The Clinical Challenge of Prosthetic Valve Endocarditis: JACC Focus Seminar 3/4

During the past 6 decades, there have been numerous changes in prosthetic valve endocarditis (PVE), currently affecting an older population and increasing in incidence in patients with transcatheter-implanted valves. Significant microbiologic (molecular biology) and imaging diagnostic (fluorine-18 fluorodeoxyglucose-positron emission tomography/computed tomography) advances have been incorporated into the 2023 Duke-International Society for Cardiovascular Infectious Diseases infective endocarditis diagnostic criteria, thus increasing the diagnostic sensitivity for PVE without sacrificing specificity in validation studies. PVE is a life-threatening disease requiring management by multidisciplinary endocarditis teams in cardiac centers to improve outcomes. Novel surgical options are now available, and an increasing set of patients may avoid surgical intervention despite indication. Selected patients may complete parenteral or oral antimicrobial treatment at home. Finally, patients with prosthetic valves implanted surgically or by the transcatheter approach are candidates for antibiotic prophylaxis before invasive dental procedures.

Comparative histologic features among liver biopsies with biliary-pattern injury and confirmed clinical diagnoses

Biliary-pattern injury in the liver (eg, duct injury, ductular reaction, cholestasis) can occur in several conditions, including primary biliary cholangitis (PBC), primary sclerosing cholangitis (PSC), large duct obstruction (LDO), and drug-induced liver injury (DILI). While the histologic changes in these conditions have been individually well described, distinguishing among them remains often challenging, particularly when biopsy samples are limited in size, robust clinical information is unavailable, and/or the pathologist does not feel confident in evaluating liver disease. This study evaluated histologic features that could aid the diagnosis of biliary-pattern injury on biopsy. We reviewed 121 liver biopsies from clinically confirmed cases of PBC, PSC, chronic LDO, or DILI for multiple clinical and histologic parameters. The rates of these histologic findings were then compared among different entities. Onion-skin fibrosis was seen in 14% of PSC in comparison to 0%, 5%, and 0% of PBC, DILI, and chronic LDO (P = 0.031). Florid duct lesions were identified in 21% of PBC compared to 2% of PSC and 0% of DILI and LDO (P = 0.0065). Similarly, 42% of PBC showed lobular granulomas, compared to 7% of PSC, 11% of DILI, and 33% of chronic LDO (P = 0.0001). Cholestasis was more commonly seen in DILI (42%) and chronic LDO (83%) than in PBC (4%) and PSC (16%) (P < 0.0001). Lobular chronic inflammation was found in a significantly higher percentage of PBC and LDO than of PSC and DILI (P = 0.0009). There were significantly fewer cases of PBC showing neutrophils in ductular reaction than PSC, DILI, and LDO (P = 0.0063). Histologic findings that can help suggest a diagnosis in liver biopsies with biliary-pattern injury include florid duct lesions, lobular granulomas, lack of neutrophils in ductular reaction, and lobular chronic inflammation in PBC; onion-skin fibrosis in PSC; cholestasis and feathery degeneration in DILI; and lobular granulomas, lobular chronic inflammation, cholestasis, and feathery degeneration in chronic LDO. These findings are likely most helpful when complicating factors interfere with biopsy interpretation.

Risk scores' performance and their impact on operative decision-making in left-sided endocarditis: a cohort study

The accuracy of contemporary risk scores in predicting perioperative mortality in infective endocarditis (IE) remains controversial. The aim is to evaluate the performance of existent mortality risk scores for cardiovascular surgery in IE and the impact on operability at high-risk thresholds. A single-center retrospective review of adult patients diagnosed with acute left-sided IE undergoing surgery from May 2014 to August 2019 (n = 142) was done. Individualized risk calculation was obtained according to the available mortality risk scores: EuroScore I and II, PALSUSE, Risk-E, Costa, De Feo-Cotrufo, AEPEI, STS-risk, STS-IE, APORTEI, and ICE-PCS scores. A cross-validation analysis was performed on the score with the best area under the curve (AUC). The 30-day survival was 96.5% (95%CI 91-98%). The score with worse area under the curve (AUC = 0.6) was the STS-IE score, while the higher was for the RISK-E score (AUC = 0.89). The AUC of the majority of risk scores suggested acceptable performance; however, statistically significant differences in expected versus observed mortalities were common. The cross-validation analysis showed that a large number of survivors (> 75%) would not have been operated if arbitrary high-risk threshold estimates had been used to deny surgery. The observed mortality in our cohort is significantly lower than is predicted by contemporary risk scores. Despite the reasonable numeric performance of the analyzed scores, their utility in judging the operability of a given patient remains questionable, as demonstrated in the cross-validation analysis. Future guidelines may advise that denial of surgery should only follow a highly experienced Endocarditis Team evaluation.

