AHEPA University Hospital Research Articles

Neurosurgical Patient's Quality of Life: A Questionnaire-Based Study.

The burden of disease, as well as social and epidemiological factors, have a clear impact on a patient's quality of life. Especially in neurosurgery, patients commonly experience a decline in their quality of life. This study aims to assess the quality of life of neurosurgical patients and evaluate the impact of epidemiologic and disease-related factors. Adult, non-trauma neurosurgical patients were included in the study, which took place in the Neurosurgical Departmentat AHEPA University Hospital. Self-administered questionnaires including the 36-Item Short Form Survey Instrument (SF-36) and the EQ-5D-5L were usedto assess the overall patient's quality of life. Additionally, all patients were asked to provide data on the perceived severity of the disease and the extent of information regarding their health condition. Epidemiologic factors including gender, age, education level, and rural or urban living environment were also taken into account. Statistical analysis was performed to assess the impact of the aforementioned parameters on the patient's quality of life. In total, 74 patients were included in the study (56.9% male, mean age: 51 years). In general, better mean scores were observed in general health perception, vitality, social role functioning, and mental health, whereas the lowest values were detected in the reported physical and emotional role functioning. No statistically significant differences were observed among genders. Age was found to impact the general health perception and EQ-VAS (visual analog scale) score, while physical functioning presented significant differences depending on the patient's living environment and education level, with better scores for rural residents and secondary education graduates. The perceived severity of the health condition presented a significant negative effect on the EQ-VAS score, while it affected significantly physical functioning, with better outcomes reported by patients dealing with more serious diseases.Finally, in most of the evaluated categories, the level of information seemed to increase the reported quality of life, even though statistical significance was not confirmed. Quality of life should be taken into account when treating neurosurgical patients, and utilizing measuring tools assists in objectively evaluating their well-being. Most parameters that influence the patient's quality of life are fixed. Therefore, based on our study results, healthcare professionals should prioritize providing comprehensive information regarding the patient's disease and treatment, as the level of information seems to improve the overall patient's quality of life.

Angiopoietins as Predictor Indexes in COVID-19 Patients in Delta and Omicron Waves.

This study aimed to explore the correlation between Angiopoietin-1 (Ang-1) and Angiopoietin-2 (Ang-2) concentrations and the Angiopoietin-2/Angiopoietin-1 ratio (Ang-2/Ang-1) with clinical outcomes, potentially serving as disease severity and survival biomarkers. A study at AHEPA University Hospital involved 90 Coronavirus Disease 2019 (COVID-19) adult patients, 30 hospitalized intensive care units (ICU), 30 inward units (non-ICU), and 30 asymptomatic non-hospitalized individuals as controls. Estimated endothelial dysfunction markers related to angiogenesis were measured. There was a statistically significant difference only between outpatient and hospitalized patients (non-ICU-ICU groups) for the Ang-1 and Ang-2 indices. The Ang-2/Ang-1 ratio has differed significantly among the individual patient groups. An ROC analysis was conducted to find an optimal threshold for distinguishing between (outpatients-non-ICU) and (non-ICU-ICU) groups. It was based on Youden's index of 0.1122 and 0.3825, respectively. The Ang-1, Ang-2 levels, and Ang-2/Ang-1 ratio were analyzed as severity indicators in COVID-19 patients. The Ang-2/Ang-1 ratio demonstrated better prognostic and diagnostic utility than individual biomarker levels. Monitoring the Ang-2/Ang-1 ratio can identify COVID-19 patients at risk and assist clinicians in tailoring treatment strategies to improve outcomes.

Significant contribution of chronotype to emotional well-being in chronic psychiatric outpatients in Greece

