Surgical Strategies in Reoperation of the Proximal Aorta and Arch for Patients with Previous Frozen Elephant Trunk.

Background: The frozen elephant trunk (FET) technique is increasingly utilized for aortic arch replacement in cases of aortic dissections and aneurysms. This rise in usage has led to more patients needing redo aortic surgeries due to progression of existing conditions, FET-related complications, or new valvular/coronary diseases. This article aims to evaluate surgical techniques to minimize risks during these reoperations, including a case study of a complex redo surgery. Methods: A comprehensive examination of surgical strategies was conducted, focusing on preoperative preparation, cannulation site identification, cerebral and cardiac protective measures, and pitfalls to avoid. The importance of adapting to the modified anatomical landscape post-FET is emphasized. A detailed case study of a patient undergoing complex redo FET surgery is included. Results: The article identified key surgical strategies for reoperation in patients with prior FET, highlighting the importance of meticulous preoperative planning and execution. Techniques to minimize risks include detailed imaging for planning, strategic cannulation for optimal perfusion, multidisciplinary approaches as well as careful fail-safe measures. The case study demonstrates the practical application of these strategies in a high-risk scenario. The evidence underscores the necessity for individualized patient management and the development of standardized protocols. Conclusions: The FET technique, while effective for initial aortic arch repairs, often necessitates complex reoperations. Adopting advanced surgical strategies and multidisciplinary planning can significantly mitigate risks associated with these procedures. Future research should focus on refining these techniques and establishing standardized protocols to improve patient outcomes.

Assessment of Myocardial Viability in Ischemic Cardiomyopathy With Reduced Left Ventricular Function Undergoing Coronary Artery Bypass Grafting.

BACKGROUND: We aim to provide a comprehensive review of the current state of knowledge of myocardial viability assessment in patients undergoing coronary artery bypass grafting (CABG), with a focus on the clinical markers of viability for each imaging modality. We also compare mortality between patients with viable myocardium and those without viability who undergo CABG. METHODS: A systematic database search with meta-analysis was conducted of comparative original articles (both observations and randomized controlled studies) of patients undergoing CABG with either viable or nonviable myocardium, in EMBASE, MEDLINE, Cochrane database, and Google Scholar, from inception to 2022. Imaging modalities included were dobutamine stress echocardiography (DSE), cardiac magnetic resonance (CMR), single-photon emission computed tomography (SPECT), and positron emission tomography (PET). RESULTS: A total of 17 studies incorporating a total of 2317 patients were included. Across all imaging modalities, the relative risk of death post-CABG was reduced in patients with versus without viability (random-effects model: odds ratio: 0.42; 95% confidence interval: 0.29-0.61; p < 0.001). Imaging for myocardial viability has significant clinical implications as it can affect the accuracy of the diagnosis, guide treatment decisions, and predict patient outcomes. Generally, based on local availability and expertise, either SPECT or DSE should be considered as the first step in evaluating viability, while PET or CMR would provide further evaluation of transmurality, perfusion metabolism, and extent of scar tissue. CONCLUSION: The assessment of myocardial viability is an essential component of preoperative evaluation in patients with ischemic heart disease undergoing surgical revascularization. Careful patient selection and individualized assessment of viability remain paramount.

Sarcopenia in colorectal cancer is related to socio-economic deprivation and Body Mass Index alone misrepresents underlying muscle loss in the deprived.

