Accurate and reproducible reconstruction of coronary arteries and endothelial shear stress calculation using 3D OCT: Comparative study to 3D IVUS and 3D QCA

Background: Geometrically-correct 3D OCT is a new imaging modality with the potential to investigate the association of local hemodynamic microenvironment with OCT-derived high-risk features. We aimed to describe the methodology of 3D OCT and investigate the accuracy, inter- and intra-observer agreement of 3D OCT in reconstructing coronary arteries and calculating ESS, using 3D IVUS and 3D QCA as references. Methods-Results: 35 coronary artery segments derived from 30 patients were reconstructed in 3D space using 3D OCT. 3D OCT was validated against 3D IVUS and 3D QCA. The agreement in artery reconstruction among 3D OCT, 3D IVUS and 3D QCA was assessed in 3-mm-long subsegments using lumen morphometry and ESS parameters. The inter- and intra-observer agreement of 3D OCT, 3D IVUS and 3D QCA were assessed in a representative sample of 61 subsegments (n ¼ 5 arteries). The data processing times for each reconstruction methodology were also calculated. There was a very high agreement between 3D OCT vs. 3D IVUS and 3D OCT vs. 3D QCA in terms of total reconstructed artery length and volume, as well as in terms of segmental morphometric and ESS metrics with mean differences close to zero and narrow limits of agreement (BlandeAltman analysis). 3D OCT exhibited excellent inter- and intra-observer agreement. The analysis time with 3D OCT was significantly lower compared to 3D IVUS. Conclusions: Geometrically-correct 3D OCT is a feasible, accurate and reproducible 3D reconstruction technique that can perform reliable ESS calculations in coronary arteries

Riociguat treatment in patients with chronic thromboembolic pulmonary hypertension: Final safety data from the EXPERT registry

Objective: The soluble guanylate cyclase stimulator riociguat is approved for the treatment of adult patients with pulmonary arterial hypertension (PAH) and inoperable or persistent/recurrent chronic thromboembolic pulmonary hypertension (CTEPH) following Phase

Omecamtiv mecarbil in chronic heart failure with reduced ejection fraction, GALACTIC‐HF: baseline characteristics and comparison with contemporary clinical trials

Aims: The safety and efficacy of the novel selective cardiac myosin activator, omecamtiv mecarbil, in patients with heart failure with reduced ejection fraction (HFrEF) is tested in the Global Approach to Lowering Adverse Cardiac outcomes Through Improving Contractility in Heart Failure (GALACTIC‐HF) trial. Here we describe the baseline characteristics of participants in GALACTIC‐HF and how these compare with other contemporary trials. Methods and Results: Adults with established HFrEF, New York Heart Association functional class (NYHA) ≥ II, EF ≤35%, elevated natriuretic peptides and either current hospitalization for HF or history of hospitalization/ emergency department visit for HF within a year were randomized to either placebo or omecamtiv mecarbil (pharmacokinetic‐guided dosing: 25, 37.5 or 50 mg bid). 8256 patients [male (79%), non‐white (22%), mean age 65 years] were enrolled with a mean EF 27%, ischemic etiology in 54%, NYHA II 53% and III/IV 47%, and median NT‐proBNP 1971 pg/mL. HF therapies at baseline were among the most effectively employed in contemporary HF trials. GALACTIC‐HF randomized patients representative of recent HF registries and trials with substantial numbers of patients also having characteristics understudied in previous trials including more from North America (n = 1386), enrolled as inpatients (n = 2084), systolic blood pressure < 100 mmHg (n = 1127), estimated glomerular filtration rate < 30 mL/min/1.73 m2 (n = 528), and treated with sacubitril‐valsartan at baseline (n = 1594). Conclusions: GALACTIC‐HF enrolled a well‐treated, high‐risk population from both inpatient and outpatient settings, which will provide a definitive evaluation of the efficacy and safety of this novel therapy, as well as informing its potential future implementation

The differential evolution method in single and multi objective aerodynamic optimization using parallel processing

