Evaluation of enoxaparin for bridging of warfarin in outpatients with left ventricular assist devices (LVADs).

BACKGROUND: Patients with left ventricular assist devices (LVADs) require systemic anticoagulation. The use of enoxaparin for bridging to warfarin remains understudied in this population. METHODS: This single-center retrospective study was performed to characterize enoxaparin use and associated thrombotic and bleeding outcomes in adult outpatients with LVADs from January 2018 to July 2021. RESULTS: Fifty-four enoxaparin bridging events were evaluated in 49 patients. Most patients with HeartMate II (HM2) and HeartWare (HVAD) devices received enoxaparin dosed 1 mg/kg every 12 h. In patients with HeartMate 3 (HM3) devices, an equal number of patients received 0.5 mg/kg every 12 h and 1 mg/kg every 12 h, with a smaller subset receiving intermediate doses. The median duration of bridging was 6 days (4-8 [IQR]). One major bleeding event required discontinuation of enoxaparin and hospitalization in a patient with an HM3 device. Thrombotic events occurred in four patients with two incidents of pump thrombosis requiring pump exchange and two ischemic strokes. All thrombotic events occurred in patients with HVAD or HM2 devices. CONCLUSION: These results suggest that enoxaparin bridging in LVAD patients was well-tolerated with low bleeding and thrombotic rates, particularly with the HM3 device.

Redefining genomic privacy: trust and empowerment.

Fulfilling the promise of the genetic revolution requires the analysis of large datasets containing information from thousands to millions of participants. However, sharing human genomic data requires protecting subjects from potential harm. Current models rely on de-identification techniques in which privacy versus data utility becomes a zero-sum game. Instead, we propose the use of trust-enabling techniques to create a solution in which researchers and participants both win. To do so we introduce three principles that facilitate trust in genetic research and outline one possible framework built upon those principles. Our hope is that such trust-centric frameworks provide a sustainable solution that reconciles genetic privacy with data sharing and facilitates genetic research.

Data Safe Havens in health research and healthcare.

MOTIVATION: The data that put the 'evidence' into 'evidence-based medicine' are central to developments in public health, primary and hospital care. A fundamental challenge is to site such data in repositories that can easily be accessed under appropriate technical and governance controls which are effectively audited and are viewed as trustworthy by diverse stakeholders. This demands socio-technical solutions that may easily become enmeshed in protracted debate and controversy as they encounter the norms, values, expectations and concerns of diverse stakeholders. In this context, the development of what are called 'Data Safe Havens' has been crucial. Unfortunately, the origins and evolution of the term have led to a range of different definitions being assumed by different groups. There is, however, an intuitively meaningful interpretation that is often assumed by those who have not previously encountered the term: a repository in which useful but potentially sensitive data may be kept securely under governance and informatics systems that are fit-for-purpose and appropriately tailored to the nature of the data being maintained, and may be accessed and utilized by legitimate users undertaking work and research contributing to biomedicine, health and/or to ongoing development of healthcare systems. RESULTS: This review explores a fundamental question: 'what are the specific criteria that ought reasonably to be met by a data repository if it is to be seen as consistent with this interpretation and viewed as worthy of being accorded the status of 'Data Safe Haven' by key stakeholders'? We propose 12 such criteria. CONTACT: paul.burton@bristol.ac.uk.

Endovascular abdominal aortic aneurysm repair using an anatomical fixation technique and concomitant suprarenal orientation: results of a prospective, multicenter trial.

BACKGROUND: Endovascular repair of abdominal aortic aneurysms with the Endologix Powerlink System has been shown to be a safe and effective alternative to open surgery in patients having an aortic neck diameter of up to 26 mm. We report the mid-term outcomes of an endovascular repair approach wherein the infrarenal bifurcated stent graft was placed at the aortoiliac bifurcation, with concomitant placement of a proximal extension having suprarenal orientation for proximal sealing. METHODS: Between 2006 and 2008, eight US sites enrolled 44 consecutive eligible patients presenting with abdominal aortic aneurysm in a prospective, single arm pivotal trial approved by the Food and Drug Administration. Each patient received a Powerlink infrarenal bifurcated stent graft through anatomical fixation at the aortoiliac bifurcation and a suprarenal extension to achieve proximal sealing. Analysis of the primary endpoint (proximal type I endoleak) was evaluated using contrast-enhanced computed tomography scans at 30 days, with on-going long-term follow-up for safety and treatment effectiveness. RESULTS: Patients (89% male) presented at a mean age of 70 ± 10 years with mean maximal aneurysm sac diameter of 5.5 cm. Challenging infrarenal aortic neck anatomy was present in 93% of patients. Technical success was 100% over a mean procedure time of 129 minutes. No aneurysm-related deaths, conversions, ruptures, migrations, or type III or IV endoleaks have been observed. The majority of endoleaks (80%) observed to date are type II. Currently, the primary clinical success rate is 93%. Two endovascular secondary procedures have been performed for resolution of type IA or type IB endoleak, and one surgical intervention was performed for resolution of limb occlusion. Significant reduction in sac diameter is observed to up to 2 years. CONCLUSIONS: The combination of an anatomically-fixed Powerlink infrarenal bifurcated stent graft and a suprarenal proximal extension safely and effectively excludes aneurysms in eligible patients. Longer term follow-up will determine the durability of these findings.

One-stage triple hybrid arch debranching.

Traditionally, repair of complex arch and descending aortic disease has required a two-stage surgical approach. We describe a novel one-stage repair that combines primary revascularization of the subclavian with stent coverage of diffuse aortic disease. A 31-year-old woman with Marfan syndrome presented with a growing arch aneurysm. At age 16 years, she had undergone the Ross procedure followed by a redo sternotomy and valve conduit. On follow-up, a distal arch aneurysm measuring 6 cm with an aneurysmal upper thoracic aorta and a localized distal thoracic aortic dissection was identified. In one stage, triple hybrid off-pump arch debranching with endovascular stent grafting was performed using two GORE Hybrid Vascular Grafts to perform the distal left carotid and subclavian anastomoses, which provided complete primary arch debranching without requiring a carotid-subclavian shunt. The patient had no complications, was discharged home on postoperative day 3, and continues to do well 3 months postoperatively. We conclude that one-stage repair of complex aortic arch disease with primary revascularization of the subclavian is feasible.

A simplified approach to evaluate human and aquatic exposure to a chemical spilled in a river.

This study presents an approach and a model to evaluate the potential exposure from an episodic chemical spill into a river. The River Dilution Model (RDM) was developed to predict chemical concentrations in a river as a function of the downstream distance and the time after an instantaneous release. RDM is one-dimensional dilution model in an Excel spreadsheet which allows for a quick screening appraisal. RDM predictions showed reasonably good agreement with measured values of peak concentration and arrival time at distances of 3.1-7.7 km downstream of the dye release point. RDM significantly over predicted peak concentrations at greater distances because it did not consider chemical removal processes occurring in the long travel time. This paper describes how to use the predicted chemical concentrations to assess the potential human and aquatic hazards. Several sources of information were identified to define model input and toxicity information. RDM and the approach were applied in a case study to demonstrate how to evaluate the potential hazard for a spill of hydraulic fluid. The approach will enable facilities to assess potential impacts with readily available tools, and then decide which engineering or administrative controls are needed to prevent or manage a chemical spill.