BACKGROUND & AIMS: Patients with colorectal cancer who are more socio-economically deprived have worse outcomes; deprivation is also associated with higher obesity rates, defined as a body mass index (BMI) of greater than thirty. Body composition (BC) factors such as sarcopenia and myosteatosis are also known to predispose to poorer outcomes following colorectal cancer surgery. There is limited evidence to date to relate the effect of deprivation upon these host characteristics that are linked to prognosis. We aimed to examine the relationship between deprivation and body composition in colorectal cancer. METHODS: Analysis was performed on a prospectively collected database of preoperative primary colorectal cancer patients at St Mark's - The National Bowel Hospital, UK. Body composition characteristics were identified by analysing the L3 axial slices of Computer Tomogram (CT) slices of preoperative staging using Slice-O-Matic software with Automatic Body composition Analyser using Computed tomography image Segmentation (ABACS) L3 plug-in. Deprivation status for each patient was determined using their postal code which was linked to the Index of Multiple Deprivation (IMD). Each domain of the IMD was examined individually in relation to BC characteristics. Binary logistic regression analysis was performed on the data using a model developed from previous published analyses of this dataset. RESULTS: Four hundred and nineteen patients were included in the final analysis, the median age was 69 years and 57% of the patient population was male. Patients who were more deprived were significantly more likely to be sarcopenic [OR 1.56 (95% CI 1.01-2.41, p = 0.045)] and myosteatotic [OR 1.69 (95% CI 1.019-2.81, p = 0.042)]. More deprived patients were also more likely to have a lower BMI [OR 0.60 (95% CI 0.38-0.94, p = 0.026)] despite no significant difference in visceral obesity between the most and least deprived. CONCLUSIONS: Deprivation is an important independent determinant of sarcopenia in the colorectal cancer population. Identifying these patients early and addressing reversible factors may help improve post-operative surgical outcomes in this poor prognostic group. Sarcopenia may be a premorbid state in the deprived colorectal cancer patient that may not be wholly driven by tumour characteristics.

Sarcopenia is independently associated with poor preoperative physical fitness in patients undergoing colorectal cancer surgery.

BACKGROUND: Accurate preoperative risk assessment for major colorectal cancer (CRC) surgery remains challenging. Body composition (BC) and cardiopulmonary exercise testing (CPET) can be used to evaluate risk. The relationship between BC and CPET in patients undergoing curative CRC surgery is unclear. METHODS: Consecutive patients undergoing CPET prior to CRC surgery between 2010 and 2020 were identified between two different UK hospitals. Body composition phenotypes such as sarcopenia, myosteatosis, and visceral obesity were defined using widely accepted thresholds using preoperative single axial slice CT image at L3 vertebrae. Relationships between clinicopathological, BC, and CPET variables were investigated using linear regression analysis. RESULTS: Two hundred eighteen patients with stage I-III CRC were included. The prevalence of sarcopenia, myosteatosis, and visceral obesity was 62%, 33%, and 64%, respectively. The median oxygen uptake at anaerobic threshold (VO2 at AT) was 12.2 mL/kg/min (IQR 10.6-14.2), and oxygen uptake at peak exercise (VO2 peak) was 18.8 mL/kg/min (IQR 15.4-23). On univariate linear regression analysis, male sex (P < 0.001) was positively associated with VO2 at AT. While ASA grade (P < 0.001) and BMI (P = 0.007) were negatively associated with VO2 at AT, on multivariate linear regression analysis, these variables remained significant (P < 0.05). On univariate linear regression analysis, male sex (P < 0.001) was positively associated with VO2 peak, whereas age (P < 0.001), ASA grade (P < 0.001), BMI (P = 0.003), sarcopenia (P = 0.015), and myosteatosis (P < 0.001) were negatively associated with VO2 peak. On multivariate linear regression analysis age (P < 0.001), ASA grade (P < 0.001), BMI (P < 0.001), and sarcopenia (P = 0.006) were independently and negatively associated with VO2 peak. CONCLUSIONS: The novel finding that sarcopenia is independently associated with reduced VO2 peak performance in CPET supports the supposition that reduced muscle mass relates to poor physical function in CRC patients. Further work should be undertaken to assess whether sarcopenia diagnosed on CT can act as suitable surrogate for CPET to further enhance personalized risk stratification.

Surgical Therapy of Infective Prosthesis Endocarditis following TAVI: A Single Center's Experience.

