Histology-Validated Dielectric Characterisation of Lung Carcinoma Tissue for Microwave Thermal Ablation Applications.

Microwave thermal ablation is a promising emerging treatment for early-stage lung cancer. Applicator design optimisation and treatment planning rely on accurate knowledge of dielectric tissue properties. Limited dielectric data are available in the literature for human lung tissue and pulmonary tumours. In this work, neoplastic and non-neoplastic lung dielectric properties are characterised and correlated with gross and histological morphology. Fifty-six surgical specimens were obtained from twelve patients undergoing lung resection for lung cancer in University Hospital of Galway, Ireland. Dielectric spectroscopy in the microwave frequency range (500 MHz-8.5 GHz) was performed on the ex vivo lung specimens with the open-ended coaxial probe technique (in the Department of Pathology). Dielectric data were analysed and correlated with the tissue histology. The dielectric properties of twelve lung tumours (67% non-small cell carcinoma (NSCC)) and uninvolved lung parenchyma were obtained. The values obtained from the neoplastic lung specimens (relative permittivity: 52.0 ± 5.4, effective conductivity: 1.9 ± 0.2 S/m, at 2.45 GHz) were on average twice the value of the non-neoplastic lung specimens (relative permittivity: 28.3 ± 6.7, effective conductivity: 1.0 ± 0.3 S/m, at 2.45 GHz). Dense fibrosis was comparable with tumour tissue (relative permittivity 49.3 ± 4.6, effective conductivity: 1.8 ± 0.1 S/m, at 2.45 GHz).

Impact of on-pump and off-pump coronary artery bypass grafting on 10-year mortality versus percutaneous coronary intervention.

OBJECTIVES: The very long-term mortality of off-pump and on-pump coronary artery bypass grafting (CABG) versus percutaneous coronary intervention (PCI) in a randomized complex coronary artery disease population is unknown. This study aims to investigate the impact of on-pump and off-pump CABG versus PCI on 10-year all-cause mortality. METHODS: The SYNTAX trial randomized 1800 patients with three-vessel and/or left main coronary artery disease to PCI or CABG and assessed their survival at 10 years. In this sub-study, the hazard of mortality over 10 years was compared according to the technique of revascularization: on-pump CABG (n = 725), off-pump CABG (n = 128) and PCI (n = 903). RESULTS: There was substantial inter-site variation in the use of off-pump CABG despite baseline characteristics being largely homogeneous among the 3 groups. The crude rate of mortality was significantly lower following on-pump CABG versus PCI [25.6% vs 28.4%, hazard ratio (HR) 0.79, 95% confidence interval (CI) 0.65-0.96], while it was comparable between off-pump CABG and PCI (28.5% vs 28.4%, HR 0.98, 95% CI 0.69-1.40). After adjusting for the 9 variables included in the SYNTAX score II 2020, 10-year mortality remained significantly lower with on-pump CABG than PCI (HR 0.75 against PCI, P = 0.009). CONCLUSIONS: In the SYNTAXES trial, 10-year mortality adjusted for major confounders was significantly lower following on-pump CABG compared to PCI. There was no evidence for unadjusted difference between off-pump CABG and PCI, although the unadjusted estimated HR had a wide CI. Site heterogeneity in the technique used in bypass surgery has had measurable effects on treatment performance.

Lung Cancer resection in the absence of pre-operative histology: The Accuracy of Multidisciplinary Team Consensus.

BACKGROUND: Lung resection remains the gold-standard of treatment for non-small cell lung cancer (NSCLC). British Thoracic Society (BTS) guidelines recommends the pursuit of pre-operative histological diagnosis and staging where possible. In the absence of pre-operative histology, surgical treatment can be offered in conjunction with multidisciplinary team (MDT) and patient consensus. We undertook a single-centre analysis of the accuracy of the lung cancer MDT in recommending surgical resection for those with suspected lung malignancy in the absence of pre-operative histological diagnosis over a six-year period. METHODS: A retrospective review was performed of patients undergoing any pulmonary oncological resection with therapeutic intent without pre-operative histological diagnosis at the recommendation of the lung cancer MDT in our unit between May 2016 and July 2022. RESULTS: 270 consecutive patients underwent lung resection for a lung nodule of indeterminate significance. This accounted for 45% of the oncological resections performed over this period. The mean age of the cohort was 67.9 years, and 47.4% were male. Overall, 10% of resected specimens (n = 27) were benign on final histopathology. 93% of those undergoing a lobectomy received a malignant diagnosis. Across the study cohort, surgical resection was well tolerated with a low complication rate. CONCLUSIONS: Lung cancer resection in the absence of pre-operative histological diagnosis is feasible in a select patient cohort. This approach requires an experienced multi-disciplinary team and careful patient counselling. Our study demonstrates this adapted approach to be a pragmatic solution to the management of indeterminate pulmonary nodules in centres where biopsy is not routinely available due to existing constraints on the health system.

