Acute Risk Change: An Innovative Measure of Operative Adverse Events and Perioperative Team Performance.

OBJECTIVES: Cardiac surgical risk models predict mortality preoperatively, whereas intensive care unit (ICU) models predict mortality postoperatively. Finding a large difference between the 2 (an acute risk change [ARC]) may reflect an alteration in the status of the patient related to the surgery. An adverse ARC was associated with morbidity and mortality in an Australian population. The aims of this study were to validate ARC in a UK population and to investigate the possible mechanisms behind ARC. DESIGN: This was a retrospective case-control study. SETTING: Single, high-volume cardiothoracic hospital. PARTICIPANTS: Data from 4,842 cardiac surgical patients were collected between 2013 and 2015. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: EuroSCORE was recalibrated to each preceding year's data. ARC was defined as postoperative minus preoperative percentage mortality risk. Association among ARC, morbidity, and mortality was tested. Cases with large adverse ARC (greater than +15%) were compared with cases with large favorable ARC (less than -10%) with regard to intraoperative adverse events, unmeasured patient risk factors, and postoperative events. Adverse ARC was associated with hospital mortality, ICU stay, ICU readmission, renal support, prolonged intubation and return to the operating room (p < 0.001). Intraoperative adverse events occurred in 23 of 33 patients with adverse ARC; however, only 2 of 17 patients with favorable ARC reported adverse events (p < 0.001). Unmeasured risk factors were present in 48% of patients in the adverse ARC group. CONCLUSION: ARC is a readily available and sensitive marker that correlates strongly with morbidity and mortality. The use of ARC in local and national quality monitoring could identify areas for improvement of the quality of cardiac surgical care.

The effect of pulsatile cardiopulmonary bypass on the need for haemofiltration in patients with renal dysfunction undergoing cardiac surgery.

OBJECTIVES: The aim of our study was to investigate the effects of pulsatile cardiopulmonary bypass (CPB) on renal function and the need for haemofiltration in patients with preoperative renal impairment undergoing cardiac surgery. METHODS: Clinical data were collected prospectively for patients undergoing cardiac surgery with pulsatile CPB (Group A, n=66) and compared to matched patients with standard non-pulsatile CPB (Group B, n=66). Patients included in the study had mild renal impairment and at least moderate risk from surgery as defined by logistic EuroSCORE. Emergency operations were excluded. RESULTS: Patients in Groups A and B had similar age (71 ± 10 versus 70 ± 10 years), sex distribution, mean preoperative renal function (creatinine clearance 63.9 ± 28 versus 67.7 ± 27.3 ml/min) and overall risk profile as predicted by the logistic EuroSCORE (8 ± 8.3 versus 11.05±13.3, p=0.122). Intraoperative variables were comparable with respect to bypass and cross-clamp times (96 ± 37 minutes and 64 ± 28 minutes versus 103 ± 40 minutes and 70 ± 33 minutes in Groups A and B, respectively). A smaller proportion of patients in Group A (4.5% versus 15%, p=0.076) required haemofiltration in the postoperative period. Postoperative mortality was low in both groups (Group A 1.54% versus Group B 3.03%, p=1.00). CONCLUSION: Within the limitations imposed by retrospective analyses, our study demonstrates that pulsatile CPB may confer a reno-protective effect in higher-risk patients with pre-existing mild renal dysfunction undergoing cardiac surgery.

Impact of the anesthesiologist and surgeon on cardiac surgical outcomes.

OBJECTIVE: To determine the impact of anesthesiologists, surgeons, and their monthly caseload volume on mortality after cardiac surgery. DESIGN: Ten-year audit of prospectively collected cardiac surgical data. SETTING: Large adult cardiothoracic hospital. PARTICIPANTS: A total of 18,569 cardiac surgical patients in the decade from April 2002 through March 2012, plus 21 consultant surgeons and 29 consultant anesthesiologists. INTERVENTIONS: Major risk-stratified cardiac surgical operations. METHODS: The primary outcome was in-hospital death. Random intercept models for the surgeon and anesthesiologist cluster, respectively, were fitted, achieving risk-adjustment through the logistic EuroSCORE. The intraclass correlation coefficient (ICC) subsequently was used to measure the amount of outcome variation due to clustering. MEASUREMENTS AND MAIN RESULTS: After exclusions (duplicates, very-short-term appointments, and cases performed by more than one consultant), there were 18,426 patients with 581 (3.15%) in-hospital deaths. The overwhelming factor associated with outcome variation was the patient risk profile, accounting for 97.14% of the variation. The impact of the surgeon was small (ICC = 2.78%), and the impact of the anesthesiologist was negligible (ICC = 0.08%). Low monthly surgeon volume of surgery, adjusted for average case mix, was associated with higher risk-adjusted mortality (odds ratio = 0.93, 95% CI 0.87-0.98). CONCLUSIONS: Outcome was determined primarily by the patient. There were small but significant differences in outcome between surgeons. The attending anesthesiologist did not affect patient outcome in this institution. Low average monthly surgeon volume was a significant risk factor. In contrast, low average monthly anesthesiologist volume had no effect.