BACKGROUND/OBJECTIVES: Infective prosthesis endocarditis (IE) following transcatheter aortic valve implantation (TAVI) presents significant management challenges, marked by high mortality rates. This study reviews our center's experience with surgical interventions for IE in patients post-TAVI, focusing on outcomes, challenges, and procedural complexities, and providing an overview of the limited literature surrounding this subject. METHODS: This study was executed as a comprehensive retrospective analysis, targeting the clinical outcomes of surgical treatment in patients presenting with PVE following TAVI procedures at our institution. From July 2017 to July 2022, we identified five patients who had previously undergone transfemoral transcatheter aortic valve implantation and were later diagnosed with PVE needing surgery, strictly adhering to the modified Duke criteria. RESULTS: All surgical procedures were reported successful with no intra- or postoperative mortality. Patients were predominantly male (80%), with an average age of 76 ± 8.6 years, presenting mostly with dyspnea (NYHA Class II). The mean follow-up was between 121 and 1973 days, with outcomes showing no occurrences of stroke, myocardial infarction, or major bleeding. One patient expired from unrelated causes 3.7 years post-surgery. The operative and postoperative protocols demonstrated effective disease management with enhanced survival and minimal complications. CONCLUSIONS: The surgical treatment of IE following TAVI, though challenging, can be successfully achieved with careful patient selection and a multidisciplinary approach. The favorable outcomes suggest that surgical intervention remains a viable option for managing this high-risk patient group. Our study also highlights the scarce literature available on this topic, suggesting an urgent need for more comprehensive research to enhance understanding and improve treatment strategies. Future studies with larger cohorts are needed to further validate these findings and refine surgical strategies for this growing patient population.

Contemporary Use of Sodium Glucose Co-Transporter 2 Inhibitors in Hospitalized Heart Failure Patients: A "Real-World" Experience.

Background/Objectives: The aim of this study was to examine the association between in-hospital initiation of sodium glucose co-transporter 2 inhibitors (SGLT2is) and outcomes in hospitalized heart failure (HHF) patients utilizing data from a Greek center. Methods: The present work was a single-center, retrospective, observational study of consecutive HF patients hospitalized in a tertiary center. The study endpoint was all-cause mortality or HF rehospitalization. Univariate and multivariate Cox proportional-hazard models were conducted to investigate the association between SGLT2i administration at discharge and the study endpoint. Results: Sample consisted of 171 patients, 55 of whom (32.2%) received SGLT2is at discharge. Overall, mean follow-up period was 6.1 months (SD = 4.8 months). Patients who received SGLT2is at discharge had a 43% lower probability of the study endpoint compared to those who did not receive SGLT2is at discharge (HR = 0.57; 95% CI: 0.36-0.91; p = 0.018). After adjusting for age, gender, smoking, hemoglobin (Hgb), use of SGLT2is at admission, use of Angiotensin-Converting Enzyme Inhibitors (ACEI-Is)/Angiotensin Receptor Blockers (ARBs) at discharge and Sacubitril/Valsartan at discharge, the aforementioned result remained significant (HR = 0.38; 95% CI: 0.19-0.73; p = 0.004). The 55 patients who received SGLT2is at discharge were propensity score matched with the 116 patients who did not receive SGLT2is at discharge. Receiving SGLT2is at discharge continued to be significantly associated with a lower probability of the study endpoint (HR= 0.43; 95% CI: 0.20-0.89; p = 0.024). Conclusions: Initiation of SGLT2is in HHF patients may be associated with better outcomes.

Quality of life outcomes comparing primary Transoral Robotic Surgery (TORS) with primary radiotherapy for early-stage oropharyngeal squamous cell carcinoma: A systematic review and meta-analysis.

