Therapeutic options for patients with chronic refractory angina pectoris

In Raman thermometry, several assumptions are made to model the heat conduction and to extract the thermal conductivity of the samples from the measured data. In this work, the heat conduction in bulk and mesa-like samples was investigated by numerical simulation and measured by the temperature-induced Raman shift method, to study the range of applicability of these assumptions. The effects of light penetration depth and finite sample size on the accuracy of the thermal conductivity determination were investigated by comparing the results of the finite element method with the usual analytical approximation for bulk samples. We found that the assumptions used in the analytical model can be applied to extract the thermal conductivity in solids if the following conditions are fulfilled: the ratio of light penetration depth to laser spot radius is smaller than 0.5, the ratio of spot radius to sample thickness is smaller than 0.1, and the ratio of spot radius to sample half width is smaller than 0.01.JJF and CMST acknowledge the Swedish Research Council VR (349-2007-8664 and 2014-5100) and the Linnaeus Center in Advanced Optics and Photonics for financial support. CMST and ECA acknowledge support from the Spanish MINECO and the Catalan AGAUR (FIS2015-70862-P and CSD2010-00044). JJF is especially grateful to Dr. M. Sledzinska and Dr. B Graczykowski for discussions and assistance with the Raman measurements and simulations. JJF thanks Profs. S. Anand and S. Lourdudoss, and Mr. A. Abedin, for providing the bulk and microcrystal samples. ICN2 acknowledges support from the Severo Ochoa Program (MINECO, Grant SEV-2013-0295) and funding from the CERCA Programme/Generalitat de Catalunya.Peer reviewe

Twelve tips for implementing a community of practice for faculty development

Teaching and learning practices often fail to incorporate new concepts in the ever-evolving field of medical education. Although medical education research provides new insights into curricular development, learners' engagement, assessment methods, professional development, interprofessional education, and so forth, faculty members often struggle to modernize their teaching practices. Communities of practice (CoP) for faculty development offer an effective and sustainable approach for knowledge management and implementation of best practices. A successful CoP creates and shares knowledge in the context of a specific practice toward the development of expertise. CoPs' collaborative nature, based on the co-creation of practical solutions to daily problems, aligns well with the goals of applying best practices in health professions education and training new faculty members. In our article, we share 12 tips for implementing a community of practice for faculty development. The tips were based on a comprehensive literature review and the authors' experiences

The Impact of Curriculum Design in the Acquisition of Knowledge of Oncology: Comparison Among Four Medical Schools

Over the past 5years, cancer has replaced coronary heart disease as the leading cause of death in the Netherlands. It is thus paramount that medical doctors acquire a knowledge of cancer, since most of them will face many patients with cancer. Studies, however, have indicated that there is a deficit in knowledge of oncology among medical students, which may be due not only to the content but also to the structure of the curriculum. In this study, we compared students' knowledge acquisition in four different undergraduate medical programs. Further, we investigated possible factors that might influence students' knowledge growth as related to oncology. The participants comprised 1440 medical students distributed over four universities in the Netherlands. To measure students' knowledge of oncology, we used their progress test results from 2007 to 2013. The progress test consists of 200 multiple-choice questions; this test is taken simultaneously four times a year by all students. All questions regarding oncology were selected. We first compared the growth of knowledge of oncology using mixed models. Then, we interviewed the oncology coordinator of each university to arrive at a better insight of each curriculum. Two schools showed similar patterns of knowledge growth, with a slight decrease in the growth rate for one of them in year 6. The third school had a faster initial growth with a faster decrease over time compared to other medical schools. The fourth school showed a steep decrease in knowledge growth during years 5 and 6. The interviews showed that the two higher-scoring schools had a more focused semester on oncology, whereas in the others, oncology was scattered throughout the curriculum. Furthermore, the absence of a pre-internship training program seemed to hinder knowledge growth in one school. Our findings suggest that curricula have an influence on students' knowledge acquisition. A focused semester on oncology and a pre-internship preparatory training program are likely to have a positive impact on students' progress in terms of knowledge of oncology

The Effects of Expert and Augmented Feedback on Learning a Complex Medical Skill

Many medical skills are complex due to their requirements for integration of declarative (biomedical) knowledge with perceptual–motor and perceptual–cognitive proficiency. While feedback generally helps learners guide their actions, it is unclear how feedback supports the integration of declarative knowledge with skills. Thus, we investigated the effect of expert and augmented feedback on acquisition and retention of a complex medical skill (acquiring a transthoracic echocardiogram) in a simulation study. We randomly assigned 36 medical undergraduate students to one of three feedback sources: Expert (EF), Augmented visual (HS), and Expert plus Help Screen (EF + HS). Participants practiced until reaching proficiency. Outcome measures (knowledge test and practical skill ratings on a 5-point scale), were gathered at initial acquisition and at retention after 11 days, the time needed to obtain the images and the quality of images obtained. We divided the knowledge test into three topics: names of the images, manipulation of the probe, and anatomy of the heart. At acquisition, immediately after training, EF group participants were faster at obtaining images than participants in the two other groups. On the retention test, there were no group differences for speed of obtaining images, but the EF + HS group scored significantly higher than the other two groups on image quality. Thus, expert feedback best assisted initial acquisition and combined augmented and expert feedback best assisted retention of this complex medical task. Expert assistance reduced learners’ cognitive load during initial practice, helping learners integrate declarative knowledge with physical skills

