P754 Severe aortic stenosis with preserved ejection prognostic differences according to flow status and gradient fraction: a Spanish multicentre study

Background and objectives

Low-flow low-gradient (LFLG) aortic stenosis portends bad prognosis in different series. The objective of this study was to evaluate the evolution of this entity in our country.

Methods

We included 1394 consecutive patients evaluated between 2008-2016 with severe AS (AVA <1 cm²) and ejection fraction> 50% from 14 Spanish centres. The results (aortic valve intervention and mortality) were compared using the Kaplan-Meier survival analysis.

Results

Three groups based on gradient and flow status were established (high gradient: HG, normal flow under gradient: NFLG, low gradient low flow: LFLG). No significant demographic or clinical differences between groups were observed. After a follow-up of 61.52 months (IQR 43.5-86.5), 551 (73.8%) HG, 268 (35.4%) with NFLG and 81 (57.9%) LFLG received intervention, with a later surgery/TAVI indication in the LFLG group compared with HG group (p = 0.001) (Figure 1). The analysis of the Kaplan-Meier mortality curves showed no significant differences.

Conclusions

Patients with LFLG aortic stenosis with normal ejection fraction received less and later aortic valve intervention than the HG group with no significant differences in mortality.

Abstract P754 Figure. Time to surgery

474 Isolated pulmonary endocarditis

INTRODUCTION

Isolated pulmonary endocarditis is a rare entity, especially in patients without predisposing factors, being its current incidence less than 1% of the total cases of infectious endocarditis. This is due to the lower right heart pressures and a decrease of intravenous drug-consum, being most of the cases nowadays, related to congenital right-heart diseases or pacemakers and defibrillators implants.

CLINICAL CASE

A 35 year-old man, tobacco smoker and intravenous cocaine consumer since he was 25, was admitted to our Emergency Department for fever up to 40ºC, cough and dyspnea started three days before admission. In the anamnesis he refereed intravenous consum of cocaine and sharing of syringes the last week. On physical examination he was tachycardic and signs of heart right failure were present such as jugular ingurgitation and peripheral edema. No murmurs were heard. No respiratory failure was detected at any time. Blood test analysis showed high levels of protein C reactive and leukocytosis. Blood cultures were positive for S. aureus (OXA-S) in the first 24h. Chest X-ray (image 1) showed a necrotizing bilateral pneumonia that was confirmed with the presence of cavitated images in the pulmonary CT (image 2). Antibiotic treatment was started with daptomicine + cloxaciline. With the suspicion of right endocarditis a transthoracic echocardiography was performed, showing the presence of a big vegetation (4x1cm) on the pulmonary valve that caused moderate pulmonary insufficiency (images 3, 4). Neither tricuspid nor left side valves were involved. Biventricular function was conserved and hyperdynamic. Endocarditis diagnosis was definitive and due to the presence of multiple right embolisms and the big size of the vegetation, the patient underwent cardiac surgery. Intra-surgical finding demonstrated a big vegetation of almost 5 cm (image 5) depending of the posterior pulmonary valve that was removed; the posterior valve needed to be repaired. Posterior clinical evolution was correct without complications, completing 17 days of i.v. antibiotics (cloxaciline) before discharge.

CONCLUSIONS

Right endocarditis is a rapidly progressive disease due to the fact that staphylococcus are the most frequent microorganisms involved. Valvular destruction and secondary embolic phenomena are the rule. Tricuspid valve is involved most of the times being the isolated pulmonary valve affection very uncommon.

Abstract 474 Figure. CT, Echo and surgical images

P632 Apical mass after acute myocardial infarction

Funding Acknowledgements

No financial support

53-year-old male, with a personal history of high blood pressure and current smoking.

He presented in the emergency department with typical chest pain. The initial electrocardiogram showed a ST segment elevation in DI and AVL leads. An emergency coronariography was performed showing a single vessel disease with two tandem lesions on the first diagonal, which were treated with pharmacoactive stents.

An echocardiography was performed, showing a mild apicolateral hypokinesia, with good contractility of the remaing segments. In addition, a rounded, pediculated and mobile mass in the apex was observed; the mass was hyperechogenic compared to the myocardium. In this setting, the differential diagnosis should include thrombus in context of acute coronary syndrome (despite a small infarction with early revascularization and good contractility of the segments involved) vs. tumoral mass. Anticoagulant treatment was maintained and a cardiac magnetic resonance (MR) was performed. The MR showed an apical round mass of 11 mm, with hyperintense signal in both T1- and T2-enhanced sequences in comparison to normal myocardium; although no contrast uptake was observed in early gadolinium enhancement sequence, the mass showed homogeneous enhancement in the late enhancement images, both with optimal TI and with long T1. These findings were suggestive of a benign tumoral mass of atypical location. In addition, a small anterior subendocardial enhancement with preserved ejection fraction was observed.

A control echocardiogram after 5 weeks of anticoagulant treatment showed no changes in either size or characteristics of the mass. After risk-benefit assessment and according to patient preferences, surgical resection of the mass was decided by a mini-thoracotomy approach. A surgical piece was obtained, described as a mobile pediculated tumour with a granulated surface and mucinous aspect. The postoperative period was uneventful. Subsequently, the pathological study confirmed the diagnosis of papillary fibroelastoma of atypical location.

This case summarizes the usefulness of MR to characterize cardiac masses and, in particular, to differentiate tumours from thrombus. Although in this setting (recent myocardial infarction) an apical thrombus was initially suspected, the MR exam correctly identified a contrast enhanced mass, which ruled out acute thrombus and suggested benign tumour.

Abstract P632 Figure.

1094 Exercise syncope as initial symptom of constrictive pericarditis in a young patient

Introduction

Constrictive pericarditis is a form of diastolic heart failure that arises because an inelastic pericardium inhibits cardiac filling. Syncope is a rare initial symptom of constrictive pericarditis.