Forty-year trends in cardiac implantable electronic device (CIED) infective endocarditis (IE)

Background

Studies investigating cardiac implantable electronic device infective endocarditis (CIED-IE) epidemiological changes and prognosis over long periods of time are lacking.

Methods

Retrospective single cardiovascular surgery center cohort study of definite CIED-IE episodes between 1981–2020. A comparative analysis of two periods (1981–2000 vs 2001–2020) was conducted to analyze changes in epidemiology and outcome over time.

Results

One-hundred and thirty-eight CIED-IE episodes were diagnosed: 25 (18%) first period and 113 (82%) second. CIED-IE was 4.5 times more frequent in the second period, especially in implantable cardiac defibrillators. Age (63 [53-70] vs 71 [63–76] years, P < .01), comorbidities (CCI 3.0 [2–4] vs 4.5 [3–6], P > .01), nosocomial infections (4% vs 15.9%, P = .02) and transfers from other centers (8% vs 41.6%, P < .01) were significantly more frequent in the second period, as were methicillin-resistant coagulase-negative staphylococcal (MR-CoNS) (0% vs 13.3%, P < .01) and Enterococcus spp. (0% vs 5.3%, P = .01) infections, pulmonary embolism (0% vs 10.6%, P < .01) and heart failure (12% vs 28.3%, p < .01). Second period surgery rates were lower (96% vs 87.6%, P = .09), and there were no differences in in-hospital (20% vs 11.5%, P = .11) and one-year mortalities (24% vs 15%, P = .33), or relapses (8% vs 5.3%, P = 0.65). Multivariate analysis showed Charlson index (hazard ratios [95% confidence intervals]; 1.5 [1.16–1.94]) and septic shock (23.09 [4.57–116.67]) were associated with a worse prognosis, whereas device removal (0.11 [.02–.57]), transfers (0.13 [.02–0.95]), and second-period diagnosis (0.13 [.02–.71]) were associated with better one-year outcomes.

Conclusions

CIED-IE episodes increased more than four-fold during last 40 years. Despite CIED-IE involved an older population with more comorbidities, antibiotic-resistant MR-CoNS, and complex devices, one-year survival improved.

Cardiac telerrehabilitation: a safe and effective alternative in patients with coronary artery disease

Funding Acknowledgements

Type of funding sources: Other. Main funding source(s): Ferrer Internaciona Groupl, S.A

Background

Center-based cardiac rehabilitation programs (CRP) have shown to reduce morbidity and mortality after an ischemic cardiac event, but their vastly underutilized. Home-based CRP seems to improve patient’s adherence, but there is still scarce evidence, especially in elderly patients and women.

Purpose

To develop a holistic home-based CRP for ischemic heart disease patients and evaluate its safety and impact on functional capacity, adherence to a heart-healthy lifestyle and quality of life.

Methods

The 8-week home-based CRP will include 60 patients (50% women) with no age limit who have suffered an acute myocardial infarction in the previous 3 months, with LVEF ≥40% and a tablet/mobile device. The CRP (Picture 1) includes 3 weekly exercise sessions combining tailored aerobic and strength training and 1 weekly educational session focused on lifestyle habits, therapeutic adherence, and patient empowerment.

Results

Between January and October 2021, 56 patients were included: 2 were rejected for presenting ventricular arrhythmias in the initial stress test and 4 due to technological barrier; 14 patients are currently performing the CRP. The preliminary results from the 36 patients who have completed the CRP show a significant increase in functional capacity, muscle strength, weekly training volume, adherence to Mediterranean diet, emotional state (anxiety) and quality of life (Picture 2). There have been no complications and patient’s adherence has been excellent for both exercise (85%) and educational (80%) sessions.

Conclusion

A holistic telematic CRP dedicated to patients after an ischemic cardiac event, including patients of both gender and of no age-limit, seems to be a feasible, safe and effective in improving maximal aerobic capacity, weekly training volume, muscle strength, quality of life, compliance with the Mediterranean diet and emotional state.

ADENI-UCI study: Analysis of non-income decisions in ICU as a measure of limitation of life support treatments

OBJECTIVE

To analyze the variables associated with ICU refusal decisions as a life support treatment limitation measure.

