Conservative Management of Type 2 Endoleaks is not Associated with Increased Risk of Aneurysm Rupture

AbstractObjectiveEndovascular repair (EVAR) of abdominal aortic aneurysms (AAAs) has led to a reduction in the perioperative mortality when compared with open repair. However, re-intervention for complications, such as endoleak, may be required in up to 20% of the cases. Controversy exists over the management of Type 2 endoleaks. This study examined the outcomes of patients with Type 2 endoleaks treated conservatively to inform the ongoing management debate.MethodsAll patients with a confirmed Type 2 endoleak after EVAR for an infrarenal AAA were included in the study. Data regarding device details, endoleak and time point, aneurysm sac growth, intervention and outcome were collected retrospectively from case notes and the vascular research database.ResultsForty-one Type 2 endoleaks were seen in 369 EVARs performed for infrarenal AAA between March 1994 and June 2006. Twenty-five were isolated Type 2 endoleaks and 16 occurred in conjunction with other endoleaks. Of the 25 isolated Type 2 endoleaks, 18 (72%) patients demonstrated no increase in sac size, six (24%) patients showed an enlargement of the sac and one patient was lost to follow-up. Only one patient underwent intervention for an isolated Type 2 endoleak. After a mean follow-up period of 4 years, approximately half of the patients (48%) remain under observation (with an enlarging or stable sac), whilst the others (48%) have spontaneously sealed. Only five patients under surveillance (20%) have an enlarging sac. There were no ruptured aneurysms or aneurysm-related deaths and no patients required conversion to open repair.ConclusionsIn this study, a policy of regular surveillance for Type 2 endoleaks was not associated with any adverse events. We therefore advocate the conservative approach for Type 2 endoleaks

Is Infrainguinal Bypass Grafting Successful Following Failed Angioplasty?

ObjectivesAngioplasty is often used in the management of lower limb ischaemia and can reduce the need for infrainguinal bypass in some patients. There is an associated failure rate with this technique and bypass surgery is often used in this situation as a secondary limb salvage procedure. We aimed to evaluate the outcome of infrainguinal bypass grafting following failed attempt at angioplasty.MethodsAll cases of infrainguinal bypass at a single centre over a seven year period were identified and notes reviewed. Cases were divided into four groups according to their indication for surgery; acute ischaemia, chronic critical ischaemia, failed angioplasty and an ‘other’ group including aneurysmal disease and claudicants. The failed angioplasty group was compared with the other three groups. Survival analysis was performed using Kaplan Meier curves and groups compared in terms of long term patency and survival.ResultsPrimary patency was 61.2% in the failed angioplasty group at 12 months compared with 60.6% in the other groups (P=1.11). There was also no significant difference in primary patency at 60 months (50% vs 40.6%, P=0.26). Survival at 12 months was also comparable between the groups (failed angioplasty group 74.2% compared with 77.3% in the other groups, P=0.662) as was 60 months survival (33.3% and 35.4% respectively, P=0.166).DiscussionIn this study, outcome of infrainguinal bypass following failed angioplasty was comparable to outcome of surgery performed for another indication. This paper supports the use of distal bypass surgery for limb salvage in cases where minimal access techniques have failed

Grain Surface Models and Data for Astrochemistry

AbstractThe cross-disciplinary field of astrochemistry exists to understand the formation, destruction, and survival of molecules in astrophysical environments. Molecules in space are synthesized via a large variety of gas-phase reactions, and reactions on dust-grain surfaces, where the surface acts as a catalyst. A broad consensus has been reached in the astrochemistry community on how to suitably treat gas-phase processes in models, and also on how to present the necessary reaction data in databases; however, no such consensus has yet been reached for grain-surface processes. A team of ∼25 experts covering observational, laboratory and theoretical (astro)chemistry met in summer of 2014 at the Lorentz Center in Leiden with the aim to provide solutions for this problem and to review the current state-of-the-art of grain surface models, both in terms of technical implementation into models as well as the most up-to-date information available from experiments and chemical computations. This review builds on the results of this workshop and gives an outlook for future directions

Conservative Management of Type 2 Endoleaks is not Associated with Increased Risk of Aneurysm Rupture

AbstractObjectiveEndovascular repair (EVAR) of abdominal aortic aneurysms (AAAs) has led to a reduction in the perioperative mortality when compared with open repair. However, re-intervention for complications, such as endoleak, may be required in up to 20% of the cases. Controversy exists over the management of Type 2 endoleaks. This study examined the outcomes of patients with Type 2 endoleaks treated conservatively to inform the ongoing management debate.MethodsAll patients with a confirmed Type 2 endoleak after EVAR for an infrarenal AAA were included in the study. Data regarding device details, endoleak and time point, aneurysm sac growth, intervention and outcome were collected retrospectively from case notes and the vascular research database.ResultsForty-one Type 2 endoleaks were seen in 369 EVARs performed for infrarenal AAA between March 1994 and June 2006. Twenty-five were isolated Type 2 endoleaks and 16 occurred in conjunction with other endoleaks. Of the 25 isolated Type 2 endoleaks, 18 (72%) patients demonstrated no increase in sac size, six (24%) patients showed an enlargement of the sac and one patient was lost to follow-up. Only one patient underwent intervention for an isolated Type 2 endoleak. After a mean follow-up period of 4 years, approximately half of the patients (48%) remain under observation (with an enlarging or stable sac), whilst the others (48%) have spontaneously sealed. Only five patients under surveillance (20%) have an enlarging sac. There were no ruptured aneurysms or aneurysm-related deaths and no patients required conversion to open repair.ConclusionsIn this study, a policy of regular surveillance for Type 2 endoleaks was not associated with any adverse events. We therefore advocate the conservative approach for Type 2 endoleaks

Interstadial rise and Younger Dryas demise of Scotland\u27s last ice fields

Establishing the atmospheric expression of abrupt climate change during the last glacial termination is key to understanding driving mechanisms. In this paper, we present a new 14C chronology of glacier behavior during late-glacial time from the Scottish Highlands, located close to the overturning region of the North Atlantic Ocean. Our results indicate that the last pulse of glaciation culminated between ~12.8 and ~12.6 ka, during the earliest part of the Younger Dryas stadial and as much as a millennium earlier than several recent estimates. Comparison of our results with existing minimum-limiting 14C data also suggests that the subsequent deglaciation of Scotland was rapid and occurred during full stadial conditions in the North Atlantic. We attribute this pattern of ice recession to enhanced summertime melting, despite severely cool winters, and propose that relatively warm summers are a fundamental characteristic of North Atlantic stadials.his work was supported by NSF grant EAR‐9118375 and National Geographic/WAITT Foundation grant 450‐16. A.E. Putnam acknowledges support from the Comer Family Foundation, the Lenfest Foundation, a Lamont‐Doherty Earth Observatory postdoctoral fellowship, and NSF grant EAR‐1554990. The data reported and discussed in this paper are listed in the references, tables, and supporting information