Clinical case

A 22-year-old man with previous medical history of viral meningitis when he was 3 months-old but without any family history of cardiac disease or sudden cardiac death, was admitted to the Emergency Department for syncope. During the last year, he had suffered several episodes of intense exercise-related syncope. The patient denied having prodromes, chest pain, palpitations or any other symptoms. The physical exam of the patient was normal with stable vital signs. Normal S1 and S2 heart sounds were present, no murmurs or gallop. There were no signs of heart failure, only a minimal jugular ingurgitation. An electrocardiogram (ECG) revealed sinus rhythm, signs of bi-atrial enlargement (prominent P-wave with P mitral morphology in DI-II leads, with enhanced negative deflection in V1), and negative asymmetric T-waves in inferior (DII-III-aVF) and V6 leads. Chest X-ray showed minimal calcium density in the inferior pericardial silhouette. The patient was admitted in the Cardiology Department for aetiological study. A transthoracic echocardiogram revealed a marked protodiastolic cleft in the interventricular septum, with 40% variations of the transmitral flow with the respiratory changes and dilation of the cava vein, with absent respiratory collapse. A marked thickening and calcification of the inferoposterior pericardium was also seen. Considering these results, the diagnosis of constrictive pericarditis was suggested (Fig. A, B, C). Blood tests for autoimmune disease screening, as well as infectious diseases, including Quantiferon test, HIV, HVC, HVB and other viral serologies were done, with negative results. A cardiac magnetic resonance was requested, which confirmed the echocardiographic findings, with bi-atrial enlargement and markedly thickened pericardium with loss of signal, suggestive of calcification. Left and right ventricle had normal dimensions and contractility. The CT coronary angiography revealed normal coronary anatomy. Extensive calcification and pericardial thickening were shown, with myocardial infiltration in the lateral-basal area (Fig D). It was considered important to rule out any additional arrhythmic aetiology of the exercise syncope. Therefore, a stress test and, an electrophysiologic study were done, both with normal results. The patient remained asymptomatic and a pericardiectomy was indicated given the severe thickening and calcification of the pericardium and frequent syncopal episodes that our patient suffered.

Conclusions

Syncope as the initial symptom in the absence of significant right heart failure signs is a very unusual form of presentation of idiopathic constrictive pericarditis given the severe thickening and calcification of the pericardium of our patient.

Abstract 1094 Figure.

Pharmacological MRI to investigate the functional selectivity of 5-HT1A receptor biased agonists

The emerging concept of "biased agonism" denotes the phenomenon whereby agonists can preferentially direct receptor signalling to specific intracellular responses among the different transduction pathways, thus potentially avoiding side effects and improving therapeutic effects. The aim of this study was to investigate biased agonism by using pharmacological magnetic resonance imaging (phMRI). The cerebral blood oxygen level dependent (BOLD) signal changes induced by increasing doses of two serotonin 5-HT_1A receptor biased agonists, NLX-112 and NLX-101, were mapped in anaesthetized rats. Although both compounds display high affinity, selectivity and agonist efficacy for 5-HT_1A receptors, NLX-101 is known to preferentially activate post-synaptic receptors, whereas NLX-112 targets both pre- and post-synaptic receptors. We used several doses of agonists in order to determine if the regional selectivity of NLX-101 was dose-dependent. NLX-112 and NLX-101 induced different positive and negative hemodynamic changes patterns at equal doses. Importantly, NLX-101 had no significant effect in regions expressing pre-synaptic receptors contrary to NLX-112. NLX-112 also produced higher BOLD changes than NLX-101 in the orbital cortex, the somatosensory cortex, and the magnocellular preoptic nuclei. In other regions such as the retrosplenial cortex and the dorsal thalamus, the drugs had similar effects. In terms of functional connectivity, NLX-112 induced more widespread changes than NLX-101. The present phMRI study demonstrates that two closely-related agonists display notable differences in their hemodynamic "fingerprints". These data support the concept of biased agonism at 5-HT_1A receptors and raise the prospect of identifying novel therapeutics which exhibit improved targeting of brain regions implicated in neuropsychiatric disorders. This article is part of the special issue entitled 'Serotonin Research: Crossing Scales and Boundaries'.

Is There a Role for GPCR Agonist Radiotracers in PET Neuroimaging?

Positron emission tomography (PET) is a molecular imaging modality that enables in vivo exploration of metabolic processes and especially the pharmacology of neuroreceptors. G protein-coupled receptors (GPCRs) play an important role in numerous pathophysiologic disorders of the central nervous system. Thus, they are targets of choice in PET imaging to bring proof concept of change in density in pathological conditions or in pharmacological challenge. At present, most radiotracers are antagonist ligands. In vitro data suggest that properties differ between GPCR agonists and antagonists: antagonists bind to receptors with a single affinity, whereas agonists are characterized by two different affinities: high affinity for receptors that undergo functional coupling to G-proteins, and low affinity for those that are not coupled. In this context, agonist radiotracers may be useful tools to give functional images of GPCRs in the brain, with high sensitivity to neurotransmitter release. Here, we review all existing PET radiotracers used from animals to humans and their role for understanding the ligand-receptor paradigm of GPCR in comparison with corresponding antagonist radiotracers.

Serotonin 5-HT1A Receptor Biased Agonists Induce Different Cerebral Metabolic Responses: A [18F]-Fluorodesoxyglucose Positron Emission Tomography Study in Conscious and Anesthetized Rats

Serotonin 5-HT_1A receptors constitute an attractive therapeutic target for various psychiatric or neurodegenerative disorders. These receptors are expressed in multiple brain regions on different neuronal populations and can be coupled with distinct G-protein subtypes; such functional diversity complicates the use of 5-HT_1A ligands in several pathologies where it would be desirable to stimulate the receptors in a precise region. Therefore, using "biased agonists" able to target specifically certain subpopulations of 5-HT_1A receptors would enable achievement of better therapeutic benefit. Several 5-HT_1A receptor biased agonists are currently in development, including NLX-101 (aka F15599) and NLX-112 (aka F13640, befiradol), with preclinical data suggesting that they preferentially target different populations of 5-HT_1A receptors. However, most previous studies used invasive and regionally limited approaches. In this context, [¹⁸F]-fluorodesoxyglucose (FDG)-positron emission tomography (PET) imaging constitutes an interesting technique as it enables noninvasive mapping of the regional brain activity changes following a pharmacological challenge in conscious animals. We report here the evaluation of cerebral glucose metabolism following intraperitoneal injection of different doses of NLX-112 or NLX-101 in conscious or isoflurane-anesthetized rats. The biased agonists produced different metabolic "fingerprints" with distinct regional preferences, consistent with previous studies. At equal doses, the effect of NLX-101 was less marked than NLX-112 in the piriform cortex, in the striatum (in terms of inhibition), and in the pontine nuclei and the cerebellum (in terms of activation); furthermore, only NLX-112 increased the glucose metabolism in the parietal cortex, whereas only NLX-101 induced a clear activation in the colliculi and the frontal cortex, which may be related to its distinctive procognitive profile. Both agonist effects were almost completely unapparent in anesthetized animals, underlining the importance of studying serotonergic neurotransmission in the conscious state. In this regard, [¹⁸F]FDG-PET imaging seems very complementary with other functional imaging techniques such as pharmacological MRI.