Circadian rhythms are pivotal for human functioning, and their disruption holds significant implications for well-being. One common source for circadian disruptions is circadian misalignment that can be related to chronotypes. Chronotypes refer to an individual's preferred timing for sleep and wakefulness. Individuals with late chronotypes are at a disadvantage in the morning-oriented modern world and are demonstrated to have negative consequences in many aspects of life. In the context of psychiatric disorders, chronotypes are related to prevalence of disorders and to treatment effects but less attention is given to the relationship between chronotype and well-being in chronic psychiatric patients. The current study aims to elucidate the extent to which individual chronotypes contribute to emotional well-being within a cohort of individuals with chronic psychiatric disorder in outpatient clinic.Participants (n = 100) were recruited from the outpatient clinic of the 3rd Department of Psychiatry, AHEPA University Hospital, Thessaloniki, Greece, and the AX Mental Health Outpatient Clinic in Heraklion, Crete, Greece. Most participants were diagnosed within the F2 cluster, Psychotic disorders (n = 38), or F3 cluster, Mood (affective) disorders (n = 48). The Morningness-Eveningness Questionnaire (MEQ) was employed to assess chronotype. The STAI-Y1, CES-D, QoL Uniscale and RASS Questionnaires were used to assess aspects of emotional well-being. A single measure of emotional well-being was generated using Z-score transformation. Student's t-test, ANOVAs and Pearson's correlations were used to identify parameters contributing to emotional well-being, followed by a comprehensive regression model.Results show a significant contribution to emotional well-being by “psychiatric diagnosis” with schizophrenia/schizoaffective patients showing better emotional well-being compared with the “other” group, “receiving treatment” with patients receiving treatment showing higher score than ones who do not receive treatment, and “morningness/eveningness preference” where morningness was associated with higher score of emotional well-being. No other demographic or health-related parameters were significantly associated with emotional well-being score.These findings clearly indicate the critical importance of chronotypes to the emotional well-being of chronic psychiatric patients. Additional thought and research should explore possible chronotherapy interventions that will address this issue in patients.

Thrombolytic Therapy in Strokes: A Retrospective Clinical Data Analysis of 40 Patients in a 7-Year Period: The Experience of a Greek Internal Medicine Department

Stroke is one of the main causes of mortality and disability in developed countries. In acute ischemic stroke, the standard treatment is recombinant tissue plasminogen activator (rt-PA). The benefits of the treatment depend on the time of administration, the earlier it is administered, the greater its benefit. There are limited studies on the retrospective outcome of thrombolytic therapy in patients with acute ischemic stroke outside of clinical trials. The present retrospective study aimed to analyze the clinical data of 40 patients over 7 years who were hospitalized with acute ischemic stroke at the AHEPA University Hospital in Greece. From January 2013 to December 2020, 40 patients with acute ischemic stroke were admitted and treated. Computed tomography (CT) was performed at 24 h after thrombolytic treatment or earlier in case of neurological worsening. The hospital had 3 months follow-up at the stroke clinic and data consisting of the National Institute of Health Stroke Scale (NIHSS), functional outcome assessed by modified Rankin Scale (mRS) and mortality were reviewed in the medical records from the stroke clinic. The clinical outcome of functional independence defined by the modified Rankin Scale (mRS) ≤ 2 at 3 months was evaluated. Safety outcomes were in-hospital mortality, mortality at 3 months, and symptomatic intracerebral hemorrhage (sICH) defined by the Safe Implementation of Thrombolysis in Stroke-Monitoring Study (SITS-MOST) criteria. The main finding of the present study, that there was an overall reduction in the NIHSS scale after thrombolysis, proves that the patients showed improvement after performing thrombolysis. Consequently, from the total of 40 thrombolysis performed at the clinic, it can be concluded that most patients had a good outcome.

Clinical Characteristics and Risk Factors for Bloodstream Infections in Children with Cancer: A Report from a Pediatric Hematology Oncology Unit.

