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An adsorption calorimeter for studies on well-defined single crystal surfaces under ultrahigh vacuum conditions is now available, based on supersonic molecular beam dosing onto ultrathin metal single crystals. Here we discuss the relationship between the calorimetric heat of adsorption as measured in this system and the related parameters: the differential heat of adsorption, the isosteric heat, and the Arrhenius desorption energy. Coverage-dependent calorimetric heats of adsorption and sticking probabilities for CO on Ni{111}, {110}, and {100} are presented, and comparisons made with literature values for isosteric heats and Arrhenius desorption energies. At intermediate coverages some significant discrepancies occur which are attributed to a temperature-dependent adlayer structure. By combining sticking probability with heat measurements at high coverage, at 300 K, where significant desorption occurs, the desorption preexponential has been accurately determined; differential entropies of adsorption are also obtained. Differences in initial heats of adsorption and in the coverage dependencies for the three crystal planes are discussed, particularly in relation to surface stoichiometry, and to CO–CO interactions. [ABSTRACT FROM AUTHOR]

Abstract Introduction Prosthetic valve thrombosis is a rare but life-threatening condition that requires careful evaluation and prompt treatment. While surgical intervention remains the gold standard, thrombolytic therapy is now emerging as a potential substitute. Various thrombolytic treatments including streptokinase, urokinase and recombinant tissue plasminogen activators have been reported with variable success rates. However, the data on the use of tenecteplase (a synthetic tissue plasminogen activator) is limited. Case presentation A 44-year-old Middle Eastern man with a previously implanted prosthetic mitral valve presented with exertional dyspnea and orthopnea. Investigations revealed a thrombosed prosthetic mitral valve. Successful thrombolysis was achieved using tenecteplase which lead to the complete restoration of valve function with no risk to the patient. Conclusion Prosthetic valve thrombosis is a rare but life threatening condition, the diagnosis of which requires a high index of suspicion. Tenecteplase can be used successfully in the management of such cases. It has proved to be useful with no extra risk to the patient.

Acute mitral regurgitation (MR) secondary to papillary muscle rupture is a rare mechanical complication of acute myocardial infarction occurring in 0.05-0.26% of all cases of myocardial infarction. The only treatment is emergency mitral valve surgery with high operative mortality reaching up to 39%. The use of extracorporeal membrane oxygenator (ECMO) as a stabilization strategy and a bridge to recovery may potentially improve the outcome of such cases. Here, we report a case of acute MR presenting with cardiogenic shock and severe hypoxia that required insertion of veno-veno-arterial ECMO initially and followed by emergency mitral valve replacement. This strategy proved useful with full recovery of the patient., Competing Interests: None declared., (Published by Oxford University Press and JSCR Publishing Ltd. © The Author(s) 2024.)

Gerbode defect is a rare defect describing a left ventricle to right atrium shunt with symptoms dependent on the size and degree of the shunt. It is either a congenital defect detected in infancy, or an acquired case reported in older age. Diagnosis by means of echocardiography and cardiac magnetic resonance imaging is of paramount importance before surgical correction is contemplated to achieve a good prognosis.

Electrical storm is a fatal condition unless aborted. Various treatments are available, each with its own limitations. Here, we present a case in which all forms of therapy failed except sympathectomy, which terminated the storm successfully.

Antiphospholipid syndrome is characterized by recurrent spontaneous abortion, recurrent arterial/venous thrombosis, and thrombocytopenia. The presentation of an atrial mass mimicking a myxoma in this syndrome is exceedingly rare, leading to misdiagnosing of the condition and further risking recurrence due to lack of anticoagulation. In this report, we present such a case that was mistakenly thought to be a myxoma.

Aims: To evaluate the potential therapeutic utility of histone deacetylase inhibitors (HDACi) in targeting VEGF receptors in non-small-cell lung cancer., Materials & Methods: Non-small-cell lung cancer cells were screened for the VEGF receptors at the mRNA and protein levels, while cellular responses to various HDACi were examined., Results: Significant effects on the regulation of the VEGF receptors were observed in response to HDACi. These were associated with decreased secretion of VEGF, decreased cellular proliferation and increased apoptosis which could not be rescued by addition of exogenous recombinant VEGF. Direct remodeling of the VEGFR1 and VEGFR2 promoters was observed. In contrast, HDACi treatments resulted in significant downregulation of the Neuropilin receptors., Conclusion: Epigenetic targeting of the Neuropilin receptors may offer an effective treatment for lung cancer patients in the clinical setting.