Impact of periprocedural major adverse events on 10-year mortality after revascularisation.

BACKGROUND: The long-term prognostic impact of a composite of periprocedural major adverse events (PMAE) following revascularisation for patients with complex coronary artery disease (CAD) has not yet been established. AIMS: This study aimed to assess the impact on 10-year mortality of non-fatal PMAE following percutaneous coronary intervention (PCI) or coronary artery bypass grafting (CABG). Other objectives were to evaluate 1) whether PMAE affect mortality predicted by the SYNTAX score II 2020 (SSII-2020) and 2) whether optimal medical therapy (OMT) positively affects the prognosis of patients with non-fatal PMAE. METHODS: The association between 10-year mortality and non-fatal PMAE occurring within 30 days of PCI or CABG in patients with three-vessel disease and/or left main disease enrolled in the SYNTAXES study was investigated. RESULTS: The main findings are that non-fatal PMAE occurred less frequently following PCI than CABG (11.2% vs 28.2%; p<0.001) and that non-fatal PMAE were an independent predictor of all-cause mortality in the first year post-procedure, but not at 5 or 10 years, in both treatment modalities. PMAE substantially alter the individual predictions of 10-year mortality by the SSII-2020. In patients with non-fatal PMAE, OMT may provide survival benefits during the first year post-procedure as well as in the long term. CONCLUSIONS: In patients with complex CAD, non-fatal PMAE were more common following CABG than PCI, but their prognostic impact was similar, being significant in the first year and then diminishing out to 10 years. Patients with non-fatal PMAE may therefore require more careful follow-up and additional preventive treatment in the first year post-procedure.

Endoscopic vein harvesting: a guide for approaching difficult cases and assessing patients preoperatively.

Coronary artery bypass grafting remains the most commonly performed cardiac surgical procedure worldwide. The long saphenous vein still presides as the first choice conduit as a second graft in multivessel coronary artery bypass grafting surgery. Traditionally, the long saphenous vein has been harvested with an open approach which can potentially result in significant wound complications in certain circumstances. Endoscopic vein harvesting is a minimally invasive vein harvesting technique, which requires a single 2-3 cm incision and is associated with a quicker return to normal daily activities, decreased wound complications and better quality of life in the longer term. There is a learning curve associated with endoscopic vein harvesting adoption and there are certain patient factors that can prove to be challenging when adopting an endoscopic approach. This commentary aims to provide a concise guide of certain challenging patient factors that operators may encounter during endoscopic vein harvesting, and how to approach these patients in both the preoperative and intraoperative settings. We suggest that with appropriate planning and awareness of the challenging patient factors and problematic venous anatomy that exists, the operator can consistently formulate a strategy for ensuring a successful endoscopic harvest.

Bronchogenic cyst: a rare case of malignant transformation.

Bronchogenic cysts are rare cystic malformations of the respiratory tract with prevalence that is largely unknown. They are most commonly diagnosed incidentally in asymptomatic patients. While surgical resection is the mainstay of treatment for patients who are symptomatic, the treatment course for patients without symptoms is less clear. We describe the case of an initially asymptomatic elderly man who was found to have a bronchogenic cyst on routine surveillance imaging, culminating in the rapid enlargement and malignant transformation of the cyst, ultimately resulting in a technically difficult and challenging surgical resection. The malignant transformation of these bronchogenic cysts is exceedingly rare, with only a few well-documented cases reported in the literature. To our knowledge, this is the first report of a squamous cell carcinoma arising from a bronchogenic cyst in the paratracheal region.

The use of neutrophil lymphocyte ratio to predict complications post cardiac surgery.