Infections are a major cause of morbidity and mortality in children with haematologic malignancies and solid tumors as well as those undergoing hematopoietic stem cell transplantation (HSCT). The purpose of our study was to record the epidemiological characteristics and outcomes of bacteremias, focusing on pathogens, as well as risk factors and mortality rates in patients of a pediatric hematology-oncology unit from Northern Greece. A retrospective analysis was conducted, which included all positive blood cultures from pediatric hematology oncology patients aged from 1 to 16 years old admitted to the Pediatric and Adolescent Hematology Oncology Unit of AHEPA University Hospital of Thessaloniki between January 2014 and December 2018. Data were collected from patients' printed and electronic medical records. 73 episodes of bacteremias were identified (41% male and 32% female with a ratio of 1.28:1; median age 6.5 years; 13.7% solid tumor, 72.6% acute lymphoblastic leukemia, 13.7% acute myeloid leukemia, and 95.8% with an indwelling permanent catheter). 49.3% of the isolates were Gram-positive bacteria and 50.7% Gram-negative, and the ratio of Gram-negative to Grampositive was 1.02. Coagulase-negative staphylococci were most frequent (39.7%), followed by E. coli (17.8%) and Klebsiella pneumoniae (17.8%). Out of all Gram-negatives, 13.5% carbapenemase producers and 8.1% ESBL-producers were found. In relation to Gram-positive, 79.3% were identified as methicillin-resistant CoNS. During the study period, 10.9% of indwelling catheters were removed, and 2.73% of episodes resulted in ICU transfer. The 3-month mortality rate was 8.2%. This study demonstrated an almost equal distribution of Gram-positive and Gramnegative bacteremias in total in this population but with an increase in the isolation of Grampositive bacteria over the last years, which is consistent with other similar studies in this patient group. Knowledge of the local epidemiology and bacterial antimicrobial resistance is important to prevent and timely treat these life-threatening infections in immunocompromised pediatric oncology patients.

The first positive evidence that training improves triage decisions in Greece: evidence from emergency nurses at an Academic Tertiary Care Emergency Department

BackgroundTriage refers to the process of patient prioritisation in the emergency department (ED). This is based on the severity of the patient’s illness and is performed by emergency nurses (ENs). This has a pivotal role in ensuring patient safety and in ensuring that the ED operates smoothly – so continuous and accurate training are essential. As Emergency Nursing has been formally established in Greece since 2019, it is of the uppermost importance that all Greek ENs should be trained in the use of a standardised triage system. The present study aimed to evaluate the effect of triage training of ENs in the use of the Swiss Triage System (STS) after an intervention of one week.MethodsThe effect of triage training was studied experimentally by comparing performance before and one week after training. A sample of thirty-six ENs from the University Department of Emergency Medicine at AHEPA University Hospital took part. The role of training in triage by the STS was assessed by completing the same self-administered questionnaire before and after a 45-minute e-learning program (presentation video of STS but with simulation scenarios) which was available during the period of a week. The post-training test was taken 2 weeks later, after the training process.ResultsThe most promising finding was that there was a significant improvement in the number of correct answers after the training in triage (p<0.001). A significant improvement was also detected (p<0.001) in the questions that tested vigilance in providing safe health services by ENs, whereas there was no significant association between the number of correct answers and years of emergency experience or level of education, - either before or after the intervention.ConclusionsTriage training seems to successfully improve effective and efficient triage. To the best of our knowledge, this is the first study that has demonstrated that triage training has a significant positive impact on triage performance by ENs in Greece. It is planned to support these findings by real time studies in an ED.

Artificial intelligence-based mining of electronic health record data to accelerate the digital transformation of the national cardiovascular ecosystem: design protocol of the CardioMining study

IntroductionMining of electronic health record (EHRs) data is increasingly being implemented all over the world but mainly focuses on structured data. The capabilities of artificial intelligence (AI) could reverse the...

Emergencies in the COVID-19 Era: Less Attendances, More Admissions.

IntroductionHealthcare systems suffered a significant hit by the COVID-19 pandemic since the spring of 2020, and a need for major reorganization emerged. Along with the constant increase in COVID-19 cases, a significant drop in emergency attendances for non-COVID-19-related conditions was noted worldwide. We decided to document attendances in our hospital's emergency department during the first lockdown period in order to monitor this trend, compare it to data from other countries, and start monitoring the effects of this reduction in the years to come.Materials and methodsEmergency department attendances at AHEPA University Hospital, Thessaloniki, Greece, from March 10, 2020, to May 31, 2020, were documented and compared to the corresponding period in 2019. The data collected included the number of patients per specialty, severity upon admission, as well as the need for admission.ResultsWe found a 58% reduction in emergency department attendance during the studied period compared to the corresponding period in 2019 (p<0.0001). The reduction was more noticeable in ears, nose, throat (ENT), and ophthalmology attendances (75.7% and 78.1% reductions, respectively, p<0.001), but other specialties, such as cardiology and general surgery, were also significantly affected (60% and 63% reductions, respectively, p<0.001). However, the percentage of attendances that required admission increased significantly by 25-33% (p<0.001) during the lockdown, reflecting the higher severity of cases reaching the hospital.ConclusionDespite the obvious reduction in attendances during the COVID-19 pandemic, patients still suffer from serious conditions that require hospital admission. Therefore, hospitals need to be supported to also care for these patients. The long-term effects of avoiding hospital attendance need to be closely monitored.