BACKGROUND: Transoral Robotic Surgery (TORS) and radiotherapy are considered oncologically equivalent primary treatment options for early-stage HPV-positive oropharyngeal squamous cell carcinoma (OPSCC). Quality of Life (QoL) and Patient Reported Outcome Measures (PROMs) are therefore imperative in supporting clinical decision-making and optimising patient-centred care. The aim of this article is to evaluate how these primary treatment modalities compare in terms of QoL. MATERIALS AND METHODS: Systematic review and meta-analysis of studies comparing primary TORS and primary radiotherapy for OPSCC using validated QoL tools. Swallowing and global QoL were the primary endpoints with secondary endpoints including all other QoL domains. An inverse variance random-effects model was employed to calculate the weighted estimate of the treatment effects across trials. RESULTS: A total of six studies collectively reporting on 555 patients were included (n = 236 TORS and n = 319 radiotherapy). Meta-analysis showed no significant difference for swallowing (mean difference = -0.24, p = 0.89) and global QoL (mean difference = 4.55, p = 0.14). For the remaining QoL domains (neck/shoulder impairment, neurotoxicity, voice, xerostomia, speech, and distress), the scarcity of data did not permit meta-analysis. However, the existing data showed no significant difference for any except for xerostomia where TORS appears favourable in the sole study reporting on this. CONCLUSIONS: TORS and radiotherapy appear to be comparable primary treatment options for early stage OPSCC when it comes to QoL. However, a substantial proportion of patients in the TORS group received adjuvant (chemo)radiotherapy rendering it difficult to establish the 'true' QoL outcomes following surgery alone. There are also minimal studies reporting QoL outcomes beyond swallowing and global QoL. Further research is therefore needed, including more randomised trials adequately powered to detect differences in QoL outcomes.

Feasibility study of rehabilitation for cardiac patients aided by an artificial intelligence web-based programme: a randomised controlled trial (RECAP trial)-a study protocol.

INTRODUCTION: Cardiac rehabilitation (CR) delivered by rehabilitation specialists in a healthcare setting is effective in improving functional capacity and reducing readmission rates after cardiac surgery. It is also associated with a reduction in cardiac mortality and recurrent myocardial infarction. This trial assesses the feasibility of a home-based CR programme delivered using a mobile application (app). METHODS: The Rehabilitation through Exercise prescription for Cardiac patients using an Artificial intelligence web-based Programme (RECAP) randomised controlled feasibility trial is a single-centre prospective study, in which patients will be allocated on a 1:1 ratio to a home-based CR programme delivered using a mobile app with accelerometers or standard hospital-based rehabilitation classes. The home-based CR programme will employ artificial intelligence to prescribe exercise goals to the participants on a weekly basis. The trial will recruit 70 patients in total. The primary objectives are to evaluate participant recruitment and dropout rates, assess the feasibility of randomisation, determine acceptability to participants and staff, assess the rates of potential outcome measures and determine hospital resource allocation to inform the design of a larger randomised controlled trial for clinical efficacy and health economic evaluation. Secondary objectives include evaluation of health-related quality of life and 6 minute walk distance. ETHICS AND DISSEMINATION: RECAP trial received a favourable outcome from the Berkshire research ethics committee in September 2022 (IRAS 315483).Trial results will be made available through publication in peer-reviewed journals and presented at relevant scientific meetings. TRIAL REGISTRATION NUMBER: ISRCTN97352737.

Valve Type and Operative Risks in Surgical Explantation of Transcatheter Aortic Valves: A Systematic Review and Meta-Analysis.

Indication to perform surgical explantation of TAVR is becoming increasingly more frequent, due to the higher number of transcatheter procedures performed in patients with longer life expectancy. We proposed to perform a systematic review and meta-analysis with metaregression to identify potential factors that can determine an increase in the high mortality and morbidity that characterize these surgical procedures. MEDLINE and Embase were searched for relevant studies. Twelve studies were eligible according to our inclusion criteria. TAVR explantation was confirmed as a procedure with high 30-day mortality (0.17; 95% CI, 0.14-0.21) and morbidity (stroke incidence 5%; 95% CI, 0.04-0.07; kidney injury incidence 16%; 95% CI, 0.11-0.24). The type of transcatheter valve implanted during the index procedure did not influence the outcomes after surgical explantation. The role of these high-risk operations is growing, and it will likely expand in the coming years. Specific tools for risk stratification are required.