Cumulative assessment: does it improve students’ knowledge acquisition and retention? = Avaliação cumulativa: melhora a aquisição e a retenção do conhecimento pelos estudantes?

OBJETIVOS: A avaliação cumulativa tem sido usada como uma ferramenta para orientar o comportamento de estudo dos alunos, uma vez que aumenta o tempo de auto aprendizado, ao mesmo tempo que distribui o tempo de estudo de forma mais uniforme ao longo do curso. No entanto, pouco se sabe sobre o impacto da avaliação cumulativa na evolução do conhecimento dos estudantes. Portanto, nosso estudo comparou o aumento do conhecimento entre estudantes que participaram de um curso com avaliação cumulativa, e aqueles que tiveram avaliação de fim de curso. Nossa hipótese é que os estudantes na condição de avaliação cumulativa teriam um aumento maior no conhecimento em comparação com os estudantes na condição de avaliação do final do curso. MÉTODOS: Este é um estudo de acompanhamento de um experimento randomizado anterior, que comparou o desempenho entre estudantes que participaram de um curso com avaliação cumulativa e aqueles com avaliação de fim de curso. Nós reunimos dados dos primeiros quatro Testes do Progresso interuniversitários holandeses subsequentes ao experimento, em 62 estudantes. Destes, 37 estavam na condição de avaliação de final de curso e 25 estavam na condição de avaliação cumulativa. As questões foram classificadas como parte do bloco de ensino ou não. Para analisar o crescimento do conhecimento dos estudantes, conduzimos um Modelo Linear Geral. RESULTADOS: Nossos resultados demonstraram que houve um aumento significativo no conhecimento dos estudantes nos quatro Testes do Progresso subsequentes. Além disso, nosso modelo linear geral não mostrou diferença entre os dois grupos, indicando que a avaliação cumulativa e a avaliação no final do curso produziram resultados semelhantes ao comparar o crescimento do conhecimento dos alunos CONCLUSÕES: Até agora, pouca evidência apoiou o uso da avaliação cumulativa como uma ferramenta para aumentar o crescimento do conhecimento dos alunos. A falha em encontrar um efeito positivo da avaliação cumulativa na retenção de conhecimento pode ser explicada pelo caráter repetitivo do nosso currículo (em espiral

Investigation into cardiac sympathetic innervation during the commencement of haemodialysis in patients with chronic kidney disease

Background: Patients with chronic kidney disease (CKD) who undergo chronic haemodialysis (HD) show altered sympathetic tone, which is related to a higher cardiovascular mortality. The purpose of this study was to investigate the effect of transition from pre-HD to HD on cardiac sympathetic innervation. Methods: Eighteen patients aged 58 ± 18 years (mean ± standard deviation [SD]), 13 males and five females, with stage 5 CKD and nine healthy control subjects aged 52 ± 17 (mean ± SD), three males and six females, were included in this prospective study between May 2010 and December 2013. All patients underwent 123I-labelled meta-iodobenzylguanidine (123I-MIBG) scintigraphy for cardiac sympathetic innervation and electrocardiographically gated adenosine stress and rest 99mTc-labelled tetrofosmin single-photon emission computed tomography for myocardial perfusion imaging prior to (pre-HD) and 6 months after the start of HD. Results of 123I-MIBG scans in patients were compared to controls. Impaired cardiac sympathetic innervation was defined as late heart-to-mediastinum ratio (HMR) < 2.0. Results: Mean late HMR was lower in patients during HD (2.3) than in controls (2.9) (p = 0.035); however, in patients it did not differ between pre-HD and after the start of HD. During HD, two patients showed new sympathetic innervation abnormalities, and in three patients innervation abnormalities seemed to coincide with myocardial perfusion abnormalities. Conclusions: CKD patients show cardiac sympathetic innervation abnormalities, which do not seem to progress during the maintenance HD. The relationship between sympathetic innervation abnormalities and myocardial perfusion abnormalities in HD patients needs further exploration

PET and MRI for the evaluation of regional myocardial perfusion and wall thickening after myocardial infarction

