Relation of quality of anticoagulation control with different management systems among patients with atrial fibrillation: data from FANTASIIA Registry

Original article[Abstract] Background. Anticoagulation control in patients with atrial fibrillation (AF) has a multidisciplinary approach although is usually managed by general practitioners (GP) or haematologists. The aim of our study was to assess the quality of anticoagulation control with vitamin K antagonists (VKAs) in relation to the responsible specialist in a “real‐world” AF population. Methods. We consecutively enrolled VKA anticoagulated patients included in the FANTASIIA Registry from 2013 to 2015. We analysed demographical, clinical characteristics and the quality of anticoagulation control according to the specialist responsible (ie GPs or haematologists). Results. Data on 1584 patients were included (42.5% females, mean age 74.0 ± 9.4 years): 977 (61.7%) patients were controlled by GPs and 607 (38.3%) by haematologists. Patients managed by GPs had higher previous heart disease (53.2% vs 43.3%, P < .001), heart failure (32.9% vs 26.5%, P < .008) and dilated cardiomyopathy (15.2% vs 8.7%, P < .001) with better renal function (69.3 ± 24.7 vs 63.1 ± 21.4 mL/min, P < .001) compared to patients managed by haematologists. There was no difference between groups in the type of AF, CHA2DS2‐VASc or HAS‐BLED scores, but patients with electrical cardioversion were more prevalent in GP group. The overall mean time in therapeutic range (TTR) assessed by Rosendaal method was 61.5 ± 24.9%; 52.6% of patients had TTR<65% and 60% of patients had TTR<70%. TTR was significantly lower in patients controlled by haematologists than by GPs (63 ± 24.4 vs 59.2 ± 25.6, P < .005). Conclusions. About 60% of AF patients anticoagulated with VKAs had poor anticoagulation control (ie TTR<70%), and their management was only slightly better than when it is managed by general practitioners.Instituto de Salud Carlos III; RD12/0042/0068Instituto de Salud Carlos III; RD12/0042/0010Instituto de Salud carlos III; RD12/0042/0069Instituto de Salud Carlos III; PI13/00513Instituto de Salud Carlos III; RD12/0042/006

Rapid automatic segmentation of abnormal tissue in late gadolinium enhancement cardiovascular magnetic resonance images for improved management of long-standing persistent atrial fibrillation

Background: Atrial fibrillation (AF) is the most common heart rhythm disorder. In order for late Gd enhancement cardiovascular magnetic resonance (LGE CMR) to ameliorate the AF management, the ready availability of the accurate enhancement segmentation is required. However, the computer-aided segmentation of enhancement in LGE CMR of AF is still an open question. Additionally, the number of centres that have reported successful application of LGE CMR to guide clinical AF strategies remains low, while the debate on LGE CMR’s diagnostic ability for AF still holds. The aim of this study is to propose a method that reliably distinguishes enhanced (abnormal) from non-enhanced (healthy) tissue within the left atrial wall of (pre-ablation and 3 months post-ablation) LGE CMR data-sets from long-standing persistent AF patients studied at our centre. Methods: Enhancement segmentation was achieved by employing thresholds benchmarked against the statistics of the whole left atrial blood-pool (LABP). The test-set cross-validation mechanism was applied to determine the input feature representation and algorithm that best predict enhancement threshold levels. Results: Global normalized intensity threshold levels T PRE = 1 1/4 and T POST = 1 5/8 were found to segment enhancement in data-sets acquired pre-ablation and at 3 months post-ablation, respectively. The segmentation results were corroborated by using visual inspection of LGE CMR brightness levels and one endocardial bipolar voltage map. The measured extent of pre-ablation fibrosis fell within the normal range for the specific arrhythmia phenotype. 3D volume renderings of segmented post-ablation enhancement emulated the expected ablation lesion patterns. By comparing our technique with other related approaches that proposed different threshold levels (although they also relied on reference regions from within the LABP) for segmenting enhancement in LGE CMR data-sets of AF patients, we illustrated that the cut-off levels employed by other centres may not be usable for clinical studies performed in our centre. Conclusions: The proposed technique has great potential for successful employment in the AF management within our centre. It provides a highly desirable validation of the LGE CMR technique for AF studies. Inter-centre differences in the CMR acquisition protocol and image analysis strategy inevitably impede the selection of a universally optimal algorithm for segmentation of enhancement in AF studies

Cell Science

Introduction Crawling cells move by using the actin cytoskeleton to power a simple mechanical cycle whereby the leading edge protrudes and adheres to the substratum. The cell body is then pulled forward in a process generally called retraction (Abercrombie, 1980; Roberts and Stewart, 2000). Delineating the mechanochemical events that drive this cycle has proven elusive because of the large number of proteins involved in cell locomotion and the intricacy of the intracellular control system. Moreover, the involvement of actin in a range of other cellular functions, such as endo- and exocytosis, trafficking and maintenance of cell shape, has frustrated the interpretation of many experiments. Therefore, we have focused on a simple and specialized cell: the sperm of a nematode, Ascaris suum. In these cells, the locomotion machinery is dramatically simplified, thereby providing a unique and powerful perspective for evaluating the molecular mechanism of cell crawling (Italiano et al., 2001