Validation of Perioperative Troponin Levels for Predicting Postoperative Mortality and Long-Term Survival in Patients Undergoing Surgery for Hepatobiliary and Pancreatic Cancer.

Background: Hepatopancreato and biliary (HPB) tumors represent some of the leading cancer-related causes of death worldwide, with the majority of patients undergoing surgery in the context of a multimodal treatment strategy. Consequently, the implementation of an accurate risk stratification tool is crucial to facilitate informed consent, along with clinical decision making, and to compare surgical outcomes among different healthcare providers for either service evaluation or clinical audit. Perioperative troponin levels have been proposed as a feasible and easy-to-use tool in order to evaluate the risk of postoperative myocardial injury and 30-day mortality. The purpose of the present study is to validate the perioperative troponin levels as a prognostic factor regarding postoperative myocardial injury and 30-day mortality in Greek adult patients undergoing HPB surgery. Method: In total, 195 patients undergoing surgery performed by a single surgical team in a single tertiary hospital (2020-2022) were included. Perioperative levels of troponin before surgery and at 24 and 48 h postoperatively were assessed. Model accuracy was assessed by observed-to-expected (O:E) ratios, and area under the receiver operating characteristic curve (AUC). Survival at one year postoperatively was compared between patients with high and normal TnT levels at 24 h postoperatively. Results: Thirteen patients (6.6%) died within 30 days of surgery. TnT levels at 24 h postoperatively were associated with excellent discrimination and provided the best-performing calibration. Patients with normal TnT levels at 24 h postoperatively were associated with higher long-term survival compared to those with high TnT levels. Conclusions: TnT at 24 h postoperatively is an efficient risk assessment tool that should be implemented in the perioperative pathway of patients undergoing surgery for HPB cancer.

The Surgical Treatment of Infective Endocarditis: A Comprehensive Review.

Infective endocarditis (IE) is a severe cardiac complication with high mortality rates, especially when surgical intervention is delayed or absent. This review addresses the expanding role of surgery in managing IE, focusing on the variation in surgical treatment rates, the impact of patient demographics, and the effectiveness of different surgical approaches. Despite varying global data, a notable increase in surgical interventions for IE is evident, with over 50% of patients undergoing surgery in tertiary centres. This review synthesizes information from focused literature searches up to July 2023, covering preoperative to postoperative considerations and surgical strategies for IE. Key preoperative concerns include accurate diagnosis, appropriate antimicrobial treatment, and the timing of surgery, which is particularly crucial for patients with heart failure or at risk of embolism. Surgical approaches vary based on valve involvement, with mitral valve repair showing promising outcomes compared to replacement. Aortic valve surgery, traditionally favouring replacement, now includes repair as a viable option. Emerging techniques such as sutureless valves and aortic homografts are explored, highlighting their potential advantages in specific IE cases. The review also delves into high-risk groups like intravenous drug users and the elderly, emphasizing the need for tailored surgical strategies. With an increasing number of patients presenting with prosthetic valve endocarditis and device-related IE, the review underscores the importance of comprehensive management strategies encompassing surgical and medical interventions. Overall, this review provides a comprehensive overview of current evidence in the surgical management of IE, highlighting the necessity of a multidisciplinary approach and ongoing research to optimize patient outcomes.

Heart Transplantation.

Heart transplantation (HTx) remains the last therapeutic resort for patients with advanced heart failure. The present work is a clinically focused review discussing current issues in heart transplantation. Several factors have been associated with the outcome of HTx, such as ABO and HLA compatibility, graft size, ischemic time, age, infections, and the cause of death, as well as imaging and laboratory tests. In 2018, UNOS changed the organ allocation policy for HTx. The aim of this change was to prioritize patients with a more severe clinical condition resulting in a reduction in mortality of people on the waiting list. Advanced heart failure and resistant angina are among the main indications of HTx, whereas active infection, peripheral vascular disease, malignancies, and increased body mass index (BMI) are important contraindications. The main complications of HTx include graft rejection, graft angiopathy, primary graft failure, infection, neoplasms, and retransplantation. Recent advances in the field of HTx include the first two porcine-to-human xenotransplantations, the inclusion of hepatitis C donors, donation after circulatory death, novel monitoring for acute cellular rejection and antibody-mediated rejection, and advances in donor heart preservation and transportation. Lastly, novel immunosuppression therapies such as daratumumab, belatacept, IL 6 directed therapy, and IgG endopeptidase have shown promising results.