DESIGN

Prospective, multicentrico.

SCOPE

62 ICU from Spain between February 2018 and March 2019.

PATIENTS

Over 18 years of age who were denied entry into ICU as a life support treatment limitation measure.

INTERVENTIONS

None.

MAIN INTEREST VARIABLES

Patient comorities, functional situation as measured by the KNAUS and Karnosfky scale; predicted scales of Lee and Charlson; severity of the sick person measured by the APACHE II and SOFA scales, which justifies the decision-making, a person to whom the information is transmitted; date of discharge or in-hospital death, destination for hospital discharge.

RESULTS

A total of 2312 non-income decisions were recorded as an LTSV measure of which 2284 were analyzed. The main reason for consultation was respiratory failure (1080 [47.29%]). The poor estimated quality of life of the sick (1417 [62.04%]), the presence of a severe chronic disease (1367 [59.85%]) and the prior functional limitation of patients (1270 [55.60%]) were the main reasons for denying admission. The in-hospital mortality rate was 60.33%. The futility of treatment was found as a risk factor associated with mortality (OR: 3.23; IC95%: 2.62-3.99).

CONCLUSIONS

Decisions to limit ICU entry as an LTSV measure are based on the same reasons as decisions made within the ICU. The futility valued by the intensivist is adequately related to the final result of death.

Long-term cardiac assessment in a sample of adolescent-onset anorexia nervosa

BACKGROUND

High mortality rates have been reported in patients with anorexia nervosa, mainly due to cardiovascular alterations. The purpose of the present study was to assess cardiac structural and functional abnormalities some 20 years after initial treatment in a sample of adolescent-onset anorexia nervosa (A-AN) and to compare them with matched healthy controls (HC).

METHODS

A sample of 29 women diagnosed and treated for AN during adolescence (A-AN) were assessed more than 20 years later. A complete cardiac evaluation was carried out including an electrocardiogram (ECG) and a standard 2D echocardiography. Thirty matched HC were also assessed.

RESULTS

In the A-AN group, four subjects had a body mass index lower than 18.5 and met full DSM 5 criteria for AN at follow-up (Low-Weight group). They were compared with the rest of the sample (n = 25) who had normalized their weight (Normal-Weight group), though some still showed some eating disorder symptoms. Both groups were compared with the HC group. Subjects in the Low-Weight group presented statistically significant decreases in the left ventricular end-diastolic and left atrium dimensions and left ventricular mass in comparison with the Normal-Weight group and the HC. No other differences in cardiac parameters were found between groups.

CONCLUSIONS

Echocardiographic and ECG parameters of adults who had presented A-AN twenty years earlier and currently maintained normal weight were similar to those of HC who had never been treated or diagnosed with AN. Adult subjects with A-AN who still had low weight in the long term present certain cardiac abnormalities similar to those seen in short-lasting disease. More studies are needed to confirm these results in a larger sample.

A Pilot Gene Expression and Histopathologic Analysis of Tracheal Resections in Tracheobronchomalacia

BACKGROUND

The airway structures and mRNA expression of genes that regulate airway inflammation and remodeling may be altered in the trachea of patients with tracheobronchomalacia (TBM).

METHODS

Fourteen tracheal specimens from 2005-to-2018 were used in this study. Surgical resection specimens from patients with TBM and tracheal stenosis (TS) were compared to control tracheal specimens obtained from autopsy cases. We investigated the mRNA expression of genes encoding fibroblast growth factor (FGF), binding protein 2 (FGFBP2), FGF receptor R3 (FGFR3), interleukin-1 beta (IL1β), tumor growth factor-beta 1 (TGFβ1), tissue inhibitor of metalloproteinases 1 (TIMP1), and intercellular adhesion molecule 1 (ICAM1), as well as established markers of airway inflammation including interferon-gamma (IFNγ) and tumor necrosis factor (TNF). The relative expression of target transcripts was assessed by qRT-PCR. A histological examination of the same resected airway specimens was performed on formalin-fixed paraffin embedded tissue sections.

RESULTS

FGFBP2 and FGFR3 showed higher expression in TBM compared to TS and control groups (p<0.05, p<0.01, respectively). Furthermore, both TGFβ1 and TIMP1 were elevated in TBM compared to controls (p<0.05). Conversely, ICAM1 was downregulated in TBM versus TS and controls (p<0.05). IL1β, IFNγ, and TNF were increased in TBM although did not achieve statistical significance. Histologically, compared to control airways, both TBM and TS demonstrated submucosal fibrotic changes, with TBM additionally demonstrating alterations in elastin fiber quality and density in the posterior membrane.

