The Relationship Between Preoperative Hemoglobin Concentration, Use of Hospital Resources, and Outcomes in Cardiac Surgery.

OBJECTIVES: Preoperative anemia is an established risk factor associated with adverse perioperative outcomes after cardiac surgery. However, limited information exists regarding the relationship between preoperative hemoglobin concentration and outcomes. The aim of this study was to investigate how outcomes are affected by preoperative hemoglobin concentration in a cohort of patients undergoing cardiac surgery. DESIGN: A retrospective, observational cohort study. SETTING: A single-center tertiary referral hospital. PARTICIPANTS: The study comprised 1,972 adult patients undergoing elective and nonelective cardiac surgery. INTERVENTIONS: The independent relationship of preoperative hemoglobin concentration was explored on blood transfusion rates, return to the operating room for bleeding and/or cardiac tamponade, postoperative intensive care unit (ICU) and in-hospital length of stay, and mortality. MEASUREMENTS AND MAIN RESULTS: The overall prevalence of anemia was 32% (629/1,972 patients). For every 1-unit increase in hemoglobin (g/dL), blood transfusion requirements were reduced by 11%, 8%, and 3% for red blood cell units, platelet pools, and fresh frozen plasma units, respectively (adjusted incident rate ratio 0.89 [95% CI 0.87-0.91], 0.92 [0.88-0.97], and 0.97 [0.96-0.99]). For each 1-unit increase in hemoglobin (g/dL), the probability (over time) of discharge from the ICU and hospital increased (adjusted hazard ratio estimates 1.04 [1.00-1.08] and 1.12 [1.12-1.16], respectively). CONCLUSIONS: A lower preoperative hemoglobin concentration resulted in increased use of hospital resources after cardiac surgery. Each g/dL unit fall in preoperative hemoglobin concentration resulted in increased blood transfusion requirements and increased postoperative ICU and hospital length of stay.

Novel Techniques and Technologies for Surgical Aortic Valve Replacement: A Large Retrospective Cohort Analysis.

Background/Objectives: In an era of growing evidence for transaortic valve implantation (TAVI), our research topic was the evaluation of how surgical aortic valve replacements (SAVRs) are performing in terms of short- and long-term outcomes in different risk categories. Methods: This was a single centre, prospective, and observational cohort study of consecutive patients with aortic valve stenosis, undergoing isolated aortic valve replacement using a biological or mechanical prosthesis, Freestyle™ (Medtronic, Minneapolis, MN, USA) graft, homograft, or Ross procedure. The participant data were collected by review of an internal database. The primary endpoints were all-cause operative mortality (in hospital and at 30 days) and late mortality at the follow-up date. The secondary composite endpoint was the incidence of postoperative complications. Results: 1501 patients underwent SAVR; the mean age was 67 years (SD: 12.6). The in-hospital mortality was 1% (n = 16). At a median follow-up of 60 months, the survival rate was 98.7%. The main predictors for mortality were operative urgency and cardiogenic shock. The overall incidence of PPM was 2.3% (n = 34). Patients who underwent Ross procedure were younger (mean age: 20 years (SD: 1.7)), had a lower incidence of postoperative complications, and were all alive at follow-up. Conclusions: SAVR shows an excellent survival rate and a low rate of postoperative complications despite an increasing surgical risk. Recent advancements in technology, like sutureless/rapid deployment prostheses and minimally invasive techniques, are shown to have favourable effects on outcomes.

Cardiolipin synthase is required for Streptomyces coelicolor morphogenesis.

