Platelet extracellular vesicles are superior to cardiac troponin to diagnose acute coronary syndrome with short symptom duration: LEMONADE trial

Background

Acute coronary syndrome (ACS), which comprises acute myocardial infarction (AMI) and unstable angina pectoris (UAP), is one of the main causes of mortality worldwide. Cardiac troponin is the gold standard to diagnose AMI. Troponin has two main disadvantages: it is negative in patients with UAP but positive in other diseases. During ACS, activated platelets release extracellular vesicles (EVs), which promote coagulation and associate with fibrin, and contribute to thrombus formation. We hypothesized that the concentration and composition of circulating platelet EVs (1) change in blood of patients with ACS compared to patients with other causes of chest pain, and (2) thereby allow earlier diagnosis of ACS than cardiac troponin.

Purpose

We aimed to determine the diagnostic value of circulating platelet EVs as novel early biomarkers of developing ACS.

Methods

We conducted a prospective, multicentre trial enrolling 105 patients who presented to the emergency department with suspected ACS. Blood was collected at admission to measure the concentration of EVs and cardiac troponin. Flow cytometry (Apogee A60-Micro) was used to determine plasma concentrations of platelet EVs exposing P-selectin (CD61+/CD62p+) and fibrin (CD61+/fibrin+).

Results

Plasma concentrations of platelet EVs exposing fibrin was lower in patients with ACS, compared to patients with other causes of chest pain (p=0.023) and lower in patients with an occlusive thrombus compared to non-occlusive plaque (p=0.015). Fibrin exposing-EVs were independent predictors of ACS (OR 8.2, CI 1.3–16.4) in multivariate analysis, allowing to diagnose ACS with 75% sensitivity and 72% specificity. Among patients with pain onset less than 2 hours before presentation, fibrin-exposing EVs had substantially better diagnostic performance than troponin (area under the ROC curve 0.90 vs. 0.74, respectively). Regarding other causes of chest pain, fibrin-exposing EVs were the lowest in patients with ACS, higher in patients with other cardiological causes of chest pain, and the highest in patients with non-cardiological causes of chest pain (p=0.036).

Conclusions

Circulating fibrin-exposing EVs are early biomarkers of developing ACS, superior to cardiac troponin in patients with pain onset less than 2 hours before presentation. Incorporation of EV measurements into the ACS diagnostic algorithm might revolutionise thrombotic risk stratification in the emergency setting.

Funding Acknowledgement

Type of funding sources: Public grant(s) – National budget only. Main funding source(s): Specialised Research Fellowship, “Club 30” of the Polish Society of Cardiology

Safety and effectiveness of very high-power short duration ablation in patients with atrial fibrillation: early results

Background

Pulmonary vein isolation (PVI) is at the forefront of treatment methods of rhythm control in patients with atrial fibrillation (AF) (1). The novel contact-force sensing catheter, QDot MicroTM (Biosense Webster) was designed to improve effectiveness of AF ablation and allow better time management due to shorter procedure time. It is a very high power-short duration (vHP-SD) catheter optimized for high density mapping and temperature control, which enables the application of high energy (up to 90W, 4s) (2).

Purpose

The aim of the study was to compare the QDot MicroTM catheter with the ThermoCool SmarttouchTM SF catheter with regard to the effectiveness and safety of PVI ablation.

Methods

It is a single center, cross-sectional, observational study enrolling 101 consecutive patients suffering from symptomatic paroxysmal or persistent AF, referred for first catheter ablation between 16 December 2019 and 03 December 2021. In 47 procedures (mean age 54 years; 70% male; 77% paroxysmal) the QDot Micro catheter was used (vHP-SD group; Qmode+ 90W, 4s), whereas the remaining 54 patients (mean age 57 years; 70% male; 67% paroxysmal) were treated with the ThermoCool SmarttouchTM SF catheter (control group, Ablation Index guided ablation). The primary endpoint was freedom from AF at 3-months after ablation. The secondary endpoints included the amount of opioids administered as well as the incidence of early-onset treatment-emergent adverse events (TEAEs).

Results

AF recurrence was documented in 14.9% patients in vHP-SD group and in 31.5% patients in control group (p=0.06). The mean dose of remifentanil was reported to be lower during Qmode+ catheter-based PVI (0.50 (0.40–0.60) vs. 0.70 (0.55–0.90) mg; p<0.001). There was no statistically significant difference in TEAEs between both groups (6.3 vs. 0%; p=0.10). One severe adverse event (cerebral vascular incident 2 days after PVI – due to thrombus in the left ventricle) was observed in vHP-SD group.

