P1898Prevalence and risk of DOACs inappropriate dosing in atrial fibrillation. An analysis of the Swiss-AF and BEAT-AF registries

Background

Direct oral anticoagulants (DOACs) have a similar efficacy in terms of stroke and mortality reduction as compared to Vitamin K-Antagonists (VKAs) and improved safety with regards to intracranial haemorrhage in patients with non-valvular atrial fibrillation (AF). Dose of DOACs needs to be adjusted according to age, weight, renal function and concomitant medication. Yet, off-label dosages have been reported in 11 - 45% of patients (on average 20%).

Purpose

To assess the prevalence of inappropriate DOAC-dosing according to the official prescribing information in two large prospective Swiss AF cohorts (Swiss-AF and BEAT-AF) and to evaluate its correlation with adverse clinical outcomes.

Methods

All 3267 patients taking oral anticoagulants were stratified at baseline as receiving DOACs (adequately dosed, under- or overdosed) or VKAs. Appropriateness of DOAC dosing was assessed based on age (≥80 years), weight (≤60kg) and renal function (serum creatinine ≥133μmol/l [apixaban]; creatinine clearence ≤50ml/min [all other DOACs]). Clinical outcomes were collected during a median follow-up of 2.96 years. Major adverse clinical events (MACE) consisted of a combination of myocardial infarction, cardiac death, ischemic stroke and systemic embolism. Safety was assessed by occurrence of any bleeding event.

Results

1902 patients (58%) were on VKAs and 1365 on DOACs (42%). In the DOAC group, 1149 patients received a dose consistent with drug labelling (84%), 133 (10%) received an inappropriately high and 83 (6%) an inappropriately low dose. Overdosed patients were older than those adequately treated and more likely female, had a lower BMI and a higher CHA2DS2-VASc score (4 vs. 3 points) (p<0.001 for all). Underdosed patients were more likely to have concomitant antiplatelet therapy (p<0.001). Both off-label groups were more likely to have a history of coronary artery disease, heart failure and chronic kidney disease (p<0.001). Kaplan-Meier cumulative incidence rates for the first occurrence of MACE or bleedings are provided in Figure 1. Overdosed patients had an almost two-fold higher risk of bleeding (9.0 vs. 5.0 events per 100 patient-years compared to correctly dosed DOACs and to VKAs) and a higher rate of MACE (5.1 vs. 2.3 events per 100 patient years compared to correctly dosed DOACs and 5.1 vs. 3.4 compared to VKAs). Underdosing did not seem to be associated with a relevant increase in ischemic or bleeding events as compared to correctly dosed DOACs and VKAs (see Figure 1).

Figure 1. Kaplan-Meier incidence curves

Conclusion

Inadequate DOACs dosing was found in 1 in 6 patients and correlated with a higher burden of comorbidities at baseline. Underdosing correlated with concomitant antiplatelet therapy. Overdosing was associated with adverse clinical outcome for ischemic and bleeding events.

Endovascular treatment of small intracranial aneurysms: three alternatives to coil occlusion

INTRODUCTION

Small intracranial aneurysms with a fundus diameter of 2 - 3 mm may rupture and are therefore potential targets for an endovascular approach in treatment. Currently available coil technology is less than optimal for the treatment of aneurysms within this size range. Even the smallest coils are sometimes too large. If such a minute coil can be introduced into a small aneurysm, the hemodynamic effect and the induced thrombosis are frequently inadequate to occlude the aneurysm sufficiently from the parent artery circulation.

METHODS

Three technical alternatives for the endovascular treatment of small intracranial aneurysms not suitable for coil occlusion are illustrated with the following three case descriptions.

RESULTS

Stent grafts are usable for the intracranial internal carotid artery and for the V4 segment. The stiffness of the stent and the high expansion pressures are the two major drawbacks. Coaxial deployment of two or more self-expanding porous stents can result in sufficient redirection of the blood flow to induce aneurysmal thrombosis. Deployment of multiple stents, however, may require several treatment sessions in order to allow for the integration of the stents into the vessel wall from session to session. A regular microcatheter can block aneurysmal inflow in aneurysms with a very narrow neck. This allows the occlusion of the aneurysm with an appropriate amount of highly concentrated, rapidly polymerizing glue. Polymer emboli may result from excessive or rapid glue injection.

CONCLUSION

The available coil technology has inherent limitations in the treatment of very small intracranial aneurysms. Liquid embolic agents and stent-based extrasaccular treatment strategies may provide solutions for these challenging lesions.

Anästhesiologisches Management bei neuroendovaskulären Eingriffen

The endovascular treatment of diseases of intracranial and spinal vessels has become widely accepted in recent years. The patient is usually treated under general anesthesia and in choosing an appropriate anesthesia regimen and an optimized pre-interventional preparation, the anesthesiologist can influence the postinterventional result. The working environment in the angiography suite should address the requirements of a routine procedure and the necessities of complication management. Application of short-acting narcotics and relaxation of the patient if required, facilitate the intervention for both the neuroradiologist and the anesthesiologist. The patient should be supplied with everything needed before the intervention to avoid any waste of time in the case of an emergency (e.g., haemorrhage or fibrinolytic treatment). After the procedure the patient has to be monitored for at least 24 h. Peri-interventional and postinterventional complications, such as thrombo-embolism or hemorrhage, must be managed aggressively and consequently by the anesthesist to improve the postinterventional outcome. Therefore a close collaboration between the anesthesiologist and the neuroradiologist is essential.

