Transcatheter aortic valve implantation for high-risk patients with severe aortic stenosis: A systematic review

ObjectivesThe present systematic review objectively assessed the safety and clinical effectiveness of transcatheter aortic valve implantation for patients at high surgical risk with severe aortic stenosis.MethodsElectronic searches were performed in 6 databases from January 2000 to March 2009. The end points included feasibility, safety, efficacy, and durability. Clinical effectiveness was synthesized through a narrative review with full tabulation of results of all included studies.ResultsThe current evidence on transcatheter aortic valve implantation for aortic stenosis is limited to short-term observational studies. The overall procedural success rates ranged from 74% to 100%. The incidence of major adverse events included 30-day mortality (0%–25%), major ventricular tachyarrhythmia (0%–4%), myocardial infarction (0%–15%), cardiac tamponade (2%–10%), stroke (0%–10%), conversion to surgery (0%–8%), moderate to major paravalvular leak (4%–35%), vascular complication (8%–17%), valve-in-valve procedure (2%–12%), and aortic dissection/perforation (0%–4%). The overall 30-day major adverse cardiovascular and cerebral events ranged from 3% to 35%. The mean aortic valve area ranged from 0.5 to 0.8 cm2 before and 1.3 to 2.0 cm2 after transcatheter aortic valve implantation. The mean pressure gradient ranged from 34 to 58 mm Hg before and 3 to 12 mm Hg after transcatheter aortic valve implantation. There was no significant deterioration in echocardiography measurements during the assessment period. Death rate at 6 months postprocedure ranged from 18% to 48%. No studies had adequate follow-up to reliably evaluate long-term outcomes.ConclusionsThe procedure has a potential for serious complications. Although short-term efficacy based on echocardiography measurements is good, there is little evidence on long-term outcomes. The use of transcatheter aortic valve implantation should be considered only within the boundaries of clinical trials

Extrapleural pneumonectomy for malignant pleural mesothelioma: Outcomes of treatment and prognostic factors

ObjectiveThis study aimed to evaluate the perioperative and long-term outcomes associated with extrapleural pneumonectomy for patients with malignant pleural mesothelioma.MethodsFrom October 1994 to April 2008, 70 patients were selected for extrapleural pneumonectomy. Univariate analysis was performed using the Kaplan–Meier method and compared using the log-rank test. Multivariate analysis with entering and removing limits of P less than .10 and P greater than .05, respectively, was used. The prognostic factors included age, gender, side of disease, asbestos exposure, histology, positron emission tomography, date of surgery, neoadjuvant chemotherapy, completeness of cytoreduction, lymph node involvement, perioperative morbidity, adjuvant radiotherapy, and pemetrexed-based chemotherapy.ResultsThe mean age of patients was 55 years (standard deviation = 10). Fifty-eight patients had epithelial tumors. Six patients received neoadjuvant chemotherapy, 28 patients received adjuvant radiotherapy, and 16 patients received postoperative pemetrexed-based chemotherapy. Forty-four patients had no lymph node involvement. The perioperative morbidity and mortality were 37% and 5.7%, respectively. Complications included hemothorax (n = 7), atrial fibrillation (n = 6), empyema (n = 4), bronchopulmonary fistula (n = 3), right-sided heart failure (n = 2), pneumonia (n = 1), constrictive pericarditis (n = 1), acute pulmonary edema (n = 1), small bowel herniation (n = 1), and disseminated intravascular coagulopathy (n = 1). The median survival was 20 months, with a 3-year survival of 30%. Asbestos exposure, negative lymph node involvement, and receipt of adjuvant radiation or postoperative pemetrexed-based chemotherapy were associated with improved survival on both univariate and multivariate analyses.ConclusionThe present study supports the use of extrapleural pneumonectomy-based multimodal therapy in carefully selected patients with malignant pleural mesothelioma

Extracorporeal membrane oxygenation for very high-risk transcatheter aortic valve implantation

Background Transcatheter aortic valve implantation (TAVI) can cause profound haemodynamic perturbation in the peri-operative period. Veno-arterial extracorporeal membrane oxygenation (ECMO) can be used to provide cardiorespiratory support during this time, either prophylactically or emergently

The ARCH Projects: design and rationale (IAASSG 001)