CONCLUSIONS

Significant changes in gene expression are observed in the tracheal walls of patients with TBM and TS compared to controls.

Argon Plasma Coagulation (APC) for the Treatment of Excessive Dynamic Airway Collapse (EDAC): An Animal Pilot Study

BACKGROUND

Surgical stabilization of the airway through tracheobronchoplasty (TBP) is the current treatment modality for patients with severe symptomatic excessive dynamic airway collapse. However, TBP is associated with increased morbidity and mortality. Bronchoscopic treatment of the posterior membrane using argon plasma coagulation (APC) may be a safer alternative to TBP in highly selected patients. This study aimed to evaluate the effect of APC in the tracheobronchial tree of a sheep animal model.

PATIENTS AND METHODS

Two adult sheep were used for this study. Under flexible bronchoscopy, the posterior tracheal membrane was treated with precise APC using different power settings. Chest computed tomography was done at 2 days and bronchoscopy was performed at 30 days following initial procedure, before euthanasia. The airways were assessed for the presence of treatment-related histopathologic changes along with expression of genes associated with fibrosis.

RESULTS

There was no perioperative or postoperative morbidity or mortality. Chest computed tomography showed no signs of pneumomediastinum or pneumothorax. Flexible bronchoscopy showed adequate tracheobronchial tissue healing process, independent of the power settings used. Histologic changes demonstrated an increased extent of fibroblastic collagen deposition in the treated posterior membrane when higher power settings were used. In a similar manner, APC treatment managed to activate fibrosis-associated gene transcription factors, with higher settings achieving a higher level of expression.

CONCLUSION

APC at high-power settings achieved higher levels of fibroblast collagen deposition at the posterior membrane and higher expression of fibrosis-associated gene transcription factors, when compared with lower settings.

Cloxacillin or fosfomycin plus daptomycin combinations are more active than cloxacillin monotherapy or combined with gentamicin against MSSA in a rabbit model of experimental endocarditis

BACKGROUND

In vitro and in vivo activity of daptomycin alone or plus either cloxacillin or fosfomycin compared with cloxacillin alone and cloxacillin plus gentamicin were evaluated in a rabbit model of MSSA experimental endocarditis (EE).

METHODS

Five MSSA strains were used in the in vitro time-kill studies at standard (105-106 cfu/mL) and high (108 cfu/mL) inocula. In the in vivo EE model, the following antibiotic combinations were evaluated: cloxacillin (2 g/4 h) alone or combined with gentamicin (1 mg/kg/8 h) or daptomycin (6 mg/kg once daily); and daptomycin (6 mg/kg/day) alone or combined with fosfomycin (2 g/6 h).

RESULTS

At standard and high inocula, daptomycin plus fosfomycin or cloxacillin were bactericidal against 4/5 and 5/5 strains, respectively, while cloxacillin plus gentamicin was bactericidal against 3/5 strains at standard inocula but against none at high inocula. Fosfomycin, cloxacillin, gentamicin and daptomycin MIC/MBCs of the MSSA-678 strain used in the EE model were: 8/64, 0.25/0.5, 0.25/0.5 and 1/8 mg/L, respectively. Adding gentamicin to cloxacillin significantly reduced bacterial density in vegetations compared with cloxacillin monotherapy (P = 0.026). Adding fosfomycin or cloxacillin to daptomycin [10/11 (93%) and 8/11 (73%), respectively] significantly improved the efficacy of daptomycin in sterilizing vegetations [0/11 (0%), P < 0.001 for both combinations] and showed better activity than cloxacillin alone [0/10 (0%), P < 0.001 for both combinations] and cloxacillin plus gentamicin [3/10 (30%), P = 0.086 for cloxacillin plus daptomycin and P = 0.008 for fosfomycin plus daptomycin]. No recovered isolates showed increased daptomycin MIC.

CONCLUSIONS

The addition of cloxacillin or fosfomycin to daptomycin is synergistic and rapidly bactericidal, showing better activity than cloxacillin plus gentamicin for treating MSSA EE, supporting their clinical use.

Pulmonary ridge coverage and device-related thrombosis after left atrial appendage occlusion

AIMS

The aim of this study was to evaluate the impact of pulmonary ridge (PR) coverage on both clinical and imaging follow-up outcomes in patients undergoing left atrial appendage occlusion (LAAO).

