Efficacy of ivabradin to reduce heart rate prior to coronary CT angiography: Comparison with beta-blocker

PURPOSE: The objective of our study was to assess the effect of ivabra-dine on image quality of ECG-gated multidetector computed tomography (MDCT) coronary angiography. MATERIALS AND METHODS: Computed tomography coronary angiography (CTCA) was performed on two groups. In Group 1 (n=54), an intravenous beta-blocker was administered to patients with a heart rate >70 beats per minute (bpm) just before CTCA. In Group 2 (n=56), oral ivabradine 5 mg was administered twice a day for three days prior to CTCA examination to patients with a heart rate >70 bpm and contraindication to beta-blockers. Images acquired on two different MDCT scanners were scored in terms of image quality of the coronary artery segments using a 5-point grading scale (Grade 1, unreadable; Grade 5, excellent). RESULTS: The mean heart rates during CTCA were 64±6.7 bpm for Group 1 and 59±4.1 bpm for Group 2 (P < 0.05). Mean heart rate reduction was 9±5% and 14±8% for Groups 1 and 2, respectively (P < 0.001). A total of 880 segments were evaluated in 110 patients. When the best reconstruction interval was used, 89.8% and 95.5% of all the coronary segments showed acceptable image quality in Groups 1 and 2, respectively. Acceptable image quality of the middle right coronary artery was obtained in 78.3% of Group 1 and 92.4% of Group 2. These ratios for the other segments were 88.4% for Group 1 and 95.2% for Group 2. CONCLUSION: Reduction of heart rates with ivabradine premedication improves the image quality of CTCA. It should be considered as an alternative drug, particularly in patients with contraindications to beta-blockers. © Turkish Society of Radiology 2012

Clinical associations and prognostic value of MRI-visible perivascular spaces in patients with ischemic stroke or TIA: a pooled analysis

BACKGROUND AND OBJECTIVES: Visible perivascular spaces are an MRI marker of cerebral small vessel disease and might predict future stroke. However, results from existing studies vary. We aimed to clarify this through a large collaborative multicenter analysis. METHODS: We pooled individual patient data from a consortium of prospective cohort studies. Participants had recent ischemic stroke or transient ischemic attack (TIA), underwent baseline MRI, and were followed up for ischemic stroke and symptomatic intracranial hemorrhage (ICH). Perivascular spaces in the basal ganglia (BGPVS) and perivascular spaces in the centrum semiovale (CSOPVS) were rated locally using a validated visual scale. We investigated clinical and radiologic associations cross-sectionally using multinomial logistic regression and prospective associations with ischemic stroke and ICH using Cox regression. RESULTS: We included 7,778 participants (mean age 70.6 years; 42.7% female) from 16 studies, followed up for a median of 1.44 years. Eighty ICH and 424 ischemic strokes occurred. BGPVS were associated with increasing age, hypertension, previous ischemic stroke, previous ICH, lacunes, cerebral microbleeds, and white matter hyperintensities. CSOPVS showed consistently weaker associations. Prospectively, after adjusting for potential confounders including cerebral microbleeds, increasing BGPVS burden was independently associated with future ischemic stroke (versus 0-10 BGPVS, 11-20 BGPVS: HR 1.19, 95% CI 0.93-1.53; 21+ BGPVS: HR 1.50, 95% CI 1.10-2.06; = 0.040). Higher BGPVS burden was associated with increased ICH risk in univariable analysis, but not in adjusted analyses. CSOPVS were not significantly associated with either outcome. DISCUSSION: In patients with ischemic stroke or TIA, increasing BGPVS burden is associated with more severe cerebral small vessel disease and higher ischemic stroke risk. Neither BGPVS nor CSOPVS were independently associated with future ICH

Impact of Cerebral Microbleeds in Stroke Patients with Atrial Fibrillation

OBJECTIVES: Cerebral microbleeds are associated with the risks of ischemic stroke and intracranial hemorrhage, causing clinical dilemmas for antithrombotic treatment decisions. We aimed to evaluate the risks of intracranial hemorrhage and ischemic stroke associated with microbleeds in patients with atrial fibrillation treated with Vitamin K antagonists, direct oral anticoagulants, antiplatelets, and combination therapy (i.e. concurrent oral anticoagulant and antiplatelet) METHODS: We included patients with documented atrial fibrillation from the pooled individual patient data analysis by the Microbleeds International Collaborative Network. Risks of subsequent intracranial hemorrhage and ischemic stroke were compared between patients with and without microbleeds, stratified by antithrombotic use. RESULTS: A total of 7,839 patients were included. The presence of microbleeds was associated with an increased relative risk of intracranial hemorrhage (aHR 2.74, 95% confidence interval 1.76 - 4.26) and ischemic stroke (aHR 1.29, 95% confidence interval 1.04 - 1.59). For the entire cohort, the absolute incidence of ischemic stroke was higher than intracranial hemorrhage regardless of microbleeds burden. However, for the subgroup of patients taking combination of anticoagulant and antiplatelet therapy, the absolute risk of intracranial hemorrhage exceeded that of ischemic stroke in those with 2-4 microbleeds (25 vs 12 per 1,000 patient-years) and ≥11 microbleeds (94 vs 48 per 1,000 patient-years). INTERPRETATION: Patients with atrial fibrillation and high burden of microbleeds receiving combination therapy have a tendency of higher rate of intracranial hemorrhage than ischemic stroke, with potential for net harm. Further studies are needed to help optimize stroke preventive strategies in this high-risk group. This article is protected by copyright. All rights reserved