Background and Aim: With the advancement of percutaneous coronary interventions (PCIs), more patients with diffuse coronary artery disease are referred for coronary artery bypass graft (CABG) surgery. The use of coronary endarterectomy may be useful in such cases. We reviewed our experience with left anterior descending artery endarterectomy as an adjunct to conventional CABG., Methods: Between June 2005 and 2011, 58 consecutive patients underwent left anterior descending artery endarterectomy as an adjunct to CABG. These were matched to 58 cases based on age, gender, and Parsonnet score. All data were collected prospectively in a departmental database. Postoperative complications and in-hospital mortality were analyzed. Survival curves were produced., Results: There was one death in the endarterectomy group (1.7%) from liver failure. There was no significant difference in postoperative complications (especially perioperative myocardial infarction) between the two groups with similar hospital mortality. Computed tomography (CT) angiography was performed in 24 patients with endarterectomy (41%), which showed 100% patency of the left internal mammary artery graft to the left anterior descending artery. Survival and freedom from intervention at a mean follow-up of 4.2 years were similar., Conclusions: In patients with diffuse disease, the use of endarterectomy is a safe technique with no increase in short-term morbidity or mortality. Mid-term results are similar to nonendarterectomized patients. This technique is useful in patients with diffuse coronary artery disease., (© 2013 Wiley Periodicals, Inc.)

Atrial fibrillation remains the commonest arrhythmia encountered in cardiac surgery. Data on the effect of preoperative atrial fibrillation on postoperative outcome remain limited. We sought to assess the effects preoperative atrial fibrillation on patients' outcome following cardiac surgery. This is a retrospective review of prospectively collected departmental data of all patients who underwent cardiac surgery over 8-year period. Our cohort consisted of 3777 consecutive patients divided into atrial fibrillation (n = 413, 11%) and sinus rhythm (n = 3364, 89%). Postoperative complications and in-hospital mortality were analysed. Univariate analysis showed significantly increased mortality and major complications in atrial fibrillation compared to sinus rhythm patients. Using multiple logistic regression analysis and after accounting for Euro SCORE as a confounding variable, we found that preoperative atrial fibrillation significantly increases the risk of mortality (OR 1.7), low cardiac output state (OR 1.3), prolonged ventilation (OR 1.4), infective complication (OR 1.5), gastrointestinal complications (OR 2.0), and intensive care unit readmission (OR 1.6). Preoperative atrial fibrillation in cardiac surgery patients increases their risk of mortality and major complications following cardiac surgery. Surgical strategies such as Cox-Maze procedure may be beneficial in these patients.

Objective: The outcome of patients with solitary kidney undergoing on-pump cardiac surgery is unknown. We sought to assess the in-hospital mortality and complications in these patients compared with patients with normal renal function., Methods: This is a retrospective review of prospectively collected data over an 8-year period of all patients who underwent cardiac surgery. Our cohort consisted of 3363 consecutive patients divided into: solitary kidney (n=31, 0.9%) and normal kidneys (n=3332, 99.1%). Postoperative complications and in-hospital mortality were analysed., Results: Solitary kidney patients had higher incidence of renal failure (26% vs 5%, p-value<0.001), higher incidence of gastrointestinal complications (10% vs 1%, p-value 0.009) and higher blood transfusions (74% vs 43%, p-value<0.001) compared with patients with normal kidneys. There was an increased length of both intensive care unit stay (3.8 vs 2.2 days, p-value 0.031) and hospital stay (15.6 vs 8.5 days, p-value 0.026) among patients with solitary kidney compared with normal kidney patients. Multivariate analysis showed that solitary kidney is an independent predictor of postoperative renal failure (odds ratio (OR) 7.1 (95%CI 3.1-16.6)), gastrointestinal complications (OR 8.5 (95%CI 2.5-29.4)) and blood transfusion (OR 3.8 (95%CI 1.6-9.0)) after adjusting for age and gender. In-hospital mortality, however, was similar in both groups., Conclusion: Although solitary kidney patients have similar short-term mortality as normal kidney patients, the rates of postoperative renal failure, gastrointestinal complications and blood transfusion are significantly higher among solitary kidney patients. Our findings have important clinical implications and prior knowledge of such entity with appropriate risk stratification at admission could help in reducing the risk of these potential complications., (Copyright © 2011 European Association for Cardio-Thoracic Surgery. Published by Elsevier B.V. All rights reserved.)

