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Objective In 2008, the radiofrequency ablation (RFA) procedures registry of the Hellenic Society of Cardiology was created. This online database allowed electrophysiologists around the country to input data for all performed ablation procedures. The aim of this study is to provide a thorough report and interpretation of the data submitted to the registry between 2008 and 2018. Methods In 2008, a total of 27 centers/medical teams in 24 hospitals were licensed to perform RFA in Greece. By 2018, the number had risen to 31. Each center was tasked with inserting their own data into the registry, which included patient demographics (anonymized), type of procedure and technique, complications, and outcomes. Results A total of 18587 procedures in 17900 patients were recorded in the period of 2008-2018. By 2018, slightly more than 70% of procedures were performed in 7 high-volume centers (>100 cases/year). The most common procedure since 2014 was atrial fibrillation ablation, followed by atrioventricular nodal reentry tachycardia ablation. Complication rates were low, and success rates remained high, whereas the 6-month relapse rates declined steadily. Conclusion This online RFA registry has proved that ablation procedures in Greece have reached a very high standard, with results and complication rates comparable to European and American standards. Ablation procedures for atrial fibrillation are increasing constantly, with it being the most common intervention over the last 6-year period, although the absolute number of procedures still remains low, compared to other European countries.

Sensors play a vital role in the industry transformation. Commercial sensors such as force sensors have limited options in shapes, stiffness, measuring ranges, etc. Customized force sensors optimized for the production environment can greatly increase the integration workflow and avoid the trade-off in design freedom of using commercial sensors. 3D printing, as a rapid prototyping technology, offers great potential in fabricating force sensors customized to a specific application. However, most of the existing 3D printed force sensors are limited to one-directional sensing, while most of them use materials developed in-house. In this study, a fully 3D printed force sensor using commercial conductive 3D printing materials is presented. By utilizing the resistance change when under load, the sensor can estimate the applied force in multiple directions. The resistive performance of the prototype 3D printed force sensor is first characterized and then validated in a case study.

