Beta-blockers for the treatment of arrhythmias: Bisoprolol - a systematic review.

OBJECTIVES: Beta-blockers have long been successfully used for the treatment of both supraventricular and ventricular arrhythmias. However, differences exist between their chemical structure, pharmacokinetic and pharmacodynamic properties (absorption, bioavailability, metabolism, hydrophilic or lipophilic character, selective or non-selective nature, the presence or absence of intrinsic sympathomimetic activity), which may confer different antiarrhythmic properties to different beta-blockers. The aim of this study was to analyze the current existing evidence for bisoprolol for the treatment of both supraventricular and ventricular arrhythmias. MATERIAL AND METHODS: Using the keywords "bisoprolol" and "arrhythmias" or "atrial fibrillation" or "ventricular tachycardia" or "premature ventricular complexes" or "ventricular fibrillation", the Medline database was searched for articles in English or French until April 2020 assessing the role of bisoprolol in the treatment of arrhythmias. Data was then analyzed according to the type of arrhythmia treated and the quality of evidence using the GRADE approach. RESULTS: A total of 325 studies were identified, of which 28 were considered relevant to the current topic. Among these studies, 19 assessed the role of bisoprolol for the treatment of supraventricular arrhythmias, 8 its role in treating ventricular arrhythmias and 1 its role in supraventricular and ventricular arrhythmias. The quality of evidence varied from low (7 studies) to high (5 studies). CONCLUSION: Current evidence exists supporting the use of bisoprolol for the treatment of supraventricular arrhythmias, especially for rate control during atrial fibrillation. Evidence also exists for its efficacy in the treatment of ventricular arrhythmias, both in primary and in secondary prevention.

The new digit tourniquet ForgetMeNot®.

BACKGROUND: Digit tourniquets are widely used in the operating room and even more often in the emergency department to allow the exploration of injuries. A rolled surgical glove finger or silicone catheter placed at the base of the digit is a common method. However, rolled glove tourniquets are easily forgotten under the dressing and may then cause ischemia, which may require amputation. Silicone catheters are expensive single-use devices that may fail to provide effective exsanguination and must be removed by cutting, which may result in skin lesions. The ForgetMeNot® digit tourniquet (Arex, Palaiseau, France) was designed to overcome these drawbacks. The objective of this study was to assess the use of ForgetMeNot® in our clinical practice. HYPOTHESIS: The ForgetMeNot® digit tourniquet is easy to position and remove, effective, and difficult to accidentally leave in place. MATERIAL AND METHODS: ForgetMeNot® is composed of two solid cylindrical silicone strands emerging from a central crosspiece bearing two holes through which the ends of the strands can be threaded until stopped by beads on each strand. The device can be sterilised and re-used. It is easy to put in place and to remove. Threading the ends through the holes in the crosspiece forms two loops, which are passed around the tip of the finger. The device is then rolled down to the base of the digit, wrapping around itself and thus tightening gradually. At the end of the surgical procedure, pulling on the flat central crosspiece releases the device. ForgetMeNot® was tested by junior and senior surgeons in 86 patients. The following were assessed: pain, tourniquet time, effectiveness of exsanguination, complications, and the learning curve. RESULTS: Positioning the device caused no pain. No patient reported paraesthesia. Remembering to remove the device was made easy by its bright blue or yellow colour. The pressure applied ensured effective exsanguination of the digit. In no case was cutting the device required for removal. Each device was sterilised and re-used several times. DISCUSSION: The new digit tourniquet ForgetMeNot® is unlikely to be forgotten, effective, easy to use, re-usable, and associated with a low risk of skin lesions upon removal. LEVEL OF EVIDENCE: III, retrospective uncontrolled study.

The role of calcination temperature on structural and luminescence behaviour of novel apatite-based Ca2Y 8(SiO4)6O2: Ce3+,Tb3+ phosphors.

A series of novel apatite-based Ca2Y8(SiO4)6O2 phosphors doped with Ce3+ and Tb3+ were synthesized by a solid-state reaction method at different calcination temperatures and times. The comparative results of thermal analysis (TG-DTA), FTIR, X-ray diffraction (XRD) and environmental scanning electron microscope (ESEM) reveal that the firing temperature for Ca 2Y 8 (SiO4)6O2:Ce3+, Tb3+ was optimized to be 1200°C. The systematic studies on the influences of thermal treatment conditions on photoluminescence (PL) and cathodoluminescence (CL) properties were also reported. The excitation spectra of Ca2Y8(SiO4)6O2:Ce3+, Tb3+exhibited one strong excitation band at 325nm. The PL and CL results indicated that the violet-blue emission intensities about 400nm from the Ce3+ and efficient green emission at 544nm from Tb3+ were highly dependent on the calcination conditions.