120 σ.Η διπλωματική αυτή εργασία επικεντρώνεται στον αλγόριθμο Διαφορικής Εξέλιξης (ΔΕ), μία πληθυσμιακή στοχαστική μέθοδο βελτιστοποίησης. Η εργασία ξεκινά με τη βιβλιογραφική επισκόπηση των αλγορίθμων ΔΕ και συνεχίζεται με τον προγραμματισμό σε γλώσσα Fortran77 του σχετικού λογισμικού. Η μέθοδος, στη μορφή στην οποία κατέληξε η παρούσα εργασία, έχει αρκετά πρόσθετα στοιχεία συγκριτικά με τους “κλασικούς” αλγόριθμους ΔΕ, επεικτείνεται σε προβλήματα πολυκριτηριακής βελτιστοποίησης και χρησιμοποιεί πολυεπεξεργασία. Οι νέες ουσιαστικές παρεμβάσεις που έγιναν βασίζονται ουσιαστικά σε μετεμφυτεύσεις στοιχείων του γενικευμένού Εξελικτικού Αλγορίθμου (περιοχή στην οποία το Εργαστήριο Θερμικών Στροβιλομηχανών του Ε.Μ.Π. έχει πολυετή εμπειρία). Με τις νέες τροποποιήσεις η μέθοδος έγινε ακόμα πιο γρήγορη και σταθερή στη συμπεριφορά της. Στα νέα στοιχεία της μεθόδου συγκαταλέγεται μία καινούργια τεχνική αποδοχής των απογόνων και ανανέωσης του πληθυσμού σε προβλήματα πολλών στόχων. Ο κώδικας προγραμματίστηκε για να δουλεύει και σε πολυεπεξεργαστικό περιβάλλον, κάνοντας χρήση των βιβλιοθηκών του PVM και της λογικής συντονιστή-εργάτη ώστε να επιτευχθεί ταυτόχρονη αξιολόγηση μελών του πληθυσμού από τους διαθέσιμους επεξεργαστές. Ο κώδικας πιστοποιήθηκε επιτυχώς σε μαθηματικά προβλήματα ενός και περισσοτέρων στόχων και εφαρμόστηκε με επιτυχία σε πραγματικά προβλήματα αεροδυναμικής σχεδίασης στις στροβιλομηχανές.This diploma thesis centers upon the Differential Evolution Algorithm (DE), which is a stochastic population based optimization method. We start with a conspectus of the algorithms found to the bibliography and we programmed in Fortran77 the corresponding software. The final product of the above effort was generalized for use in multi objective optimization problems, uses parallel processing and many additional characteristics that do not exist in the theory of the classical DE algorithms have been introduced. These new additions were based on implants from the generalized Evolution Algorithm (an area in which the lab of Thermal Turbomachines is highly experienced). With the use of these alterations, the method becomes faster and more robust. Among the various characteristics implanted, it is also proposed a new technique for the acceptance of the offspring in multi objective problems. The software was programmed in order to to operate also by using parallel processing, by making use of the P.V.M. libraries and the master-slave logic, evaluating by that way the cost function of many members of the population in the same time using all the available processors. The software was tested successfully on mathematical problems of single and multi objective optimization problems and was implemented on real aerodynamic design problems in turbomachines.Δημήτριος Χ. Καρβούνη

The differential evolution method in single and multi objective aerodynamic optimization using parallel processing

