine whether differences in survival rates exist in a subset of these patients with balanced pre-operative characteristics. RESULTS: There were 187 patients who underwent non-anatomical wedge resection and 431 patients who underwent lobectomy. Cox modelling demonstrated no survival difference between groups for the first 1.6 years then a risk of death 3-fold higher for wedge resection group after 1.6 years (HR 3.14, CI 1.98-4.79). Propensity matching yielded 152 pairs for which 5-year survival was 66.2% for the lobectomy group and 38.5% for the non-anatomical wedge group (SMD = 0.58, p = 0.003). CONCLUSIONS: Non-anatomical wedge resection was associated with significantly reduced 5-year survival compared to lobectomy in matched patients. Lobectomy should remain the standard of care for patients with early-stage lung cancer who are fit enough to undergo surgical resection.

Healthcare utilisation in patients with long-term conditions during the COVID-19 pandemic: a population-based observational study of all patients across Greater Manchester, UK.

OBJECTIVES: Data on population healthcare utilisation (HCU) across both primary and secondary care during the COVID-19 pandemic are lacking. We describe primary and secondary HCU stratified by long-term conditions (LTCs) and deprivation, during the first 19 months of COVID-19 pandemic across a large urban area in the UK. DESIGN: A retrospective, observational study. SETTING: All primary and secondary care organisations that contributed to the Greater Manchester Care Record throughout 30 December 2019 to 1 August 2021. PARTICIPANTS: 3 225 169 patients who were registered with or attended a National Health Service primary or secondary care service during the study period. PRIMARY OUTCOMES: Primary care HCU (incident prescribing and recording of healthcare information) and secondary care HCU (planned and unplanned admissions) were assessed. RESULTS: The first national lockdown was associated with reductions in all primary HCU measures, ranging from 24.7% (24.0% to 25.5%) for incident prescribing to 84.9% (84.2% to 85.5%) for cholesterol monitoring. Secondary HCU also dropped significantly for planned (47.4% (42.9% to 51.5%)) and unplanned admissions (35.3% (28.3% to 41.6%)). Only secondary care had significant reductions in HCU during the second national lockdown. Primary HCU measures had not recovered to prepandemic levels by the end of the study. The secondary admission rate ratio between multi-morbid patients and those without LTCs increased during the first lockdown by a factor of 2.40 (2.05 to 2.82; p<0.001) for planned admissions and 1.25 (1.07 to 1.47; p=0.006) for unplanned admissions. No significant changes in this ratio were observed in primary HCU. CONCLUSION: Major changes in primary and secondary HCU were observed during the COVID-19 pandemic. Secondary HCU reduced more in those without LTCs and the ratio of utilisation between patients from the most and least deprived areas increased for the majority of HCU measures. Overall primary and secondary care HCU for some LTC groups had not returned to prepandemic levels by the end of the study.

Safety of curative-intent lung cancer surgery in older patients (octogenarians): A contemporary multicentre cohort study.

INTRODUCTION: Despite octogenarians representing an ever-increasing proportion of patients with lung cancer, there is a paucity of evidence describing outcomes after lung resection for these patients. We aimed to evaluate short and mid-term outcomes for octogenarians after lung resection. MATERIALS AND METHODS: A total of 5,470 consecutive patients undergoing lung resection for primary lung cancer from 2012-2019 in two UK centres were included. Primary outcomes were perioperative, 90-day, and one-year mortality in the octogenarian vs. non-octogenarian cohort. Appropriate statistical tests were used to compare outcomes between octogenarian and non-octogenarian patients. Secondary outcomes were post-operative complications and to validate the performance of the Thoracoscore model in the octogenarian cohort. RESULTS: Overall, 9.4% (n=513) of patients were aged ≥80. The rates of 90-day mortality, one-year mortality, and post-operative atrial fibrillation were significantly higher for octogenarians. The one-year mortality rate for octogenarians fell significantly over time (2012-2015: 16.5% vs 2016-2019: 10.2%, p=0.034). Subgroup analysis (2016-2019 only) demonstrated no significant difference in peri-operative, 90-day, or one-year mortality between octogenarian and non-octogenarian patients. Validation of the Thoracoscore model demonstrated modest discrimination and acceptable calibration. DISCUSSION: Mortality for octogenarians fell significantly over time in this study. Indeed, when confined to the most recent time period, comparable rates of both 90-day and one-year mortality for octogenarian and non-octogenarian patients were seen. Whilst preventative strategies to reduce the incidence of post-operative atrial fibrillation in octogenarians should be considered, these findings demonstrate that following appropriate patient selection, octogenarians can safely undergo lung resection for lung cancer.

The Relationship Between Cardiac Troponin in People Hospitalised for Exacerbation of COPD and Major Adverse Cardiac Events (MACE) and COPD Readmissions.

