Multimodality Imaging Diagnostic Approach of Systemic-to-Pulmonary Vein Fistulae.

A 26-year-old man with a history of bilateral lung transplantation for pulmonary cystic fibrosis 6 months before was admitted in our institution for acute heart failure. Cardiac magnetic resonance imaging (CMR) showed an increased aortic output, as aortic flow assessed by velocity mapping was twofold the pulmonary flow, an occluded superior vena cava (SVC), and enlarged azygos vein. A systemic-to-pulmonary vein fistula (SAPVF) was suspected. The selective angiography showed numerous fistulae between intercostals, thyro-cervical, internal mammary arteries and pulmonary veins. The thoracic CT performed before the CMR, which was initially considered as normal, showed well these arteriovenous fistulae after 3D MIP reconstruction. This particular observation highlights the great value of multimodality imaging for the diagnosis of this rare pathology. The MR velocity mapping is a noninvasive imaging technique of great interest to guide the diagnosis of arteriovenous fistulae, and further indicating more invasive complementary imaging modalities like selective arterial angiography.

Discovery, Structure Elucidation, and Biological Characterization of Nannocystin†A, a Macrocyclic Myxobacterial Metabolite with Potent Antiproliferative Properties.

Microbial natural products are a rich source of bioactive molecules to serve as drug leads and/or biological tools. We investigated a little-explored myxobacterial genus, Nannocystis sp., and discovered a novel 21-membered macrocyclic scaffold that is composed of a tripeptide and a polyketide part with an epoxyamide moiety. The relative and absolute configurations of the nine stereocenters was determined by NMR spectroscopy, molecular dynamics calculations, chemical degradation, and X-ray crystallography. The compound, named nannocystin A (1), was found to inhibit cell proliferation at low nanomolar concentrations through the early induction of apoptosis. The mode of action of 1 could not be matched to that of standard drugs by transcriptional profiling and biochemical experiments. An initial investigation of the structure-activity relationship based on seven analogues demonstrated the importance of the epoxide moiety for high activity.

Cannabis use, ischemic stroke, and multifocal intracranial vasoconstriction: a prospective study in 48 consecutive young patients.

BACKGROUND AND PURPOSE: Our objective was to evaluate the relationship between cannabis use and ischemic stroke in a young adult population. METHODS: Forty-eight consecutive young patients admitted for acute ischemic stroke participated in the study. First-line screening was performed, including blood tests, cardiovascular investigations, and urine analysis for cannabinoids. If no etiology was found, 3D rotational angiography and cerebrospinal fluid analysis were performed. A control was planned through neurovascular imaging within 3 to 6 months. RESULTS: In this series, there was multifocal intracranial stenosis associated with cannabis use in 21% (n=10). CONCLUSIONS: Multifocal angiopathy associated with cannabis consumption could be an important cause of ischemic stroke in young people.

Safety and technical efficacy of pre-operative embolization of head and neck paragangliomas: A 10-year mono-centric experience and systematic review.

OBJECTIVES: To retrospectively evaluate the safety and technical success of pre-operative embolization (POE) of head and neck paragangliomas (HNP) in a single-center cohort over a 10-year period, and to benchmark our results with those derived from a systematic analysis of the available literature. METHODS: All consecutive HNP embolized between November 2010 and April 2020 were included and reviewed. In total, there were 27 HNP in 27 patients [8 (30%) males; 19 (70%) females; mean age 53 ± 16 years; range 30-86]. Embolization technique, total procedure time, dose area product (DAP), complications, rate of HNP devascularization, and technical success (i.e. ≥80% devascularization of the HNP) were recorded and analyzed. A systematic analysis on the safety and technical success of POE was then conducted according to the Systematic Reviews and Meta-Analyses (PRISMA) guidelines. RESULTS: Twenty-one (21/27; 78%) HNP were treated with an endovascular approach and 6/27 (22%) with a percutaneous or combined (endovascular/percutaneous) technique. Mean total procedure time and DAP were 108 ± 48 min (range 45-235) and 92.5 ± 61.3 Gy·cm2 (range 19.9-276.0), respectively. Two (2/27; 7%) complications (one minor, one major) were observed. Mean HNP devascularization was 88 ± 15% (range 23-100) with technical success achieved in 24/27 (89%) HNP. Literature analysis revealed a pooled rate of complication and technical success of 3.8% (95% CI: 0.5-8.8%) and 79.0% (95% CI: 63.6-91.6%), respectively. CONCLUSIONS: POE of HNP is safe and results in extensive devascularization in the majority of treated tumors.

Embolisation of pulmonary arteriovenous malformations using high-frequency jet ventilation: benefits of minimising respiratory motion.

BACKGROUND: To evaluate patient radiation dose and procedural duration recorded during pulmonary arteriovenous malformation (PAVM) embolisation performed using high-frequency jet ventilation (HFJV) as compared with conventional intermittent positive pressure ventilation (IPPV) METHODS: Patients undergoing PAVM embolisation with HFJV assistance after April 2017 were retrospectively identified as group A, and those treated with IPPV before April 2017 as group B. Primary outcomes were patient radiation dose and procedural duration between groups A and B. Secondary outcomes were difference in diaphragmatic excursion between groups A and B, in group A with/without HFJ assistance, technical/clinical success, and complications. RESULTS: Twelve PAVMs were embolised in 5 patients from group A, and 15 PAVMs in 10 patients from group B. Mean patient radiation was significantly lower in group A than in group B (54,307 ± 33,823 mGy cm2 [mean ± standard deviation] versus 100,704 ± 43,930 mGy cm2; p = 0.022). Procedural duration was 33.4 ± 16.1 min in group A versus 57.4 ± 14.9 min in group B (p = 0.062). Diaphragmatic excursion was significantly lower in group A (1.3 ± 0.4 mm) than in group B (19.7 ± 5.2 mm; p < 0.001) and lower with near statistical significance in group A with HFJV than without HFJV (1.3 ± 0.4 mm versus 10.9 ± 3.1 mm; p = 0.062). Technical and clinical success was 100% in both groups, without relevant complications. CONCLUSION: HFJV-assisted PAVM embolisation is a safe, feasible technique resulting in reduced patient radiation doses and procedural time.