METHODS AND RESULTS

The study included consecutive patients with non-valvular atrial fibrillation who underwent LAAO with disc and lobe devices. Patients were classified into two groups according to the PR coverage. A total of 147 patients were included. Among these, the PR was covered in 109 (74%) and uncovered in 38 (26%). Successful implantation was achieved in 98.6%. No differences in procedural outcomes were observed between the groups. The rate of procedural major adverse events was 3% (only major bleedings and/or vascular access complications). No device embolisation, cardiac tamponade or in-hospital mortality was observed. After a mean follow-up of 1.77±2.2 years, the annualised ischaemic stroke and major bleeding rate was 1.3%/year and 6.5%/year, respectively, without differences between groups. At follow-up, patients with a covered PR presented a lower incidence of device-related thrombosis (DRT) (1%) than those with an uncovered PR (27%); p<0.001. In multivariable analysis, the presence of PR coverage emerged as an independent predictor of DRT.

CONCLUSIONS

Pulmonary ridge coverage was associated with a lower incidence of DRT after LAAO. Procedural and follow-up clinical outcomes did not differ between covered PR and uncovered PR patients.

ADENI-UCI Study: Analysis of non-income decisions in ICU as a measure of limitation of life support treatments

OBJECTIVE

To analyze the variables associated with ICU refusal decisions as a life support treatment limitation measure.

DESIGN

Prospective, multicentrico SCOPE: 62 ICU from Spain between February 2018 and March 2019.

PATIENTS

Over 18 years of age who were denied entry into ICU as a life support treatment limitation measure.

INTERVENTIONS

None.

MAIN INTEREST VARIABLES

Patient comorities, functional situation as measured by the KNAUS and Karnosfky scale; predicted scales of Lee and Charlson; severity of the sick person measured by the APACHE II and SOFA scales, which justifies the decision-making, a person to whom the information is transmitted; date of discharge or in-hospital death, destination for hospital discharge.

RESULTS

A total of 2312 non-income decisions were recorded as an LTSV measure of which 2284 were analyzed. The main reason for consultation was respiratory failure (1080 [47.29%]). The poor estimated quality of life of the sick (1417 [62.04%]), the presence of a severe chronic disease (1367 [59.85%]) and the prior functional limitation of patients (1270 [55.60%]) were the main reasons for denying admission. The in-hospital mortality rate was 60.33%. The futility of treatment was found as a risk factor associated with mortality (OR: 3.23; IC95%: 2.62-3.99).

CONCLUSIONS

Decisions to limit ICU entry as an LTSV measure are based on the same reasons as decisions made within the ICU. The futility valued by the intensivist is adequately related to the final result of death.

Aortic stiffness and distensibility in elite athletes: impact of discipline and gender

Background

Aortic remodeling in athletes is variable among sports disciplines with more ascending aorta (Asc Ao) dilatation in endurance (EAs) as compared to power athletes (PAs). Nevertheless, the impact of this differential remodeling on the Asc Ao functional properties is not well established. The aim of this study was to assess the distensibility and stiffness of the ascending aorta in endurance and power elite athletes in order to evaluate if this aortic remodeling implies functional changes.

Methods

119 elite athletes (61 EA and 58 PA, 49% female sex, mean age: 18.7±7.1 years) underwent standardized pre-participation screening with 12 lead ECG, transthoracic echocardiography and maximum stress test. Asc Ao diameter was measured from parasternal long axis views in 2D echocardiography. The aortic distensibility index (ADi) was calculated as 2 × (systolic Asc Ao diameter − diastolic Asc Ao diameter) / (diastolic Asc Ao diameter) × (pulse pressure) (cm–2 dyn–1 10–6). Aortic stiffness (AS) index was defined as Ln (systolic blood pressure/diastolic blood pressure) / (systolic Asc Ao diameter − diastolic Asc Ao diameter)/diastolic proximal Asc Ao diameter.

Results

Globally, EA presented larger AscAO, both in absolute and indexed values, than PA (28±3.0 vs 26±3.0cm, p&lt;0.001 and 16.4±1.5 vs 15.7±1.9cm, p&lt;0.05, while were no differences in AS or ADi) (Figure 1A). Nevertheless, ADi in male EAs was higher than in male PAs (ADi: 4.3±1.7 vs 3.2±1.3 cm2/dyn/10–6, p&lt;0.05) and AS was lower (AS: 4.7±1.7 vs 6.3±3.8, P&lt;0.005) (Figure 1B and 1C). Female athletes presented higher ADi (ADi: 4.7±1.9 vs 4.0±1.6 cm, p&lt;0.05) and a trend towards lower AS (4.8±2.9 vs 5.1±2.6, p: 0.4) than male athletes. There were no differences in AS or ADi between female EAs and PAs.

