Clinical experience with electroanatomic mapping of ectopic atrial tachycardia

The aim of this study was to evaluate the clinical use of a new three-dimensional mapping system as a guide for catheter ablation of ectopic atrial tachycardia. A series of 42 consecutive patients with drug refractory ectopic atrial tachycardia was studied in a prospective observational trial with the electroanatomic mapping system CARTO. The arrhythmogenic focus was found in the right atrium in 30 patients and in the left atrium in 12 patients. The construction of a complete electroanatomic map of the right or left atrium was possible in 37 of 42 consecutive patients with ectopic atrial tachycardia. Mean activation time of the right atrium, including the proximal coronary sinus, was 94 +/- 25 ms for right atrial tachycardias; left atrial activation time during left atrial tachycardias was 86 +/- 17 ms. Average mapping time was 30 minutes for right atrial tachycardias and 22 minutes for left atrial tachycardias, allowing the collection of 86 +/- 50 and 65 +/- 28 catheter positions, respectively. The size of the area of earliest atrial activation calculated from the electroanatomic map amounted to 0.6 +/- 0.4 cm2 in right atrial tachycardias and 1.0 +/- 0.9 cm2 in left atrial tachycardias. In the right atrium the most common locations of the 33 arrhythmogenic foci in 30 patients were the high or mid-lateral right atrium (n = 10) and the inferoparaseptal region near the coronary sinus ostium (n = 7). Ectopic left atrial foci were most commonly located in an inferior position near the mitral annulus (n = 5) and in proximity to the ostium of the pulmonary veins (n = 4). Biatrial electroanatomic mapping allowed visualization of earliest right atrial activation during left atrial tachycardia at the high interatrial septum or near the coronary sinus ostium. Catheter ablation was successful in 85% of right atrial tachycardias and 82% of left atrial tachycardias. In patients with ectopic atrial tachycardia electroanatomic mapping is a safe and feasible technique that allows three-dimensional visualization of the automatic focus in a precise anatomic reconstruction of the atria. This novel mapping technology facilitates catheter ablation of complex ectopic atrial tachycardia.     

The anterolateral ligament is a distinct ligamentous structure: A histological explanation

Background

The aim was to determine whether the anterolateral ligament (ALL) had a histological structure that defined it as a real ligament.

Mechanisms of 5-hydroxytryptamine(2A) receptor activation of the mitogen-activated protein kinase pathway in vascular smooth muscle

5-Hydroxytryptamine (5-HT) activates the extracellular signal-regulated kinase (Erk) mitogen-activated protein kinases (MAPKs) in the vasculature, resulting in contraction. The mechanisms by which this occurs are unclear. G protein-coupled receptors can activate Erk MAPK pathways through a variety of mechanisms, including stimulation of Src, phosphoinositide-3 kinase (PI-3-K), protein kinase C (PKC), or the epidermal growth factor (EGF) receptor tyrosine kinase. We hypothesize that 5-HT uses one or more of these pathways. In isolated strips of rat aorta, the MAPK/Erk kinase inhibitor U0126 (50 microM), Src inhibitor PP1 (0.5 microM), PKC inhibitors calphostin C (1 microM) and chelerythrine (10 microM), and the PI-3-K inhibitor LY294002 (1-20 microM) reduced 5-HT-induced contraction. The EGF receptor tyrosine kinase inhibitor AG1478 (0.25-1 microM) was without effect. Thus, 5-HT activates PKC, Src, and possibly PI-3-K to result in contraction. In rat aortic myocytes, 5-HT (1 microM) activated Erk MAPK proteins 2- to 3-fold over basal values; activation was reduced by U0126, PP1, and LY294002 and unaffected by calphostin C or chelerythrine, wortmannin, or AG1478. The lack of effect of EGF receptor tyrosine kinase and PI-3-K inhibitors was confirmed in that the EGF receptor immunoprecipitated from 5-HT-exposed cells did not display an increase in autophosphorylation, nor did 5-HT significantly increase activation of Akt/protein kinase B, a downstream substrate for PI-3-K. These data suggest that the rat aortic 5-HT(2A) receptor uses Src but not PKC, PI-3-K, or the EGF receptor tyrosine kinase in stimulating Erk MAPK activation.     