Η ερευνητική περιοχή που εξετάζεται στην παρούσα διδακτορική διατριβή καλύπτει θέματα ανάλυσης, μοντελοποίησης και ελέγχου της λειτουργίας του Τεχνητού Πνευματικού Μυός (ΤΠΜ) ως μονάδα ενεργοποίησης καθώς και ως μέσο ενεργοποίησης πρότυπης πειραματικής διάταξης.Η ερευνητική πορεία ξεκινά με τη βιβλιογραφική αναζήτηση και τη μελέτη άρθρων σχετιζόμενων με θεωρητικές προσεγγίσεις μοντελοποίησης των ΤΠΜ, την ανασκόπηση των στρατηγικών που έχουν αναπτυχθεί και εφαρμοστεί για τον έλεγχο των βασικών χαρακτηριστικών του ΤΠΜ, καθώς και την παρουσίαση των σημαντικότερων εφαρμογών που έχουν αναπτυχθεί και δημοσιευθεί έως σήμερα, και κάνουν χρήση του συγκεκριμένου πνευματικού μέσου ενεργοποίησης.Στα πλαίσια μελέτης της στατικής και δυναμικής λειτουργίας του ΤΠΜ, πραγματοποιήθηκαν εκτενή πειράματα για την αναγνώριση των στοιχείων που συνθέτουν τη δυναμική εξίσωση που περιγράφει τα χαρακτηριστικά λειτουργίας του, αναπτύσσοντας και κάνοντας χρήση ειδικής πειραματικής διάταξης για την ανάλυση των μη-γραμμικοτήτων που περιγράφουν τις καταστάσεις λειτουργίας του ενεργοποιητή αυτού. Τα αποτελέσματα χρησιμοποιήθηκαν για την προσομοίωση της διαδοχικής κίνησης, στο επίπεδο, πολλαπλών σειριακά συνδεδεμένων ΤΠΜ. Ακολούθησε περαιτέρω μελέτη των μη-γραμμικών φαινομένων που περιγράφουν τη λειτουργία του ΤΠΜ, επικεντρώνοντας την ερευνητική προσοχή πάνω στα φαινόμενα υστέρησης που χαρακτηρίζουν τις βασικές ιδιότητές του, ενώ ακολούθησε εκτενής πειραματική μελέτη των φαινομένων που προκαλούν την αύξηση της θερμοκρασίας του ΤΠΜ κατά τη διαρκή λειτουργία του. Επιπρόσθετα, μελετήθηκε πειραματικά η επίδραση των θερμικών αλλαγών στη λειτουργία του ΤΠΜ, με σκοπό τη συμπερίληψή της στο στατικό μοντέλο που συνδέει τα βασικά στοιχεία του συστήματος (πίεση, μετατόπιση, ελκτική δύναμη).Στο πλαίσιο επέκτασης του θεωρητικού υπόβαθρου μοντελοποίησης του ΤΠΜ, εξετάστηκε η επίδραση της θερμοκρασιακής μεταβολής στα λειτουργικά χαρακτηριστικά του ΤΠΜ και ενσωματώθηκε στη στατική περιγραφή της λειτουργίας του κάνοντας θεωρητική χρήση του φαινομένου της Θερμικής Εξάπλωσης (Thermal Expansion). Το τροποποιημένο μοντέλο στατικής λειτουργίας του ΤΠΜ προσομοιώθηκε για λόγους ανάλυσης της αποτελεσματικότητας του στην εκτίμηση των χαρακτηριστικών του ΤΠΜ μέσω των θερμικών δεδομένων που συλλέχθηκαν κατά την πειραματική λειτουργία του υπό μελέτη ενεργοποιητή.Στην προσπάθεια θεωρητικής περιγραφής της δυναμικής λειτουργίας του ΤΠΜ, αναπτύχθηκε μία Τμηματικά Συσχετιζόμενη (Piecewise Affine) προσέγγιση μοντελοποίησης, όπου οι δυναμικές μη-γραμμικές εξισώσεις του προσεγγίζονται με διακοπτική εναλλαγή ανάμεσα σε γραμμικοποιημένα υποσυστήματα εκφρασμένα στο χώρο κατάστασης, τα οποία περιγράφουν τη δυναμική συμπεριφορά του ΤΠΜ σε διαφορετικές περιοχές λειτουργίας. Πραγματοποιήθηκε έλεγχος της απόδοσης του προσεγγιστικού μοντέλου μέσω προσομοιώσεων σε προγραμματιστικό περιβάλλον.Πάνω στην τμηματικά συσχετιζόμενη προσέγγιση της δυναμικής λειτουργίας του ΤΠΜ βασίστηκε η ανάπτυξη και εφαρμογή στρατηγικής Ελέγχου Πρόβλεψης Μοντέλου (Model Predictive Control). Μελέτες προσομοίωσης της συγκεκριμένης στρατηγικής για τον έλεγχο της μετατόπισης του ΤΠΜ ακολούθησε πειραματική εφαρμογή και αξιολόγηση της απόδοσης του ελέγχου υπό διαφορετικές συνθήκες επιλογής της διακοπτικής προσέγγισης μοντελοποίησης του ΤΠΜ αλλά και των δομικών παραμέτρων που συνθέτουν το βέλτιστο νόμο ελέγχου.Παράλληλα, αναπτύχθηκε στρατηγική ελέγχου Φραγμένου Βέλτιστου Ελέγχου Πεπερασμένου Χρόνου (Constrained Finite Time Optimal Control) χρησιμοποιώντας ως βάση την προαναφερθείσα τμηματικά συσχετιζόμενη προσέγγιση μοντελοποίησης, με σκοπό τη σύγκριση της απόδοσης και των χαρακτηριστικών ελέγχου με αυτή του Ελέγχου Πρόβλεψης Μοντέλου. Η αξιολόγηση της συμπεριφοράς του συστήματος κλειστού βρόχου και των χαρακτηριστικών που συνθέτουν τη συγκεκριμένη δομή πραγματοποιήθηκαν μέσω εκτενών πειραματικών μελετών.Για τον εμπλουτισμό των πειραματικών αποτελεσμάτων και τη συγκριτική μελέτη των παρουσιαζόμενων ελεγκτών, τα χαρακτηριστικά των εφαρμοζόμενων ελεγκτών εξετάστηκαν σε βάθος και συγκρίθηκαν εκτενώς μέσω πειραματικής εφαρμογής του κλασικού PID νόμου ελέγχου στην πειραματική διάταξη. Η ερευνητική πορεία συνέχισε με την προσαρμογή της αρχικής πειραματικής διάταξης ώστε να μελετηθεί η ανταγωνιστική λειτουργία δύο ή περισσότερων μυών καθώς και η δυναμική μελέτη της απόκρισης ενός ΤΠΜ κάνοντας χρήση των ανταγωνιστικών μυών ως εξωτερικό φορτίο. Ακολούθησε ανάπτυξη και εφαρμογή μιας στρατηγικής Προσαρμοστικού ελέγχου Εσωτερικού Μοντέλου (Internal Model Control) της μονής και της ανταγωνιστικής λειτουργίας των ΤΠΜ. Το σύστημα ελέγχου τροποποιήθηκε και βελτιώθηκε κάνοντας χρήση αναδρομικών ελαχίστων τετραγώνων για την αναγνώριση των παραμέτρων του προς έλεγχο συστήματος, δίνοντας στη δομή ελέγχου την απαραίτητη προσαρμοστικότητα στις μη-γραμμικές αλλαγές που συμβαίνουν κατά τη διάρκεια λειτουργίας των ΤΠΜ. Πραγματοποιήθηκαν εκτενή πειράματα για την επιβεβαίωση της σωστής λειτουργίας καθώς και εξέταση της σθεναρότητας και προσαρμοστικότητας του συγκεκριμένου νόμου ελέγχου.Ακόμα, μελετήθηκαν μη-γραμμικοί τρόποι ελέγχου της μονής και της ανταγωνιστικής λειτουργίας των ΤΠΜ ενώ, συγκεκριμένα, αναπτύχθηκε ένας Προηγμένος Μη-Γραμμικός PID νόμος ελέγχου (Advanced Non-linear PID Control) ο οποίος περιλάμβανε χαρακτηριστικά όπως δύο βαθμούς ελευθερίας, τετραγωνική προσαρμογή σφάλματος, τραπεζοειδή ολοκλήρωση και μερική παραγώγιση για γρήγορο, σθεναρό και ομαλό έλεγχο των ΤΠΜ. Πραγματοποιήθηκε πειραματική εφαρμογή του νόμου ελέγχου στη διάταξη μελέτης, η οποία επιβεβαίωσε την επιτυχή λειτουργία καθώς και τα πλεονεκτήματα του εφαρμοζόμενου ελεγκτή μέσω πειραματικής σύγκρισης με τον κλασικό PID νόμο ελέγχου.Τέλος, η ερευνητική πορεία ανάλυσης, μοντελοποίησης και ελέγχου των ΤΠΜ κατέληξε στο σχεδιασμό, τη μελέτη και τον έλεγχο ενός πρωτότυπου εξωσκελετικού μηχανισμού για την υποβοήθηση της κίνησης του ανθρώπινου καρπού, κάνοντας χρήση των ΤΠΜ ως μέσο ενεργοποίησης. Αναλύθηκαν οι στρατηγικές σχεδιασμού, μελετήθηκε η χρήση εναλλακτικών αισθητήριων συστημάτων για την κατάστρωση διαδεδομένων φυσιοθεραπευτικών στρατηγικών χρήσης ενώ πραγματοποιήθηκε πειραματικός έλεγχος της διάταξης κάνοντας χρήση του συμβατικού PID αλγορίθμου και του Προηγμένου Μη-Γραμμικού PID που αναπτύχθηκε στα πλαίσια της παρούσας διδακτορικής διατριβής.Τα ερευνητικά αποτελέσματα που προέκυψαν, παρουσιάστηκαν σε διεθνή επιστημονικά συνέδρια και περιοδικά, το σύνολο των οποίων παρουσιάζεται στο Παράρτημα.