Conclusions

This study suggests that the vHP-SD ablation is safe and enables sedative-analgesic medications demand reduction during procedure. vHP-SD mode may enhance the success rate of catheter-based PVI, however further research is needed to provide additional evidence of its superiority.

Funding Acknowledgement

Type of funding sources: None.

Leukocyte extracellular vesicles as the first biomarkers to predict outcomes in patients undergoing percutaneous aortic valve replacement

Background

Transcatheter aortic valve implantation (TAVI) is a novel treatment for aortic stenosis (AS), associated with better outcomes than surgical aortic valve replacement in high-risk patients. However, up to 29% of patients annually experience major adverse cardiac and cerebrovascular events (MACCE) after TAVI. MACCE are mostly caused by atherothrombosis, i.e. formation of platelet aggregates (thrombi) on ruptured atherosclerotic plaques. Because platelets release extracellular vesicles (EVs) during thrombus formation, we hypothesized that EVs are a biomarker to predict MACCE after TAVI.

Methods

This was a multicentre, prospective clinical study. Venous blood was collected 1 day before TAVI and at hospital discharge (n=57, mean age 79.9+6.4 years, 49% male). Flow cytometry (Apogee A60-Micro) was used to determine concentrations of plasma EVs labelled with markers for endothelial cells (CD146), leukocytes (CD45), platelets and megakaryocytes (CD61) and activated platelets (CD62p). Analysis of flow cytometry data files was fully automated. Rosetta Calibration (Exometry) and Flow-SR were used for diameter and refractive index determination. Wilcoxon signed rank test was used to compare EV concentrations before and after TAVI. The predictive value of EVs for MACCE and the cut-offs were calculated using a receiver operating characteristic curve. Logistic regression model incorporating EV concentrations and clinical characteristics was used to determine the best model for MACCE prediction.

Results

Concentrations of EVs from activated platelets increased, whereas from leukocytes decreased after TAVI, compared to the measurement before (p=0.06, p=0.04, respectively). Among 55 patients discharged from the hospital, 14 patients experienced MACCE (25%) during the median 15 months of observation. Increased baseline concentration of leukocyte EVs and male gender were the only independent predictors of MACCE in multivariable analysis (OR 4.01, 95% CI 0.77–23.77, p=0.04 for leukocyte EVs; OR 6.84, 95% CI 1.41–33.17, p=0.03 for male gender).

Conclusions

We identified increased concentrations of leukocyte EVs as new candidate biomarkers to predict MACCE after TAVI. Leukocyte EVs could be used to augment risk stratification in this patient cohort. The next step is to validate the clinical applicability of EVs to predict post-TAVI MACCE in a large-scale clinical trial.

Funding Acknowledgement

Type of funding sources: Public grant(s) – National budget only. Main funding source(s): Young Investigator Grant of the Polish Society of Cardiology

Left atrial thrombus in atrial fibrillation/flutter patients in relation to anticoagulation strategy: LATTEE registry

Funding Acknowledgements

Type of funding sources: None.

Background

Atrial fibrillation (AF) and flutter (AFl) increase the risk of thromboembolism by promoting clot formation in the left atrium. Current guidelines recommend initiation of oral anticoagulation (OAC) with vitamin K antagonists (VKAs) or, preferably, non-VKA-OACs (NOACs) in men and women with a CHA2DS2VASc score of ≥2 and ≥3, respectively. Effective OAC is also recommended 3 weeks before elective AF cardioversion or catheter ablation with pre-procedural ttransesophageal echocardiography (TEE) as an alternative. However, TEE before AF/AFl cardioversion or ablation is often performed even in anticoagulated patients, given that, in clinical practice, "effective" OAC may be difficult to achieve and/or verify.

Purpose

The aim of the study was to assess the prevalence of left atrial thrombus (LAT) in AF/AFl in relation to OAC strategy.

Methods

The Left Atrial Thrombus on Transesophageal Echocardiography (LATTEE) registry was a prospective, observational study enrolling consecutive patients with AF or AFl in whom TEE was performed before direct current cardioversion or catheter ablation, hospitalized in 13 cardiology departments in Poland. Patients’ recruitment process started from November 2018 in the coordinating centre and lasted 12 months since the beginning of the study in each participating centre or longer, i.e., until the inclusion of at least 200 patients at each participating centre (with the last patient enrolled in May 2020).