Thermal degradation of two different polymers bearing amide pendant groups prepared by ATRP method

Piperidinocarbonylmethyl methacrylate (PyCMMA) and 1-(piperidinocarbonyl) ethylmethacrylate (PyCEMA) monomers were synthesized. Polymerizations of PyCMMA and PyCEMA were carried out by atom transfer radical polymerization. The structure of monomers and polymers was characterized by 1 H-NMR, 13 C-NMR, and FT-IR spectroscopies. Characterization of poly(PyCMMA) and poly(PyCEMA) were carried out using differential scanning calorimetry and gel permeation chromatography. The experimental results showed that the reaction exhibited characteristics of controlled polymerization. The thermal degradation behaviors of poly(PyCEMA) and poly(PyCMMA) were studied using thermogravimetry and a single line vacuum system consisting of a degradation tube with a condenser for product collection. The poly(PyCEMA) and poly(PyCMMA) were heated from ambient temperature to 325 and 500 °C, respectively. The products of degradation were collected as a cold ring fraction (CRF). The CRFs of degradation were investigated by means of IR, 1 HNMR, and GC-MS. For the degradation of both polymers, the major products of CRFs are piperidinocarbonyl methanol and 1,2-dipiperidino,1-oxo ethane. The GC-MS, IR, and NMR data showed that depolymerization below 325 °C to the corresponding monomer was not prominantin the thermal degradation of poly(Py- CMMA). The mode of thermal degradation including formation of the major products was identified. © Akadémiai Kiadó, Budapest, Hungary 2013.Firat University Scientific Research Projects Management Unit: FUBAP-1650, FUBAP-656Acknowledgements The authors thank the Firat University Research Fund for financial support to these Projects (FUBAP-656 and FUBAP-1650)

Spectroscopic and analytic properties of new copper(II) complex of antiviral drug valacyclovir

The complexation processes between CuII and the antiviral drug, valacyclovir hydrochloride (H2L), were studied under different reaction conditions, using UV-Vis, IR and mass spectra, magnetochemical, thermogravimetric, atomic absorption, conductivity, and elemental analysis data. Using the Job method, the compositions of these complexes were determined. Under the ligand (H2L) excess (M:L =Â 1:1-1:10). In aqueous solutions, a binuclear violet complex Cu2(HL)2L(H 2O)4 is formed, with an octahedral structure. Under comparable amounts of the reagents, in MeOH solutions, a green mononuclear complex Cu(H2L)Cl2 is formed. Protonation constants of the H2L, and stability constants of its Cu2+ complexes, were determined by potentiometric titration in H2O media at 25 ± 0.02 °C under a N2 atmosphere and ionic strength of 0.1 m NaCl. It has been observed that H2L has three protonation constants. The divalent metal ion Cu2+ forms stable 2:1 and 2:2 complexes with H2L. The antimicrobial activity studies of the valacyclovir and it's complexes have been studied against some gram positive species: (Corynebacterium xerosis, Bacillus brevis, Bacillus megaterium, Bacillus cereus, Mycobacterium smegmatis, Staphylococcus aureus, Micrococcus luteus, Enterococcus faecalis) and gram negative (Pseudomonas aeruginosa, Klebsiella pneumoniae, Escherichia coli, Yersinia enterocolitica, Kluyveromyces fragilis, Saccharomyces cerevisiae, Candida albicans) bacteriaz. © Springer 2006.2004/4–6The authors gratefully acknowledge the funding of this work by the Research Fund (Project No: 2004/4–6) of Kahramanmaras¸ Sütc¸ ü İmam University, Kahraman-maras¸ , Turkey. They would like to thank Assoc. Prof. Dr. İsmet Kaya (University of 18 March, Faculty of Science and Arts, Department of Chemistry, C¸ anakk-ale, Turkey) for DTA-TG analyses

Giant myocardial bridge

Koroner arterin bir bölümünün miyokard içinde seyretmesi miyokardiyal köprü (MK) olarak adlandırılmaktadır. Diğer arterlerde de görülebilmesine rağmen MK en sık sol ön inen koroner arterde görülmektedir. MK 10-30mm uzunluğundaki kas lifleridir. Kalp kası bandı nedeniyle oluşan asıl hemodinamik bozukluk sistol sırasında oluşan darlığın, erken ve middiyastolik faza kadar devam etmesidir. Kalp kası bandı olup, hasta üçüncü grupta semptomatikse ve bu semptomlar etkin tıbbi tedaviye rağmen devam ediyor ve efor testi veya eforlu talyum sintigrafisinde iskemi tespit edilmişse suprakoroner miyotomi tercih edilmesi gereken bir yöntemdir.When a portion of the coronary arteries in the myocardium it is called myocardial bridge (MB). Although MB occurs in other arteries; it most frequently occurs over anterior descending coronary artery. MB is muscle fibers 10-30mm long. Actual hemodynamic disorder caused by myocardial band is the continuation of the narrowing that occurs during systole phase until early and middiastolic phase. If patients have myocardial band and are in the third group and symptomatic and if these symptoms continue in spite of effective medical treatment and there is ischemia in the exercise test or thallium scintigraphy with exercise test; supracoronary myotomy is a preferable method