Η παρούσα διατριβή ασχολήθηκε με το γενετικό υπόστρωμα της ισχαιμικήςκαρδιοπάθειας και την επιδημιολογία των παραγόντων καρδιαγγειακού κίνδυνουστον Ελληνικό πληθυσμό Για το σκοπό αυτό σχεδιάστηκε κι εκπονήθηκε maπολυκεντρική μελέτη σε εννιά καρδιολογικές κλινικές σε Αθήνα Πειραιά καιθεσσαλονίκη που συγκέντρωσε κλινικά και γενετικά δεδομένα απο 1749 ασθενείς ιχεοξυ έμφραγμα μυοκαρδίου (OEM) και 805 τυχαία επιλεγμένους ενήλικες απο τογενικό πληθυσμό που αποτέλεσαν την ομάδα των μαρτύρων Μελετήθηκαν ο I/Dπολυμορφισμός του γονίδιου του ΜΕΑ ο A/C πολυμορφισμός του γονίδιου των AT1 υποδοχέων της Αγγειοτασινης II ο Ile405VaI πολυμορφισμός του /ονιδιου τηςCETP και ο 894G—»Τ πολυμορφισμός του γονίδιου της ενδοθηλιακής συνθετασηςτου NO σε σχέση με την πιθανότητα εκδήλωσης αλΛ,α και την πρόγνωση του OEMΤα αποτεΑεσμαια έδειξαν οτι κανένας απο τους παραπάνω πoλυμopφισμoυc δενσυσχετίζεται με το OEM ανεξάρτητα απο τους μειςονες παράγοντες καρδιαγγειακούκίνδυνου Πολλά απο τα επι μέρους συμπεράσματα ήρθαν σε αντίθεση ιιεπροηγούμενες απόψεις για το ρολό των πολυμορφισμών αυτών ενω ενδιαφέρωνπαρουσίαζαν και τα κλινικά κι επιδημιολογικά δεδομένα των ασθενών πουμελετήθηκαν Απο τα αποτελέσματα αυτής της διδακτορικής διατριβής προέκυψαν Dπλήρεις δημοσιεύσεις και 24 ανακοινώσεις σε εθνικά και διεθνή συνέδριαι