Implementation of Alere i Influenza A & B point of care test for the diagnosis of influenza in an ED

STUDY OBJECTIVE

This study aimed to evaluate the impact of implementing rapid point-of-care testing (POCT) with the Alere i Influenza A & B in an emergency department (ED) during an influenza epidemic.

METHODS

Direct nasal swabs were prospectively collected following the physical examination of patients aged >18years who presented to the ED of a tertiary hospital in France with influenza-like illness (ILI) symptoms (N=301) between February 1st and March 31st, 2016, which coincided with an influenza epidemic. Laboratory-based testing (standard of care) was used to obtain a diagnosis in February 2016 (pre-POCT cohort) and positive results were confirmed using polymerase chain reaction. The primary endpoint was patient time in the ED.

RESULTS

A total of 169 and 132 patients participated in the pre-POCT phase and POCT phase respectively. A significantly higher proportion of patients received a positive diagnosis in the POCT cohort compared with the pre-POCT cohort (31% versus 5.3%, P<0.01). Mean time spent in the ED and hospitalization rate were significantly lower in the POCT cohort (6.06h versus 4.15h, P=0.03, and 44.4% versus 9.7%, P=0.02, respectively). Despite similar rates in the prescription of antibiotics and antiviral therapies, the proportion of patients who were referred for additional tests was significantly lower in the POCT cohort (78.1% versus 62.1%, P=0.003, and 80.5% versus 63.6%, P=0.01, respectively).

CONCLUSIONS

The Alere i Influenza A & B POCT reduced the length of stay in ED, the hospitalization rates, and the number of additional diagnostic tests compared with standard of care testing.

Fibroma sinovial como causa atípica de síndrome de túnel del carpo: presentación de 2 casos clínicos

El fibroma sinovial (FS) es una tumoración benigna que puede encontrarse en la mano, teniendo predilección por las vainas flexoras. Esta lesión puede comportarse como una lesión ocupante de espacio (LOE), la cual puede llegar a comprimir nervios, como en el túnel del carpo, provocando un síndrome del túnel del carpo (STC). Este hecho solo ha sido descrito en 9 ocasiones. Cuando el STC se presenta de manera unilateral debemos descartar una LOE, entre las cuales el FS debería ser considerado como diagnóstico diferencial, especialmente frente al tumor de células gigantes, del cual solo es diferenciable microscópicamente, por lo que la resección de la masa es imprescindible. Los 2 casos aquí descritos tuvieron diferentes presentaciones clínicas pero sin complicaciones tras la resección.