Fidaxomicin for the treatment of <Emphasis Type="Italic">Clostridium difficile</Emphasis> infection (CDI) in at-risk patients with inflammatory bowel disease,fulminant CDI,renal impairment or hepatic impairment: a retrospective study of routine clinical use (ANEMONE)

Information is limited or lacking on fidaxomicin treatment of Clostridium difficile infection (CDI) in patients with inflammatory bowel disease, fulminant or life-threatening CDI, severe renal impairment, moderate-to-severe hepatic impairment and pregnancy. The ANEMONE study investigated fidaxomicin use in a routine clinical setting, focusing on these medical conditions of specific interest (MCSIs). This retrospective, post-authorisation study reviewed hospital records from Austria, Germany, Spain and the UK (June 2012–June 2015), collecting data from hospital admission to 30 days after last fidaxomicin dose. The primary objective was to identify the proportion of fidaxomicin-treated patients with MCSIs. Secondary objectives were to describe 30-day mortality, changes in ECG and laboratory parameters, fidaxomicin exposure and CDI response (resolution of diarrhoea; 30-day recurrence). 45.3% (261/576) of patients had ≥?1 MCSI. Thirty-day mortality (post-first dose) was 17.0% (98/576) in the total population and slightly higher (24.6–27.6%) in patients with fulminant CDI or severe renal impairment. 29.6% (24/81) deaths of known cause were attributable to CDI. Of changes in laboratory parameters or ECG findings, only a decrease in leucocyte counts appeared associated with fidaxomicin, consistent with a positive treatment response. Diarrhoea resolved in 78.0% (404/518) of treatment episodes; diarrhoea resolution was lowest in patients with fulminant CDI (investigator-defined, 67.5%, 56/88) and severe renal impairment (68.0%, 68/100). Thirty-day recurrence (18.8%, 79/420) was similar across MCSI subgroups. Although almost half of fidaxomicin-treated patients had ≥?1 MCSI, the majority of patients in all subgroups had positive responses to treatment, and no particular safety concerns were identified.     

Detection of MRSA in nasal swabs—marked reduction of time to report for negative reports by substituting classical manual workflow with total lab automation

In 2016, the workflow for MRSA detection in nasal swabs was changed from a classic-manual workflow to an automated workflow using total lab automation (TLA; BD Kiestra). This change entailed a reduction of the incubation time from 2 days to 20 h and reading of plates on weekdays and weekends instead of weekdays only. The workflow alteration did not include the introduction of 24/7. We wanted to follow up on the consequences for the times to report (TTR). We compared the TTR of all nasal swabs, which were sent for MRSA detection from June until August in 2015 (workflow—classic-manual) and in 2016 (workflow—automated). We calculated median TTR and interquartile ranges for the three possible reporting outcomes (negative, MRSA-known, MRSA-new) per day and workflow. A multivariable linear regression modeled the exposure variables workflow, day, and reporting outcome on TTR including interaction variables. The quantity and reasons for a TTR longer than 3 days were analyzed. During both 3-month periods, a total of 16,111 reports were issued (2015:7620; 2016:8491). The median TTR for negative reports was 48:28 (hh:mm) in 2015 and 23:58 in 2016. In the linear regression, all exposure variables had a strong and highly significant (p?<?0.001) influence on the TTR. The number of reports with a TTR longer than 3 days shrank from 2418 (2015) to 60 (2016). The workflow alteration halved the median TTR for negative reports and the number of reports with a TTR longer than 3 days was reduced by 97.5%.     

Hemicrania Continua: Beneficial Effect of Non‐Invasive Vagus Nerve Stimulation in a Patient With a Contraindication for Indomethacin

Hemicrania continua (HC) is a primary chronic headache disorder, characterized by a continuous and strictly unilateral headache, with possible cranial autonomic symptoms during episodes of pain exacerbation. The unilateral headache generally responds well to indomethacin; however, continuous indomethacin intake is often not tolerated due to severe adverse effects, like hypertension, gastrointestinal discomfort (especially if combined with aspirin), slightly increased risk of vascular events, and bronchial spasms. Therefore, alternative treatment options are desperately needed. Non‐invasive vagus nerve stimulation (nVNS) has been shown to be effective in patients with cluster headache, another trigeminal autonomic cephalalgia (TAC), with cranial parasympathetic autonomic activation during the attacks.     