We describe the case of a young patient with runs of repetitive monomorphic left ventricular tachycardia. He was diagnosed with verapamil-sensitive, idiopathic left ventricular tachycardia (ILVT) and underwent an electrophysiological study, in which dual atrioventricular (AV) nodal physiology was evident, with an AV nodal reentrant tachycardia (AVNRT) being easily and reproducibly induced. Both the AVNRT and the ILVT were successfully ablated using high-density electroanatomical mapping and an open-irrigation catheter. In conclusion, verapamil-sensitive ILVT might coexist with AVNRT. In case of invasive therapy, a thorough electrophysiological evaluation is mandatory to exclude or treat other co-existing reentrant supraventricular arrhythmias.

In this article, a soft exoskeletal glove is proposed for investigating the potential of utilizing Pneumatic Artificial Muscles (PAMs) for suppressing hand tremor of Essential Tremor (ET) patients. The glove setup is first presented from a conceptual point, which is focused on the dual investigation of applying local kinesthetic forces exerted via PAMs on the user's finger and on the metacarpal region. An experimental protocol is being derived incorporating a force controller adjusted for both investigated cases, while the efficiency of the proposed setup is extensively evaluated under various motion scenarios performed by an ET-diagnosed volunteer. QC 20220620Part of proceedings: ISBN 978-3-90714-402-2

This article establishes an Explicit Model Predictive Control (EMPC) scheme for controlling the adhesion of a climbing Vortex Robot (VR). The VR utilizes an Electric Ducted Fan (EDF) as the Vortex Actuator (VA), where the dynamics have been identified via an Autoregressive-Moving-Average with eXternal input (ARMAX) identification scheme. An explicit controller via the use of a Constraint Finite Time Optimal Control (CFTOC) approach is designed in an offline manner and implemented for the case of the VR, where the adhesion reference is provided by a static force model. The presented approach results in a lookup table realization that ensures overall system stability in all state transitions, while being able to accurately control the adhesion force for arbitrary setup orientations. The efficacy of the proposed control scheme is demonstrated through experimental results involving a moving test surface under random inclinations and robot orientations.