Results

Of 3109 patients enrolled, 88% were on chronic, 1.5% on transient OAC and 10% without OAC. Of patients on chronic OAC, 39% received rivaroxaban, 30% dabigatran, 14% apixaban and 18% vitamin K antagonists (VKA). Patients on apixaban were oldest, had worst renal function and highest both bleeding and thromboembolic risk, and more often received reduced doses. Overall, prevalence of LAT was 8.0% (7.3% on chronic OAC vs. 15% without OAC; p<0.01). In patients on VKA, prevalence of LAT was doubled compared to patients on non-VKA-OACs (NOACs) (13% vs. 6.0%; p<0.01), even after propensity score matching (13% vs. 7.5%; p<0.01) and in multivariable logistic regression (OR 1.9, 95% confidence interval 1.4-2.8). Prevalence of LAT in patients on apixaban was higher (9.8%) than in those on rivaroxaban (5.7%) and dabigatran (4.7%; p<0.01 for both comparisons). However, in propensity score matching and multivariable logistic regression, there was no difference in the risk of LAT between apixaban and other NOACs.

Conclusions

Prevalence of LAT in AF is non-negligible even on chronic OAC. In the real-world AF/AFl population, the risk of LAT seems higher on VKA compared to NOAC, and similar between different NOACs.

Stress echocardiography in patients with ischemic mitral regurgitation and left ventricular dysfunction qualified to cardiosurgery treatment

Funding Acknowledgements

Type of funding sources: None.

Introduction

Ischemic mitral regurgitation (IMR) is predominantly related to left ventricle (LV) remodeling and mitral valve deformation. Although coronary artery bypass grafting alone (CABGa) or with mitral annuloplasty (CABGmp) is considered the best therapeutic strategies for patients with IMR, some recurrences are still reported.

Purpose

The aim of this study was to evaluate use of the mitral deformation indices (MDI) as a predictor of recurrence of IMR in 1-year follow-up after surgery.

Methods

A total of 145 patients after myocardial infarction with significant IMR, eligible for CABG, were prospectively enrolled in the study. Patients were referred for CABGa (gr.1; n = 90) or CABGmp (gr.2; n = 55), based on clinical assessment and the results of rest and stress echocardiography. One year after surgery each patient underwent the evaluation of cardiovascular events. Univariable logistic regression analysis was used to identify factors of recurrence of IMR in 1 year follow-up.

Results

Logistic regression analysis revealed that in CABGa group preoperative changes of TA and CH during DBX remained the predictors of the recurrence of IMR in 12 months follow-up. TAdbx > 1 cm2 provided sensitivity of 90% and specificity of 29%, (AUC 0.6436); The best cut-off value for CHdbx was 0.4 cm (sensitivity 90%, specificity 34%; AUC 0.6432). In both groups no significant differences were observed in 12-month mortality (1.2% vs 0%; p = 1.0), hospitalizations due to the heart failure (HF) exacerbation (5.9% vs 8.5%; p = 0.72) and in the incidence of the composite endpoint (deaths/CV hosp/stroke) (7% vs 8.5%; p = 0.742).

Conclusion

Preoperative assessment of MDI changes during dbx can be used to identify patients with IMR at increased risk of recurrence of significant IMR in 1 year follow-up. Abstract Figure 1  Abstract Figure 2

Right ventricular dysfunction in patients with non-severe ischemic mitral regurgitation qualified to cardiosurgery treatment

Funding Acknowledgements

Type of funding sources: None.

Introduction

Right ventricular (RV) dysfunction worsens prognosis in patients (pts) after myocardial infarction (MI).

Purpose

The purpose of this study was to assess RV function as a predictor of mortality and hospitalizations due to exacerbation of HF in pts with ischemic mitral regurgitation (IMR) qualified for cardiosurgical treatment - coronary artery by-pass grafting alone (CABGa) or CABG with mitral reconstruction (CABGmr).

Methods

We prospectively analyzed 104 pts (M 57, 64 ± 7 years) with non-severe IMR, 3-24 weeks after MI. Effective regurgitation orifice (ERO) was used for quantitative IMR assessment (non-severe ≥10-20 mm²). All the pts were qualified for CABG (multiple vessel coronary disease, ejection fraction (EF)-44 ± 8%). The patients were referred for CABGa (gr.1; n = 77) or CABGmr (gr.2; n = 27) based on clinical assessment, 2D and 3D echo at rest and exercise. Tricuspid annular plane systolic excursion (TAPSE) was acquired to evaluate RV function (measured with M-mode imaging in the 4-chamber view). RV function was related to clinical outcome (median follow-up: 12 months).

