Percutaneous Transhepatic Venous Access for Left Atrial Appendage Closure in a Patient with Left Sided Inferior Vena Cava with Hemiazygos Continuation.

The transfemoral venous approach is the standard for Left Atrial Appendage Closure (LAAC) using the WATCHMAN device. However in patients without a patent inferior vena cava, an alternate access site can be utilized. We present a case of a patient with left sided inferior vena cava with hemiazygos continuation who had clinical indication for LAAC and in whom a transhepatic approach was successfully utilized.

Comparison of Drug Benefits Provided by Veterans Affairs Canada and the Canadian Forces Health Services Group.

BACKGROUND: Drug benefits are provided at public expense to all actively serving Canadian Armed Forces (CAF) personnel, with ongoing drug coverage offered by Veterans Affairs Canada (VAC) for selected conditions following termination of employment. Differences in drug coverage between these programs could introduce risks for treatment disruption. OBJECTIVES: Work was undertaken to establish a process that would allow systematic comparison of the entire VAC and CAF formularies, and to identify and explain discordant listings in 14 therapeutic categories that pose risk of adverse outcomes with sudden treatment interruption. METHODS: Lists of medications were created for each program, including regular benefit and restricted use drugs, using files obtained from the claims processor in January 2015. Products were coded using the Anatomic-Therapeutic-Chemical (ATC) system. Degree of alignment within therapeutic categories was assessed based on the percentage of fifth-level ATCs that were covered in common. Discordantly listed drugs in 14 categories of concern were reviewed to identify similarities in product characteristics. RESULTS: A total of 1124 medications were identified in 80 therapeutic categories. Coverage of medications was identical in 11 categories, and overall, almost three-quarters of identified drugs (73.4%, n = 825) were covered in common by both plans. Many discordant listings reflected known differences in the programs' operating procedures. A number of discrepancies were also identified in newer therapeutic categories. CONCLUSIONS: There is significant overlap in the medications covered by the CAF and VAC drug benefit programs. Application of the ATC coding system allowed for discrepancies to be readily identified across the entire formulary, and in specific therapeutic categories of concern.

The role of dyking and fault control in the rapid onset of eruption at Chaitén volcano, Chile.

Rhyolite is the most viscous of liquid magmas, so it was surprising that on 2 May 2008 at Chaitén Volcano, located in Chile's southern Andean volcanic zone, rhyolitic magma migrated from more than 5 km depth in less than 4 hours (ref. 1) and erupted explosively with only two days of detected precursory seismic activity. The last major rhyolite eruption before that at Chaitén was the largest volcanic eruption in the twentieth century, at Novarupta volcano, Alaska, in 1912. Because of the historically rare and explosive nature of rhyolite eruptions and because of the surprisingly short warning before the eruption of the Chaitén volcano, any information about the workings of the magmatic system at Chaitén, and rhyolitic systems in general, is important from both the scientific and hazard perspectives. Here we present surface deformation data related to the Chaitén eruption based on radar interferometry observations from the Japan Aerospace Exploration Agency (JAXA) DAICHI (ALOS) satellite. The data on this explosive rhyolite eruption indicate that the rapid ascent of rhyolite occurred through dyking and that melt segregation and magma storage were controlled by existing faults.

Accelerated uplift and magmatic intrusion of the Yellowstone caldera, 2004 to 2006.

The Yellowstone caldera began a rapid episode of ground uplift in mid-2004, revealed by Global Positioning System and interferometric synthetic aperture radar measurements, at rates up to 7 centimeters per year, which is over three times faster than previously observed inflation rates. Source modeling of the deformation data suggests an expanding volcanic sill of approximately 1200 square kilometers at a 10-kilometer depth beneath the caldera, coincident with the top of a seismically imaged crustal magma chamber. The modeled rate of source volume increase is 0.1 cubic kilometer per year, similar to the amount of magma intrusion required to supply the observed high heat flow of the caldera. This evidence suggests magma recharge as the main mechanism for the accelerated uplift, although pressurization of magmatic fluids cannot be ruled out.

Uplift, thermal unrest and magma intrusion at Yellowstone caldera.

The Yellowstone caldera, in the western United States, formed approximately 640,000 years ago when an explosive eruption ejected approximately 1,000 km3 of material. It is the youngest of a series of large calderas that formed during sequential cataclysmic eruptions that began approximately 16 million years ago in eastern Oregon and northern Nevada. The Yellowstone caldera was largely buried by rhyolite lava flows during eruptions that occurred from approximately 150,000 to approximately 70,000 years ago. Since the last eruption, Yellowstone has remained restless, with high seismicity, continuing uplift/subsidence episodes with movements of approximately 70 cm historically to several metres since the Pleistocene epoch, and intense hydrothermal activity. Here we present observations of a new mode of surface deformation in Yellowstone, based on radar interferometry observations from the European Space Agency ERS-2 satellite. We infer that the observed pattern of uplift and subsidence results from variations in the movement of molten basalt into and out of the Yellowstone volcanic system.