OBJECTIVE A number of factors limit the effectiveness of current aortic arch studies in assessing optimal neuroprotection strategies, including insufficient patient numbers, heterogenous definitions of clinical variables, multiple technical strategies, inadequate reporting of surgical outcomes and a lack of collaborative effort. We have formed an international coalition of centres to provide more robust investigations into this topic. METHODS High-volume aortic arch centres were identified from the literature and contacted for recruitment. A Research Steering Committee of expert arch surgeons was convened to oversee the direction of the research. RESULTS The International Aortic Arch Surgery Study Group has been formed by 41 arch surgeons from 10 countries to better evaluate patient outcomes after aortic arch surgery. Several projects, including the establishment of a multi-institutional retrospective database, randomized controlled trials and a prospectively collected database, are currently underway. CONCLUSIONS Such a collaborative effort will herald a turning point in the surgical management of aortic arch pathologies and will provide better powered analyses to assess the impact of varying surgical techniques on mortality and morbidity, identify predictors for neurological and operative risk, formulate and validate risk predictor models and review long-term survival outcomes and quality-of-life after arch surger

Large expert-curated database for benchmarking document similarity detection in biomedical literature search

Document recommendation systems for locating relevant literature have mostly relied on methods developed a decade ago. This is largely due to the lack of a large offline gold-standard benchmark of relevant documents that cover a variety of research fields such that newly developed literature search techniques can be compared, improved and translated into practice. To overcome this bottleneck, we have established the RElevant LIterature SearcH consortium consisting of more than 1500 scientists from 84 countries, who have collectively annotated the relevance of over 180 000 PubMed-listed articles with regard to their respective seed (input) article/s. The majority of annotations were contributed by highly experienced, original authors of the seed articles. The collected data cover 76% of all unique PubMed Medical Subject Headings descriptors. No systematic biases were observed across different experience levels, research fields or time spent on annotations. More importantly, annotations of the same document pairs contributed by different scientists were highly concordant. We further show that the three representative baseline methods used to generate recommended articles for evaluation (Okapi Best Matching 25, Term Frequency–Inverse Document Frequency and PubMed Related Articles) had similar overall performances. Additionally, we found that these methods each tend to produce distinct collections of recommended articles, suggesting that a hybrid method may be required to completely capture all relevant articles. The established database server located at https://relishdb.ict.griffith.edu.au is freely available for the downloading of annotation data and the blind testing of new methods. We expect that this benchmark will be useful for stimulating the development of new powerful techniques for title and title/abstract-based search engines for relevant articles in biomedical research

Large expert-curated database for benchmarking document similarity detection in biomedical literature search

Document recommendation systems for locating relevant literature have mostly relied on methods developed a decade ago. This is largely due to the lack of a large offline gold-standard benchmark of relevant documents that cover a variety of research fields such that newly developed literature search techniques can be compared, improved and translated into practice. To overcome this bottleneck, we have established the RElevant LIterature SearcH consortium consisting of more than 1500 scientists from 84 countries, who have collectively annotated the relevance of over 180 000 PubMed-listed articles with regard to their respective seed (input) article/s. The majority of annotations were contributed by highly experienced, original authors of the seed articles. The collected data cover 76% of all unique PubMed Medical Subject Headings descriptors. No systematic biases were observed across different experience levels, research fields or time spent on annotations. More importantly, annotations of the same document pairs contributed by different scientists were highly concordant. We further show that the three representative baseline methods used to generate recommended articles for evaluation (Okapi Best Matching 25, Term Frequency-Inverse Document Frequency and PubMed Related Articles) had similar overall performances. Additionally, we found that these methods each tend to produce distinct collections of recommended articles, suggesting that a hybrid method may be required to completely capture all relevant articles. The established database server located at https://relishdb.ict.griffith.edu.au is freely available for the downloading of annotation data and the blind testing of new methods. We expect that this benchmark will be useful for stimulating the development of new powerful techniques for title and title/abstract-based search engines for relevant articles in biomedical research.Peer reviewe

A Triple Test for Behavioral Economics Models and Public Health Policy

We propose a triple test to evaluate the usefulness of behavioral economics models for public health policy. Test 1 is whether the model provides reasonably new insights. Test 2 is on whether these have been properly applied to policy settings. Test 3 is whether they are corroborated by evidence. Where a test is not passed, this may point to directions for needed further research. We exemplify by considering the cases of social interactions models, self-control models and, in relation to health message framing, prospect theory; out of these, only a correctly applied prospect theory fully passes the tests at present