Neuroimaging and Electroencephalographic Correlation in Patients with Transient Global Amnesia: Clinical Case Series.

Objective. To determine if there is any correlation between the electroencephalographic and neuroimaging findings in patients with Transient Global Amnesia (TGA). Methods: We retrospectively reviewed files of the First Department of Neurology of AHEPA University Hospital, including patients with a clinical diagnosis of TGA. Only patients who had the characteristic high signal in the temporal lobes in the DWI MRI and those who underwent electroencephalographic recording (EEG) were selected. Results: Out of 28 patients, 8 were selected. We found that 6 out of 8 patients (75%) who had imaging findings in DWI, in at least one medial temporal lobe, also had had intermittent slow theta waves on the electroencephalographic recording. Of these 6 patients, 3 (50%) had bilateral EEG findings, 2 patients (33,3%) only had findings on the left hemisphere and 1 (17%) had on the right hemisphere. 3 out of 6 patients (50%) had electroencephalographic dominance on the left, while 2 out of the 6 (33%) had on the right. In 2 patients with imaging findings in DWI no anomalies were demonstrated on EEG. In 3 out of 8 patients, both MRI and EEG findings correlated on the same side, while 1 patient had opposite findings, depending on which hemisphere the EEG anomalies dominated. Conclusions: There is no absolute matching between the DWI MRI and EEG findings in patients with the clinical diagnosis of TGA. However, there is some degree of correlation, when we focus on the focal dominance of the EEG anomalies, although not statistically significant.

Antibody response after two doses of the BNT162b2 vaccine among healthcare workers of a Greek Covid 19 referral hospital: A prospective cohort study

The global vaccination against SARS-CoV-2 has highlighted the need of assessing vaccines' immunogenicity against COVID-19. To evaluate humoral immunity induced by the BNT162b2 vaccine, we enrolled health care workers at AHEPA University Hospital of Thessaloniki, Greece to measure Anti-S SARS-CoV-2, anti-RBD SARS-CoV-2 and neutralizing antibodies. A total of 955 individuals with a median age of 50 years, were included in the study. Median values of antibodies were 1947.27 BAU/mL (Abbott SARS-CoV-2 IgG II Quant), 2064.98 BAU/mL (MAGLUMI SARS-CoV-2 S-RBD IgG) and 2464.63 IU/mL (MAGLUMI SARS-CoV-2 Neutralizing Antibodies). Individuals previously infected had greater antibody responses than infection naive ones and a 7-fold higher neutralizing antibodies titre. Antibodies degreased by age but not sex. Spearman's correlation coefficient among the three assays ranged from 0.903 to 0.969.The BNT162b2 vaccine was highly immunogenic in our cohort. Further research is needed to evaluate the vaccine's immunogenicity through time as well as in different populations.

Correlation of Serum Acylcarnitines with Clinical Presentation and Severity of Coronary Artery Disease.

Recent studies support that acylcarnitines exert a significant role in cardiovascular disease development and progression. The aim of this metabolomics-based study was to investigate the association of serum acylcarnitine levels with coronary artery disease (CAD) severity, as assessed via SYNTAX Score. Within the context of the prospective CorLipid trial (NCT04580173), the levels of 13 circulating acylcarnitines were accurately determined through a newly developed HILIC-MS/MS method in 958 patients undergoing coronary angiography in the AHEPA University Hospital of Thessaloniki, Greece. Patients presenting with acute coronary syndrome had significantly lower median acylcarnitine C8, C10, C16, C18:1 and C18:2 values, compared to patients with chronic coronary syndrome (p = 0.012, 0.007, 0.018, 0.011 and <0.001, respectively). Among CAD subgroups, median C5 levels were significantly decreased in unstable angina compared to STEMI (p = 0.026), while median C10, C16, C18:1 and C18:2 levels were higher in stable angina compared to STEMI (p = 0.019 p = 0.012, p = 0.013 and p < 0.001, respectively). Moreover, median C2, C3, C4 and C8 levels were significantly elevated in patients with diabetes mellitus (p < 0.001, <0.001, 0.029 and 0.011, respectively). Moreover, short-chain acylcarnitine C2, C4, C5 and C6 levels were elevated in patients with heavier calcification and lower left ventricular ejection fraction (LVEF) % (all p-values less than 0.05). With regard to CAD severity, median C4 and C5 levels were elevated and C16 and C18:2 levels were reduced in the high CAD complexity group with SYNTAX Score > 22 (p = 0.002, 0.024, 0.044 and 0.012, respectively), indicating a potential prognostic capability of those metabolites and of the ratio C4/C18:2 for the prediction of CAD severity. In conclusion, serum acylcarnitines could serve as clinically useful biomarkers leading to a more individualized management of patients with CAD, once further clinically oriented metabolomics-based studies provide similar evidence.