Results

During the follow-up period of 12 months, 5 deaths (5 %) and 8 hospitalizations (8%) due to exacerbation of HF occurred. With use of the following cut-off points of TAPSE ≤ 12 mm (group I), and TAPSE >12 mm (group 2)—an association was found between the lower TAPSE and increased mortality. In group 1 (n =54 pts), 5 pts (9.2%) died and 6 pts was hospitalized due to HF (11.1%); in group 2 (n =50), no patient died, and 2 pts was hospitalized (4%). There was a significant difference (p = 0.02) in clinical outcomes between group I and II. ROC analysis identified TAPSE ≤12 mm as predictive cut-off for prediction adverse clinical outcome in all study group: (death: sensitivity 80%, specificity 76%, area under curve [AUC] = 0.807 (Fig.1); death and HF hospitalizations: sensitivity 69%, specificity 79%; AUC =0.767).

Conclusion

TAPSE is simple and useful quantitative measurement of RV function and have a predictive value in pts with non-severe IMR referred for cardiosurgery treatment. Abstract Figure 1

Right ventricle dysfunction in patients with takotsubo syndrome

Funding Acknowledgements

Type of funding sources: None.

OnBehalf

Pol-tako

Background 

Takotsubo syndrome  (TTS) is a clinical condition that mimics acute myocardial infarction and is characterised by acute left ventricle dysfunction. However, right ventricle (RV) involvement can also occur. 

Purpose  

The aim of our study was to compare clinical characteristic, in-hospital complications and in-hospital mortality in patients with TTS with and without RV dysfunction. 

Methods  

209 consecutive patients with TTS were included in the study. Among them, 13,9% (29 patients) had RV dysfunction according to echocardiography evaluation. Clinical symptoms at admission to hospital was similar in both groups. There weren’t differences in time from onset of symptoms to the hospital admission in both groups. 

Results  

Patients with RV dysfunction was older (75,6 vs 69.4y). Left ventricle ejection fraction (LVEF) at 1st and 3rd day of hospitalisation was lower in patients with TTS with RV involvement in comparison to patients without RV dysfunction (37.9 vs 41.9%, 42,1 vs 47.3% and 46.1 vs 50.9%, respectively). However, at 5th day EF LV was similar in both groups. Tricuspid annular plane systolic excursion (TAPSE) was lower in patients with RV dysfunction at 1st and 3rd day (17 vs 21mm and 19 vs 21.6 mm, respectively). Pulmonary oedema and cardiogenic shock occurred less often in patients with RV involvement (6.9 vs 17.7% and 0 vs 4.4%). In hospital mortality was similar in both groups (3.4 and 2.2%).  Moreover, there was not difference in the length of hospitalisation (11.9 vs 10.1 days). 

Conclusions 

Right ventricle in patients with TTS can occur in about 14% patients. In addition to impaired RV function also LVEF is more depressed in the first days. However, in hospital mortality is similar.

Sex differences in patients with takotsubo syndrome

Funding Acknowledgements

Type of funding sources: None.

OnBehalf

Pol-tako

Introduction 

Takotsubo syndrome (TTS) is an acute revesible left ventricular dysfunction which occurs mainly in postmenopausal women. Despite the fact that the most patients with TTS are postmenopausal women and the possible patomechanism is related to female hormones, including estrogens, men also suffer from TTS. 

Objectives 

The goal of this study was to compare course of disease and prognoses in male and female patients with TTS. 

Patients and Methods 

The analysis included 210 patients (192 women and 18 men) hospitalized at the academic hospital from the year 2006 to 2020. 

Results 

Physical stress was trigger of TTS more often in men than women (50 vs. 38%). There were no differences in the frequency of risk factors and comorbidities, with the exception of higher prevalence of smoking in men. Markers of cardiac necrosis were similar in both groups.  At admission and peak NTproBNP levels were significantly more elevated in women (1527 vs. 3152 and 3752 vs. 5079pg/ml, respectively).  ST depression was found more frequently in men than in women (22 vs. 5%). Ejection fraction was lower among male patients at discharge (50 vs. 60%), despite the same length of hospitalization. Beta-adrenolytics and statins were more frequently prescribed for women than for men (90 vs 78% and 68 vs. 31%) whereas ACEI was prescribed in 96% men and 79% women. Moreover, there was P2Y12 inhibitors were more often used in men (33 vs 10.4%). In-hospital complications (arrhytmias, mechanical complications, cardiogenic shock) were similar in both groups. However, mortality rate was higher in women (3 vs. 0%).  