A new device for endovascular coil retrieval from intracranial vessels: alligator retrieval device

The clinical use of a new device (Alligator Retrieval Device) designed specifically for endovascular foreign body (eg, coils) retrieval from intracranial vessels is reported. The Alligator has intrinsic advantages compared with microsnares for the endovascular catheter-based removal of coils.

HUMEX, a study on the survivability and adaptation of humans to long-duration exploratory missions, part I: lunar missions

The European Space Agency has recently initiated a study of the human responses, limits and needs with regard to the stress environments of interplanetary and planetary missions. Emphasis has been laid on human health and performance care as well as advanced life support developments including bioregenerative life support systems and environmental monitoring. The overall study goals were as follows: (i) to define reference scenarios for a European participation in human exploration and to estimate their influence on the life sciences and life support requirements; (ii) for selected mission scenarios, to critically assess the limiting factors for human health, wellbeing, and performance and to recommend relevant countermeasures; (iii) for selected mission scenarios, to critically assess the potential of advanced life support developments and to propose a European strategy including terrestrial applications; (iv) to critically assess the feasibility of existing facilities and technologies on ground and in space as testbeds in preparation for human exploratory missions and to develop a test plan for ground and space campaigns; (v) to develop a roadmap for a future European strategy towards human exploratory missions, including preparatory activities and terrestrial applications and benefits. This paper covers the part of the HUMEX study dealing with lunar missions. A lunar base at the south pole where long-time sunlight and potential water ice deposits could be assumed was selected as the Moon reference scenario. The impact on human health, performance and well being has been investigated from the view point of the effects of microgravity (during space travel), reduced gravity (on the Moon) and abrupt gravity changes (during launch and landing), of the effects of cosmic radiation including solar particle events, of psychological issues as well as general health care. Countermeasures as well as necessary research using ground-based test beds and/or the International Space Station have been defined. Likewise advanced life support systems with a high degree of autonomy and regenerative capacity and synergy effects were considered where bioregenerative life support systems and biodiagnostic systems become essential. Finally, a European strategy leading to a potential European participation in future human exploratory missions has been recommended.

Potential and benefits of closed loop ECLS systems on the ISS

To close open loops for long manned missions in space is a big challenge for aeronautic engineers throughout the world. The paper's focus is on the oxygen reclamation from carbon dioxide within a space habitat. A brief description of the function principle of a fixed alkaline electrolyzer, a solid amine carbon dioxide concentrator and a Sabatier reactor is given. By combining these devices to an air revitalization system the technical and economical benefits are explained. Astrium's Air Revitalization System (ARES) as a potential future part of the International Space Station's Environmental Control and Life Support System would close the oxygen loop. The amount of oxygen, needed for an ISS crew of seven astronauts could be provided by ARES. The upload of almost 1500 kg of water annually for oxygen generation through the onboard electrolyzer would be reduced by more than 1000 kg, resulting in savings of more than 30M$ per year. Additionally, the payload capacity of supply flights would be increased by this amount of mass. Further possibilities are addressed to combine ECLS mass flows with those of the power, propulsion and attitude control systems. Such closed loop approaches will contribute to ease long time missions (e. g. Mars, Moon) from a cost and logistic point of view. The hardware realization of Astrium's space-sized operating ARES is shown and test results of continuous and intermittent closed chamber tests are presented.

Incidence, severity, and mortality of acute respiratory failure in Berlin, Germany

A prospective multicenter study was carried out from October 1 to November 30, 1991, to determine the incidence, severity, and mortality of acute respiratory failure (ARF) in Berlin, Germany, a metropolis with a population of 3.44 million. Adult patients from 72 intensive care units (ICUs) were evaluated. ARF was defined as: (1) intubation and mechanical ventilation (I+MV) > or = 24 h; age > or = 14 yr. Incidence of ARF was assessed as the number of patients fulfilling ARF criteria within the 2-mo study period. Severity of ARF was defined as "no lung injury" (NLI), "mild-to-moderate lung injury" (MMLI), and "severe lung injury" (SLI) according to Murray and coworkers' proposals. Mortality was assessed as number of patients with ARF dying during ICU stay. During the study period, 508 patients were diagnosed as having ARF, representing an incidence of ARF of 88.6 per 100,000/yr. Twenty-four h after I+MV, MMLI occurred in 94% and SLI in 3.6% of the ARF patients. Overall mortality rate was 42.7%. Mortality rate in the NLI group was 36.4%; in patients with MMLI, 40.8%; and in patients with SLI, 58.8%. Our data offer novel information on incidence, severity, and mortality of ARF in a major urban population.

[Urinary cytology in office urology (author's transl)]

Urinary cytology is an effective method for the detection and control of urothelial tumors. The use of simple, fast staining and reliable techniques in the office for screening purposes may improve the early detection rate. A survey of simple microscopic and staining techniques is given. Prestained slides (Testsimplets and Sangodiff G) proved to be very suitable for office use. But the cytological analysis of the urinary sediment still needs a highly interested and trained examiner.