In this article, the critical adhesion force and achievable payload of a Vortex Actuator (VA) are analyzed under 3-DOF surface rotations. A model-based control scheme is later proposed, with the goal of maintaining VA adhesion when immobilized, while limiting the power consumption and counteracting disturbances leading to Center-of-Mass (CoM) variations. Finally, the model-based control scheme is experimentally evaluated with the VA prototype on a flat surface under linear motions and rotations, thus supporting the incorporation of the VA in Climbing Robots (CRs) for inspection and maintenance of both stationary and moving surfaces.

In this article, the potential of utilizing a commercially available Electric Ducted Fan (EDF) as a negative-pressure actuator for adhesion purposes is experimentally tested. To this purpose, a novel EDF-based Vortex Actuation System (VAS) is proposed and presented from a design, development and experimental evaluation perspective. The effect of different EDF design properties and design alterations to the actuation system is analyzed, for providing novel considerations on optimizing the adhesion efficiency of such a system.

Chios mastic gum (CMG) possesses anti-oxidant, anti-inflammatory, anti-atheromatic, lipid- and glucose-lowering properties. We evaluated the effects of CMG on cholesterol and fasting plasma glucose (FPG) levels of healthy volunteers.A prospective, randomized, placebo-controlled, pilot study.One hundred and seventy nine volunteers with total cholesterol levels200 mg/dl were randomized to four groups. Finally, 156 volunteers completed the follow-up period and were analysed: (1) control group (C, n = 23), receiving placebo; (2) total mastic (TM, n = 72) receiving daily a total dose of 1 g of crude CMG (330 mg capsules, tid); (3) polymer-free mastic (PFM, n = 33), receiving daily a total dose of 1 g of polymer free mastic (330 mg caps, tid); and (4) powder mastic (PM, n = 28), receiving daily a total dose of 2 g of crude CMG.After eight weeks, the TM group reduced total cholesterol by 11.5 mg/dl (p 0.05) and FPG by 4.5 mg/dl (p 0.05) adjusted for age, gender, BMI and baseline characteristics. The effect was stronger in overweight and obese patients (BMI 25), with an estimated mean reduction of total cholesterol by 13.5 mg/dl (p 0.05) and FPG by 5.1 mg/dl (p 0.05). Administration of PFM and PM resulted in no statistically significant alteration. No effect was observed on LDL, HDL, triglycerides, uric acid and CRP. No gastrointestinal, liver or renal adverse events were recorded.CMG has a significant lowering effect on total cholesterol and glucose levels of healthy volunteers, with excellent tolerance and no detectable side effects, especially in overweight and obese individuals.

BACKGROUND Current European Guidelines suggest the use of cardiovascular risk categories and also recommend using high-intensity statins for patients with acute coronary syndromes (ACS). OBJECTIVE We examined the risk of ACS patients prior to the event, as well as the overall use and intensity of statins. METHODS We enrolled 687 ACS patients (mean age 63 years, 78% males). Low-density lipoprotein cholesterol (LDL-C) levels upon admission were used to assess attainment of LDL-C targets. Patients were categorized as very high, high, moderate and low risk based on their prior to admission cardiovascular (CV) risk. We examined statin use and dosage intensity among patients discharged from the hospital. Patients were followed for a median period of 189 days. RESULTS The majority of the patients (n=371, 54%) were at very high CV risk prior to admission, while 101 patients were at high risk (15%), 147 (21%) moderate risk and 68 (10%) low risk. Interestingly, LDL-C target attainment decreased as the risk increased (p

In this article, a switching Model Predictive Controller (sMPC) scheme for the position control of a Pneumatic Artificial Muscle (PAM) is being presented. The control scheme is based on a constrained linear and PieceWise Affine (PWA) system model approximation that is able to capture the high nonlinearities of the PAM and improve the overall model accuracy, and is composed of: a) a feed-forward term regulating control input at specific reference set-points, and b) a switching Model Predictive Controller handling any deviations from the system’s equilibrium points. Extended simulation studies were utilized in order to investigate and evaluate the efficacy of the suggested controller in the positioning problem of a PAM.