S, Daly F, Nasri R, Ben Lakhal S, Paramba F, Purayil N, Naushad V, Mohammad O, Negi V, Chandra P, Kleinsasser A, Witrz MR, Buchner-Doeven JF, Tuip-de Boer AM, Goslings JC, Juffermans NP, Van Hezel M, Straat M, Boing A, Van Bruggen R, Juffermans N, Markopoulou D, Venetsanou K, Kaldis V, Koutete D, Chroni D, Alamanos I, Koch L, Jancik J, Rhodes H, Walter E, Maekawa K, Hayakawa M, Kushimoto S, Shiraishi A, Kato H, Sasaki J, Ogura H, Matauoka T, Uejima T, Morimura N, Ishikura H, Hagiwara A, Takeda M, Tarabrin O, Shcherbakow S, Gavrychenko D, Mazurenko G, Ivanova V, Chystikov O, Plourde C, Lessard J, Chauny J, Daoust R, Shcherbakow S, Tarabrin O, Gavrychenko D, Mazurenko G, Chystikov O, Vakalos A, Avramidis V, Kropman L, In het Panhuis L, Konings J, Huskens D, Schurgers E, Roest M, De Laat B, Lance M, Durila M, Lukas P, Astraverkhava M, Jonas J, Budnik I, Shenkman B, Hayami H, Koide Y, Goto T, Iqbal R, Alhamdi Y, Venugopal N, Abrams S, Downey C, Toh CH, Welters ID, Bombay VB, Chauny JM, Daoust RD, Lessard JL, Marquis MM, Paquet JP, Siemens K, Sangaran D, Hunt BJ, Durward A, Nyman A, Murdoch IA, Tibby SM, Ampatzidou F, Moisidou D, Dalampini E, Nastou M, Vasilarou E, Kalaizi V, Chatzikostenoglou H, Drossos G, Spadaro S, Fogagnolo A, Fiore T, Schiavi A, Fontana V, Taccone F, Volta C, Chochliourou E, Volakli E, Violaki A, Samkinidou E, Evlavis G, Panagiotidou V, Sdougka M, Mothukuri R, Battle C, Guy K, Mills G, Evans P, Wijesuriya J, Keogh S, Docherty A, O’Donnell R, Brunskill S, Trivella M, Doree C, Holst L, Parker M, Gregersen M, Almeida J, Walsh T, Stanworth S, Moravcova S, Mansell J, Rogers A, Smith RA, Hamilton-Davies C, Omar A, Allam M, Bilala O, Kindawi A, Ewila H, Ampatzidou F, Moisidou D, Nastou M, Dalampini E, Malamas A, Vasilarou E, Drossos G, Ferreira G, Caldas J, Fukushima J, Osawa EA, Arita E, Camara L, Zeferino S, Jardim J, Gaioto F, Dallan L, Jatene FB, Kalil Filho R, Galas F, Hajjar LA, Mitaka C, Ohnuma T, Murayama T, Kunimoto F, Nagashima M, Takei T, Tomita M, Omar A, Mahmoud K, Hanoura S, Sudarsanan S, Sivadasan P, Othamn H, Shouman Y, Singh R, Al Khulaifi A, Mandel I, Mikheev S, Suhodolo I, Kiselev V, Svirko Y, Podoksenov Y, Jenkins SA, Griffin R, Tovar Doncel MS, Lima A, Aldecoa C, Ince C, Taha A, Shafie A, Mostafa M, Syed N, Hon H, Righetti F, Colombaroli E, Castellano G, Righetti F, Colombaroli E, Hravnak M, Chen LC, Dubrawski AD, Clermont GC, Pinsky MR, Gonzalez S, Macias D, Acosta J, Jimenez P, Loza A, Lesmes A, Lucena F, Leon C, Tovar Doncel MS, Ince C, Aldecoa C, Lima A, Bastide M, Richecoeur J, Frenoy E, Lemaire C, Sauneuf B, Tamion F, Nseir S, Du Cheyron D, Dupont H, Maizel J, Shaban M, Kolko R, Salahuddin N, Sharshir M, AbuRageila M, AlHussain A, Mercado P, Maizel J, Kontar L, Titeca D, Brazier F, Riviere A, Joris M, Soupison T, De Cagny B, Slama M, Wagner J, Körner A, Kubik M, Kluge S, Reuter D, Saugel B, Colombaroli E, Righetti F, Castellano G, Tran T, De Bels D, Cudia A, Strachinaru M, Ghottignies P, Devriendt J, Pierrakos C, Martínez González Ó, Blancas R, Luján J, Ballesteros D, Martínez Díaz C, Núñez A, Martín Parra C, López Matamala B, Alonso Fernández M, Chana M, Huber W, Eckmann M, Elkmann F, Gruber A, Klein I, Schmid RM, Lahmer T, Moller PW, Sondergaard S, Jakob SM, Takala J, Berger D, Bastoni D, Aya H, Toscani L, Pigozzi L, Rhodes A, Cecconi M, Ostrowska C, Aya H, Abbas A, Mellinghoff J, Ryan C, Dawson D, Rhodes A, Cecconi M, Cronhjort M, Wall O, Nyberg E, Zeng R, Svensen C, Mårtensson J, Joelsson-Alm E, Aguilar Arzapalo M, Barradas L, Lopez V, Cetina M, Parenti N, Palazzi C, Amidei LA, Borrelli FB, Campanale SC, Tagliazucchi FT, Sedoni GS, Lucchesi DL, Carella EC, Luciani AL, Mackovic M, Maric N, Bakula M, Aya H, Rhodes A, Grounds RM, Fletcher N, Cecconi M, Avard B, Zhang P, Mezidi M, Charbit J, Ould-Chikh M, Deras P, Maury C, Martinez O, Capdevila X, Hou P, Linde-Zwirble WZ, Douglas ID, Shapiro NS, Ben Souissi A, Mezghani I, Ben Aicha Y, Kamoun S, Laribi B, Jeribi B, Riahi A, Mebazaa MS, Pereira C, Marinho R, Antunes R, Marinho A, Crivits M, Raes M, Decruyenaere J, Hoste E, Bagin V, Rudnov V, Savitsky A, Astafyeva M, Korobko I, Vein V, Kampmeier T, Arnemann P, Hessler M, Wald A, Bockbreder K, Morelli A, Van Aken H, Rehberg S, Ertmer C, Arnemann P, Hessler M, Kampmeier T, Rehberg S, Van Aken H, Ince C, Ertmer C, Reddy S, Bailey M, Beasley R, Bellomo R, Mackle D, Psirides A, Young P, Reddy S, Bailey M, Beasley R, Bellomo R, Mackle D, Young P, Venkatesh H, Ramachandran S, Basu A, Nair H, Egan S, Bates J, Oliveira S, Rangel Neto NR, Reis FQ, Lee CP, Lin XL, Choong C, Eu KM, Sim WY, Tee KS, Pau J, Abisheganaden J, Maas K, De Geus H, Lafuente E, Marinho R, Moura J, Antunes R, Marinho A, Doris TE, Monkhouse D, Shipley T, Kardasz S, Gonzalez I, Stads S, Groeneveld AJ, Elsayed I, Ward N, Tridente A, Raithatha A, Steuber A, Pelletier C, Schroeder S, Michael E, Slowinski T, Kindgen-Milles D, Ghabina S, Turani F, Belli A, Busatti S, Barettin G, Candidi F, Gargano F, Barchetta R, Falco M, Demirkiran O, Kosuk M, Bozbay S, Weber V, Hartmann J, Harm S, Linsberger I, Eichhorn T, Valicek G, Miestinger G, Hoermann C, Faenza S, Ricci D, Mancini E, Gemelli C, Cuoghi A, Magnani S, Atti M, Laddomada T, Doronzio A, Balicco