Conclusions 

Clinical course in patients with TTS is similar in women and men. However, in-hospital mortality was higher in women.

Double superior vena cava and left brachiocephalic vein agenesis: a rare systemic vein anomaly and potential source of cardiac implantable electronic device and central venous catheter placement complications

Abnormal systemic vein development produces anomalous veins, which - in the case of persistent left superior vena cava and/or left brachiocephalic vein - exhibit considerable topographic and morphometric differences in comparison with their usual anatomy. The nature and extent of those developmental anomalies - detected during intravenous procedures, such as cardiac implantable electronic device (CIED) lead insertion or central venous catheter placement - may hinder the procedure itself and/or adversely affect its outcome, both at the stage of cardiac lead advancement through an abnormally shaped vessel and lead positioning within the heart. This may lead to problems in achieving optimal sensing and pacing parameters and in ensuring that the patient cannot feel the pacing impulses. These events accompanied a de novo CIED implantation procedure in the patient with a double superior vena cava and left brachiocephalic vein agenesis, who ultimately required reoperation.

Clinical characteristics and risk profile of patients with atrial fibrillation with mid-range ejection fraction, insights from the Polish part of EORP-AF Long-Term General Registry

Background

Atrial fibrillation (AF) comprises a wide range of patients (pts), from those with preserved to those with reduced left ventricular ejection fraction (LVEF). According to 2016 ESC guidelines, pts with LVEF in the range of 40–49% represent a “grey area”, which is defined as heart failure with mid-range ejection fraction (HFmrEF). Not much is known about the clinical characteristics of AF pts with mid-range ejection fraction.

Purpose

To determine the potential differences in the clinical characteristics, risk profile, and the outcomes of AF with moderate systolic dysfunction, measured by LVEF.

Methods

The EURObservational Research Programme on AF (EORP-AF) Long-Term General Registry analyzed consecutive AF patients who have presented to cardiologists in 250 centers from 27 European countries, including 25 centers from Poland. We analyzed data collected at baseline and at a 1-year follow-up visit from 568 Polish patients included in 25 Polish centers in the years 2013–2016. Pts were divided into three groups based on LVEF: the preserved LVEF (pEF) group (LVEF ≥50%), the mid-range LVEF (mrEF) group (40–49%), and the reduced LVEF (rEF) group (<40%).

Results

117/568 pts with rEF represented 20,6%, 105/568 mrEF 18,5% and 346/568 pEF 60,9% of the whole analyzed group. With regard to the most typical risk factors, the mrEF population appeared between rEF and pEF, presenting a moderate risk profile with the exception of hypertension, which was the most common in the mrEF group. While permanent AF was the most common in the rEF group and paroxysmal in the pEF pts, pts with mrEF had a higher rate of long-lasting persistent AF. Taking into account the risk factors profile, surprisingly, pts with AF and mrEF more often presented with dyspnea/shortnes of breath (mrEF 38,1% vs. rEF 18,8% vs. pEF 22,5%; p=0,001) and fatigue (mrEF 38,1% vs. rEF 23,9% vs. pEF 25,4%; p=0,025). AF pts with mrEF also had the highest thrombo-embolic risk estimated with the CHA2DS2-VASc score (mrEF 4 [2–5], n=105; rEF 3 [2–5], n=117, pEF 3 [2–4], n=346, p=0.005). However, this did not translate into the highest number of thromboembolic events after one year which did not significantly differ (mrEF 10.5%, rEF 15.4%, pEF 11.3%, p=0.30) between the three groups.

Conclusions

The risk factor profile of AF pts with mrEF was milder than for those with rEF and more severe than for pEF pts. AF pts with mrEF more often presented HF symptoms. Their estimated thrombo-embolic risk was higher but the number of events in the one year follow-up did not significantly differ between groups.

Funding Acknowledgement

Type of funding source: None

P1384Radiation safety and electrophysiologists: radiation protection status

INTRODUCTION

 Ionizing radiation is typically used during variety electrophysiological (EP) procedures, although it may contribute to deterministic effects especially for staff. 

PURPOSE

 The purpose of this study was to perform an analysis of EP operators’ radiation protective devices for occupational exposure. 

METHODS

 Data reported herein were gathered from international, multi-site, prospective, Go 4 Zero Fluoroscopy registry. The registry encompassed 25 European EP centers, and up to 5 operators from each center. The presence of operators’ X-ray protection tools was examined to determine the level of operators’ protection. Additionally, the tests included availability of measures to decrease radiation output and exposure control measures. Finally, the analysis of correlation between the X-ray protection and degree of operators’ experience (<5, 5-15,>15 years) as well as number of procedures performed per month (1-9, 10-19, 20-39, >40 procedures/month) was performed. 

