Platelet reactivity is associated with pump thrombosis in patients with left ventricular assist devices.

Background: Patients with left ventricular assist devices (LVADs) are treated with a potent antithrombotic regimen to prevent pump thrombosis and thromboembolism. High on-treatment residual platelet reactivity (HRPR) is associated with ischemic outcomes in cardiovascular disease. Objectives: In the current study, we investigated the prevalence and clinical impact of HRPR in stable LVAD patients. Methods: Pump thrombosis, bleeding events, and death were assessed in 62 LVAD patients (19 HeartWare HVAD [Medtronic] and 43 HeartMate 3 [Abbott]) during a 2-year follow-up. Platelet aggregation was measured by multiple electrode aggregometry, and HRPR was defined as arachidonic acid (AA)-inducible platelet aggregation of ≥21 aggregation units. Soluble P-selectin was determined by enzyme-linked immunosorbent assay. Results: Three patients (4.8%) had pump thrombosis and 10 patients (16.1%) suffered a bleeding complication. AA-inducible platelet aggregation was significantly higher in patients with pump thrombosis (P = .01), whereas platelet aggregation in response to adenosine diphosphate (ADP) and thrombin receptor-activating peptide (TRAP) was comparable between patients without and those with pump thrombosis (both P > .05). Platelet aggregation in response to AA, ADP, and TRAP was similar in patients without and with a bleeding event (all P > .05). HRPR was detected in 29 patients (46.8%) and was associated with significantly higher platelet aggregation in response to AA, ADP, and TRAP as well as higher levels of soluble P-selectin compared with patients without HRPR (all P < .05). All pump thromboses occurred in patients with HRPR (3 vs 0; P = .06) and HVAD. Conclusion: Platelet reactivity is associated with pump thrombosis in LVAD patients. HRPR may represent a risk marker for pump thrombosis, particularly in HVAD patients.

Case-based blended eLearning scenarios-adequate for competence development or more?

BACKGROUND: Learning, competence development and scientific thinking in medicine need several strategies to facilitate new diagnostic and therapeutic ways. The optimal collaboration between creative thinking and biomedical informatics provides innovation for the individual patient and for a medical school or society. Utilizing the flexibilities of an e­learning platform, a case based blended learning (CBBL) framework consisting of A) case based textbook material, B) online e­CBL with question driven learning scenarios and C) simulated patient (SP) contact seminars was developed and implemented in multiple medical fields. Real-life clinical cases were anonymized and transferred into an interactive and an interdisciplinary eLearning platform. METHODS: As an example of the offered clinical teaching-case collection, an example of a psychiatric case for the disease "posttraumatic stress disorder (PTSD)" is presented: a 30-year-old man with a history of insomnia with difficulties in falling asleep and sleeping through, nightmares, nervousness and psychomotor restlessness. The students are challenged to identify possible differential diagnoses and further get to know the patient's personal history (loss of relatives due to war, torture and flight from home country). Further, the students are guided through the principles of fear conditioning including translational aspects like neurotransmitter signaling of PTSD pathomechanism (translational and research aspects like dopamine transporter gene polymorphism, long term potentiation and synaptic signaling). RESULTS/CONCLUSION: The case presentation comprises different learning aspects: First, declarative knowledge has to be acquired and collected in basic medical sciences, knowledge that is in fact available and can be accessed on the conscious and preconscious level in long-term memory. Second, associative learning leads to the formation of neuronal connections and is an important way of learning and discovering, founded in neural associations. Third, polythematic-crosslinking thinking is needed as ability to link information in a meaningful way. These steps are a typical intellectual ability of gifted learners and researchers that combine previously seemingly unrelated areas to each other and drive innovation.

Chikungunya vaccines in development.

Chikungunya virus has become a global health threat, spreading to the industrial world of Europe and the Americas; no treatment or prophylactic vaccine is available. Since the late 1960s much effort has been put into the development of a vaccine, and several heterogeneous strategies have already been explored. Only two candidates have recently qualified to enter clinical phase II trials, a chikungunya virus-like particle-based vaccine and a recombinant live attenuated measles virus-vectored vaccine. This review focuses on the current status of vaccine development against chikungunya virus in humans and discusses the diversity of immunization strategies, results of recent human trials and promising vaccine candidates.