B, Gruda MC, O’Sullivan P, Dan VP, Guliashvili T, Scheirer A, Golobish TD, Capponi VJ, Chan PP, Kogelmann K, Drüner M, Jarczak D, Turani F, Belli AB, Martni SM, Cotticelli VC, Mounajergi F, Barchetta R, Morimoto S, Ishikura H, Hussain I, Salahuddin N, Nadeem A, Ghorab K, Maghrabi K, Kloesel SK, Goldfuss C, Stieglitz A, Stieglitz AS, Krstevska L, Albuszies G, Aguilar Arzapalo M, Barradas L, Lopez V, Escalante A, Jimmy G, Cetina M, Izawa J, Iwami T, Uchino S, Takinami M, Kitamura T, Kawamura T, Powell-Tuck JG, Crichton S, Raimundo M, Camporota L, Wyncoll D, Ostermann M, Hana A, De Geus HR, De Geus HR, Hana A, Aydogdu M, Boyaci N, Yuksel S, Gursel G, Cayci Sivri AB, Meza-Márquez J, Nava-López J, Carrillo-Esper R, Dardashti A, Grubb A, Maizel J, Wetzstein M, Titeca D, Kontar L, Brazier F, De Cagny B, Riviere A, Soupison T, Joris M, Slama M, Peters E, Njimi H, Pickkers P, Vincent JL, Waraich M, Doyle J, Samuels T, Forni L, Desai N, Baumber R, Gunning P, Sell A, Lin S, Torrence H, O’Dwyer M, Kirwan C, Prowle J, Kim T, O’Connor ME, Hewson RW, Kirwan CJ, Pearse RM, Prowle J, Hanoura S, Omar A, Othamn H, Sudarsanan S, Allam M, Maksoud M, Singh R, Al Khulaifi A, O’Connor ME, Hewson RW, Kirwan CJ, Pearse RM, Prowle J, Uzundere O, Memis D, Ýnal M, Gultekin A, Turan N, Aydin MA, Basar H, Sencan I, Kapuagasi A, Ozturk M, Uzundurukan Z, Gokmen D, Ozcan A, Kaymak C, Artemenko VA, Budnyuk A, Pugh R, Bhandari S, Mauri T, Turrini C, Langer T, Taccone P, Volta CA, Marenghi C, Gattinoni L, Pesenti A, Sweeney L, O’Sullivan A, Kelly P, Mukeria E, MacLoughlin R, Pfeffer M, Thomas JT, Bregman GB, Karp GK, Kishinevsky EK, Stavi DS, Adi NA, Poropat T, Knafelj R, Llopart E, Batlle M, De Haro C, Mesquida J, Artigas A, Pavlovic D, Lewerentz L, Spassov A, Schneider R, De Smet S, De Raedt S, Derom E, Depuydt P, Oeyen S, Benoit D, Decruyenaere J, Gobatto A, Besen B, Tierno P, Melro L, Mendes P, Cadamuro F, Park M, Malbouisson LM, Civantos BC, Lopez JL, Robles A, Figueira J, Yus S, Garcia A, Oglinda A, Ciobanu G, Oglinda C, Schirca L, Sertinean T, Lupu V, Kelly P, O’Sullivan A, Sweeney L, MacLoughlin R, O’Sullivan A, Kelly P, Sweeney L, Mukeria E, Wolny M, MacLoughlin R, Pagano A, Numis F, Visone G, Saldamarco L, Russo T, Porta G, Paladino F, Bell C, Liu J, Debacker J, Lee C, Tamberg E, Campbell V, Mehta S, Silva-Pinto A, Sarmento A, Santos L, Kara Ý, Yýldýrým F, Zerman A, Güllü Z, Boyacý N, Basarýk Aydogan B, Gaygýsýz Ü, Gönderen K, Arýk G, Turkoglu M, Aydogdu M, Aygencel G, Ülger Z, Gursel G, Boyacý N, Isýkdogan Z, Özdedeoglu Ö, Güllü Z, Badoglu M, Gaygýsýz U, Aydogdu M, Gursel G, Kongpolprom N, Sittipunt C, Eden A, Kokhanovsky Y, Bursztein – De Myttenaere S, Pizov R, Neilans L, MacIntyre N, Radosevich M, Wanta B, Weber V, Meyer T, Smischney N, Brown D, Diedrich D, Fuller A, McLindon P, Sim K, Shoaeir M, Noeam K, Mahrous A, Matsa R, Ali A, Dridi C, Koubaji S, Kamoun S, Haddad F, Ben Souissi A, Laribi B, Riahi A, Mebazaa MS, Pérez-Calatayud A, Carrillo-Esper R, Zepeda-Mendoza A, Diaz-Carrillo M, Arch-Tirado E, Carbognin S, Pelacani L, Zannoni F, Agnoli A, Gagliardi G, Cho R, Adams A, Lunos S, Ambur S, Shapiro R, Prekker M, Thijssen M, Janssen L, Foudraine N, Voscopoulos CJ, Freeman J, Voscopoulos CJ, Freeman J, George E, Voscopoulos CJ, Eversole D, Freeman J, George E, Muttini S, Bigi R, Villani G, Patroniti N, Williams G, Voscopoulos CJ, Freeman J, George E, Waldmann A, Böhm S, Windisch W, Strassmann S, Karagiannidis C, Waldmann A, Böhm S, Windisch W, Strassmann S, Karagiannidis C, Karagiannidis CK, Waldmann AW, Böhm SB, Strassmann S, Windisch WW, Persson P, Lundin S, Stenqvist O, Porta G, Numis F, Serra CS, Pagano AP, Masarone MM, Rinaldi LR, Amelia AA, Fascione MF, Adinolfi LA, Ruggiero ER, Asota F, O’Rourke K, Ranjan S, Morgan P, DeBacker JW, Tamberg E, O’Neill L, Munshi L, Burry L, Fan E, Mehta S, Poo S, Mahendran K, Fowles J, Gerrard C, Vuylsteke A, Loveridge R, Chaddock C, Patel S, Kakar V, Willars C, Hurst T, Park C, Best T, Vercueil A, Auzinger G, Borgman A, Proudfoot AG, Grins E, Emiley KE, Schuitema J, Fitch SJ, Marco G, Sturgill J, Dickinson MG, Strueber M, Khaghani A, Wilton P, Jovinge SM, Sampson C, Harris-Fox S, Cove ME, Vu LH, Sen A, Federspiel WJ, Kellum JA, Mazo Torre C, Riera J, Ramirez S, Borgatta B, Lagunes L, Rello J, Kuzovlev AK, Moroz V, Goloubev A, Polovnikov S, Nenchuk S, Karavana V, Glynos C, Asimakos A, Pappas K, Vrettou C, Magkou M, Ischaki E, Stathopoulos G, Zakynthinos S, Spadaro S, Kozhevnikova I, Dalla Corte F, Grasso S, Casolari P, Caramori G, Volta C, Andrianjafiarinoa T, Randriamandrato T, Rajaonera T, El-Dash S, Costa ELV, Tucci MR, Leleu F, Kontar L, De Cagny B, Brazier F, Titeca D, Bacari-Risal G, Maizel J, Amato M, Slama M, Mercado P, Maizel J, Kontar L, Titeca D, Brazier F, Riviere A, Joris M, Soupison T, De Cagny B, El Dash S, Slama M, Remmington, Fischer A, Squire S, Boichat M, Honzawa H, Yasuda H, Adati T, Suzaki S, Horibe M, Sasaki M, Sanui M, Marinho R, Daniel J, Miranda H, Marinho A, Milinis K, Cooper M, Williams GR, McCarron E, Simants S, Patanwala I, Welters I, Su Y, Fernández Villanueva J, Fernández Garda R, López Lago A, Rodríguez Ruíz E, Hernández Vaquero R, Tomé Martínez de Rituerto S, Varo Pérez E, Lefel N, Schaap