A Risk-Stratification Machine Learning Framework for the Prediction of Coronary Artery Disease Severity: Insights From the GESS Trial.

Our study aims to develop a data-driven framework utilizing heterogenous electronic medical and clinical records and advanced Machine Learning (ML) approaches for: (i) the identification of critical risk factors affecting the complexity of Coronary Artery Disease (CAD), as assessed via the SYNTAX score; and (ii) the development of ML prediction models for accurate estimation of the expected SYNTAX score. We propose a two-part modeling technique separating the process into two distinct phases: (a) a binary classification task for predicting, whether a patient is more likely to present with a non-zero SYNTAX score; and (b) a regression task to predict the expected SYNTAX score accountable to individual patients with a non-zero SYNTAX score. The framework is based on data collected from the GESS trial (NCT03150680) comprising electronic medical and clinical records for 303 adult patients with suspected CAD, having undergone invasive coronary angiography in AHEPA University Hospital of Thessaloniki, Greece. The deployment of the proposed approach demonstrated that atherogenic index of plasma levels, diabetes mellitus and hypertension can be considered as important risk factors for discriminating patients into zero- and non-zero SYNTAX score groups, whereas diastolic and systolic arterial blood pressure, peripheral vascular disease and body mass index can be considered as significant risk factors for providing an accurate estimation of the expected SYNTAX score, given that a patient belongs to the non-zero SYNTAX score group. The experimental findings utilizing the identified set of important risk factors indicate a sufficient prediction performance for the Support Vector Machine model (classification task) with an F-measure score of ~0.71 and the Support Vector Regression model (regression task) with a median absolute error value of ~6.5. The proposed data-driven framework described herein present evidence of the prediction capacity and the potential clinical usefulness of the developed risk-stratification models. However, further experimentation in a larger clinical setting is needed to ensure the practical utility of the presented models in a way to contribute to a more personalized management and counseling of CAD patients.

Does COVID-19 Clinical Status Associate with Outcome Severity? An Unsupervised Machine Learning Approach for Knowledge Extraction.

Since the beginning of the COVID-19 pandemic, 195 million people have been infected and 4.2 million have died from the disease or its side effects. Physicians, healthcare scientists and medical staff continuously try to deal with overloaded hospital admissions, while in parallel, they try to identify meaningful correlations between the severity of infected patients with their symptoms, comorbidities and biomarkers. Artificial intelligence (AI) and machine learning (ML) have been used recently in many areas related to COVID-19 healthcare. The main goal is to manage effectively the wide variety of issues related to COVID-19 and its consequences. The existing applications of ML to COVID-19 healthcare are based on supervised classifications which require a labeled training dataset, serving as reference point for learning, as well as predefined classes. However, the existing knowledge about COVID-19 and its consequences is still not solid and the points of common agreement among different scientific communities are still unclear. Therefore, this study aimed to follow an unsupervised clustering approach, where prior knowledge is not required (tabula rasa). More specifically, 268 hospitalized patients at the First Propaedeutic Department of Internal Medicine of AHEPA University Hospital of Thessaloniki were assessed in terms of 40 clinical variables (numerical and categorical), leading to a high-dimensionality dataset. Dimensionality reduction was performed by applying a principal component analysis (PCA) on the numerical part of the dataset and a multiple correspondence analysis (MCA) on the categorical part of the dataset. Then, the Bayesian information criterion (BIC) was applied to Gaussian mixture models (GMM) in order to identify the optimal number of clusters under which the best grouping of patients occurs. The proposed methodology identified four clusters of patients with similar clinical characteristics. The analysis revealed a cluster of asymptomatic patients that resulted in death at a rate of 23.8%. This striking result forces us to reconsider the relationship between the severity of COVID-19 clinical symptoms and the patient’s mortality.