Blunt chest trauma induces delayed splenic immunosuppression

Severe blunt chest trauma is frequently associated with multiple organ failure and sepsis. Posttraumatic immunosuppression seems to play a major role in their development. However, the immunologic alterations following pulmonary contusion are insufficiently elucidated. Specifically, it remains unknown whether immunocompetent cells located distant from the site of the impact are affected. We therefore aimed to characterize the influence of pulmonary contusion on lymphocytes and splenic macrophages. Male C3H/HeN mice (n = 8-10/group) were anesthetized and subjected to trauma or sham procedure. Blunt chest trauma was induced by a blast wave focused on the thorax. Two or 24 h later, splenocytes and splenic macrophages were isolated and stimulated for 48 h. The cytokine release (IFN-gamma, IL-2, IL-3, IL-10, IL-12, IL-18) from splenocytes as well as from splenic macrophages (TNF-alpha, IL-10, IL-12, IL-18) and plasma levels of TNF-alpha and IL-6 were quantified by ELISA. The results indicate that at 2 h after blunt chest trauma, plasma TNF-alpha and IL-6 were markedly increased. At the same time, no differences in splenocyte cytokine production were detectable. However, at 24 h a significantly depressed cytokine release was observed in trauma animals. Furthermore, splenic macrophages showed a significantly decreased production of TNF-alpha, IL-10, and IL-12 at 24 h and markedly increased release of IL-18 at 2 h after trauma. These results indicate that blunt chest trauma causes severe immunodysfunction of lymphocytes and splenic macrophages. Thus, lung contusion as a localized type of trauma causes dysfunction of immunocompetent cell populations, which are located distant from the site of injury.     

Dexamethasone in addition to metoclopramide for chronic nausea in patients with advanced cancer: a randomized controlled trial

Chronic nausea occurs in most patients with advanced cancer. This study was done to assess the antiemetic effects of dexamethasone in patients with chronic nausea refractory to metoclopramide. Secondary outcomes included appetite, fatigue, and pain. Fifty-one patients who had nausea (> or = 3/10 on a 0-10 scale) for > or = 2 weeks despite 48 hours of oral metoclopramide therapy (40-60 mg/day) were enrolled. Patients received 20 mg/day dexamethasone (DM) orally (n = 25) or placebo (n = 26) for severe nausea in addition to metoclopramide (60 mg/day orally). At baseline the mean nausea intensity ratings in the DM and placebo groups were 8.0 and 7.4. At Day 8 they were 2.1 and 2.0, respectively. At Day 3 and Day 8, the mean difference in nausea intensity for the DM and placebo groups was 4.5 and 2.9 (P = 0.16) and 5.9 and 5.7 (P = 0.85), respectively. Improvement in appetite and fatigue were observed on Day 3 and Day 8 in both groups as compared with the baseline. Pain, vomiting, well-being, and quality of life remained unchanged in both groups at both times. We conclude that DM was not superior to placebo in the management of chronic nausea in our patients with advanced cancer.     

Six steps from head to hand: a simulator based transfer oriented psychological training to improve patient safety

The incidence of human errors in the field of medicine is high. Two strategies to increase patient safety are simulator training and crew resource management (CRM) seminars, psychological courses on human performance and error management. AIM: To establish a CRM course combining psychological training on human error with simulator training. METHODS: Evaluation of a new 1-day training approach targeting physicians, nurses, and paramedics. The course was divided into four modules focusing on situation awareness, task management, teamwork, and decision-making. Each of the modules was set up according to a new six-step approach. The course started with an introduction into good CRM behaviour and an instructor demonstration of a simulator scenario. The participants had to debrief the instructors regarding their human performance. Step 2 was a lecture about the psychological background, and the third step consisted of psychological exercises related to the topic of the module. A psychological exercise in a medical context (MiniSim) made up step 4, which involved a patient simulator. The last two steps were a simulator scenario and a debriefing, as in other simulator courses. A psychologist and a physician were the facilitators in all steps. Two pilot courses were evaluated. RESULTS: Seventeen evaluation questionnaires were received. All participants rated the course as good (10) and very good (7). The psychological exercises were highly valued (good, 5; very good, 11 participants). Thirteen participants agreed that the course content was related to their work. CONCLUSION: We established the first course curriculum combining psychological teaching with simulator training for healthcare professionals in emergency medicine. Similar concepts using the six-step approach can be applied to other medical specialties.