Optical spectroscopy of the Ce-doped multicomponent garnets.

Here, we report our results referring to the preparation of Ce doped Y2.22MgGa2Al2SiO12, Y1.93MgAl4SiO12 and Y2.22Gd0.75Ga2Al3O12 using solid state reaction at high temperature. Several complementary methods (i.e. powder x-ray diffraction (XRPD), energy dispersive analysis of X-rays (EDX), scanning electron microscopy (SEM) and Fourier transforms infrared spectroscopy (FTIR)) were studied to examine the effects of the synthesis procedure on the morphology and structure. XRD analyses revealed that all compounds include yttrium aluminate phase with garnet structure. Cathodoluminescence (CL), radioluminescence (RL) and photoluminescence (PL) measurements were carried out for clarification of relationship between host lattice defects and the spectral luminescence emissions. Luminescence emission of phosphors is peaked at 530nm assigned to 5d-4f transitions of the dopant Ce(3+) ions with a broad emission band in 400-700nm range. Under electron irradiation, the emission spectrum of Ce doped (YGd)3Ga2Al3O12 is well defined and has a characteristic fairly narrow and sharp emission band peaking at 312nm and 624nm corresponding to transition of (6)P7/2 →(8)S7/2 and (6)GJ→(6)PJ (Gd(3+)), respectively. We suggest some of phosphors might be excellent phototherapy phosphor materials under electron excitation.

Cardiovascular profiles of scleroderma patients with arrhythmias and conduction disorders.

Introduction Arrhythmias and conduction disorders are common among patients with scleroderma. Their early identification is important, since scleroderma patients with arrhythmias have a higher mortality risk compared with scleroderma patients without arrhythmias. The aim of this study was to characterize the cardiovascular profiles of scleroderma patients with different types of arrhythmias and conduction disorders. Methods One hundred and ten consecutive patients with a diagnosis of systemic sclerosis according to the ACR criteria were included in the study. Patients underwent a 12-lead ECG and a 24-hour Holter ECG monitoring for arrhythmias and conduction disorders identification. Blood sample testing, echocardiography, spirometry, chest X-ray and, when considered appropriate, high resolution chest CT were also performed. A subgroup of 21 patients underwent NT-pro BNP level measurements. Patients' clinical and para-clinical characteristics were compared according to the presence or absence of arrhythmias and conduction disorders. Results The prevalence of arrhythmia and conduction disturbances was 60.9%. Patients with such disorders were older (54.4 ± 13.3 vs. 49.7 ± 10.1 years, p=0.05), had a higher prevalence of pulmonary hypertension (p=0.008), valve disease (p < 0.001), especially mitral and tricuspid regurgitation, chamber enlargement on echocardiography (left atrial and right ventricular, p = 0.012 and 0.005, respectively) as well as higher NT-pro BNP levels: 265.5 ± 399.7 vs. 163 ± 264.3 pg/ml, p=0.04. Conclusion Arrhythmias and conduction disorders are common in patients with scleroderma. Patients with such disorders are older, have a higher prevalence of pulmonary hypertension, more severe mitral and tricuspid regurgitation, left atrial and right ventricular dilation on echocardiography.

Rare earth activated yttrium aluminate phosphors with modulated luminescence.

Yttrium aluminate (Y3 A5 O12 ) was doped with different rare earth ions (i.e. Gd(3+) , Ce(3+) , Eu(3+) and/or Tb(3+) ) in order to obtain phosphors (YAG:RE) with general formula,Y3-x-a Gdx REa Al5 O12 (x = 0; 1.485; 2.97 and a = 0.03). The synthesis of the phosphor samples was done using the simultaneous addition of reagents technique. This study reveals new aspects regarding the influence of different activator ions on the morpho-structural and luminescent characteristics of garnet type phosphor. All YAG:RE phosphors are well crystallized powders containing a cubic-Y3 Al5 O12 phase as major component along with monoclinic-Y4 Al2 O9 and orthorhombic-YAlO3 phases as the impurity. The crystallites dimensions of YAG:RE phosphors vary between 38 nm and 88 nm, while the unit cell slowly increase as the ionic radius of the activator increases. Under UV excitation, YAG:Ce exhibits yellow emission due to electron transition in Ce(3+) from the 5d level to the ground state levels ((2) F5/2 , (2) F7/2 ). The emission intensity of Ce(3+) is enhanced in the presence of the Tb(3+) ions and is decreased in the presence of Eu(3+) ions due to some radiative or non-radiative processes that take place between activator ions. By varying the rare earth ions, the emission colour can be modulated from green to white and red. Copyright © 2015 John Wiley & Sons, Ltd.