The fluid mosaic model has recently been amended to account for the existence of membrane domains enriched in certain phospholipids. In rod-shaped bacteria, the anionic phospholipid cardiolipin is enriched at the cell poles but its role in the morphogenesis of the filamentous bacterium Streptomyces coelicolor is unknown. It was impossible to delete clsA (cardiolipin synthase; SCO1389) unless complemented by a second copy of clsA elsewhere in the chromosome. When placed under the control of an inducible promoter, clsA expression, phospholipid profile and morphogenesis became inducer dependent. TLC analysis of phospholipid showed altered profiles upon depletion of clsA expression. Analysis of cardiolipin by mass spectrometry showed two distinct cardiolipin envelopes that reflected differences in acyl chain length; the level of the larger cardiolipin envelope was reduced in concert with clsA expression. ClsA-EGFP did not localize to specific locations, but cardiolipin itself showed enrichment at hyphal tips, branch points and anucleate regions. Quantitative analysis of hyphal dimensions showed that the mycelial architecture and the erection of aerial hyphae were affected by the expression of clsA. Overexpression of clsA resulted in weakened hyphal tips, misshaped aerial hyphae and anucleate spores and demonstrates that cardiolipin synthesis is a requirement for morphogenesis in Streptomyces.

Transaortic transcatheter aortic valve implantation for failed surgical aortic valve replacement due to 'porcelain aorta'.

Transcatheter aortic valve implantation (TAVI) is an emerging surgical approach in patients with severe aortic stenosis unsuitable for conventional aortic valve replacement (AVR). TAVI has been performed through both transfemoral and transapical approaches, each with a specific suitability criterion. A transaortic (TAo-TAVI) approach has been recently established at the authors' institution for high-risk patients who are unsuited to the above techniques. Herein, the case is described of a successful aortic valve implantation using TAo-TAVI in a patient with porcelain ascending aorta that was identified as an incidental finding during conventional AVR. The patient recovered well and was discharged home without any complications.

Long-Term Outcomes Following Heart Team Revascularization Recommendations in Complex Coronary Artery Disease.

Background The Heart Team ( HT ) comprises integrated interdisciplinary decision making. Current guidelines assign a Class Ic recommendation for an HT approach to complex coronary artery disease ( CAD ). However, there remains a paucity of data in regard to hard clinical end points. The aim was to determine characteristics and outcomes in patients with complex CAD following HT discussion. Methods and Results This observational study was conducted at St Thomas' Hospital (London, UK). Case mixture included unprotected left main, 2-vessel (including proximal left anterior descending artery) CAD , 3-vessel CAD , or anatomical and/or clinical equipoise. HT strategy was defined as optimal medical therapy ( OMT ) alone, OMT +percutaneous coronary intervention ( PCI ), or OMT +coronary artery bypass grafting. From April 2012 to 2013, 51 HT meetings were held and 398 cases were discussed. Patients tended to have multivessel CAD (74.1%), high SYNTAX (Synergy between PCI with Taxus and Cardiac Surgery) scores (median, 30; interquartile range, 23-39), and average age 69±11 years. Multinomial logistic regression analysis performed to determine variables associated with HT strategy demonstrated decreased likelihood of undergoing PCI compared with OMT in older patients with chronic kidney disease and peripheral vascular disease. The odds of undergoing coronary artery bypass grafting compared with OMT decreased in the presence of cardiogenic shock and left ventricular dysfunction and increased in younger patients with 3-vessel CAD . Three-year survival was 60.8% (84 of 137) in the OMT cohort, 84.3% (107 of 127) in the OMT + PCI cohort, and 90.2% in the OMT +coronary artery bypass grafting cohort (92 of 102). Conclusions In our experience, the HT approach involved a careful selection process resulting in appropriate patient-specific decision making and good long-term outcomes in patients with complex CAD .

A comparison of early redo surgery rates in Mosaic porcine and Perimount bovine pericardial valves.