The NeST (Neoadjuvant systemic therapy in breast cancer) study: National Practice Questionnaire of United Kingdom multi-disciplinary decision making

Abstract: Background: Neoadjuvant systemic therapy (NST) is increasingly used in the treatment of breast cancer, yet it is clear that there is significant geographical variation in its use in the UK. This study aimed to examine stated practice across UK breast units, in terms of indications for use, radiological monitoring, pathological reporting of treatment response, and post-treatment surgical management. Methods: Multidisciplinary teams (MDTs) from all UK breast units were invited to participate in the NeST study. A detailed questionnaire assessing current stated practice was distributed to all participating units in December 2017 and data collated securely usingREDCap. Descriptive statistics were calculated for each questionnaire item. Results: Thirty-nine MDTs from a diverse range of hospitals responded. All MDTs routinely offered neoadjuvant chemotherapy (NACT) to a median of 10% (range 5–60%) of patients. Neoadjuvant endocrine therapy (NET) was offered to a median of 4% (range 0–25%) of patients by 66% of MDTs. The principal indication given for use of neoadjuvant therapy was for surgical downstaging. There was no consensus on methods of radiological monitoring of response, and a wide variety of pathological reporting systems were used to assess tumour response. Twenty-five percent of centres reported resecting the original tumour footprint, irrespective of clinical/radiological response. Radiologically negative axillae at diagnosis routinely had post-NACT or post-NET sentinel lymph node biopsy (SLNB) in 73.0 and 84% of centres respectively, whereas 16% performed SLNB pre-NACT. Positive axillae at diagnosis would receive axillary node clearance at 60% of centres, regardless of response to NACT. Discussion: There is wide variation in the stated use of neoadjuvant systemic therapy across the UK, with general low usage of NET. Surgical downstaging remains the most common indication of the use of NAC, although not all centres leverage the benefits of NAC for de-escalating surgery to the breast and/or axilla. There is a need for agreed multidisciplinary guidance for optimising selection and management of patients for NST. These findings will be corroborated in phase II of the NeST study which is a national collaborative prospective audit of NST utilisation and clinical outcomes

A Meaningful U.S. Cap-and-Trade System to Address Climate Change

There is growing impetus for a domestic U.S. climate policy that can provide meaningful reductions in emissions of CO2 and other greenhouse gases. In this article, I propose and analyze a scientifically sound, economically rational, and politically feasible approach for the United States to reduce its contributions to the increase in atmospheric concentrations of greenhouse gases. The proposal features an up-stream, economy-wide CO2 cap-and-trade system which implements a gradual trajectory of emissions reductions over time, and includes mechanisms to reduce cost uncertainty. I compare the proposed system with frequently discussed alternatives. In addition, I describe common objections to a cap-and-trade approach to the problem, and provide responses to these objections

Bicuspid aortic valve disease – the influence of valve morphotype on age at and types of surgical treatment

Background: Patients with bicuspid aortic valve (BAV) with zero or two raphes have been under-represented in previous studies. Whether these patients have unique clinical courses remains unclear. We describe the indications for and types of surgery in patients with BAV, and describe differences between valve morphotypes. Methods: Adults who had undergone aortic and/or aortic valve surgery for BAV disease at our centres were identified and classified according to the Sievers definitions. Results: 317 patients were included (74.4% male, median age at surgery 62 years). Of these, 187 (59.0%) had aortic valve surgery, 7 (2.2%) aortic surgery, 120 (37.9%) combined valve and aortic surgery and 3 had a Ross procedure. Most patients had aortic stenosis (71.9%), followed by aortic regurgitation (16.7%). 30-day mortality was low (1.6%).The commonest valve morphology was type-1 (one raphe) in 89.6%; type-0 (no raphes) occurred in 7.9% and type-2 (two raphes) in 2.5%. Patients with type-2 valves were substantially younger at time of surgery than type-1 patients (median 36 vs 63 years, p = 0.008). A higher proportion of patients with type-0 valves required aortic surgery than those with type-1 (68.0% vs 37.3%, p = 0.007). There were no differences between groups for the indication for surgery, valvular abnormality or 30-day mortality. Conclusions: The number of BAV raphes was independently and significantly associated with age at surgery and the need for aortic intervention. Patients with type 0 and type 2 valves are a small but important proportion of the BAV population, potentially requiring different clinical surveillance and management