Conclusion

Male EAs showed an increased aortic distensibility with lower stiffness as compared to that observed in male PAs. This difference was not observed in female EAs and PAs, potentially due to better baseline distensibility with less room for improvement with endurance training.

Funding Acknowledgement

Type of funding source: None

Dynamique de l’excrétion virale chez les patients infectés par le SARS-CoV-2

Introduction

La durée de contagiosité d’un patient infecté par le SARS-CoV-2 n’est à ce jour pas encore clairement définie. Dans l’attente de nouvelles données, des recommandations sur les critères de levées d’isolement (précautions gouttelettes et contact), ont été émises par le Haut Conseil de santé publique. Ces recommandations se basent sur des critères cliniques et temporels et recommandent une durée totale d’isolement d’au moins 14 jours après le début des symptômes en population générale et d’au moins 24 jours chez les patients immunodéprimés. D’autres recommandations internationales (notamment celles de l’eCDC et des Chinoises) associent aux critères de levée d’isolement, une à deux PCR de contrôle sur écouvillons nasopharyngés. Notre établissement centralise depuis le début de l’épidémie les prélèvements pour recherche de SARS-CoV-2 par RT-PCR sur écouvillons nasopharyngés pour 7 établissements de santé. L’objectif de notre étude a été d’évaluer la proportion de patients gardant une PCR positive à SARS-CoV-2 au-delà de 24 jours après la première PCR positive.

Matériels et méthodes

Étude rétrospective incluant l’ensemble des patients ayant eu un dépistage par PCR nasopharyngée (3 mars–10 juin 2020) au sein des 7 établissements. Les données analysées ont inclus l’âge des patients, le délai de réalisation (en jours) entre 2 PCR, le service clinique.

Résultats

À la date du 10 juin, 3603 dépistages (dont 37 non-rendus pour problèmes techniques) ont été réalisés chez 3032 patients ; parmi ces patients, 348 ont eu plusieurs dépistages : 278 ont été dépistés deux fois, 47 trois fois, et 23 quatre fois ou plus. La répartition des patients gardant une PCR positive au moins 24 jours après la première était la suivante :

– 20 patients ont eu un dépistage de contrôle entre 24 et 29 jours après le premier dépistage : 1 patient était encore positif à j27 (5 %) ;

– 42 patients ont eu un dépistage de contrôle entre 30 et 41 jours : 8 étaient encore positifs (19 %) ;

– 34 patients ont eu un dépistage de contrôle après 42 jours : 3 étaient encore positifs (9 %).

Les 12 patients gardant une PCR positive au moins 24 jours après la première, avaient été hospitalisés, avaient une moyenne d’âge de 66 ans et 7 d’entre eux avaient un cancer sous-jacent ou avaient nécessité une prise en charge en réanimation.

Conclusion

Plus de 10 % des patients dépistés au moins 24 jours après le diagnostic microbiologique gardait une PCR nasopharyngée positive. Même si l’excrétion d’ARN viral n’équivaut pas directement à l’infectiosité, au vu des inconnues encore importantes sur le SARS-CoV-2, la levée précoce de l’isolement doit être réfléchie au cas par cas, en particulier pour les formes graves et les patients immunodéprimés.

Clinical impact of rapid susceptibility testing on MHR-SIR directly from blood cultures

BACKGROUND

In a previous study, we demonstrated that rapid antibiotic susceptibility tests (ASTs) can be performed directly on blood culture samples tested on Mueller-Hinton Rapid agar (MHR-SIR) with a time delay of 6-8 h.

OBJECTIVES

Using this rapid disc diffusion method, we analysed the clinical impact associated with rapid reporting of results in our hospital setting.

METHODS

All patients with bloodstream infections (BSIs) related to Enterobacteriaceae or Staphylococcus aureus were prospectively included in the study. The rapid ASTs were performed by incubation of positive blood cultures on MHR-SIR for 6-8 h by direct inoculation according to BSAC recommendations.