Deterioration of left ventricular (LV) function after myocardial infarction (MI) is a major cause of heart failure. Myocardial perfusion performance may play an important role in deterioration or improvement in LV function after MI. The aim of this study was to evaluate the myocardial perfusion reserve (MPR) and stress perfusion in deteriorating and non-deteriorating LV segments in patients after MI by PET and MRI, respectively. Regional wall thickening of 352 segments in 22 patients was assessed at 4 and 24 months after MI by cardiac MRI. PET was performed to evaluate MPR and adenosine stress N-13-ammonia perfusion 24 months after MI. Segments were divided into four groups according to deterioration or improvement in wall thickening. Normal functional segments at 4 months after MI that remained stable had a significantly higher mean MPR and mean stress perfusion PET value than deteriorated segments (p < 0.001). Furthermore, dysfunctional segments that improved had a significantly higher mean stress perfusion PET value than dysfunctional segments that remained dysfunctional (p < 0.001). This study demonstrated the additional value of myocardial perfusion assessment in relation to the functional integrity of the injured myocardium. Segmental functional LV improvement after MI was associated with better regional myocardial perfusion characteristics. Furthermore, the amount of wall thickening reduction was associated with regional myocardial perfusion abnormalities in patients after MI

Measurement of coronary calcium scores or exercise testing as initial screening tool in asymptomatic subjects with ST-T changes on the resting ECG:An evaluation study

Background: Asymptomatic subjects at intermediate coronary risk may need diagnostic testing for risk stratification. Both measurement of coronary calcium scores and exercise testing are well established tests for this purpose. However, it is not clear which test should be preferred as initial diagnostic test. We evaluated the prevalence of documented coronary artery disease (CAD) according to calcium scores and exercise test results. Methods: Asymptomatic subjects with ST-T changes on a rest ECG were selected from the population based PREVEND cohort study and underwent measurement of calcium scores by electron beam tomography and exercise testing. With calcium scores ≥10 or a positive exercise test, myocardial perfusion imaging (MPS) or coronary angiography (CAG) was recommended. The primary endpoint was documented obstructive CAD (≥50% stenosis). Results: Of 153 subjects included, 149 subjects completed the study protocol. Calcium scores ≥400, 100-399, 10-99 and &lt;10 were found in 16, 29, 18 and 86 subjects and the primary endpoint was present in 11 (69%), 12 (41%), 0 (0%) and 1 (1%) subjects, respectively. A positive, nondiagnostic and negative exercise test was present in 33, 27 and 89 subjects and the primary endpoint was present in 13 (39%), 5 (19%) and 6 (7%) subjects, respectively. Receiver operator characteristics analysis showed that the area under the curve, as measure of diagnostic yield, of 0.91 (95% CI 0.84-0.97) for calcium scores was superior to 0.74 (95% CI 0.64-0.83) for exercise testing (p = 0.004). Conclusion: Measurement of coronary calcium scores is an appropriate initial non-invasive test in asymptomatic subjects at increased coronary risk.</p

Measurement of coronary calcium scores or exercise testing as initial screening tool in asymptomatic subjects with ST-T changes on the resting ECG:An evaluation study

Background: Asymptomatic subjects at intermediate coronary risk may need diagnostic testing for risk stratification. Both measurement of coronary calcium scores and exercise testing are well established tests for this purpose. However, it is not clear which test should be preferred as initial diagnostic test. We evaluated the prevalence of documented coronary artery disease (CAD) according to calcium scores and exercise test results. Methods: Asymptomatic subjects with ST-T changes on a rest ECG were selected from the population based PREVEND cohort study and underwent measurement of calcium scores by electron beam tomography and exercise testing. With calcium scores ≥10 or a positive exercise test, myocardial perfusion imaging (MPS) or coronary angiography (CAG) was recommended. The primary endpoint was documented obstructive CAD (≥50% stenosis). Results: Of 153 subjects included, 149 subjects completed the study protocol. Calcium scores ≥400, 100-399, 10-99 and &lt;10 were found in 16, 29, 18 and 86 subjects and the primary endpoint was present in 11 (69%), 12 (41%), 0 (0%) and 1 (1%) subjects, respectively. A positive, nondiagnostic and negative exercise test was present in 33, 27 and 89 subjects and the primary endpoint was present in 13 (39%), 5 (19%) and 6 (7%) subjects, respectively. Receiver operator characteristics analysis showed that the area under the curve, as measure of diagnostic yield, of 0.91 (95% CI 0.84-0.97) for calcium scores was superior to 0.74 (95% CI 0.64-0.83) for exercise testing (p = 0.004). Conclusion: Measurement of coronary calcium scores is an appropriate initial non-invasive test in asymptomatic subjects at increased coronary risk.</p