F, Bergmans D, Olde Damink S, Van de Poll M, Tizard K, Lister C, Poole L, Ringaitiene D, Gineityte D, Vicka V, Norkiene I, Sipylaite J, O’Loughlin A, Maraj V, Dowling J, Velasco MB, Dalcomune DM, Dias EB, Fernandes SL, Oshima T, Graf S, Heidegger C, Genton L, Karsegard V, Dupertuis Y, Pichard C, Friedli N, Stanga Z, Mueller B, Schuetz P, Vandersteen L, Stessel B, Evers S, Van Assche A, Jamaer L, Dubois J, Marinho R, Castro H, Moura J, Valente J, Martins P, Casteloes P, Magalhaes C, Cabral S, Santos M, Oliveira B, Salgueiro A, Marinho A, Marinho R, Santos M, Lafuente E, Castro H, Cabral S, Moura J, Martins P, Oliveira B, Salgueiro A, Duarte S, Castro S, Melo M, Casteloes P, Marinho A, Gray S, Maipang K, Bhurayanontachai R, Grädel LG, Schütz P, Langlois P, Manzanares W, Tincu R, Cobilinschi C, Tomescu D, Ghiorghiu Z, Macovei R, Manzanares W, Langlois P, Lemieux M, Elke G, Bloos F, Reinhart K, Heyland D, Langlois P, Lemieux M, Aramendi I, Heyland D, Manzanares W, Su Y, Marinho R, Babo N, Marinho A, Hoshino M, Haraguchi Y, Kajiwara S, Mitsuhashi T, Tsubata T, Aida M, Rattanapraphat T, Bhurayanontachai R, Kongkamol C, Khwannimit B, Marinho R, Santos M, Castro H, Lafuente E, Salgueiro A, Cabral S, Martins P, Moura J, Oliveira B, Melo M, Xavier B, Valente J, Magalhaes C, Casteloes P, Marinho A, Moisidou D, Ampatzidou F, Koutsogiannidis C, Moschopoulou M, Drossos G, Taskin G, Çakir M, Güler AK, Taskin A, Öcal N, Özer S, Yamanel L, Wong JM, Fitton C, Anwar S, Stacey S, Aggou M, Fyntanidou B, Patsatzakis S, Oloktsidou E, Lolakos K, Papapostolou E, Grosomanidis V, Suda S, Ikeda T, Ono S, Ueno T, Izutani Y, Gaudry S, Desailly V, Pasquier P, Brun PB, Tesnieres AT, Ricard JD, Dreyfuss D, Mignon A, White JC, Molokhia A, Dean A, Stilwell A, Friedlaender G, Peters M, Stipulante S, Delfosse A, Donneau AF, Ghuysen A, Feldmann C, Freitag D, Dersch W, Irqsusi M, Eschbach D, Steinfeldt T, Wulf H, Wiesmann T, Kongpolprom N, Cholkraisuwat J, Beitland S, Nakstad E, Stær-Jensen H, Drægni T, Andersen G, Jacobsen D, Brunborg C, Waldum-Grevbo B, Sunde K, Hoyland K, Pandit D, Hayakawa K, Oloktsidou E, Kotzampassi K, Fyntanidou B, Patsatzakis S, Loukipoudi L, Doumaki E, Grosomanidis V, Yasuda H, Admiraal MM, Van Assen M, Van Putten MJ, Tjepkema-Cloostermans M, Van Rootselaar AF, Horn J, Ragusa F, Marudi A, Baroni S, Gaspari A, Bertellini E, Taha A, Abdullah T, Abdel Monem S, Alcorn S, McNeill S, Russell S, Eertmans W, Genbrugge C, Meex I, Dens J, Jans F, De Deyne C, Cholkraisuwat J, Kongpolprom N, Avard B, Burns R, Patarchi A, Spina T, Tanaka H, Otani N, Ode S, Ishimatsu S, Cho J, Moon JB, Park CW, Ohk TG, Shin MC, Won MH, Dakova S, Ramsheva Z, Ramshev K, Cho J, Moon JB, Park CW, Ohk TG, Shin MC, Cho J, Moon JB, Park CW, Ohk TG, Shin MC, Marudi A, Baroni S, Gaspari A, Bertellini E, Orhun G, Senturk E, Ozcan PE, Sencer S, Ulusoy C, Tuzun E, Esen F, Tincu R, Cobilinschi C, Tomescu D, Ghiorghiu Z, Macovei R, Van Assen M, Admiraal MM, Van Putten MJ, Tjepkema-Cloostermans M, Van Rootselaar AF, Horn J, Fallenius M, Skrifvars MB, Reinikainen M, Bendel S, Raj R, Abu-Habsa M, Hymers C, Borowska A, Sivadhas H, Sahiba S, Perkins S, Rubio J, Rubio JA, Sierra R, English S, Chasse M, Turgeon A, Lauzier F, Griesdale D, Garland A, Fergusson D, Zarychanski R, Tinmouth A, Van Walraven C, Montroy K, Ziegler J, Dupont Chouinard R, Carignan R, Dhaliwal A, Lum C, Sinclair J, Pagliarello G, McIntyre L, English S, Chasse M, Turgeon A, Lauzier F, Griesdale D, Garland A, Fergusson D, Zarychanski R, Tinmouth A, Van Walraven C, Montroy K, Ziegler J, Dupont Chouinard R, Carignan R, Dhaliwal A, Lum C, Sinclair J, Pagliarello G, McIntyre L, Groza T, Moreau N, Castanares-Zapatero D, Hantson P, Carbonara M, Ortolano F, Zoerle T, Magnoni S, Pifferi S, Conte V, Stocchetti N, Carteron L, Suys T, Patet C, Quintard H, Oddo M, Rubio JA, Rubio J, Sierra R, Spatenkova V, Pokorna E, Suchomel P, Ebert N, Jancik J, Rhodes H, Bylinski T, Hawthorne C, Shaw M, Piper I, Kinsella J, Kink AK, Rätsep IR, Boutin A, Moore L, Chasse M, Zarychanski R, Lauzier F, English S, McIntyre L, Lacroix J, Griesdale D, Lessard-Bonaventure P, Turgeon AF, Boutin A, Moore L, Green R, Lessard-Bonaventure P, Erdogan M, Butler M, Lauzier F, Chasse M, English S, McIntyre L, Zarychanski R, Lacroix J, Griesdale D, Desjardins P, Fergusson DA, Turgeon AF, Goncalves B, Vidal B, Valdez C, Rodrigues AC, Miguez L, Moralez G, Hong T, Kutz A, Hausfater P, Amin D, Struja T, Haubitz S, Huber A, Mueller B, Schuetz P, Brown T, Collinson J, Pritchett C, Slade T, Le Guen M, Hellings S, Ramsaran R, Alsheikhly A, Abe T, Kanapeckaite L, Abu-Habsa M, Bahl R, Russell MQ, Real KJ, Abu-Habsa M, Lyon RM, Oveland NP, Penketh J, Mcdonald M, Kelly F, Alfafi M, Alsolamy S, Almutairi W, Alotaibi B, Van den Berg AE, Schriel Y, Dawson L, Meynaar IA, Talaie H, Silva D, Fernandes S, Gouveia J, Santos Silva J, Foley J, Kaskovagheorgescu A, Evoy D, Cronin J, Ryan J, Huck M, Hoffmann C, Renner J, Laitselart P, Donat N, Cirodde A, Schaal JV, Masson Y, Nau A, Leclerc T, Howarth O, Davenport K, Jeanrenaud P, Raftery S, MacTavish P, Devine H, McPeake J, Daniel M, Kinsella J, Quasim T, Alrabiee S, Alrashid A, Alsolamy S, Gundogan O, Bor C, Akýn Korhan E, Demirag K, Uyar M, Frame