RESULTS

 Our analysis included 95 operators (median age: 39 years, 85% of male, median training time: 5 years). The whole study group performed annually medical examinations due to radiation exposure and 56% of them received dosimetry reports once a month, 5% - once every 3 months, and 39% - once a year. Irrespectively of experience or number of performed procedures the most frequently used X-ray protection tools (used by >80% of group) were lead apron, thyroid shields, screen below the table, glass in the lab, and least often (used by < 6% of group) – protective gloves and cabin. The most often exposure control measures used were chest (95%) followed by collar (31%), ring (24%) and eye (7%) dosimeters. The inverse correlation between level of experience and measures to decrease radiation output was observed (collimation: 84%, 80% and 78%; minimizing the tube-to intensifier distance: 100%, 93% and 91% of operators with <5, 5-15 and >15 years of experience, respectively). There were not observed differences between type of radiation protection equipment and operators’ level of experience or number of procedures. Additionally, there were no differences between male and female operators regarding protective equipment, expect eyeglasses or cabin that were more often used by men. Operators who were protected by >4 X-ray protection tools were exposed for higher radiation levels as compared to those protected by <4 X-ray protection tools (median [IQR] radiation exposure: 0.6 [0.2-1.1] vs 0.2 [0.1-0.2] mSv per month, p < 0.0001; 1.1 [0.1-12.0] vs 0.5 [0.1-1.1] mSv per year, p < 0.0001). There were no differences between the type of (universitary vs non-universitary) or institution’s localization (Eastern vs Central vs Western Europe) and used protective equipment.  

CONCLUSIONS

 Both proper radiation protective equipment, and regular medical examination due to professional exposure are mandatory to reduce radiation exposure in practice.

P1573 Late recovery of left ventricular function in patients with non-severe ischemic mitral regurgitation and multivessel disease qualified to cardiosurgery treatment

Purpose

In patients (pts) after myocardial infarction (MI) with chronic left ventricle (LV) dysfunction, the presence and degree of ischemic mitral regurgitation (IMR) are predominantly related to LV remodelling and mitral valvular deformation. The aim of this study was to compare functional recovery (LVFR) as well as reverse remodelling of the left ventricle (LVRR) in pts with non-severe IMR qualified for cardiosurgical treatment - coronary artery bypass grafting alone (CABGa) or CABG with mitral repair (CABGmr in the 12-month follow-up.

Materials and methods

A total of 100 pts (mean age 64,4 ± 7,9 years) after MI, eligible for CABG, were included in a prospective study. Echo and clinical assessment were performed before and 12-months after surgery. Pts were referred for CABG a(gr.1; n = 74) or CABGmr (gr.2; n = 26) based on clinical assessment, 2D echo at rest and exercise and myocardial viability assessment (low dose dobutamine - dbx). Effective regurgitation orifice area (EROA) was used for quantitative IMR assessment. An increase in EF≥ 5% (ΔEF) from baseline value was considered as LVFR. A decrease in LV end-systolic volume > 15% from baseline value was considered as LVRR. Multivariable logistic regression analysis was used to identify the strongest factors of lack of LVFR and LVRR.

Results

An LVFR was observed, at late control, in 35 (49%) of pts in the CABGa group and in 11 (48%) of pts in CABGmr group (p = 0,948). LVRR was observed in 41 (56%) of pts in the CABGa group and in 16 (70%) of pts in CABGmr group 12 months follow-up (p = 0,5). In pts with LVFR, there was a lower incidence of at least moderate IMR at follow-up (ΔEF dbx≥5% vs ΔEFdbx < 5%:11% vs 30% pts; p = 0,05). Multivariable logistic regression analysis revealed that in both CABGa and CABGmr group only preoperative age and EF changes during stress echo remained the independent predictors of the lack of LVFR in 12 months follow-up (table 1).

Conclusions

1. LVFR and LVRR were reported in most of the pts in both analyzed groups.

2. Preoperative assessment of changes EF during dbx (ΔEFdbx)can be used to identify pts with IMR at increased risk of lack of improvement in LV function and risk of residual IMRin 12-month f-up after surgery.

Parameters Odds ratio (OR) Odds ratio (OR) p CABGa vs CABGmr 0,644 0,215 - 1,927 0,432 Age (increase by every 5 years) 1,11 1,039 - 1,879 0,003 ΔEF dbx (increase by every 5%) 0,21 0,096 - 0,46 <0,001 Table 1. Prognostic factors lack improvement in left ventricle function.