OBJECTIVES: The objective of this study was to compare rates of redo surgery for the Medtronic Mosaic 305 A Porcine Prosthesis and the Carpentier-Edwards Perimount Pericardial Aortic Bioprosthesis 2900. METHODS: This was a single-centre retrospective observational study. We included all 1018 patients who underwent aortic valve replacement with a Mosaic (n = 216) or Perimount (n = 809) bioprosthesis between October 2000 and August 2008. The total follow-up was 1508 patient-years for the Mosaic valve and 5813 for the Perimount valve. The maximal follow-up and interquartile range were 14.8 and 7.0 years for the Mosaic valve and 15.1 and 5.6 years for the Perimount valve, respectively. A propensity score-weighted version of the Cox model, Kaplan-Meier analysis and multivariate regression model was used. RESULTS: Despite no statistical difference in the number of non-structural valve deterioration cases between valves, redo surgery occurred earlier in 10 (4.6%) Mosaic than for 17 (2.1%) Perimount valves (P = 0.02) and was required for structural valve deterioration in 5 (2.3%) Mosaic valves when compared with 7 (0.9%; P = 0.04) Perimount valves. Four of 5 Mosaic failures occurred before 5 years, whereas all Perimount failures occurred after 5 years. Redo surgery for non-structural valve deterioration occurred in 3 patients with Mosaic valves (1.4%) and no patients with Perimount valves. Surgery for the remaining patients with Perimount valves was due to infection or aortic disease. CONCLUSIONS: Early redo surgery for structural valve degeneration was uncommon but occurred earlier for the Mosaic porcine than the Perimount bovine pericardial replacement aortic valve.

A comparison of two forms of the continuity equation in the Trifecta bovine pericardial aortic valve.

AIM: To compare the classical and simplified form of the continuity equation in small Trifecta valves. METHODS: This is a retrospective analysis of post-operative echocardiograms performed for clinical reasons after implantation of Trifecta bioprosthetic valves. RESULTS: There were 60 patients aged 74 (range 38-89) years. For the valves of size 19, 21 and 23mm, the mean gradient was 11.3, 10.7 and 9.7mmHg, respectively. The effective orifice areas by the classical form of the continuity equation were 1.4, 1.7 and 1.9cm(2), respectively. There was a good correlation between the two forms of the continuity equation, but they were significantly different using a t-test (P<0.00001). Results using the classical form were a mean 0.11 (s.d. 0.18)cm(2) larger than those using the simple formula. CONCLUSION: Haemodynamic function of the Trifecta valve in the small aortic root is good. There are significant differences between the classical and simplified forms of the continuity equation.

Implementation and consistency of Heart Team decision-making in complex coronary revascularisation.

BACKGROUND: A multidisciplinary team (MDT) approach for decision-making in patients with complex coronary artery disease (CAD) is now a class IC recommendation in the European and American guidelines for myocardial revascularisation. The aim of this study was to evaluate the implementation and consistency of Heart Team HT decision-making in complex coronary revascularisation. METHODS: We prospectively evaluated the data of 399 patients derived from 51 consecutive MDT meetings held in a tertiary cardiac centre. A subset of cases was randomly selected and re-presented with the same clinical data to a panel blinded to the initial outcome, at least 6 months after the initial discussion, in order to evaluate the reproducibility of decision-making. RESULTS: The most common decisions included continued medical management (30%), coronary artery bypass grafting (CABG) (26%) and percutaneous coronary intervention (PCI) (17%). Other decisions, such as further assessment of symptoms or evaluation with further invasive or non-invasive tests were made in 25% of the cases. Decisions were implemented in 93% of the cases. On re-discussion of the same data (n=40) within a median period of 9 months 80% of the initial HT recommendations were successfully reproduced. CONCLUSIONS: The Heart Team is a robust process in the management of patient with complex CAD and decisions are largely reproducible. Although outcomes are successfully implemented in the majority of the cases, it is important that all clinical information is available during discussion and patient preference is taken into account.

Minimally Invasive Versus Conventional Aortic Valve Replacement: A Propensity-Matched Study From the UK National Data.