Clonal outbreak caused by VIM-4-producing Proteus mirabilis in a Greek tertiary-care hospital

Carbapenem-resistant Enterobacterales have become a major public-health issue worldwide. Here we report an outbreak caused by a clonal multidrug-resistant Proteus mirabilis strain producing VIM-4 metallo-β-lactamase (MBL) and TEM-2 β-lactamase in a Greek tertiary-care hospital. From July 2015 to February 2016, 27 imipenem-resistant P. mirabilis isolates were recovered from 14 patients hospitalised in two intensive care units (ICUs) and the internal medicine department in AHEPA University Hospital, Thessaloniki. The isolates were either susceptible or resistant to meropenem and were resistant to all remaining β-lactams except aztreonam. Phenotypic and molecular analysis revealed that all of the isolates harboured a blaVIM-4 MBL gene. Resistome analysis of a representative isolate showed the presence of an IncQ1 plasmid harbouring the blaVIM-4 carbapenemase and blaTEM-2 β-lactamase genes among resistance genes coding for resistance to β-lactams, aminoglycosides, trimethoprim, sulfonamides and lincosamides. Genotyping by pulsed-field electrophoresis (PFGE) revealed that the isolates were epidemiologically related. After recovery of the index carbapenemase-producing P. mirabilis clinical isolate, infection control measures were intensified in the affected departments. Rectal sampling for carbapenem-resistant bacteria was initiated on a weekly basis among patients admitted to the general ICU. The outbreak was finally interrupted 6 months later in February 2016. This is the first documentation of the blaVIM-4 MBL gene in P. mirabilis as well as the first hospital outbreak caused by a MBL-producing P. mirabilis strain.

Rationale and design of a prospective, observational study for the QUantitative EStimation of Thrombus burden in patients with ST-Elevation Myocardial Infarction using micro-computed tomography: the QUEST-STEMI trial

BackgroundAlthough the presence of thrombus in patients with ST-elevation myocardial infarction (STEMI) has been linked to adverse outcomes, routine thrombus aspiration has not been proven effective. A potential explanation is that these patients should be risk-stratified. Traditional clinical, laboratory and angiographic parameters used in clinical trials have been proven inadequate to classify patients. Aspirated thrombotic material characteristics might be an additional important parameter that has not yet been addressed. In this report, we aim to describe a methodological analysis of thrombus aspirated from coronary arteries during primary PCI using micro-Computed Τomography (micro-CT). These data will be combined with traditional factors to develop a risk-stratification system with high discriminative power for these patients.MethodsEighty-seven patients with STEMI undergoing thrombus aspiration in AHEPA University Hospital, Greece, will be enrolled in the study. The first patient was enrolled in June 2018. After being aspirated, thrombi are preserved in formalin and their volume and density are calculated with micro-CT. Micro-CT allows us to create 3D models of thrombi from a series of x-ray projection images. These models are further analyzed to find the volume and density of extracted thrombi and to assess potential differences in their structure. Association of these variables with clinical parameters and angiographic outcomes will be explored.DiscussionQUEST-STEMI is-to our knowledge-the first study of volumetric coronary thrombus assessment by micro-CT. This method could be used in larger, clinically-oriented trials to help stratify patients with thrombus burden according to their risk for adverse outcomes.Trial registrationQUEST-STEMI trial ClinicalTrials.gov number: NCT03429608 Date of registration: February 12, 2018. The study was prospectively registered (registered prior to enrollment of the first participant).

