Myocardial Bridging: A Meta‐Analysis of Prevalence

The main objective of this article was to analyze prevalence data about myocardial bridging (MB) in published studies. To this purpose, we performed a meta‐analysis of studies published in English literature that contained data about the prevalence of MB and its anatomical characteristics. The overall prevalence was 19% (CI: 17–21%); autopsy studies revealed an overall prevalence of 42% (CI: 30–55%), CT studies 22% (CI: 18–25%), and coronary angiography 6% (CI: 5–8%). Most bridges were located on the left anterior descending artery (82% overall, 63% on autopsy studies), had a mean thickness of 2.47 mm and a mean length of 19.3 mm. In conclusion, autopsy studies should be the gold standard in evaluating the actual prevalence of myocardial bridges, while in vivo high‐resolution CT scanning should be preferred to coronary angiography studies.     

Sudden Cardiac Death in a Young Man with Migraine-associated Arrhythmia

A 31-year-old man with migraine-induced syncope and bradycardia with subsequent pacemaker implantation died unexpectedly. Clinically unsuspected cardiac anomalies were found at autopsy including myocardial bridging of the left anterior descending artery and shelf-like coronary artery ostia. Nortriptyline was identified by toxicologic analysis. A review of the autopsy findings, the historical information, and the effects of the possible arrhythmogenic circumstances is undertaken and the potential contributions to the death are discussed. Cardiac arrhythmias have been documented during migraines. Coronary artery bridging has been known to lead to ischemia and infarction, ventricular tachycardia, and sudden death; however, these are very rare sequelae. Congenital coronary artery anomalies have been linked to sudden cardiac death, but only rarely cause death in people younger than 31 years. Migraines and the autopsy findings described have been associated with cardiac arrhythmia and sudden death. Altogether, they led to the unexpected death of this young man.     

Social capital and support for the welfare state in Russia

Few tasks are more important in a post-communist setting than rebuilding the welfare state. We study individual preferences for increasing social welfare spending to reduce inequality. Using two surveys of about 34,000 and 37,000 Russians, we show the great importance of the “bridging” type of social capital for redistribution preferences in Russia, as it precludes possibilities of cheating and free-riding on the welfare state. Instrumenting social capital with education, climate, and distance from Moscow, we deal with endogeneity concerns and also contribute to our understanding of the deep roots of social capital in Russia. We claim that social capital in post-socialist countries could help mobilize public support for redistribution even where institutions are weak.     

Social Capital and the Number of Governments within a County: A Potential Problem with Social Capital

Social capital has been demonstrated to be a benefit to a community in a variety of ways. However, researchers have begun to point out that social capital does have a downside. Communities that use bonding social capital to mobilise residents to action have the potential to exclude outsiders from their communities. The number of governments in a county could be used as an indicator of bonding social capital within a region. Residents use their local government to create and pass laws that have the potential to exclude others. The current analysis used the number of governments as a proxy for bonding social capital. Findings demonstrate that as the level of bonding social capital (the number of governments) increased the social capital in the county increased. Residents use their bonding social capital to respond to others, which then increases the level of social capital to be able to mobilise in the future.     

Computer Simulations to Investigate the Consequence of Blunt Head Impact

Blunt head impact as sustained in falls or punches against the head can result in rupture of bridging veins. Computer simulations were performed to simulate three different types of falls and punches against the head. The relative brain‐skull motion was recorded. The falls resulted in impact on the backside of the head, whereas the punches struck the face. The maximum resultant translational and rotational acceleration, the Head Injury Criterion (HIC), and the characteristics of the relative brain‐skull motion, as well as the coup and contre‐coup regions were determined. The maximum resultant translational acceleration was found to be between 2982 and 3541 m/s² for falls and between 814 and 942 m/s² for punches. The maximum resultant rotational acceleration reached 632–1000 rad/s² for falls and 252–620 rad/s² for punches. The HIC for falls was found to be at least 1357 and at most 130 for punches. The major brain‐skull displacement calculated for falls and punches was 6.6 and 4.2 mm, respectively. The results of this study suggest that falls are associated with a higher risk for bridging vein ruptures than punches and that cerebral contusions at the contre‐coup side are more serious.     

A Bridge Too Far? Examining Bridging Assumptions in Common-Space Estimations

While most common-space estimations rely upon members who served in both the House and Senate as “bridges” to scale the remaining members, this assumes that these “bridge members” do not change their preferences when they change chambers. Such an assumption conflicts with standard notions of representation, that is, that legislators’ votes reflect (at least to some degree) the wishes of their constituents. We examine the constancy of this common-space voting assumption by focusing on a subset of House members who move to the Senate: those who come from statewide House districts. Using these members as the bridge actors—and thus bridging by constituency explicitly—in a one-dimensional item response theory model, we find that the standard assumption of chamber switchers in common-space estimations is technically, but immaterially, false. While there are statistically distinguishable differences in House and Senate voting records for chamber switchers, they are not sufficiently large to meaningfully undermine bridging.     

Rapid knowledge: ‘Bridging research and policy’ at the Overseas Development Institute

Numerous organizations advocate the need to ‘bridge research and policy’. Philanthropic foundations, national social science funding regimes and international organizations have sought to improve knowledge utilization. Similarly, research consumers such as NGOs and government departments complain of research irrelevance for policy purposes. The concern of this article is with ‘evidence informed policy’ within the field of international development in which the Overseas Development Institute (ODI), a London‐based think tank, forms the case study. Most think tanks are driven by the need to influence immediate political agendas but ODI has also developed organizational strategies of policy entrepreneurship that extend to longer term influence through creating human capital, building networks and engaging policy communities. Copyright © 2009 John Wiley & Sons, Ltd.     

冠状动脉肌桥与心源性猝死

冠状动脉肌桥也称冠脉肌桥或心肌桥,是一种先天性冠状动脉分布走行的发育畸形,为冠状动脉某一段或其分支的某一段走行于心外膜下的心肌层内。这种先天性冠状动脉分布走行的发育畸形可以引起猝死,在尸体解剖中也较为常见。本文对冠脉肌桥的形态学特点、临床影像学与心电图改变、猝死机制以及法医学鉴定中需要注意的问题等方面进行了阐述。