BACKGROUND: Cardiac surgery remains the gold standard treatment for select cohorts of patients with coronary artery and valvular heart diseases. It induces an acute systemic inflammatory response due to cardiopulmonary bypass (CPB), myocardial arrest, and surgical trauma. There is growing evidence that increased inflammation leads to greater complications and poorer outcomes for patients post cardiac surgery. Neutrophil/lymphocyte ratio (NLR) is a promising marker of inflammation. This study assessed if NLR could predict postoperative atrial fibrillation and acute kidney injury after cardiac surgery. METHODS: A retrospective review of patients undergoing first-time on-pump cardiac surgery was performed. Postoperative atrial fibrillation and acute kidney injury within 7 days of surgery was recorded. Preoperative, day 1, and day 2 NLR were recorded. Potential confounders such as age, sex, comorbidities, and operative factors were included in univariate analysis. Backwards stepwise multivariate regression analysis was performed to identify independent predictors of these complications. RESULTS: Nine hundred and six patients were included for analysis. Higher preoperative NLR was significantly associated with postoperative atrial fibrillation. Day 1 and day 2 NLR were associated with postoperative atrial fibrillation in analyses including all patients. Older age, male gender, preexisting atrial arrhythmias, and higher EuroSCORE II also had a significant association. Diabetes mellitus was protective for postoperative arrhythmias. Preoperative NLR was not significantly associated with acute kidney injury. Day 2 NLR, older age, higher EuroSCORE II, and longer CPB time were independently associated with acute kidney injury post cardiac surgery. CONCLUSIONS: Higher preoperative and postoperative NLRs are associated with higher rates of complications post cardiac surgery.

Posterior mediastinal Müllerian cyst: a rare cause of pain in a young woman.

Thoracic pain in a young woman carries a wide differential diagnosis. We present the case of a 37-year-old woman who presented with thoracic pain due to a posterior mediastinal Müllerian cyst. Excision was performed by left uniportal video-assisted thoracoscopic surgery. This is the first report to describe thoracic pain that resolved with excision of the cyst.

Complete right ventricular obstruction caused by a giant cardiac myxoid sarcoma.

Myxoid sarcoma is a very rare variant of primary malignant sarcoma of the heart, which presents like a myxoma. We describe the case of 21-year-old man with a giant myxoid sarcoma occupying most of the right ventricle. He underwent emergency surgery to resect the tumor and replace the tricuspid valve which was infiltrated. Chemotherapy and radiotherapy were given postoperatively.

Depicting adverse events in cardiac theatre: the preliminary conception of the RECORD model.

Human error is a byproduct of the human activity and may results in random unintended events; they may have major consequences when it comes to delivery of medicine. Furthermore the causes of error in surgical practice are multifaceted and complex. This article aims to raise awareness for safety measures in the cardiac surgical room and briefly "touch upon" the human factors that could lead to adverse outcomes. Finally, we describe a model that would enable us to depict and study adverse events in the operating theatre.

Ultrasound mapping of the long saphenous vein in coronary artery bypass graft surgery.

Long saphenous vein is the most common conduit utilized for surgical coronary revascularization. Ultrasound-assisted vein assessment is superior to traditional clinical examination of the long saphenous vein in discerning path and suitability for use as a conduit. Preoperative ultrasound mapping of the long saphenous vein is easy and rapidly accomplished allowing optimal surgical site selection, avoiding unnecessary surgical dissection and potential wound complications. We describe the technique of ultrasound mapping of the long saphenous vein and its application to conduit harvest in coronary artery bypass graft (CABG) surgery.

Is there any further advantage of using more than one internal mammary artery? Literature review and analysis.

The use of the internal mammary artery reduces the incidence of late adverse effects and improves survival after coronary artery bypass grafting. Therefore, internal mammary artery grafts ought to be used in all patients undergoing coronary artery bypass grafting (level II evidence), although in the UK, only 95% of the patients receive an internal mammary artery graft. This is due to factors such as poor left ventricular function, old age, previous radiation to the thoracic cavity, or emergency surgery. As there are biological similarities between the left and right internal mammary artery, one can extrapolate that the use of 2 internal mammary artery grafts may provide additional benefits. Bilateral internal mammary artery grafting can be safely performed in most patients (level II evidence). The late survival in patients with bilateral internal mammary artery grafts is favorable. However, there is as yet no completed randomized trial on this subject. Thus the lack of robust data makes previous reports amenable to criticism. This review examines published data on bilateral internal mammary artery revascularization spanning the last 15 years, and addresses the advantages and disadvantages of arterial conduits in coronary surgery.

Intra-aortic balloon pump (ΙΑΒΡ): from the old trends and studies to the current "extended" indications of its use.

This report outlines the well defined indications of using IABP and also favours extending the indications of IABP use, to include not only "therapeutically" the aging unstable patients but also "prophylactically" patients with low EF or high Euroscore.