120 σ.Η διπλωματική αυτή εργασία επικεντρώνεται στον αλγόριθμο Διαφορικής Εξέλιξης (ΔΕ), μία πληθυσμιακή στοχαστική μέθοδο βελτιστοποίησης. Η εργασία ξεκινά με τη βιβλιογραφική επισκόπηση των αλγορίθμων ΔΕ και συνεχίζεται με τον προγραμματισμό σε γλώσσα Fortran77 του σχετικού λογισμικού. Η μέθοδος, στη μορφή στην οποία κατέληξε η παρούσα εργασία, έχει αρκετά πρόσθετα στοιχεία συγκριτικά με τους “κλασικούς” αλγόριθμους ΔΕ, επεικτείνεται σε προβλήματα πολυκριτηριακής βελτιστοποίησης και χρησιμοποιεί πολυεπεξεργασία. Οι νέες ουσιαστικές παρεμβάσεις που έγιναν βασίζονται ουσιαστικά σε μετεμφυτεύσεις στοιχείων του γενικευμένού Εξελικτικού Αλγορίθμου (περιοχή στην οποία το Εργαστήριο Θερμικών Στροβιλομηχανών του Ε.Μ.Π. έχει πολυετή εμπειρία). Με τις νέες τροποποιήσεις η μέθοδος έγινε ακόμα πιο γρήγορη και σταθερή στη συμπεριφορά της. Στα νέα στοιχεία της μεθόδου συγκαταλέγεται μία καινούργια τεχνική αποδοχής των απογόνων και ανανέωσης του πληθυσμού σε προβλήματα πολλών στόχων. Ο κώδικας προγραμματίστηκε για να δουλεύει και σε πολυεπεξεργαστικό περιβάλλον, κάνοντας χρήση των βιβλιοθηκών του PVM και της λογικής συντονιστή-εργάτη ώστε να επιτευχθεί ταυτόχρονη αξιολόγηση μελών του πληθυσμού από τους διαθέσιμους επεξεργαστές. Ο κώδικας πιστοποιήθηκε επιτυχώς σε μαθηματικά προβλήματα ενός και περισσοτέρων στόχων και εφαρμόστηκε με επιτυχία σε πραγματικά προβλήματα αεροδυναμικής σχεδίασης στις στροβιλομηχανές.This diploma thesis centers upon the Differential Evolution Algorithm (DE), which is a stochastic population based optimization method. We start with a conspectus of the algorithms found to the bibliography and we programmed in Fortran77 the corresponding software. The final product of the above effort was generalized for use in multi objective optimization problems, uses parallel processing and many additional characteristics that do not exist in the theory of the classical DE algorithms have been introduced. These new additions were based on implants from the generalized Evolution Algorithm (an area in which the lab of Thermal Turbomachines is highly experienced). With the use of these alterations, the method becomes faster and more robust. Among the various characteristics implanted, it is also proposed a new technique for the acceptance of the offspring in multi objective problems. The software was programmed in order to to operate also by using parallel processing, by making use of the P.V.M. libraries and the master-slave logic, evaluating by that way the cost function of many members of the population in the same time using all the available processors. The software was tested successfully on mathematical problems of single and multi objective optimization problems and was implemented on real aerodynamic design problems in turbomachines.Δημήτριος Χ. Καρβούνη

Efficacy and safety of high dose versus low dose furosemide with or without dopamine infusion: The Dopamine in Acute Decompensated Heart Failure II (DAD-HF II) Trial

Aims: The role of low-dose dopamine infusion in patients with acute decompensated heart failure (ADHF) remains controversial. We aim to evaluate the efficacy and safety of high-versus low-dose furosemide with or without low-dose dopamine infusion in this patient population. Methods and results: 161 ADHF patients (78 years; 46% female; ejection fraction 31%) were randomized to 8-hour continuous infusions of: a) high-dose furosemide (HDF, n = 50, 20 mg/h), b) low-dose furosemide and low-dose dopamine (LDFD, n = 56, 5 mg/h and 5 mu g kg(-1) min(-1) respectively), or c) low-dose furosemide (LDF, n = 55, furosemide 5 mg/h). The main outcomes were 60-day and one-year all-cause mortality (ACM) and hospitalization for HF (HHF). Dyspnea relief (Borg index), worsening renal function (WRF, rise in serum creatinine (sCr) >= 0.3 mg/dL), and length of stay (LOS) were also assessed. The urinary output at 2, 4, 6, 8, and 24 h was not significantly different in the three groups. Neither the ACM at day 60 (4.0%, 7.1%, and 7.2%; P = 0.74) or at one year (38.1%, 33.9% and 32.7%, P = 0.84) nor the HHF at day 60 (22.0%, 21.4%, and 14.5%, P = 0.55) or one year (60.0%, 50.0%, and 47%, P = 0.40) differed between HDF, LDFD, and LDF groups, respectively. No differences in the Borg index or LOS were noted. WRF was higher in the HDF than in LDFD and LDF groups at day 1 (24% vs. 11% vs. 7%, P < 0.0001) but not at sCr peak (44% vs. 38% vs. 29%, P = 0.27). No significant differences in adverse events were noted. Conclusions: In ADHF patients, there were no significant differences in the in-hospital and post-discharge outcomes between high-vs. low-dose furosemide infusion; the addition of low-dose dopamine infusion was not associated with any beneficial effects. (C) 2014 Elsevier Ireland Ltd. All rights reserved