OBJECTIVE: Minimally invasive aortic valve replacement (MIAVR) has been demonstrated as a safe and effective option but remains underused. We aimed to evaluate outcomes of isolated MIAVR compared with conventional aortic valve replacement (CAVR). METHODS: Data from The National Institute for Cardiovascular Outcomes Research (NICOR) were analyzed at seven volunteer centers (2006-2012). Primary outcomes were in-hospital mortality and midterm survival. Secondary outcomes were postoperative length of stay as well as cumulative bypass and cross-clamp times. Propensity modeling with matched cohort analysis was used. RESULTS: Of 307 consecutive MIAVR patients, 151 (49%) were performed during the last 2 years of study with a continued increase in numbers. The 307 MIAVR patients were matched on a 1:1 ratio. In the matched CAVR group, there was no statistically significant difference in in-hospital mortality [MIAVR, 4/307,(1.3%); 95% confidence interval (CI), 0.4%-3.4% vs CAVR, 6/307 (2.0%); 95% CI, 0.8%-4.3%; P = 0.752]. One-year survival rates in the MIAVR and CAVR groups were 94.4% and 94.6%, respectively. There was no statistically significant difference in midterm survival (P = 0.677; hazard ratio, 0.90; 95% CI, 0.56-1.46). Median postoperative length of stay was lower in the MIAVR patients by 1 day (P = 0.009). The mean cumulative bypass time (94.8 vs 91.3 minutes; P = 0.333) and cross-clamp time (74.6 vs 68.4 minutes; P = 0.006) were longer in the MIAVR group; however, this was significant only in the cross-clamp time comparison. CONCLUSIONS: Minimally invasive aortic valve replacement is a safe alternative to CAVR with respect to operative and 1-year mortality and is associated with a shorter postoperative stay. Further studies are required in high-risk (logistic EuroSCORE > 10) patients to define the role of MIAVR.

Cost-effectiveness of preoperative positron emission tomography in ischemic heart disease.

BACKGROUND: Revascularization of patients with ischemic heart disease and poor left ventricular function for surgical procedures is expensive and carries considerable risks, but may improve survival for patients with hibernating myocardium. Positron emission tomography can detect hibernating myocardium, and may be cost-effective if used to select patients for operation. METHODS: An economic model was developed to compare the cost-effectiveness of three management strategies: (1) coronary artery bypass grafting for all patients; (2) using positron emission tomography to select candidates for coronary artery bypass grafting, those without hibernation remaining on medical therapy; and (3) medical therapy for all patients. The model used data from our hospital and the published literature. A sensitivity analysis was also undertaken. RESULTS: Positron emission tomography was cost-effective in selecting patients for operation. In a hypothetical population of 1,000 patients, using positron emission tomography saved marginally more life-years and cost approximately Pound Sterling 3 million less. Using positron emission tomography before coronary artery bypass grafting instead of all patients receiving medical treatment saved lives but was more expensive. The incremental cost per life-year saved was Pound Sterling 77,000. The sensitivity analysis showed that the prevalence of hibernation and the survival rate of patients refused revascularization on the basis of the positron emission tomography scan were the areas most likely to influence cost-effectiveness. CONCLUSIONS: Positron emission tomography may be cost-effective to select patients with poor left ventricular function for coronary artery bypass grafting.

A technical review of the United Kingdom National Adult Cardiac Surgery Governance Analysis 2008-11.

The Society for Cardiothoracic Surgery in Great Britain and Ireland (SCTS) has published named mortality data since 2001. The importance of accurate and robust clinical outcome reporting has been emphasized by a number of high-profile cases in England. In this article, we give a technical review of the United Kingdom National Adult Cardiac Surgery Governance Analysis 2008-11. The statistical and analytical assumptions and methods are discussed in order to add an additional layer of transparency to the clinical governance process and precipitate scrutiny with the aim of optimizing future analyses.

Surgeon length of service and risk-adjusted outcomes: linked observational analysis of the UK National Adult Cardiac Surgery Audit Registry and General Medical Council Register.