Hospital outbreak due to a Klebsiella pneumoniae ST147 clonal strain co-producing KPC-2 and VIM-1 carbapenemases in a tertiary teaching hospital in Northern Greece

Here we present the characteristics of a large outbreak caused by a clonal Klebsiella pneumoniae strain producing both KPC-2 and VIM-1 carbapenemases in a tertiary teaching hospital. Between January 2013 and January 2015, 45 carbapenem-resistant K. pneumoniae isolates that gave a positive modified Hodge test and were phenotypically suspected of metallo-β-lactamase (MBL) and K. pneumoniae carbapenemase (KPC) co-production were recovered from 25 patients hospitalised in AHEPA University Hospital (Thessaloniki, Greece). All of the patients were hospitalised in the three intensive care units of the hospital and 17 (68%) of them developed bloodstream infections; the overall mortality of the patients involved in the outbreak was 48% (12/25). Molecular testing verified that all 45 K. pneumoniae isolates co-harboured blaKPC-2 and blaVIM-1 genes and were associated with OmpK35 deficiency and OmpK36 porin loss. The blaTEM-1 gene was also present in 18 isolates. Pulsed-field gel electrophoresis (PFGE) clustered all of the isolates into a single clonal type, and multilocus sequence typing (MLST) assigned them to the emerging high-risk ST147 clonal lineage. Following recognition of the outbreak, infection control measures were implemented in the affected areas. The outbreak continued for ca. 2 years and since then only sporadic cases of K. pneumoniae harbouring both carbapenemases have been detected.

West Nile Virus Seroprevalence and Behavioral Risks in HIV-1 Infected Individuals, Northern Greece, 2011

This study sought to assess the West Nile Virus (WNV) seroprevalence and behavioral risk factors for WNV infection in HIV-1 infected individuals in Northern Greece in 2011. We prospectively enrolled 91 HIV-1 consecutive patients followed up in the HIV clinic of the AHEPA University Hospital in the period from November to December 2011. Serum samples were tested for the presence of WNV IgG antibodies. All subjects were administered a standardized questionnaire to evaluate for risk factors for WNV infection. WNV IgG antibodies were detected in three subjects (3.3%, 95% CI 0.7-9.3%), two of whom were of African origin. The prevalence of WNV antibodies in HIV patients of Greek origin was 1.2% (95% CI: 0.03% - 6.3%). In the sample surveyed, 53.6% (95% CI: 42.4% to 64.5%) were aware of WNV prevention measures; 2.2% reported no implementation of prevention measures, whereas 46.1% implemented at least three measures. Approximately one half of the patients reported outdoor activities for more than two hours from dusk to dawn. None of the IgG-positive patients reported any symptoms compatible with WNV disease during the season at risk. Among native Greek HIV patients, the WNV seroprevalence is 1.2%. A considerable proportion of patients was aware of WNV prevention measures and implemented some of these. HIV patients and other categories of immunocompromised patients are at increased risk of neuroinvasive disease, and widespread implementation of prevention measures should be strongly encouraged in this patient population.

Comparison between the combination of gabapentin, ketamine, lornoxicam and local ropivacaine and each of these drugs alone for pain after laparoscopic cholecystectomy: a randomized trial

1424 Military Hospital of Thessaloniki, Dept of Anaesthesiology & Intensive Care, Thessaloniki, Greece,2AHEPA University Hospital, Dept of Anaesthesiology & Intensive Care, Thessaloniki, Greece

Renin-angiotensin system blockade and exercise-induced increase in aortic stiffness.