Persistence of phylogeographic footprints helps to understand cryptic diversity detected in two marine amphipods widespread in the Mediterranean basin

Amphipods of the genus Gammarus are a vital component of macrozoobenthic communities in European inland and coastal, marine and brackish waters of the Mediterranean and the Black Sea. Exceptional levels of cryptic diversity have been revealed for several widespread freshwater Gammarus species in Europe. No comprehensive assessment has yet been made for brackishwater counterparts, such as Gammarus aequicauda and G. insensibilis, which are among the most widely dispersed members of the so-called "G. locusta group" in the Mediterranean and in the Black Sea. Here we probe the diversity of these morphospecies examining the partitioning of mtDNA and nDNA across multiple populations along their distribution range and discuss it within the regional paleogeographic framework. We gathered molecular data from a collection of 166 individuals of G. aequicauda and G. insensibilis from 47 locations along their distribution range in the Mediterranean including the Black Sea. They were amplified for both mitochondrial COI and 16S rRNA as well as the nuclear 28S rRNA. All five MOTU delimitation methods (ABGD, BIN, bPTP, GMYC single and multiple threshold models) applied revealed deep divergence between Black Sea and Mediterranean populations in both G. aequicauda and G. insensibilis. There were eight distinct MOTUs delimited for G. aequicauda (6-18% K2P) and 4 MOTUs for G. insensibilis (4-14% K2P). No sympatric MOTUs were detected throughout their distribution range. Multimarker time-calibrated phylogeny indicated that divergence of both G. aequicauda and G. insensibilis species complexes started already in the late Oligocene/early Miocene with the split between clades inhabiting eastern and western part of the Mediterranean occurring in both species at the similar time. Our results indicate a high cryptic diversity within Mediterranean brackishwater Gammarus, similar to that observed for freshwater counterparts. Moreover, the phylogenetic history combined with the current geographic distribution indicate that the evolution of both studied Gammarus morphogroups has been strongly connected with the geological events in the Mediterranean Basin and it reflect the turbulent history of the area.

Characterizations of handwashing sink activities in a single hospital medical intensive care unit

BACKGROUND

Handwashing sink drains are increasingly implicated as a potential reservoir of antibiotic-resistant bacteria in hospital outbreaks; however, usage patterns that may promote this source remain unknown.

AIM

To understand behaviours in the intensive care unit (ICU) that may facilitate establishment and nosocomial transmission of multidrug-resistant Gram negatives from a sink-trap reservoir to a patient.

METHODS

Motion-sensitive cameras captured anonymized activity paired with periodic in-person observations during a quality investigation from four ICU sinks (two patient rooms and two patient bathrooms) in a university hospital.

FINDINGS

We analysed 4810 sink videos from 60 days in patient rooms (3625) and adjoining bathrooms (1185). There was a false-positive rate of 38% (1837 out of 4810) in which the camera triggered but no sink interaction occurred. Of the 2973 videos with analysed behaviours there were 5614 observed behaviours which were assessed as: 37.4% medical care, 29.2% additional behaviours, 17.0% hand hygiene, 7.2% patient nutrition, 5.0% environmental care, 4.2% non-medical care. Handwashing was only 4% (224 out of 5614) of total behaviours. Sub-analysis of 2748 of the later videos further categorized 56 activities where a variety of nutrients, which could promote microbial growth, were disposed of in the sink.

CONCLUSION

Several non-hand hygiene activities took place regularly in ICU handwashing sinks; these may provide a mechanism for nosocomial transmission and promotion of bacterial growth in the drain. Redesigning hospital workflow and sink usage may be necessary as it becomes apparent that sink drains may be a reservoir for transmission of multidrug-resistant bacteria.

Structure of isochorismate synthase DhbC from Bacillus anthracis

The isochorismate synthase DhbC from Bacillus anthracis is essential for the biosynthesis of the siderophore bacillibactin by this pathogenic bacterium. The structure of the selenomethionine-substituted protein was determined to 2.4 Å resolution using single-wavelength anomalous diffraction. B. anthracis DhbC bears the strongest resemblance to the Escherichia coli isochorismate synthase EntC, which is involved in the biosynthesis of another siderophore, namely enterobactin. Both proteins adopt the characteristic fold of other chorismate-utilizing enzymes, which are involved in the biosynthesis of various products, including siderophores, menaquinone and tryptophan. The conservation of the active-site residues, as well as their spatial arrangement, suggests that these enzymes share a common Mg(2+)-dependent catalytic mechanism.