We assessed the presentation and mechanisms of blunt chest injuries sustained in different age groups, and the impact on management options. We retrospectively reviewed the records of 486 patients with blunt chest trauma who were treated between 2004 and 2007. They were stratified into 3 age groups: pediatric, adult, and elderly. Clinical data, mechanism of injury, associated injuries, treatment strategies, and mortality were analyzed. The majority of patients were male (86%), and the largest age group was 12-60-years old (79%). Motor vehicle accidents accounted for 93% of cases. Isolated chest injuries were more common than combined injuries (69% vs. 31%). Tube thoracostomy was required in 39% of patients, predominantly in the elderly age group. Combined injuries involved bone fractures (21%), head (5%), and abdominal trauma (5%). Most blunt chest injuries were treated conservatively (95.5%). Open thoracotomy was required in 4.5% for clotted hemothorax (3.7%), empyema (0.6%), and massive air leak (0.2%). Mortality was 1%, predominantly in the adult group (0.8%). Blunt thoracic injuries are a major cause of morbidity and mortality. As the majority of such injuries are related to motor vehicle accidents, preventative strategies should be enforced.

Objectives: Although previous studies have shown increased mortality in renal dysfunction patients undergoing cardiac surgery, there is lack of data on the pattern of postoperative complications that occur in such patients and their distribution among dialysis and non-dialysis dependent renal dysfunction., Methods: This is a retrospective review of prospectively collected data over 8 year period of cardiac surgery patients. Our cohort consisted of 3598 consecutive patients divided into: normal kidneys (n = 3276, 91%), renal dysfunction (n = 277, 8%) and dialysis (n = 45, 1%). Postoperative complications and mortality were analysed. Multivariate analysis was conducted to adjust for the potential confounders in the association between renal dysfunction and postoperative complications., Results: Univariate analysis showed increased risk of the following complications among renal dysfunction and dialysis patients: low cardiac output, arrhythmias, reoperation, prolonged ventilation, readmission to intensive care, blood transfusion and prolonged hospital stay. Mortality rate was highest in dialysis patients compared to renal dysfunction and normal kidney patients (11% vs. 7% vs. 3%, respectively p-value <0.001). Multivariate analysis showed that renal dysfunction with or without dialysis is an independent predictor of postoperative low cardiac output, blood transfusion, prolonged ventilation, and mortality. The odd ratios were higher for dialysis than non-dialysis dependent patients. This effect persisted after adjusting for potential confounders such as age and gender., Conclusion: The presence of renal dysfunction preoperatively increases the rate of postoperative complications and mortality following cardiac surgery. Prior knowledge of these complications can help in developing preventative strategies to reduce the associated risk., (Copyright © 2010 Surgical Associates Ltd. Published by Elsevier Ltd. All rights reserved.)

Objectives: We sought to assess the effects of aortic cross-clamp time (XCL) on outcome following cardiac surgery in low- and high-risk patients., Methods: This is a retrospective review of prospectively collected departmental data of all patients who underwent cardiac surgery over 8-year period. Our cohort consisted of 3799 consecutive patients subdivided into low-risk (Euro SCORE < 6, n = 2691, 71%) and high-risk (Euro SCORE ≥ 6, n = 1108, 29%). Each class was further stratified into three groups based on their corresponding XCL time. Group 1 (XCL ≤ 60 min), group 2 (XCL > 60 but ≤ 90 min) and group 3 (XCL >90 min). Postoperative morbidity and in-hospital mortality were analysed., Results: Univariate analysis showed the following to be significantly associated with increased XCL time in both low- and high-risk patients: low cardiac output, prolonged ventilation time, renal complications, prolonged hospital stay, blood transfusion and increased mortality (p < 0.05). By using multiple logistic regression, aortic XCL time >60 min was independent risk factor for low cardiac output, prolonged ventilation, renal complication, blood transfusion, mortality and prolonged hospital stay in both groups. By using XCL time as a continuous variable, an incremental increase of 1 min interval in XCL time was associated with a 2% increase in mortality in both groups., Conclusion: Prolonged cross-clamp time significantly correlates with major post-operative morbidity and mortality in both low- and high-risk patients. This effect increases with increasing XCL time. Prior knowledge on this effect can help in preventing some of these complications., (Copyright © 2010 Surgical Associates Ltd. Published by Elsevier Ltd. All rights reserved.)