Correlations between the surface ECG and the intracavitary electrocardiogram in typical atrial flutter.

UNLABELLED: Typical atrial flutter (cavo-tricuspid isthmus-dependent) has as an electrophysiological substrate a macro-reentry circuit localized in the right atrium. Depending on the right atrial depolarization sequence, the rotation of the macro-reentry circuit can be counterclockwise (with an inferior to superior activation of the right atrium free wall and superior to inferior activation of the interatrial septum), characterized by negative F waves in inferior leads (DII, DIII, aVF) and V6, and positive in V1 on the surface electrogram (ECG), or clockwise (with a superior to inferior activation of the right atrium free wall and inferior to superior activation of the interatrial septum) characterized by positive F waves in inferior leads (DII, DIII, aVF) and V6, and negative in V1. Nevertheless, it is considered that for the diagnosis of the typical or atypical nature of this arrhythmia, the surface ECG has limited value. The purpose of this study was to compare the relationship between the flutter rotation sequence determined by the intracavitary electrogram and the morphology of the F waves on the surface ECG. METHODS: The study included 387 patients admitted to the Cardiology - Rehabilitation Hospital from Cluj-Napoca between January 2007 and May 2010, diagnosed with typical atrial flutter during an electrophysiological study. Using the intracavitary electrograms the flutter rotation sequence was determined (clockwise or counterclockwise). The F waves' aspect on the surface ECG in leads DII, DIII, aVF, aVL, V1 and V6 was then analyzed. RESULTS: One hundred and fifty two patients (39.3%) were diagnosed with clockwise atrial flutter and 235 patients (60.7%) with counterclockwise atrial flutter. The positive predictive value (PPV) of negative F waves in inferior leads and positive in V1 was, in the case of counterclockwise atrial flutter 98%; the negative predictive value (NPV) was 79%; sensitivity (Se) was 83% and specificity (Sp) was 97%. For typical clockwise atrial flutter, the PPV of the positive F waves in the inferior leads and negative in V1 was 94% (p < 0.001); the NPV was 85%; Se was 73% and Sp was 97%. CONCLUSION: The surface ECG has a high value in determining the macroreentry circuit rotation sequence in the case of typical atrial flutter.

What is the origin of this arrhythmia?

PURPOSE: The existence of inter-atrial epicardial connections bridging the two atria at different levels has well been described and their implication in some forms of supraventricular arrhythmias is a known fact. However, up to date, little data exists in the literature showing their role in the mechanisms of focal atrial tachycardias, providing at the same time clear electroanatomical and activation maps using a three-dimensional, non-fluoroscopic mapping system. PATIENTS AND METHODS: We present the case of a 29-year-old woman with a focal atrial tachycardia with the origin in a pulmonary vein, manifested as a right atrial origin due to the conduction of the electrical impulse form the right inferior pulmonary vein (RIPV) to the postero-inferior right atrium (RA) via inter-atrial epicardial connections. Using a three-dimensional, non-fluoroscopic mapping system (CARTO, Biosense Webster), an RA activation map was created during tachycardia. RESULTS: Radiofrequency (RF) application at the earliest endocardial breakthrough site situated in the postero-inferior RA changed the right atrial depolarization sequence without terminating the arrhythmia. Subsequently, a left atrium activation map was created showing the earliest endocardial breakthrough site at the level of the RIPV ostium and RF application at this level abolished the atrial tachycardia. CONCLUSION: Inter-atrial epicardial connections can be part of the substrate of some forms of supraventricular arrhythmias. Awareness of their existence is important to the electrophysiologist, since a better understanding of transseptal activation can avoid, in some cases, unnecessary RF applications at the level of the postero-septal right atrium, with a subsequent increase in procedural risk.

Assessment of the correlation between two defining criteria for bidirectional isthmic block in the ablation of typical atrial flutter.