Full or partial loss of function in the shoulder, elbow or wrist is an increasingly common ailment caused by various medical conditions like stroke, occupational and sport injuries, as well as a number of neurological conditions, which increases the need for the development and improvement of upper limb rehabilitation devices. In this article, the design and implementation of the EXOskeletal WRIST (EXOWRIST) prototype is presented. This novel robotic appliance’s motion is achieved via pneumatic artificial muscles, a pneumatic form of actuation possessing crucial attributes for the development of an exoskeleton that is safe, reliable, portable and low-cost. Furthermore, the EXOWRIST’s properties are presented in detail and compared to the recent wrist exoskeleton technology, while its two degrees-of-freedom movement capabilities (extension–flexion, ulnar–radial deviation) are experimentally evaluated via a PID-based control algorithm. Experimental results involving initial testing of the proposed exoskeleton on a healthy human volunteer for the preliminary evaluation of the EXOWRIST’s attributes are also presented.

In this paper, the positioning control problem of pneumatic muscle actuators (PMAs) is being considered. A two-degree-of-freedom nonlinear proportional-integral-derivative structure is being synthesized, providing ameliorated compensation of the PMAs' nonlinear hysteretic phenomena and advanced robustness through disturbance cancellation. Experimental studies are being utilized to prove the overall efficiency of the proposed control scheme with regard to set-point tracking performance for the position control of a single PMA, torsion angle control of a nonsymmetrical antagonistic PMA setup, and disturbance rejection in both single and antagonistic control scenarios.

In this article, a switching Model Predictive Controller (sMPC) for a pneumatic artificial muscle (PAM) is presented. The control scheme is based on a switching PieceWise Affine (PWA) system model approximation that is able to capture the high nonlinearities of the PAM, while improving the overall model accuracy, and is composed of: (a) a feed-forward term regulating control input at specific reference set-points, and (b) a switching Model Predictive Controller handling any deviations from the system's equilibrium points. Extended experimental studies are being presented that prove the overall scheme's efficiency.

An increased prevalence of coronary artery ectasia (CAE) and a low frequency of diabetes mellitus have been reported in patients with abdominal aortic aneurysm (AAA). The prevalence of diabetes was studied in 190 patients with CAE in comparison with 341 age- and gender-matched patients with coronary artery disease alone. Diabetes mellitus was found to be independently but inversely associated with CAE (relative risk 0.603, 95% confidence interval 0.375 to 0.960, p = 0.037), thus resembling the relation between diabetes and AAA.

The Pneumatic Artificial Muscle (PAM) is a highly non-linear form of actuation that is characterized by a decrease in the actuating length when pressurized. Its non-linear nature and time-varying parameters cause difficulties in modelling their characteristics and designing controllers for high-performance positioning systems. In this article, the control problem of a PAM is considered. A constrained linear and PieceWise Affine (PWA) system model approximation is utilized and a controller composed of: a) a feedforward term regulating control input at specific setpoints, and b) a Constrained Finite Time Optimal Controller (CFTOC) handling any deviations from the system’s equilibrium points is synthesized. Simulation studies are used to investigate the efficacy of the suggested controller. Godkänd; 2012; 20120527 (geonik)

The aim of this article is to provide a survey on the most popular modeling approaches for Pneumatic Muscle Actuators (PMAs). PMAs are highly non-linear pneumatic actuators where their elongation is proportional to the interval pressure. During the last decade, there has been an increase in the industrial and scientific utilization of PMAs, due to their advantages such as high strength and small weight, while various types of PMAs with different technical characteristics have been appeared in the literature. This article will: a) analyse the PMA's operation from a mathematical modeling perspective, b) present their merits and drawbacks of the most common PMAs, and c) establish the fundamental basis for developing industrial applications and conducting research in this field. Godkänd; 2012; 20111206 (geonik)

The aim of this article is to present a survey on applications of Pneumatic Artificial Muscles (PAMs). PAMs are highly non-linear pneumatic actuators where their elongation is proportional to the interval pressure. During the last decade, there has been a significant increase in the industrial and scientific utilization of PAMs due to their advantages such as high strength and small weight, while various types of PAMs with different technical characteristics have been appeared in the relative scientific literature. This article will summarize the key enabling applications in PAMs that are focusing in the following areas: a) Biorobotic, b) Medical, c) Industrial, and d) Aerospace applications.