F, Ashton C, Bergstrom Niska L, Dilokpattanamongkol P, Suansanae T, Suthisisang C, Morakul S, Karnjanarachata C, Tangsujaritvijit V, Mahmood S, Al Thani H, Almenyar A, Vakalos A, Avramidis V, Sharvill R, Penketh J, Morton SE, Chiew YS, Pretty C, Chase JG, Shaw GM, Knafelj R, Kordis P, Patel S, Grover V, Kuchyn I, Bielka K, Aidoni Z, Grosomanidis V, Kotzampassi K, Stavrou G, Fyntanidou B, Patsatzakis S, Skourtis C, Lee SD, Williams K, Weltes ID, Berhane S, Arrowsmith C, Peters C, Robert S, Caldas J, Panerai RB, Robinson TG, Camara L, Ferreira G, Borg-Seng-Shu E, De Lima Oliveira M, Mian NC, Santos L, Nogueira R, Zeferino SP, Jacobsen Teixeira M, Galas F, Hajjar LA, Killeen P, McPhail M, Bernal W, Maggs J, Wendon J, Hughes T, Taniguchi LU, Siqueira EM, Vieira Jr JM, Azevedo LC, Ahmad AN, Abu-Habsa M, Bahl R, Helme E, Hadfield S, Loveridge R, Shak J, Senver C, Howard-Griffin R, Wacharasint P, Fuengfoo P, Sukcharoen N, Rangsin R, Sbiti-Rohr D, Schuetz P, Na H, Song S, Lee S, Jeong E, Lee K, Cooper M, Milinis K, Williams G, McCarron E, Simants S, Patanwala I, Welters ID, Zoumpelouli E, Volakli EA, Chrysohoidou V, Georgiou S, Charisopoulou K, Kotzapanagiotou E, Panagiotidou V, Manavidou K, Stathi Z, Sdougka M, Salahuddin N, AlGhamdi B, Marashly Q, Zaza K, Sharshir M, Khurshid M, Ali Z, Malgapo M, Jamil M, Shafquat A, Shoukri M, Hijazi M, Abe T, Uchino S, Takinami M, Rangel Neto NR, Oliveira S, Reis FQ, Rocha FA, Moralez G, Ebecken K, Rabello LS, Lima MF, Hatum R, De Marco FV, Alves A, Pinto JE, Godoy M, Brasil PE, Bozza FA, Salluh JI, Soares M, Krinsley J, Kang G, Perry J, Hines H, Wilkinson KM, Tordoff C, Sloan B, Bellamy MC, Moreira E, Verga F, Barbato M, Burghi G, Soares M, Silva UV, Azevedo LC, Torelly AP, Kahn JM, Angus DC, Knibel MF, Brasil PE, Bozza FA, Salluh JI, Velasco MB, Dalcomune DM, Marshall R, Gilpin T, Tridente A, Raithatha A, Mota D, Loureiro B, Dias J, Afonso O, Coelho F, Martins A, Faria F, Al-Dorzi H, Al Orainni H, AlEid F, Tlaygeh H, Itani A, Hejazi A, Arabi Y, Gaudry S, Messika J, Ricard JD, Guillo S, Pasquet B, Dubief E, Dreyfuss D, Tubach F, Battle C, James K, Temblett P, Davies L, Battle C, Lynch C, Pereira S, Cavaco S, Fernandes J, Moreira I, Almeida E, Seabra Pereira F, Malheiro M, Cardoso F, Aragão I, Cardoso T, Fister M, Knafelj R, Muraray Govind P, Brahmananda Reddy N, Pratheema R, Arul ED, Devachandran J, Velasco MB, Dalcomune DM, Knafelj R, Fister M, Chin-Yee N, D’Egidio G, Thavorn K, Heyland D, Kyeremanteng K, Murchison AG, Swalwell K, Mandeville J, Stott D, Guerreiro I, Devine H, MacTavish P, McPeake J, Quasim T, Kinsella J, Daniel M, Goossens C, Marques MB, Derde S, Vander Perre S, Dufour T, Thiessen SE, Güiza F, Janssens T, Hermans G, Vanhorebeek I, De Bock K, Van den Berghe G, Langouche L, Devine H, MacTavish P, Quasim T, Kinsella J, Daniel M, McPeake J, Miles B, Madden S, Devine H, Weiler M, Marques P, Rodrigues C, Boeira M, Brenner K, Leães C, Machado A, Townsend R, Andrade J, MacTavish P, McPeake J, Devine H, Kinsella J, Daniel M, Kishore R, Fenlon C, Quasim T, Fiks T, Ruijter A, Te Raa M, Spronk P, Chiew YS, Docherty P, Dickson J, Moltchanova E, Scarrot C, Pretty C, Shaw GM, Chase JG, Hall T, Ngu WC, Jack JM, Morgan P, Avard B, Pavli A, Gee X, Bor C, Akin Korhan E, Demirag K, Uyar M, Shirazy M, Fayed A, Gupta S, Kaushal A, Dewan S, Varma A, Ghosh E, Yang L, Eshelman L, Lord B, Carlson E, Helme E, Broderick R, Hadfield S, Loveridge R, Ramos J, Forte D, Yang F, Hou P, Dudziak J, Feeney J, Wilkinson K, Bauchmuller K, Shuker K, Faulds M, Raithatha A, Bryden D, England L, Bolton N, Tridente A, Bauchmuller K, Shuker K, Tridente A, Faulds M, Matheson A, Gaynor J, Bryden D, ᅟ SSYHRC, Ramos J, Peroni B, Daglius-Dias R, Miranda L, Cohen C, Carvalho C, Velasco I, Forte D, Kelly JM, Neill A, Rubenfeld G, Masson N, Min A, Boezeman E, Hofhuis J, Hovingh A, De Vries R, Spronk P, Cabral-Campello G, Aragão I, Cardoso T, Van Mol M, Nijkamp M, Kompanje E, Ostrowski P, Omar A, Kiss K, Köves B, Csernus V, Molnár Z, Hoydonckx Y, Vanwing S, Stessel B, Van Assche A, Jamaer L, Dubois J, Medo V, Galvez R, Miranda JP, Stone C, Wigmore T, Arunan Y, Wheeler A, Bauchmuller K, Bryden D, Wong Y, Poi C, Gu C, Molmy P, Van Grunderbeeck N, Nigeon O, Lemyze M, Thevenin D, Mallat J, Ramos J, Correa M, Carvalho RT, Forte D, Fernandez A, McBride C, Koonthalloor E, Walsh C, Webber A, Ashe M, Smith K, Jeanrenaud P, Marudi A, Baroni S, Ragusa F, Bertellini E, Volakli EA, Chochliourou E, Dimitriadou M, Violaki A, Mantzafleri P, Samkinidou E, Vrani O, Arbouti A, Varsami T, Sdougka M, Bollen JA, Van Smaalen TC, De Jongh WC, Ten Hoopen MM, Ysebaert D, Van Heurn LW, Van Mook WN, Sim K, Fuller A, Roze des Ordons A, Couillard P, Doig C, Van Keer RV, Deschepper RD, Francke AF, Huyghens LH, Bilsen JB, Nyamaizi B, Dalrymple C, Molokhia A, Dobru A, Marrinan E, Ankuli A, Molokhia A, McPeake J, Struthers R, Crawford R, Devine H, Mactavish P, Quasim T, Morelli P, Degiovanangelo M, Lemos F, MArtinez V, Verga F, Cabrera J, Burghi G, Rutten A, Van Ieperen S, De Geer S, Van Vugt M, Der Kinderen E, Giannini A, Miccinesi G, Marchesi T, Prandi E. Erratum to: 36th International Symposium on Intensive Care and Emergency Medicine: Brussels, Belgium. 15-18 March 2016