Surgical treatment of atrial fibrillation in the heart failure population.

Surgery to correct a structural heart valve problem can restore sinus rhythm in approximately one-fifth of patients with atrial fibrillation (AF), and the addition of a maze procedure will increase this proportion. Evidence shows that the maze procedure may restore atrial function in some patients and may have beneficial effects on functional symptoms and prognosis. The role of the maze procedure as an isolated treatment for lone AF in the context of heart failure with no structurally correctable cause is unknown. Future progress will determine the appropriate indications for treatment and the risks and benefits of any intervention.

Formal consensus study on surgery to replace the aortic valve in adults aged 18-60 years.

OBJECTIVE: There is uncertainty about surgical procedures for adult patients aged 18-60 years undergoing aortic valve replacement (AVR). Options include conventional AVR (mechanical, mAVR; tissue, tAVR), the pulmonary autograft (Ross) and aortic valve neocuspidisation (Ozaki). Transcatheter treatment may be an option for selected patients. We used formal consensus methodology to make recommendations about the suitability of each procedure. METHODS: A working group, supported by a patient advisory group, developed a list of clinical scenarios across seven domains (anatomy, presentation, cardiac/non-cardiac comorbidities, concurrent treatments, lifestyle, preferences). A consensus group of 12 clinicians rated the appropriateness of each surgical procedure for each scenario on a 9-point Likert scale on two separate occasions (before and after a 1-day meeting). RESULTS: There was a consensus that each procedure was appropriate (A) or inappropriate (I) for all clinical scenarios as follows: mAVR: total 76% (57% A, 19% I); tAVR: total 68% (68% A, 0% I); Ross: total 66% (39% A, 27% I); Ozaki: total 31% (3% A, 28% I). The remainder of percentages to 100% reflects the degree of uncertainty. There was a consensus that transcatheter aortic valve implantation is appropriate for 5 of 68 (7%) of all clinical scenarios (including frailty, prohibitive surgical risk and very limited life span). CONCLUSIONS: Evidence-based expert opinion emerging from a formal consensus process indicates that besides conventional AVR options, there is a high degree of certainty about the suitability of the Ross procedure in patients aged 18-60 years. Future clinical guidelines should include the option of the Ross procedure in aortic prosthetic valve selection.

Selenoprotein deficiency disorder predisposes to aortic aneurysm formation.

Aortic aneurysms, which may dissect or rupture acutely and be lethal, can be a part of multisystem disorders that have a heritable basis. We report four patients with deficiency of selenocysteine-containing proteins due to selenocysteine Insertion Sequence Binding Protein 2 (SECISBP2) mutations who show early-onset, progressive, aneurysmal dilatation of the ascending aorta due to cystic medial necrosis. Zebrafish and male mice with global or vascular smooth muscle cell (VSMC)-targeted disruption of Secisbp2 respectively show similar aortopathy. Aortas from patients and animal models exhibit raised cellular reactive oxygen species, oxidative DNA damage and VSMC apoptosis. Antioxidant exposure or chelation of iron prevents oxidative damage in patient's cells and aortopathy in the zebrafish model. Our observations suggest a key role for oxidative stress and cell death, including via ferroptosis, in mediating aortic degeneration.

Five-year results of Amaze: a randomized controlled trial of adjunct surgery for atrial fibrillation.