Smoking is reported to increase the risk of arrhythmias. However, there are limited data on its effects on arrhythmias following coronary artery bypass graft (CABG). This is a retrospective review of a prospective database of all CABG patients over an eight-year period. Our cohort (n=2813) was subdivided into: current (n=1169), former (n=837), and non-smokers (n=807). Predictors of arrhythmias following CABG in relation to smoking status were analysed. Atrial arrhythmias occurred in 942 patients (33%). Ventricular arrhythmias occurred in 48 patients (2%) and high-grade atrioventricular block occurred in five patients (0.2%). Arrhythmias were lower in current smokers than former and non-smokers (29% vs. 40% vs. 39%, respectively P<0.001). Logistic regression analysis showed 30% arrhythmia risk reduction in smokers compared to non-smokers [odds ratio (OR) 0.7, 95% confidence intervals (CI) 0.5-0.8] and this effect persisted after accounting for potential confounders while former smokers had the same risk as non-smokers (OR 1.04, CI 0.9-1.3). There were no significant differences in mortality. Smokers are less prone to develop arrhythmias following CABG. This paradox effect is lost in former smokers. This effect is possibly due to a lower state of hyper adrenergic stimulation observed in smokers than non-smokers following the stress of surgery.

Lower limb compartment syndrome following coronary artery bypass surgery is a rare complication that is easily overlooked. Here we report a case of lower limb compartment syndrome that was diagnosed and treated promptly in a 53-year-old man, thereby preventing a potentially lethal outcome.

Atrial myxomas are rare tumors that require surgical excision. However, in the presence of a severely calcified ascending aorta, such excision becomes rather challenging and difficult. Here we report a case of a left atrial myxoma in a 64-year-old woman with an extensively calcified aorta that was successfully excised using cardiopulmonary bypass beating-heart technique without the need for cardioplegic cardiac arrest and aortic cross-clamping. The use of this technique proved useful with no increased risk incurred to the patient.

Background: Cyclooxygenase (COX)-2 is frequently overexpressed in non-small cell lung cancer (NSCLC) and results in increased levels of prostaglandin E2 (PGE(2)), an important signalling molecule implicated in tumourigenesis. PGE(2) exerts its effects through the E prostanoid (EP) receptors (EPs1-4)., Methods: The expression and epigenetic regulation of the EPs were evaluated in a series of resected fresh frozen NSCLC tumours and cell lines., Results: EP expression was dysregulated in NSCLC being up and downregulated compared to matched control samples. For EPs1, 3 and 4 no discernible pattern emerged. EP2 mRNA however was frequently downregulated, with low levels being observed in 13/20 samples as compared to upregulation in 5/20 samples examined. In NSCLC cell lines DNA CpG methylation was found to be important for the regulation of EP3 expression, the demethylating agent decitabine upregulating expression. Histone acetylation was also found to be a critical regulator of EP expression, with the histone deacteylase inhibitors trichostatin A, phenylbutyrate and suberoylanilide hydroxamic acid inducing increased expression of EPs2-4. Direct chromatin remodelling was demonstrated at the promoters for EPs2-4., Conclusions: These results indicate that EP expression is variably altered from tumour to tumour in NSCLC. EP2 expression appears to be predominantly downregulated and may have an important role in the pathogenesis of the disease. Epigenetic regulation of the EPs may be central to the precise role COX-2 may play in the evolution of individual tumours.