[This corrects the article DOI: 10.1186/s13054-016-1208-6.].

Agonist and antagonist bind differently to 5-HT1A receptors during Alzheimer's disease: A post-mortem study with PET radiopharmaceuticals

PET imaging studies using 5-HT1A receptor radiotracers show a decreased density of this receptor in hippocampi of patients with Alzheimer's disease (AD) at advanced stages. However, current 5-HT1A receptor radiopharmaceuticals used in neuroimaging are antagonists, thought to bind to 5-HT1A receptors in different functional states (i.e., both the one which displays high affinity for agonists and is thought to mediate receptor activation, as well as the state which has low affinity for agonists). Comparing the PET imaging obtained using an agonist radiotracer, which binds selectively to functional receptors, with the PET imaging obtained using an antagonist radiotracer would therefore provide original information on 5-HT1A receptor impairment during AD. Quantitative autoradiography using [(18)F]F13640 and [(18)F]MPPF, a 5-HT1A agonist and antagonist, respectively, was measured in hippocampi of patients with AD (n = 25, at different Braak stages) and control subjects (n = 9). The neuronal density was measured in the same tissues by NeuN immunohistochemistry. The specific binding of both radiotracers was determined by addition of WAY-100635, a selective 5-HT1A receptor antagonist. The autoradiography distribution of both 5-HT1A PET radiotracers varied across hippocampus regions. The highest binding density was in the pyramidal layer of CA1. Incubation with Gpp(NH)p, a non-hydrolysable analogue of GTP, reduced significantly [(18)F]F13640 binding in hippocampal regions, confirming its preferential interaction with G-coupled receptors, and slightly increased [(18)F]MPPF binding. In the CA1 subfield, [(18)F]F13640 binding was significantly decreased at Braak stages I/II (-19%), Braak stages III/IV (-23%), and Braak stages V/VI (-36%) versus control. In contrast, [(18)F]MPPF binding was statistically reduced only at the most advanced Braak stages V/VI compared to control (-33%). Since [(18)F]F13640 and [(18)F]MPPF can be used in vivo in humans, this neuropharmacological paradigm supports testing the concept of functional imaging using agonist radiopharmaceuticals in future clinical studies.