RESULTS

One hundred and sixty-seven patients with BSIs were included as MHR-guided adaptation therapy cases. Eighty percent had Enterobacteriaceae-related BSIs, of which 12 (9%) were ESBL producers and 20% were S. aureus-related BSIs. A urinary or intra-abdominal infection was observed in 44.3% and 19.8%, respectively, of Enterobacteriaceae-related infections. The most frequent sources of infections for S. aureus BSIs were cutaneous and endovascular, in 43% and 23% of cases, respectively. Forty-four percent of the patients benefited from therapeutic modification according to the results of the MHR-SIR AST. Thus, empirical antibiotic therapy was modified by using antibiotic therapy that had too wide a spectrum or was unsuitable in 26% and 18% of cases, respectively. Compared with the 24 h required for the reference method, the median length of time to provision of susceptibility test results by MHR-SIR was 7 h.

CONCLUSIONS

This study showed a significant time saving (17 h) on the appropriateness of antibiotic prescription and demonstrated a significant impact regarding the choice and reduction of the spectrum of antibiotic therapy.

Deficiency of miR-208a Exacerbates CCl4-Induced Acute Liver Injury in Mice by Activating Cell Death Pathways

Acute liver injury (ALI) is associated with multiple cellular events such as necrosis, apoptosis, oxidative stress and inflammation, which can lead to liver failure. In this study, we demonstrate a new role of microRNA (miR)‐208a in ALI. ALI was induced in wild‐type (WT) and miR‐208a knockout (KO) mice by CCl₄ administration. Increased alanine aminotransferase and decreased hepatic miR‐208a levels were found in WT mice after acute CCl₄ treatment. Histopathological evaluations revealed increased necrosis and decreased inflammation in miR‐208a KO compared with WT mice after CCl₄ treatment. CCl₄ treatment induced a higher alanine aminotransferase elevation and increased numbers of circulating extracellular vesicles (exosomes and microvesicles) in miR‐208a KO compared with WT mice. We found increased CCl₄‐induced nuclear factor kappa B activation and tumor necrosis factor‐α induction and decreased monocyte chemoattractant protein 1 levels in miR‐208a KO compared with WT mice. Terminal deoxynucleotidyl transferase–mediated deoxyuridine triphosphate nick‐end labeling assay indicated aggravated hepatic apoptosis and necrosis in CCl₄‐treated miR‐208a KO compared with WT mice. CCl₄ treatment induced a greater increase in cleaved caspase‐8, p18, and caspase‐3 in miR‐208a KO compared with WT mice. p53 is involved in various cell death pathways, including necrosis and apoptosis. Our in silico analysis revealed p53 as a predicted miR‐208a target, and we found enhanced p53 and cyclophilin D protein expressions in miR‐208a KO mice after CCl₄ treatment. Increased liver injury in miR‐208a KO mice was further associated with increased Bax (B cell lymphoma 2–associated X protein) and p21 expression. Our in vitro results indicated a role of miR‐208a in cell death. We found that CCl₄‐induced cytotoxicity was partially rescued by miR‐208a overexpression in RAW macrophages. Altogether, our results revealed a role of miR‐208a in ALI in mice and suggest a role for miR‐208a in regulating cell death.

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 &lt;1 cm²) and ejection fraction&gt; 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.

Impact of a multiplex PCR assay (FilmArray®) on the management of patients with suspected central nervous system infections

Microbiological diagnosis of central nervous system (CNS) infections is challenging due to limited access to CNS samples, overlap between meningitis and encephalitis, and the multiplicity of pathogens potentially involved. We aimed to estimate the impact of a commercial multiplex PCR assay (FilmArray® meningitis/encephalitis) on the management of patients with suspicion of meningitis or encephalitis, in terms of time to diagnosis, antimicrobial agents use, duration of hospitalization, and costs. This prospective observational study was conducted at Saint Joseph Hospital (Paris, France) from December 2016 to December 2017. All CSF samples sent to the microbiology laboratory for suspicion of meningitis and/or encephalitis, with CSF cells count > 5 cells/μL, were tested by meningitis/encephalitis multiplex PCR assay. One hundred thirty patients were included. The multiplex PCR assay was positive in 33 patients (25%). Main pathogens found were Enterovirus (n = 12), Varicella-Zoster virus (n = 7), Herpes simplex virus-2 (n = 6), and Listeria monocytogenes (n = 3) as main pathogens. The multiplex PCR assay reduced time to microbiological diagnosis by 3.3 ± 1.6 days and allowed an earlier discontinuation of empirical anti-infective drugs in 42 patients (32%) and an earlier hospital discharge in 23 patients (18%), with an estimated saving of 82 hospital days overall, and a management cost reduction of 26,242 € (201 €/patient). The systematic use of the FilmArray® meningitis/encephalitis multiplex PCR assay may allow earlier diagnosis, earlier discontinuation of empirical treatment, reduced duration of stay, and costs reduction.