OBJECTIVES: To explore the relationship between in-hospital mortality following adult cardiac surgery and the time since primary clinical qualification for the responsible consultant cardiac surgeon (a proxy for experience). DESIGN: Retrospective analysis of prospectively collected national registry data over a 10-year period using mixed-effects multiple logistic regression modelling. Surgeon experience was defined as the time between the date of surgery and award of primary clinical qualification. SETTING: UK National Health Service hospitals performing cardiac surgery between January 2003 and December 2012. PARTICIPANTS: All patients undergoing coronary artery bypass grafts and/or valve surgery under the care of a consultant cardiac surgeon. MAIN OUTCOME MEASURES: All-cause in-hospital mortality. RESULTS: A total of 292,973 operations performed by 273 consultant surgeons (with lengths of service from 11.2 to 42.0 years) were included. Crude mortality increased approximately linearly until 33 years service, before decreasing. After adjusting for case-mix and year of surgery, there remained a statistically significant (p=0.002) association between length of service and in-hospital mortality (odds ratio 1.013; 95% CI 1.005-1.021 for each year of 'experience'). CONCLUSIONS: Consultant cardiac surgeons take on increasingly complex surgery as they gain experience. With this progression, the incidence of adverse outcomes is expected to increase, as is demonstrated in this study. After adjusting for case-mix using the EuroSCORE, we observed an increased risk of mortality in patients operated on by longer serving surgeons. This finding may reflect under-adjustment for risk, unmeasured confounding or a real association. Further research into outcomes over the time course of surgeon's careers is required.

Aspergillus endocarditis: a case of near complete left ventricular outflow obstruction.

A 60-year old woman presented with dyspnoea and fatigue. She was frail and cachectic (BMI 17.5) with a pancytopenia. Previously she had received chemotherapy for chronic lymphatic leukaemia. She relapsed one year ago necessitating a reduced intensity conditioning allogeneic haematopoietic cell transplantation. Subsequently, graft versus host disease required high-dose immunosuppressants. Computerized tomography on admission showed bilateral lung nodules and a suspicious cardiac mass. Bronchial biopsies demonstrated abundant hypae consistent with Aspergillus fumigatus infection. Echocardiography demonstrated a large fungus ball attached to the right coronary cusp of the aortic valve with near complete obliteration of the left ventricular outflow tract. Due to the high risk of embolization this was resected under cardiopulmonary bypass. The mass was attached subvalvularly to the ventricular septal free wall and eroding through it. It peeled off leaving intact aortic leaflets. Unresectable fungal deposits were discovered on the interventricular septum, the left ventricle free wall and posterior aortic wall. High-dose systemic antifungal therapy (Voriconazole and Amphoteracin B) was given for 4 months. After discharge she remained well till a 4-month follow-up, after which she eventually succumbed to her disease. We discuss the clinical difficulties in managing patients with fungal infective endocarditis and present a brief review of cardiac aspergillosis management.

Aortic valve surgery: marked increases in volume and significant decreases in mechanical valve use--an analysis of 41,227 patients over 5 years from the Society for Cardiothoracic Surgery in Great Britain and Ireland National database.

OBJECTIVES: Aortic valve replacement is accepted as a standard treatment for aortic stenosis and regurgitation. To help plan the national requirement for conventional and catheter-based procedures, we have analyzed the Society for Cardiothoracic Surgery in Great Britain and Ireland audit database to look at changes in practice over time. METHODS: All patients undergoing conventional aortic valve replacement with or without coronary artery surgery from April 2004 to March 2009 were included. The main outcome measures were changes in the number, characteristics, operative details, and in-hospital mortality. We have looked particularly at trends and outcomes in elderly and high-risk patients (EuroSCORE of 10 or more) who may now be considered for percutaneous aortic valve insertion. RESULTS: A total of 41,227 patients underwent aortic valve surgery over 5 years with an in-hospital mortality of 4.1%. The annual number increased from 7396 in 2004-2005 to 9333 in 2008-2009, with significant increases (P < .0005) in mean age (68.8-70.2 years), the proportion of patients with aortic stenosis (62.4%-65.1%), octogenarians (13.6%-18.4%), high-risk patients (24.6%-27.7%), and those receiving biological valves (65.4%-77.8%). The incidence of permanent cerebrovascular accident was 1.2% and 1.0% in patients having only an aortic valve replacement. The dialysis rate was 4.5% and the reoperation rate for bleeding was 6.6%. Overall mortality decreased from 4.4% in 2004-2005 to 3.7% in 2008-2009. Survival to a mean follow-up of 2.5 years was 89%. CONCLUSIONS: We have seen a large increase in annual volume of aortic valve replacements, with more patients undergoing surgery for aortic stenosis and an increase in surgery in the elderly and high-risk patients.