Artificial Intelligence in Heart Failure: Friend or Foe?

In recent times, there have been notable changes in cardiovascular medicine, propelled by the swift advancements in artificial intelligence (AI). The present work provides an overview of the current applications and challenges of AI in the field of heart failure. It emphasizes the "garbage in, garbage out" issue, where AI systems can produce inaccurate results with skewed data. The discussion covers issues in heart failure diagnostic algorithms, particularly discrepancies between existing models. Concerns about the reliance on the left ventricular ejection fraction (LVEF) for classification and treatment are highlighted, showcasing differences in current scientific perceptions. This review also delves into challenges in implementing AI, including variable considerations and biases in training data. It underscores the limitations of current AI models in real-world scenarios and the difficulty in interpreting their predictions, contributing to limited physician trust in AI-based models. The overarching suggestion is that AI can be a valuable tool in clinicians' hands for treating heart failure patients, as far as existing medical inaccuracies have been addressed before integrating AI into these frameworks.

The sympathetic nervous system in heart failure revisited.

Several attempts have been made, by the scientific community, to develop a unifying hypothesis that explains the clinical syndrome of heart failure (HF). The currently widely accepted neurohormonal model has substituted the cardiorenal and the cardiocirculatory models, which focused on salt-water retention and low cardiac output/peripheral vasoconstriction, respectively. According to the neurohormonal model, HF with eccentric left ventricular (LV) hypertrophy (LVH) (systolic HF or HF with reduced LV ejection fraction [LVEF] or HFrEF) develops and progresses because endogenous neurohormonal systems, predominantly the sympathetic nervous system (SNS) and the renin-angiotensin-aldosterone system (RAAS), exhibit prolonged activation following the initial heart injury exerting deleterious hemodynamic and direct nonhemodynamic cardiovascular effects. However, there is evidence to suggest that SNS overactivity often preexists HF development due to its association with HF risk factors, is also present in HF with preserved LVEF (diastolic HF or HFpEF), and that it is linked to immune/inflammatory factors. Furthermore, SNS activity in HF may be augmented by coexisting noncardiac morbidities and modified by genetic factors and demographics. The purpose of this paper is to provide a contemporary overview of the complex associations between SNS overactivity and the development and progression of HF, summarize the underlying mechanisms, and discuss the clinical implications as they relate to therapeutic interventions mitigating SNS overactivity.

Transcriptomic Analysis of Tight Junction Proteins Demonstrates the Aberrant Expression and Function of Zona Occludens 2 (ZO-2) Protein in Stanford Type A Aortic Dissection.

OBJECTIVE: Thoracic aortic aneurysm dissection (TAAD) represents a cardiac surgery emergency characterized by the disrupted integrity of the aortic wall and is associated with poor prognosis. In this context, the identification of biomarkers implicated in the pathobiology of TAAD is crucial. Our aim in the present original in silico study is to assess the differential gene expression profile of the tight junction proteins (TJPs) in patients with TAAD and to propose novel biomarkers for the diagnosis and prognosis of this disease. METHODS: We implemented bioinformatics methodology in order to construct the gene network of the TJPs family, identify the differentially expressed genes (DEGs) in pathologic aortic tissue excised from patients with TAAD as compared to healthy aortic tissue, and assess the related biological functions and the associated miRNA families. RESULTS: Data regarding the transcriptomic profile of selected genes were retrieved and incorporated from three microarray datasets, including 23 TAAD and 20 healthy control samples. A total of 32 TJPs were assessed. The zona occludens 2 (ZO-2) protein encoded by the gene TJP2 was significantly under-expressed in patients with TAAD compared to the control group (p = 0.009). ZO-2 was associated with fair discrimination and calibration traits in predicting the TAAD presentation. CpG islands of ZO-2 were demonstrated. No important difference was found regarding ZO-2 expression between aneurysmal non-dissected and healthy control aortic tissue. Finally, we performed gene set enrichment analysis (GSEA) and uncovered the major biological functions and miRNA families (hsa-miR-155-5p, hsa-miR-1-3p, hsa-miR-2118-5p, hsa-miR-4691-3p, and hsa-miR-1229-3p) relevant to ZO-2. CONCLUSIONS: These outcomes demonstrated the important role of ZO-2 in the pathobiology of TAAD.