Structure of anabolic ornithine carbamoyltransferase from Campylobacter jejuni at 2.7 Å resolution

Anabolic ornithine transcarbamoylase (aOTC) catalyzes the reaction between carbamoyl phosphate (CP) and L-ornithine (ORN) to form L-citrulline and phosphate in the urea cycle and L-arginine biosynthesis. The crystal structure of unliganded aOTC from Campylobacter jejuni (Cje aOTC) was determined at 2.7 Å resolution and refined to an R(work) of 20.3% and an R(free) of 24.0%. Cje aOTC is a trimer that forms a head-to-head pseudohexamer in the asymmetric unit. Each monomer is composed of an N-terminal CP-binding domain and a C-terminal ORN-binding domain joined by two interdomain helices. The Cje aOTC structure presents an open conformation of the enzyme with a relatively flexible orientation of the ORN-binding domain respective to the CP-binding domain. The conformation of the B2-H3 loop (residues 68-78), which is involved in binding CP in an adjacent subunit of the trimer, differs from that seen in homologous proteins with CP bound. The loop containing the ORN-binding motif (DxxxSMG, residues 223-230) has a conformation that is different from those observed in unliganded OTC structures from other species, but is similar to those in structures with bound ORN analogs. The major differences in tertiary structure between Cje aOTC and human aOTC are described.

Hereditary non-polyposis colorectal cancer: clinical and molecular evidence for a new entity of hereditary colorectal cancer

BACKGROUND

Hereditary non-polyposis colorectal cancer (HNPCC) is clinically defined by familial clustering of colorectal cancer and other associated tumours.

METHODS

By thorough molecular and clinical evaluation of 41 families, two different groups were characterised: group 1, 25 families with truncating mutations in MLH1 or MSH2 (12 novel mutations); and group 2, 16 Amsterdam positive families without mutations in these genes and without microsatellite instability in their corresponding tumours.

RESULTS

Significant clinical differences between these two groups were found. Firstly, earlier age of onset for all colorectal cancers (median 41 v 55 years; p < 0.001) and all tumours (median 43 v 56 years; p = 0.022) was observed, comparing groups 1 and 2. Secondly, 68% of the index colorectal cancers were localised proximally of the splenic flexure in group 1 compared with 14% in group 2 (p < 0.010). Thirdly, more synchronous and metachronous colorectal (p = 0.017) and extracolorectal tumours (p < 0.001) were found in group 1. Fourthly, a higher colorectal adenoma/carcinoma ratio (p = 0.030) and a tendency towards more synchronous or metachronous adenomas in group 2 (p = 0.084) was observed, indicating a slower progression of adenomas to carcinomas. As three mutation negative tumours revealed chromosomal instability after comparative genomic hybridisation, these tumours may be caused by one or more highly penetrant disease alleles from the chromosomal instability pathway.

CONCLUSION

These data show that HNPCC includes at least two entities with clinical and molecular differences. This will have implications for surveillance programmes and for cancer research.

Use and interpretation of on/off diaries in Parkinson's disease

OBJECTIVE

To explore the use and interpretation of self reported on/off diary data for assessment of daily motor fluctuations in Parkinson's disease.

METHODS

26 consecutive non-demented patients with fluctuating Parkinson's disease received standardised training on how to fill out the four category CAPSIT-PD on/off diary, followed by four hours of clinical observation and four weeks of daytime on/off diaries every 30 minutes at home.

RESULTS

Overall patient-clinician agreement in diary entries was good (kappa = 0.62; weighted kappa = 0.84). Agreement for individual diary categories was good for "off" and "on with dyskinesias" (kappa = > or =0.72), but moderate for "partial off" and "on" (kappa = 0.49). The overall validity of patient kept diaries was supported by expected symptom severity variability across diary categories, as assessed in the clinic. One day's home diary data failed to predict outcomes from the full four weeks for all diary categories, and data from three days failed to yield good prediction (predefined as R(2) = > or =approximately 0.7) for the time spent in "off" and "partial off". Data from one week yielded good prediction (R(2) = > or =0.74) in all instances except "partial off", which could not be well predicted even when two weeks' home diary data were considered (R(2) = 0.52).

CONCLUSIONS

The data provide support for the overall accuracy and validity of the four category CAPSIT-PD on/off diary, but suggest that a three category diary format may improve accuracy and validity. Interpretation of diary data beyond the assessed time frame should be made with caution unless diaries have been kept for sufficiently long periods.