OBJECTIVES: The Amaze trial showed that adding atrial fibrillation (AF) surgery to cardiac operations increased return to sinus rhythm (SR) without impact on quality of life or survival at 2 years. We report outcomes to 5 years. METHODS: In a multicentre, phase III, pragmatic, double-blind, randomized controlled superiority trial, cardiac surgery patients with >3 months of AF were randomized 1:1 to adjunct AF surgery or control. Primary outcomes of 1-year SR restoration and 2-year quality-adjusted survival were already reported. This study reports on rhythm, survival, quality-adjusted survival, stroke, medication and safety to 5 years. RESULTS: Between 2009 and 2014, 352 patients were randomized. By 5 years 79 died, 58 withdrew, 34 were lost to follow-up and the remaining 182 provided data. AF surgery significantly increased the odds of remaining in SR at 5 years {odds ratio = 2.98 [95% confidence interval (CI) 1.23, 7.17], P = 0.015}. There was a non-significant decrease in stroke incidence [odds ratio = 0.605 (95% CI 0.284, 1.287), P = 0.19], but no improved survival [5-year survival: AF surgery 77.3% (95% CI 71.1%, 83.5%), controls 77.8% (95% CI 71.7%, 84.0%), P = 0.85]. Quality-adjusted survival difference was negligible (-0.03; 95% CI -0.33, 0.27, P = 0.85). The composite of survival free of stroke and AF was better in the AF surgery group [odds ratio = 2.34 (95% CI 1.03, 5.31)]. There were no other differences. CONCLUSIONS: Adjunct AF surgery confers a higher rate of SR to 5 years and a better composite outcome of survival free of stroke and AF but has no impact on overall or quality-adjusted survival or other clinical outcomes. CLINICAL TRIAL REGISTRATION NUMBER: ISRCTN82731440.

A clinico-pathological conference on constrictive pericarditis secondary to rheumatoid arthritis: a case report with expert commentary and review of the literature.

Constrictive pericarditis is the commonest cardiac complication of rheumatoid arthritis (RA). Two percent of patients with RA develop significant clinical symptoms of pericarditis, which may not correlate with joint disease duration or severity. Symptoms are often vague and non-specific, which frequently delays the diagnosis and subsequent management. Surgical excision of the pericardium is the only definitive treatment option. We present the case of a 60 year-old lady with RA who presented with symptoms due to pericardial constriction and underwent radical pericardectomy.

Cardiac surgery in nonagenarians: single-centre series and review.

BACKGROUND: Cardiac surgery is widely believed to be an excessively high-risk intervention for very elderly patients with coronary artery or valvular disease. However, as life expectancy and the prospect of sustained quality of life into older age increase, this assumption should be challenged so that surgery is not denied to patients who may derive significant symptomatic benefit with acceptable levels of operative risk. OBJECTIVE: To evaluate outcomes from cardiac surgery in nonagenarian patients. DESIGN: Analysis of prospectively collected single-centre data and review of outcomes reported in the literature. RESULTS: Twenty-three patients (13 males) aged 90 years or more underwent open cardiac surgery between 1998 and 2007. Four patients died within 30 days of surgery (surgical mortality 17.4%) and all-cause in-hospital morbidity was 74%. Actuarial survival at 1 and 5 years was estimated at 72 and 54%, respectively. Comparison of patients' survival against age-matched life tables for the English population found a standardised mortality ratio of 0.57 (95% CI: 0.24-0.99; one-sample log-rank test chi(2) = 3.93; p < 0.05) representing a significant survival benefit associated with surgery. The majority of patients reported symptomatic improvement reflected by significant decreases in angina and dyspnoea scores. Six single-centre series of nonagenarians and 3 reviews from national databases in the US and UK were identified in the literature. Pooled surgical mortality was 12.7% (95% CI: 8.7-17.3%) with no significant heterogeneity (chi(2) = 4.12; p = 0.77; I(2) = 0). CONCLUSION: Cardiac surgery in the elderly carries higher operative risk than in younger patients. However, in selected nonagenarians, surgery can be performed with acceptable morbidity and early mortality, and patients gain significant symptomatic relief and survival benefit.

Aortic valve replacement: is there an implant size variation across Europe?