Background: No single biomarker currently risk stratifies chronic obstructive pulmonary disease (COPD) patients at the time of an exacerbation, though previous studies have suggested that patients with elevated troponin at exacerbation have worse outcomes. This study evaluated the relationship between peak cardiac troponin and subsequent major adverse cardiac events (MACE) including all-cause mortality and COPD hospital readmission, among patients admitted with COPD exacerbation. Methods: Data from five cross-regional hospitals in England were analysed using the National Institute of Health Research Health Informatics Collaborative (NIHR-HIC) acute coronary syndrome database (2008-2017). People hospitalised with a COPD exacerbation were included, and peak troponin levels were standardised relative to the 99th percentile (upper limit of normal). We used Cox Proportional Hazard models adjusting for age, sex, laboratory results and clinical risk factors, and implemented logarithmic transformation (base-10 logarithm). The primary outcome was risk of MACE within 90 days from peak troponin measurement. Secondary outcome was risk of COPD readmission within 90 days from peak troponin measurement. Results: There were 2487 patients included. Of these, 377 (15.2%) patients had a MACE event and 203 (8.2%) were readmitted within 90 days from peak troponin measurement. A total of 1107 (44.5%) patients had an elevated troponin level. Of 1107 patients with elevated troponin at exacerbation, 256 (22.8%) had a MACE event and 101 (9.0%) a COPD readmission within 90 days from peak troponin measurement. Patients with troponin above the upper limit of normal had a higher risk of MACE (adjusted HR 2.20, 95% CI 1.75-2.77) and COPD hospital readmission (adjusted HR 1.37, 95% CI 1.02-1.83) when compared with patients without elevated troponin. Conclusion: An elevated troponin level at the time of COPD exacerbation may be a useful tool for predicting MACE in COPD patients. The relationship between degree of troponin elevation and risk of future events is complex and requires further investigation.

Coronary artery bypass surgery in the UK, trends in activity and outcomes from a 15-year complete national series.

OBJECTIVES: The aim of this study was to review the UK national trends in activity and outcome in coronary artery bypass graft (CABG) over a 15-year period (2002-2016). METHODS: Validated data collected (2002-2016) and uploaded to National Institute for Cardiovascular Outcomes Research were used to generate summary data from the National Adult Cardiac Surgery Audit Database for the analysis. Logistic European System of Cardiac Operative Risk Evaluation was used for risk stratification with recalibration applied for governance. Data were analysed by financial year and presented as numerical, categorical, %, mean and standard deviation where appropriate. Mortality was recorded as death in hospital at any time after index CABG operation. RESULTS: A total of 347 626 CABG procedures (282 883 isolated CABG, 61 109 CABG and valve and 4132 redo CABG) were recorded. Over this period annual activity reduced from 66.6% of workload to 41.7%. The mean age for isolated CABG was 65.7 years. The mean log European System of Cardiac Operative Risk Evaluation was 3.1, 5.9 and 23.2 for elective, urgent and emergency isolated CABG, respectively. There was a decline in the observed mortality for all procedures. Overall mortality for isolated CABG surgery is now 1.0% and only 0.6% for elective operations. CONCLUSIONS: Quality of care and risk-adjusted mortality rates have consistently improved over the last 15 years despite the increasing risk profile of patients. There have been a consistent decline in overall case volumes and a three-fold increase in elderly cases.

Cardiac surgery in older patients: hospital outcomes during a 15-year period from a complete national series.

OBJECTIVES: The objective was to review national trends in activity and hospital outcomes in older patients having cardiac surgery over a 15-year time period. METHODS: Data were collected prospectively and uploaded to the National Institute for Cardiovascular Outcomes Research electronically. Data were validated, cleaned and processed using reproducible algorithms. Mortality was death in hospital after index operation. RESULTS: A total of 227 442 cardiac procedures were recorded in patients aged ≥70 years of which 46 354 were in those aged ≥80 years. Overall patients aged ≥70 years represented 43% of all adult cardiac surgery in the most recent study year. The annual proportion of surgery in patients ≥80 years increased from 4.1% to 10.8% between the first and last study years. There has been a significant linear increase in octogenarian valve [ß 67.44, 95% confidence interval (CI) 55.04 to 79.83, P < 0.001] and coronary artery bypass graft surgery (ß 32.53, 95% CI 6.16 to 58.90, P = 0.020) patients. In-hospital mortality reduced significantly for patients aged 70-79 years (ß -0.17, 95% CI -0.20 to -0.13, P < 0.001) and all patients aged ≥80 (ß -0.37, 95% CI -0.45 to -0.30, P < 0.001). The median length of hospital stay was 7 days for 70-79 and 9 days for ≥80 group, compared with 7 days for the whole cohort <70 years. CONCLUSIONS: This study represents the largest complete validated national dataset of cardiac surgery in the entire population of older patients. Octogenarians represent 11% of adult patients having cardiac surgery by the end of the study period, a three-fold increase from the start. In-hospital mortality in patients aged ≥80 years halved during study period to only 4% despite high logistic EuroSCORE of 15%. Cardiac surgery in octogenarians places a higher demand on resources, however, with an increased postoperative length of stay.