Mechanical Thrombectomy for Acute Ischemic Stroke Secondary to Infective Endocarditis

Intravenous thrombolysis is contraindicated in acute ischemic stroke secondary to infective endocarditis. We report our initial experience in 6 cases of proximal vessel occlusion treated with mechanical thrombectomy, which was safe (no bleeding) and effective (significant early neurological improvement) and might be useful in this clinical setting.

Performance of rapid antimicrobial susceptibility testing by disk diffusion on MHR-SIR agar directly on urine specimens

The standard method for the diagnosis of urinary tract infections is urine culture that requires 18-48 h for the identification of the bacteria and an additional 24 h until the results of antimicrobial susceptibility testing (AST) are available. We evaluated here a rapid AST method by disc diffusion performed directly on urine samples with a delay of 8 h. A total of 245 urine samples with monobacterial Gram negative observed on microscopy were tested in parallel by two AST methods. Rapid AST method was performed directly on urine samples using Rapid Mueller-Hinton (MHR-SIR) with 8-h incubation before reading and standard method was performed as usual. We compared the categorical agreement and the correlation between the diameters obtained by standard method and by MHR-SIR directly on urine samples. Over the 5285 tested combinations, we observed 5172 (97.9%) categorical agreement, 82 (1.5%) minor errors, 17 (0.3%) major errors, and 14 (0.3%) very major errors. Our results showed an excellent categorical agreement and correlations between diameters for MHR-SIR and standard methods. MHR-SIR performed directly on urine samples with monomicrobial Enterobacteriacae can predict the result of overall AST profile in 8 h with reliable results. The main advantage of MHR-SIR is that it offers the possibility of obtaining results 40 h earlier than conventional AST. The cost is estimated for less than 6 USD for 16 antibiotics, chosen by the microbiologist.

Prospective evaluation of rapid antimicrobial susceptibility testing by disk diffusion on Mueller-Hinton rapid-SIR directly on blood cultures

BACKGROUND

With the worldwide spread of antibiotic resistance, delivering antibiotic susceptibility test (AST) results in a timely manner represents a major challenge. In cases of sepsis, rapid AST may facilitate early optimization of empiric antibiotic therapy. Disc diffusion is a well-standardized AST method, however 16 to 24 h are required to achieve an overall AST profile according to antimicrobial societies.

METHODS

In this prospective pilot study, we evaluated the performance of Mueller-Hinton-Rapid-SIR (MHR-SIR) agar after 6-8 h of incubation in comparison with standard MH agar after 16 h of incubation directly on positive blood cultures caused by Enterobacteriaceae and Staphylococcus aureus from routine clinical microbiology. A total of 133 positive blood samples including 110 Enterobacteriaceae (83%) and 23 Staphylococcus aureus (17%) were tested in parallel by two direct AST methods, each using EUCAST breakpoints. For each combination bacterium and antibiotic, we compared the categorical agreement and the correlation between the diameters obtained by MHR-SIR and by standard MH.

RESULTS

Our results showed 97.7% categorical agreement for Enterobacteriaceae, with 1.4% minor errors, 0.4% major errors and 0.5% very major errors. For S. aureus, we observed 97.8% categorical agreement, 1.9% minor errors, 0.3% major errors and no very major errors.

CONCLUSION

Our results showed excellent categorical agreement and correlations between diameters for MHR-SIR and standard MH methods. MHRSIR can predict the result of overall AST profile within 6-8 h with reliable results. AST is obtained on the same day the blood culture becomes positive, with a very moderate cost.

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.

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.].

Analysis of the THz response of a simple periodic graphite-based structure

We report the observation of the dichroism effect in simple wire grid structures made of graphite on a paper substrate, i.e. we investigate the feasibility of drawing polarizers for the THz band using conventional graphite-based lead pencils. The displacement of the maximum frequency of the selective absorption phenomenon by varying the wire pitch hints at a polarizing behavior. Measurements of the maximum and minimum of transmission efficiency, extinction ratio and degree of polarization are carried out with a transmission fiber THz-TDS setup. Experimental results show a 9 dB extinction ratio for an inexpensive (<1$) home-made component.