Early and late predictors of mortality following on-pump coronary artery bypass graft surgery in the elderly as compared to a younger population.

OBJECTIVE: To identify independent factors associated with early (30-day) mortality and in surviving patients, identify factors for late (1-year) mortality following primary coronary artery bypass graft (CABG) surgery and to test the interaction with age. METHODS: An analysis of a single centre's data contribution to the Society for Cardiothoracic Surgery in Great Britain and Ireland database was performed. Data on consecutive patients aged > or =75 years (n=659) and aged 60-74 years (n=3024) undergoing primary CABG surgery (1999-2005) were analysed. One-year mortality data were collected using the Office of National Statistics (ONS) tracking system. Factors associated with early and late mortality were identified using Cox regression; hazard ratios (HRs) and 95% confidence intervals (CIs) are presented. RESULTS: The proportion of patients aged > or =75 years increased by 10% over 5 years (2000-2005). One-year mortality in the elderly showed a significant linear decrease from 15% to 7% (p=0.01) while mortality in the younger cohort remained static at 2-4%. Early mortality in the elderly group was 5% compared to 1.8% in the younger group (p<0.001), while late mortality was 4.1% vs 1.8%, respectively (p<0.001). Factors independently associated with early mortality were age > or =75 years, HR 2.0 (95% CI 1.28, 3.11); female gender; angina (CSS III-IV); and cardiopulmonary bypass duration >97 minutes. Arrhythmia and renal impairment were risk factors common in both early and late mortality models. Risk factors for late mortality also included ventricular ejection fraction <30%, non-elective surgery and arteriopathy. Age was not an independent risk factor for late mortality. CONCLUSION: Mortality in elderly patients showed a substantial improvement, but remained over twice that of younger patients. The difference in factors associated with early and 1-year morality suggests the need for effective short- and long-term strategies, particularly in the management of chronic diseases such as heart and renal failure.

Experience with Vacuum-assisted closure of sternal wound infections following cardiac surgery and evaluation of chronic complications associated with its use.

OBJECTIVES: We report our experience in use of Vacuum-assisted closure therapy (VAC) in the treatment of poststernotomy wound infection with emphasis on recurrent wound-related problems after use of VAC and their treatment. METHODS: Between July 2000 and June 2003, 2706 patients underwent various cardiac procedures via median sternotomy. Forty-nine patients with postoperative sternal wound infection (1.9%) were managed with VAC. Wounds were classified as either superficial sternal wound infection (28 patients) or deep sternal wound infection (21 patients). In the superficial sternal wound infection group, 23 patients had VAC as definitive treatment (GroupA), while five patients (Group B) had VAC followed by surgical closure. Similarly, in the deep sternal wound infection group, 12 patients had VAC as definitive treatment (Group C), while nine patients had VAC followed by surgical closure (Group D). Patients were discharged after satisfactory wound closure. Upon discharge patients were followed up at interval of three to six months. Recurrent sternal problems when identified were investigated and additional surgical procedures were carried out when necessary. RESULTS: There were nine deaths, all due to unrelated causes except in one patient who died of right ventricular rupture (Group C). Nine patients in Group A had recurrent wound problems of which six had VAC system for > 21 days. Three patients underwent extensive debridement due to sternal osteomyelitis. All eight patients in Group B presented with chronic wound-related problems and underwent multiple debridements. Four patients had laparoscopic omental flaps. In contrast 14 patients (Group B and D) who were treated with shorter duration of VAC followed by either a flap or direct surgical closure, did not present with recurrent problems. CONCLUSION: VAC therapy is a safe and reliable option in the treatment of sternal wound infection. However, prolonged use of VAC system as a replacement for surgical closure of sternal wound appears to be associated with recurrent problems of the sternal wound. Strategy of use of VAC for a short duration followed by early surgical closure appears favorable.