In physiological conditions, the cushioning function of central conduit arteries transforms the cyclic high-flow and pressure oscillations in the ascending aorta into continuous and low-pressure blood flow at the level of microcirculation. Aging and elevated blood pressure (BP) induces structural and functional changes in arterial wall viscoelastic properties, resulting in arterial stiffening. The latter is reflected in progressive impairment of the cushioning function of central arteries and is typically associated with the development of isolated systolic hypertension and left ventricular hypertrophy. Importantly, prospective cohort studies have demonstrated that arterial hardening represents a strong and independent predictor of all-cause and cardiovascular mortality in various diseased populations, including patients with essential hypertension. Current guidelines on the management of arterial hypertension recommend regular physical activity as a major nonpharmacologic treatment approach towards BP lowering and cardiovascular risk reduction. In contrast, several lines of evidence from clinical studies suggest that acute high-intensity exercise can transiently elevate the risk of fatal and nonfatal cardiovascular events, mainly in prediposed individuals with substrate of structural cardiovascular disease. The mechanistic background of this deleterious impact of acute exercise on the cardiovascular system remains largely unclear. Activation of the sympathetic nervous system, aggravation of oxidative stress, platelet activation, impaired coagulation and fibrinolysis, and acute deterioration of large artery elasticity represent some of the mechanisms that have been proposed to be involved. It has to be noted that the type, frequency, duration, and intensity of physical exercise, play an important role in the exercise-induced alterations on the cardiovascular system. In this regard, previous clinical studies that investigated the effects of acute exercise on arterial elasticity, provide variable results. Some studies have shown high-intensity exercise to be associated with an acute increase in stiffness of central conduit arteries in healthy individuals. In other clinical studies, maximal aerobic exercise was found not to acutely affect large artery elasticity in young healthy patients. In contrast to the above, other investigators observed a sustained and prolonged improvement in compliance of peripheral muscular-type arteries and no change in elasticity of central conduit arteries after submaximal acute exercise in healthy patients. In this issue of The Journal of Clinical Hypertension, Gkaliagkousi and coworkers add important information to our knowledge, in this area, by reporting the results of a clinical study that explored acute changes in aortic stiffness after a high-intensity aerobic exercise test: (1) in untreated hypertensive compared with normotensive individuals, and (2) in hypertensive patients after 3 months of treatment with the angiotensin receptor blocker (ARB), valsartan. The study included 25 young patients with never-treated, newly diagnosed, stage I hypertension and 15 ageand sexmatched healthy volunteers. The investigators performed a careful workup of patients prior to study enrollment, excluding patients with secondary causes of hypertension and patients with white-coat or masked hypertension by performing 24-hour ambulatory BP monitoring. Arterial stiffness was assessed by measuring carotid to femoral pulse wave velocity (cf-PWV) with the use of the Sphygmocor device (AtCor Medical, West Ryde, Australia) at maximal exercise and at 10, 30, and 60 minutes after the completion of a treadmill exercise test. At baseline exercise test, significant elevations in systolic BP were noted at maximal exercise in both, hypertensive patients and healthy controls, which returned to pre-exercise levels after 10 and 30 minutes of recovery, respectively. In contrast, diastolic BP was not significantly different during acute high-intensity exercise, in both study groups. With regards to exercised-induced changes in aortic stiffness, cf-PWV was significantly elevated at maximal exercise in the group of hypertensive patients but not in the group of healthy controls. Of importance, despite the post-exercise reduction in systolic BP levels, the increase in cf-PWV persisted, even after 30 minutes of recovery in hypertensive patients. As expected, systolic BP and cf-PWV levels at all 5 timepoints of the baseline exercise test were significantly higher in hypertensive patients than in controls. After completion of the baseline test, 15 hypertensive participants who had indications to receive BP-lowering therapy according to guidelines were included in a subsequent interventional phase of the study to receive treatment with valsartan 160 mg daily for 3 months. Valsartan treatment resulted in significant reductions in both office and ambulatory BP and all treated hypertensive patients achieved adequate BP control at study Address for correspondence: Pantelis E. Zebekakis, MD, PhD, Section of Nephrology and Hypertension, 1st Department of Medicine, AHEPA University Hospital, St. Kiriakidi 1, GR54636, Thessaloniki, Greece E-mail: pzebeka@med.auth.gr

Wavelet-based analysis of P waves identifies patients with lone atrial fibrillation: A cross-sectional pilot study

atrial fibrillation: A cross-sectional pilot study George Dakos ⁎⁎, Yiannis S. Chatzizisis ⁎, Dimitrios Konstantinou , Ioanna Chouvarda , Dimitrios Filos , Stylianos Paraskevaidis , Lilian Mantziari , Nicos Maglaveras , Haralambos Karvounis , Ioannis Styliadis , Vassilios Vassilikos a,e a First Department of Cardiology, AHEPA University Hospital, Aristotle University Medical School, Thessaloniki, Greece b Cardiovascular Division, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, USA c Laboratory of Medical Informatics, Aristotle University Medical School, Thessaloniki, Greece d Department of Cardiology, Electrophysiology Unit, Royal Brompton Hospital, London, UK e Third Department of Cardiology, Hippokrateion University Hospital, Aristotle University Medical School, Thessaloniki, Greece