BACKGROUND AND AIMS OF THE STUDY: Prompted by anecdotal evidence and observations by surgeons, an investigation was undertaken into the potential differences in implanted aortic valve prosthesis sizes, during aortic valve replacement (AVR) procedures, between northern and southern European countries. METHODS: A multi-institutional, non-randomized, retrospective analysis was conducted among 2,932 patients who underwent AVR surgery at seven tertiary cardiac surgery centers throughout Europe. Demographic and perioperative variables including valve size and type, body surface area (BSA) and early mortality were collected. Group analysis by patient geographic distribution and by annular diameter of the prosthesis utilized was conducted. Patients with a manufacturer's labeled prosthesis size > or = 21 mm were assigned to the 'large' aortic size subset, while those with a prosthesis size < 21 mm were assigned to the 'small' aortic size subset. Effective orifice area indices were calculated for all patients to assess the geographic distribution of patient-prosthesis mismatch. Univariable and multivariable logistic regression analyses adjusting for possible confounding variables were performed. RESULTS: Prostheses with diameter < 21 mm were implanted at almost twice the rate in southern Europe compared to the north (56.4% versus 26.7%, p < 0.01). The mean valve size was also smaller in southern compared to northern European patients (21.6 +/- 2.1 mm versus 23.4 +/- 2.2 mm, p < 0.01). There were no regional differences in the distribution of either gender or BSA. In the multivariable model, south European patients were seven times more likely to receive a smaller-sized aortic valve (OR = 6.5, 95% CI = 4.82-8.83, p < 0.01), and thus the odds of developing patient-prosthesis mismatch were increased two-fold in southern European patients (OR = 1.9, 95% CI = 1.25-2.80, p = 0.02). However, neither geographic distribution nor valve size were significantly associated with operative mortality. CONCLUSION: The study results demonstrated differences in implanted aortic valve size, between the participating northern and southern European countries. Imbalances in the prevalence of rheumatic heart disease, health resource availability and variations in surgical practice throughout Europe might be possible etiological causes.

Guideline on antiplatelet and anticoagulation management in cardiac surgery.

This document presents a professional view of evidence-based recommendations around the issues of antiplatelet and anticoagulation management in cardiac surgery. It was prepared by the Audit and Guidelines Committee of the European Association for Cardio-Thoracic Surgery (EACTS). We review the following topics: evidence for aspirin, clopidogrel and warfarin cessation prior to cardiac surgery; perioperative interventions to reduce bleeding including the use of aprotinin and tranexamic acid; the use of thromboelastography to guide blood product usage; protamine reversal of heparin; the use of factor VIIa to control severe bleeding; anticoagulation after mechanical, tissue valve replacement and mitral valve repair; the use of antiplatelets and clopidogrel after cardiac surgery to improve graft patency and reduce thromboembolic complications and thromboprophylaxis in the postoperative period. This guideline is subject to continuous informal review, and when new evidence becomes available. The formal review date will be at 5 years from publication (September 2013).

A randomized controlled trial of cell salvage in routine cardiac surgery.

BACKGROUND: Previous trials have indicated that cell salvage may reduce allogeneic blood transfusion during cardiac surgery, but these studies have limitations, including inconsistent use of other blood transfusion-sparing strategies. We designed a randomized controlled trial to determine whether routine cell salvage for elective uncomplicated cardiac surgery reduces blood transfusion and is cost effective in the setting of a rigorous transfusion protocol and routine administration of antifibrinolytics. METHODS: Two-hundred-thirteen patients presenting for first-time coronary artery bypass grafting and/or cardiac valve surgery were prospectively randomized to control or cell salvage groups. The latter group had blood aspirate during surgery and mediastinal drainage the first 6 h after surgery processed in a cell saver device and autotransfused. All patients received tranexamic acid and were subjected to an algorithm for red blood cell and hemostatic blood factor transfusion. RESULTS: There was no difference between the two groups in the proportion of patients exposed to allogeneic blood (32% in both groups, relative risk 1.0 P = 0.89). At current blood products and cell saver prices, the use of cell salvage increased the costs per patient by a minimum of $103. When patients who had mediastinal re-exploration for bleeding were excluded (as planned in the protocol), significantly fewer units of allogeneic red blood cells were transfused in the cell salvage compared with the control group (65 vs 100 U, relative risk 0.71 P = 0.04). CONCLUSION: In patients undergoing routine first-time cardiac surgery in an institution with a rigorous blood conservation program, the routine use of cell salvage does not further reduce the proportion of patients exposed to allogeneic blood transfusion. However, patients who do not have excessive bleeding after surgery receive significantly fewer units of blood with cell salvage. Although the use of cell savage may reduce the demand for blood products during cardiac surgery, this comes at an increased cost to the institution.