Transthoracic intra-aortic balloon pump removal without repeat sternotomy.

Transaortic balloon catheter insertion for intra-aortic balloon assistance is a practical alternative to the standard transfemoral cannulation in patients with significant aortoiliac occlusive disease. We describe a technique whereby a transthoracic balloon is removed with the aid of video-assisted thoracoscopy.

Successful management of membrane oxygenator failure during cardiopulmonary bypass--the importance of safety algorithm and simulation drills.

With a high risk to time ratio, the advent of cardiopulmonary bypass has facilitated greater advances in technical procedures in cardiac surgery. This, however, has not come without its own complication risk and previous near misses have been reported with regard to various technical aspects of the cardiopulmonary bypass circuit. We present a case of a failed membrane oxygenator and discuss the real-life aspects to managing this complication without added risk to the patient.

Seronegative rheumatoid arthritis: a rare cause of effusive-constrictive pericarditis requiring pericardiectomy.

Effusive-constrictive pericarditis is a rare condition. In this report, we describe a case of effusive-constrictive pericarditis caused by seronegative rheumatoid arthritis which was successfully treated with surgical pericardiectomy.

Brief review on systematic hypothermia for the protection of central nervous system during aortic arch surgery: a double-sword tool?

Antegrade selective cerebral perfusion in conjunction with hypothermia attenuate postoperative neurological injury, which in turn still remains the main cause of mortality and morbidity following aortic arch surgery. Hypothermic circulatory arrest however could be a useful tool during arch surgery, surgery for chronic thromboembolic disease, air on the arterial line during CPB, during cavotomy for extraction of renal cell carcinoma with level IV extension, or when dealing with difficult trauma to the SVC or IVC. Cerebral protective effects with hypothermic procedures including inhibition of neuron excitation, and discharge of excitable amino acids, and thereby, prevention of an increase in intercellular calcium ions, hyperoxidation of lipids in cell membranes, and free radical production.The authors are briefly discussing the fundamental principles of using hypothermia as an adjunct tool of the cardiothoracic surgeon's practice. The relationship between temperature, flow, metabolic requirements and adverse effects is addressed.

Intra aortic balloon pump: literature review of risk factors related to complications of the intraaortic balloon pump.

The increasing use of the intra aortic balloon pump is attributed to the relatively easy percutaneous insertion and the low threshold of use over the past few years, especially in elderly patients with multi-vessel diseases and an affected ejection fraction.Unfortunately, the clinical assessment of the complications associated to the use of this supporting device, underestimates the frequency of such complications.This report has looked at the current literature and attempt to identify incremental risk factors related to the development of adverse effects during support with an intaaortic balloon pump.The paper concludes that in contrary to early reports, newer studies have shown that complications following intraaortic balloon pump treatment, is decreasing. Moreover the literature suggests that the thrombosis and infective complications are relevant to the duration of the pump treatment, while the ischemic problems of the limbs are mostly linked to the atherosclerotic status of the common femoral artery.

Risk analysis and outcome of mediastinal wound and deep mediastinal wound infections with specific emphasis to omental transposition.

BACKGROUND: To report our experience, with Deep mediastinal wound infections (DMWI). Emphasis was given to the management of deep infections with omental flaps METHODS: From February 2000 to October 2007, out of 3896 cardiac surgery patients (prospective data collection) 120 pts (3.02%) developed sternal wound infections. There were 104 males & 16 females; (73.7%) CABG, (13.5%) Valves & (9.32%) CABG and Valve. RESULTS: Superficial sternal wound infection detected in 68 patients (1.75%) and fifty-two patients (1.34%) developed DMWI. The incremental risk factors for development of DMWI were: Diabetes (OR = 3.62, CI = 1.2-10.98), Pre Op Creatinine > 200 µmol/l (OR = 3.33, CI = 1.14-9.7) and Prolong ventilation (OR = 4.16, CI = 1.73-9.98). Overall mortality for the DMWI was 9.3% and the specific mortality of the omental flap group was 8.3%. 19% of the "DMWI group", developed complications: hematoma 6%, partial flap loss 3.0%, wound dehiscence 5.3%. Mean Hospital Stay: 59 ± 21.5 days. CONCLUSION: Post cardiac surgery sternal wound complications remain challenging. The role of multidisciplinary approach is fundamental, as is the importance of an aggressive early wound exploration especially for deep sternal infections.