The aim of this article is to present a dynamic analysis and a cascade movement simulation of a Pneumatic Muscle Actuator (PMA). PMAs are highly non–linear pneumatic actuators where their elongation are proportional to the interval pressure. Their non–linear characteristics and the property of the hysteresis are posing several difficulties in simulating these pneumatic actuators and to obtain a comprehension of the PMA’s physical movement. In this article a novel detailed modeling, based on hardware in the loop simulationstudies, capable to describe the dynamic characteristic of the PMA and a detailed simulation environment for studying the cascade movement of PMAs will be presented. Validerad; 2012; Bibliografisk uppgift: G. Andrikopoulos, J. Arvanitakis, G. Nikolakopoulos and S. Manesis, "Dynamic Analysis and Cascade Movement Simulation of a Pneumatic Muscle Actuator", accepted for publication in the IASTED International Conference on Modeling, Simulation and Identification, November 7-9, Pittsburgh, USA, 2011.; 20111212 (ysko), QC 20220620

AIMS: To compare the treatment and outcomes of myocardial infarction patients in hospitals with and without catheterization laboratory. METHODS AND RESULTS: The Hellenic Infarction Observation Study was a countrywide registry of acute myocardial infarction, conducted during 2005-2006. The registry enrolled 1840 patients with myocardial infarction from 31 hospitals with a proportional representation of all types of hospitals and of all geographical areas. Out of these patients, 645 (35%) were admitted in 11 hospitals with and 1195 (65%) in 20 hospitals without catheterization laboratory. Patients admitted in hospitals with catheterization laboratory in comparison with patients admitted in hospitals without were younger (66+/-14 vs. 68+/-13, P1 22 vs. 23%). Reperfusion rates for ST-segment elevation myocardial infarction were 67% (43% lytic, 24% primary percutaneous coronary interventions) versus 56% (55% lytic, 1% percutaneous coronary interventions; P

The aim of this study was to evaluate the validity of an echocardiographic method of automatic boundary detection (ABD) in the assessment of the degree of atrial dysfunction in patients who had undergone external or internal cardioversion for idiopathic atrial fibrillation.The study population included 31 patients (mean age 48 +/- 6.5 years) with idiopathic atrial fibrillation. The patients were randomised into two groups: Group 1 (14 patients, 8 +/- 3.13 joules), where internal cardioversion was applied, and Group 2 (17 patients, 200-360 joules), where external cardioversion was used for restoration of sinus rhythm. During the following 24 hours the ABD method was used in both groups to assess the following functional indices for both the left and the right atrium: a) total fractional change of atrial area (delta1), b) passive change of atrial area (delta2), c) change of atrial area due to atrial contraction (delta3) and d) index of % atrial expansion (delta4).All patients in both groups were successfully cardioverted (100%, p: NS). Post-cardioversion indices delta1-delta4 for both left and right atria did not differ between the 2 groups (p:NS). A negative correlation was found between left atrial function as assessed by ABD and the mean energy in joules delivered through the catheter in each patient for successful cardioversion (r = -0.55 to r = -0.67 and p = 0.04 to p = 0.01). However, no relevant correlations were found for the right atrium (p:NS).1) The atrial dysfunction which follows the cardioversion of idiopathic atrial fibrillation (atrial stunning) is not related to the type of cardioversion (internal or external). 2) The higher the amount of energy delivered during internal cardioversion, the greater the degree of left atrial dysfunction observed.