Perception and reporting of cardiac surgical performance.

The high level of interest in surgical outcomes has led to the publication of mortality rates in the public domain. In cardiac surgery, the availability of quite sophisticated risk assessment has allowed these outcomes to be adjusted for risk. The European System for Cardiac Operative Risk Evaluation is a widely recognized and used risk scoring system and has been used and validated throughout Europe and beyond. The logistic version is now the most commonly applied, but recalibration may be required. The methodology and statistics for measuring risk-adjusted performance are available, and regular audit and performance monitoring should be carried out in all cardiac surgical units. In the United Kingdom, risk-adjusted outcomes are available and regularly updated on the Internet. Presentation of data may be improved by the use of variable life-adjusted display curves. League tables for crude mortality can be misleading and should be avoided. When properly conducted, the measurement of risk-adjusted surgical outcomes should improve quality control and decision making and allow early identification of poor performance. Quality monitoring in medicine is a priority, and similar methods can be employed in other specialties, including anesthesia, by establishing and analyzing risk-stratified outcome data sets.

Concomitant atrial fibrillation surgery: worth the effort?

Concomitant surgery for atrial fibrillation is a conceptually and clinically difficult area of cardiac surgical decision making. This review introduces the pathophysiological background, provides insight and guidance for cardiac surgeons on some of the conflicting evidence and claims, and explores the fields in which further research may help elucidate a cardiac surgical clinical strategy for tackling this common and potentially lethal form of arrhythmia.

Statistical Primer: developing and validating a risk prediction model.

A risk prediction model is a mathematical equation that uses patient risk factor data to estimate the probability of a patient experiencing a healthcare outcome. Risk prediction models are widely studied in the cardiothoracic surgical literature with most developed using logistic regression. For a risk prediction model to be useful, it must have adequate discrimination, calibration, face validity and clinical usefulness. A basic understanding of the advantages and potential limitations of risk prediction models is vital before applying them in clinical practice. This article provides a brief overview for the clinician on the various issues to be considered when developing or validating a risk prediction model. An example of how to develop a simple model is also included.

Amaze: a randomized controlled trial of adjunct surgery for atrial fibrillation.

OBJECTIVES: Atrial fibrillation (AF) reduces survival and quality of life (QoL). It can be treated at the time of major cardiac surgery using ablation procedures ranging from simple pulmonary vein isolation to a full maze procedure. The aim of this study is to evaluate the impact of adjunct AF surgery as currently performed on sinus rhythm (SR) restoration, survival, QoL and cost-effectiveness. METHODS: In a multicentre, Phase III, pragmatic, double-blinded, parallel-armed randomized controlled trial, 352 cardiac surgery patients with >3 months of documented AF were randomized to surgery with or without adjunct maze or similar AF ablation between 2009 and 2014. Primary outcomes were SR restoration at 1 year and quality-adjusted life years at 2 years. Secondary outcomes included SR at 2 years, overall and stroke-free survival, medication, QoL, cost-effectiveness and safety. RESULTS: More ablation patients were in SR at 1 year [odds ratio (OR) 2.06, 95% confidence interval (CI) 1.20-3.54; P = 0.009]. At 2 years, the OR increased to 3.24 (95% CI 1.76-5.96). Quality-adjusted life years were similar at 2 years (ablation - control -0.025, P = 0.6319). Significantly fewer ablation patients were anticoagulated from 6 months postoperatively. Stroke rates were 5.7% (ablation) and 9.1% (control) (P = 0.3083). There was no significant difference in stroke-free survival [hazard ratio (HR) = 0.99, 95% CI 0.64-1.53; P = 0.949] nor in serious adverse events, operative or overall survival, cardioversion, pacemaker implantation, New York Heart Association, EQ-5D-3L and SF-36. The mean additional ablation cost per patient was £3533 (95% CI £1321-£5746). Cost-effectiveness was not demonstrated at 2 years. CONCLUSIONS: Adjunct AF surgery is safe and increases SR restoration and costs but not survival or QoL up to 2 years. A continued follow-up will provide information on these outcomes in the longer term. Study registration: ISRCTN82731440 (project number 07/01/34).