Pulmonary Arteriovenous Malformations Embolized Using a Micro Vascular Plug System: Technical Note on a Preliminary Experience.

AIM: To report our preliminary experience using a Micro Vascular Plug (MVP) deployed through a 2.8Fr micro-catheter for the treatment of pulmonary arteriovenous malformations (PAVMs) in a cohort of patients affected by Hereditary Haemorrhagic Telangiectasia (HHT). MATERIALS AND METHODS: Four consecutive female patients (mean age 38.0 years; range 25-55 years) with PAVMs diagnosed on echocardiogram/bubble test and contrast-enhanced CT (CECT) underwent MVP embolization. One patient was symptomatic with recent transient ischaemic attack. Follow-up was undertaken at 1-month post-procedure with CECT to assess PAVMs permeability and MVP positioning and at 1-, 6-, and 12-month post-procedure, with echocardiography/bubble test and standard neurological history, to confirm absence of right-to-left shunts and recurrent symptoms. RESULTS: Eight PAVMs were treated in 4 patients over 5 interventional sessions (mean 1.6 PAVMs per session). All PAVMs were simple, with mean feeding artery diameter of 4.25 mm. Eight 6.5 mm MVPs were deployed in total (one per lesion). Technical success was 100%. Mean procedural time and patient dose per session were 70 min (range 40-70 min) and 53418 mGy.cm2 (range 6113-101628 mGy.cm2), respectively. No signs of reperfusion neither of MPV migration were noted at 1-month CECT follow-up. At early follow-up (mean 3.75 months; range 1-12 months), clinical success was 100% with no evidence of recurrent right-to-left shunt, and no neurological symptoms. No immediate or late complications were observed. CONCLUSIONS: MVP embolization of PAVMs appears technically feasible, safe, and effective at early follow-up. Further prospective studies are required to confirm long-term safety and efficacy of this promising technique.

Isolation, Co-Crystallization and Structure-Based Characterization of Anabaenopeptins as Highly Potent Inhibitors of Activated Thrombin Activatable Fibrinolysis Inhibitor (TAFIa).

Mature thrombin activatable fibrinolysis inhibitor (TAFIa) is a carboxypeptidase that stabilizes fibrin clots by removing C-terminal arginines and lysines from partially degraded fibrin. Inhibition of TAFIa stimulates the degradation of fibrin clots and may help to prevent thrombosis. Applying a lead finding approach based on literature-mining, we discovered that anabaenopeptins, cyclic peptides produced by cyanobacteria, were potent inhibitors of TAFIa with IC50 values as low as 1.5 nM. We describe the isolation and structure elucidation of 20 anabaenopeptins, including 13 novel congeners, as well as their pronounced structure-activity relationships (SAR) with respect to inhibition of TAFIa. Crystal structures of the anabaenopeptins B, C and F bound to the surrogate protease carboxypeptidase B revealed the binding modes of these large (~850 Da) compounds in detail and explained the observed SAR, i.e. the strong dependence of the potency on a basic (Arg, Lys) exocyclic residue that addressed the S1' binding pocket, and a broad tolerance towards substitutions in the pentacyclic ring that acted as a plug of the active site.

[Retroperitoneal haematoma and retropubic suburethral TVT tape. Report of two cases]. / Hématome rétro-péritonéal et bandelettes sous urétrales rétropubiennes de type TVT: à propos de 2 cas.

The authors report two cases of retroperitoneal haematoma following insertion of retropubic suburethral TVT tape. In the first case, haemodynamic instability required emergency admission to the intensive care unit. Due to persistent haemodynamic instability, interventional radiology was performed to localize and embolize the vessel responsible for the bleeding, resulting in stabilization of the patient's haemodynamic state. In the second patient, blood loss was well supported allowing simple surveillance of the size of the haematoma, which remained stable, and correction of anaemia. Significant vascular wounds are rare after TVT and may require multidisciplinary management. Information appears to be essential, particularly for patients treated on an outpatient basis, to avoid delayed management.

Region-growing segmentation of brain vessels: an atlas-based automatic approach.

PURPOSE: To propose an atlas-based method that uses both phase and magnitude images to integrate anatomical information in order to improve the segmentation of blood vessels in cerebral phase-contrast magnetic resonance angiography (PC-MRA). MATERIAL AND METHODS: An atlas of the whole head was developed to store the anatomical information. The atlas divides a magnitude image into several vascular areas, each of which has specific vessel properties. It can be applied to any magnitude image of an entire or nearly entire head by deformable matching, which helps to segment blood vessels from the associated phase image. The segmentation method used afterwards consists of a topology-preserving, region-growing algorithm that uses adaptive threshold values depending on the current region of the atlas. This algorithm builds the arterial and venous trees by iteratively adding voxels that are selected according to their grayscale value and the variation of values in their neighborhood. The topology preservation is guaranteed because only simple points are selected during the growing process. RESULTS: The method was performed on 40 PC-MRA images of the brain. The results were validated using maximum-intensity projection (MIP) and three-dimensional surface rendering visualization, and compared with results obtained with two non-atlas-based methods. CONCLUSION: The results show that the proposed method significantly improves the segmentation of cerebral vascular structures from PC-MRA. These experiments tend to prove that the use of vascular atlases is an effective way to optimize vessel segmentation of cerebral images.