Pseudoexfoliation (PEX) syndrome is a well-recognized late-onset disease caused by a generalized fibrillopathy. It is linked to a broad spectrum of ocular complications including glaucoma and perioperative problems during cataract surgery. Apart from the long-known intraocular manifestations, PEX deposits have been found in a variety of extraocular locations and they appear to represent a systemic process associated with increased cardiovascular and cerebrovascular morbidity. However, as published results are inconsistent, the clinical significance of the extraocular PEX deposits remains controversial. Identification of PEX deposits in the heart and the vessel wall, epidemiologic studies, as well as, similarities in pathogenetic mechanisms have led to the hypothesis of a possible relation between fibrillar material and cardiovascular disease. Recent studies suggest that PEX syndrome is frequently linked to impaired heart and blood vessels function. Systemic and ocular blood flow changes, altered parasympathetic vascular control and baroreflex sensitivity, increased vascular resistance and decreased blood flow velocity, arterial endothelial dysfunction, high levels of plasma homocysteine and arterial hypertension have all been demonstrated in PEX subjects. Common features in the pathogenesis of both atherosclerosis and PEX, like oxidative stress and inflammation and a possible higher frequency of abdominal aorta aneurysm in PEX patients, could imply that these grey-white deposits and cardiovascular disorders are related or reflect different manifestations of the same process.

Introduction In view of recent therapeutic breakthroughs in acute coronary syndromes (ACS) and essential demographic and socioeconomic changes in Greece, we conducted the prospective, multi-center, nationwide PHAETHON study (An Epidemiological Cohort Study of Acute Coronary Syndromes in the Greek Population) that aimed to recruit a representative cohort of ACS patients and examine current management practices and patient prognosis. Methods The PHAETHON study was conducted from May 2012 to February 2014. We enrolled 800 consecutive ACS patients from 37 hospitals with a proportional representation of all types of hospitals and geographical areas. Patients were followed for a median period of 189 days. Outcome was assessed with a composite endpoint of death, myocardial infarction, stroke, urgent revascularization and urgent hospitalization for cardiovascular causes. Results The mean age of patients was 62.7 years (78% males). The majority of patients (n=411, 51%) presented with ST-elevation myocardial infarction (STEMI), whereas 389 patients presented with NSTEMI (n=303, 38%) or UA (n=86, 11%). Overall, 58.8% of the patients had hypertension, 26.5% were diabetic, 52.5% had dyslipidemia, 71.1% had a smoking history (current or past), 25.8% had a family history of coronary artery disease (CAD) and 24.1% had a prior history of CAD. In STEMI patients, 44.5% of patients were treated with thrombolysis, 38.9% underwent a coronary angiogram (34.1% were treated with primary percutaneous coronary intervention) and 16.5% did not receive urgent treatment. The pain-to-door time was 169 minutes. During hospitalization, 301 (38%) patients presented one or more complications, and 13 died (1.6%). During follow-up, 99 (12.6%) patients experienced the composite endpoint, and 21 died (2.7%). Conclusions The PHAETHON study provided valuable insights into the epidemiology, management and outcome of ACS patients in Greece. Management of ACS resembles the management observed in other European countries. However, several issues still to be addressed by public authorities for the timely and proper management of ACS.

Background Case reports suggest that the hand-held metal detectors used for security screening generate electromagnetic fields that may interfere with pacemaker and implantable cardioverter-defibrillator (ICD) function. Objective To assess changes in function of pacemakers and ICDs after exposure to hand-held metal detectors. Design Cross-sectional study. Setting Two medical centers in Europe. Patients 388 patients (209 with pacemakers and 179 with ICDs) presenting for routine follow-up of device function between September 2009 and December 2010. Measurements Abnormalities on electrocardiography suggestive of rhythm device malfunction (pacing inhibition, loss of capture, inappropriate mode switch, ventricular oversensing, and spontaneous reprogramming) after 30 seconds of exposure to 2 widely used hand-held metal detectors with a maximal electromagnetic flux density of 6.3 µT. Results No change in device function, including pacing or sensing abnormalities or device reprogramming, was observed in any patient. Limitations The study included a convenience sample of patients, and the number of different device models tested was small. Testing was conducted in 2 clinic settings. Conclusion Hand-held metal detectors did not affect the function of pacemakers or ICDs in this sample. The use of hand-held metal detectors for security screening is probably safe for patients with pacemakers and ICDs, but these findings require confirmation. Primary funding source None.