Pneumomediastinum: Experience with 87 Patients.

OBJECTIVE: The aim of the present series was first to present our experience in the management of 37 patients with spontaneous pneumomediastinum (SPM), and further to indicate the necessity of identifying true SPM cases as they are currently inadequately defined. METHODS: This is a single-center, retrospective study, conducted in a university hospital. Consecutive adult patients with pneumomediastinum (PM) between January 2009 and March 2020 were involved in the series. The data about age, gender, symptoms, signs, treatment, length of hospital stay (LOS), and in-hospital mortality were evaluated. RESULTS: In total, 87 cases with pneumomediastinum (37 with spontaneous and 50 with secondary PM) were analyzed. Patients in both groups were of similar ages (P=0.4). Sufferers with secondary PM were more likely to have: an associated pneumothorax (19% vs 58%, P<0.05), a chest tube placed (18.9% vs 58%, P<0.05), an associated pleural effusion (0% vs 18%, P<0.05). They presented with a longer LOS (3.9 vs 5.3 days, P<0.05), and were more likely to die (0% vs 10%, P<0.05). Additionally they showed a higher prevalence of radiologic subcutaneous emphysema (49% vs 74%, P<0.05). CONCLUSION: Spontaneous pneumomediastinum is an onset of clinical importance with a low mortality rate, short LOS and good longterm prognosis. It often presents with chest pain, dyspnea and/or subcutaneous emphysema. However, secondary causes of mediastinal air must be ruled out, due to their potential devastating outcome if not diagnosed promptly. A consensus aimed at an update of the classification guidelines is more than indispensable.

Sizing the Frozen Elephant Trunk Based on Aortic Pathology and the Importance of Pre-Operative Imaging.

The frozen elephant trunk is a formidable tool for the aortovascular surgeon. An appreciation of how to size the graft in different pathologies is key in achieving optimal results. Herein, we demonstrate worked examples of how imaging can be used to plan for a frozen elephant trunk and discuss the nuisances and uncertainties of sizing using three index cases: Type A aortic dissection, distal thoracic aortic aneurysm and chronic dissection.

The Sympathetic Nervous System in Hypertensive Heart Failure with Preserved LVEF.

The neurohormonal model of heart failure (HF) pathogenesis states that a reduction in cardiac output caused by cardiac injury results in sympathetic nervous system (SNS) activation, that is adaptive in the short-term and maladaptive in the long-term. This model has proved extremely valid and has been applied in HF with a reduced left ventricular (LV) ejection fraction (LVEF). In contrast, it has been undermined in HF with preserved LVEF (HFpEF), which is due to hypertension (HTN) in the vast majority of the cases. Erroneously, HTN, which is the leading cause of cardiovascular disease and premature death worldwide and is present in more than 90% of HF patients, is tightly linked with SNS overactivity. In this paper we provide a contemporary overview of the contribution of SNS overactivity to the development and progression of hypertensive HF (HHF) as well as the clinical implications resulting from therapeutic interventions modifying SNS activity. Throughout the manuscript the terms HHF with preserved LVEF and HfpEF will be used interchangeably, considering that the findings in most HFpEF studies are driven by HTN.