BACKGROUND: A complete, bidirectional conduction block in the cavotricuspid isthmus (CTI) represents the end-point of the typical atrial flutter ablation. We investigated the correlation between two criteria for successful ablation, one based on the atrial bipolar electrogram morphology before and after complete CTI conduction block, compared to the standard criteria of differential pacing and reversal in the right atrial depolarization sequence during coronary sinus (CS) pacing. METHOD: We conducted a retrospective study in 111 patients (81 males, average age 62±10 years) who underwent an atrial flutter ablation during September 2007 - July 2009 in the Cardiology - Rehabilitation Hospital, UMF Cluj-Napoca. We assessed the presence of a bidirectional block at the end of the procedure using the standard criteria. We then analyzed the morphology of the bipolar atrial electrograms adjacent to the ablation line, before and after CTI conduction block. RESULTS: A change from a qRs morphology to a rSr' morphology when pacing from the coronary sinus and from a rsr' morphology to a QRS morphology when pacing from the low-lateral right atrium was associated with a CTI conduction block. Sensitivity (Se), specificity(Sp), positive predictive value (PPV), negative predictive value (NPV) were 96%, 89%, 99% and 67% respectively. CONCLUSION: Our study suggests that the analysis of the atrial bipolar electrogram next to the ablation line before and after CTI ablation may be used as a reliable criterion to validate CTI conduction block due to its high sensitivity, specificity and positive predictive value.

The role of radiofrequency ablation as a first line therapy in the treatment of atrial flutter.

UNLABELLED: Cavo-tricuspid isthmus radiofrequency (RF) ablation is an efficient option in the treatment of atrial flutter. In the case of a well-tolerated, first episode of atrial flutter, it has a class II indication, level of evidence B, the current first-line therapeutic option being electrical cardioversion, pharmacological cardioversion or atrial overdrive pacing followed by long-term antiarrhythmic therapy. The purpose of this study was to evaluate, in a prospective manner, the recurrence rate of these two different therapeutic options after the treatment of a first episode of atrial flutter. MATERIAL AND METHODS: Between January 2007 and May 2009, for 99 patients admitted to the hospital for a first episode of atrial flutter, cardioversion was attempted either by RF ablation (group 1-42 patients), or by electrical cardioversion, pharmacological cardioversion or atrial overdrive pacing followed by long-term Amiodarone therapy (group 21-57 patients). We compared the recurrence rate of atrial flutter in the 2 groups after a follow-up period of one year. RESULTS: In group 1, sinus rhythm was achieved in all patients, with bidirectional isthmic block being obtained for 37 patients (88.1%). In group 2, conversion to sinus rhythm was obtained in all cases. The recurrence rate was 6 times higher in group 2 vs group 1 (57.9% = 33 patients vs 9.5% = 4 patients) (p = 0.01). CONCLUSION: RF ablation should be considered as a therapeutic option in the treatment of the first episode of atrial flutter, due to its significant efficiency in maintaining sinus rhythm and to its low recurrence rate.

Does syncope require rhythmic and non-rhythmic evaluation in patients with previous MI?

BACKGROUND: Multiple factors, in addition to left ventricular ejection fraction (LVEF) influence the risk of mortality in coronary artery disease. The purpose of this study was to evaluate the main causes of syncope after myocardial infarction (MI) and to propose an algorithm of management. METHODS: 356 patients consecutively admitted for syncope and history of MI (>1 month), without ventricular tachycardia (VT), underwent echocardiography, Holter monitoring, head-up tilt test, exercise testing, signal-averaged ECG, electrophysiological study (EPS) and evaluation of coronary status. The mean follow-up was 4±2 years. RESULTS: Monomorphic VT, ventricular flutter or fibrillation (VF) and supraventricular tachyarrhythmia were respectively induced at EPS in 87, 63 and 39 patients; conduction disturbances were noted in 23 patients, and 57 patients had several abnormalities. Among the 144 patients with negative EPS, coronary ischaemia was identified in 37 patients, and hypervagotonia in 27 patients. All studies remain negative in 84 patients (23.6%), more frequently women (p<0.001). Four patients died suddenly during follow-up. A longer QRS duration, a lower LVEF and grade IVa,b of Lown on Holter ECG were associated with the induction of VT. LVEF<40% and VT/VF induction were predictors of cardiac mortality, VT was a predictor of sudden death, and low LVEF and advanced age were predictors of death by heart failure. CONCLUSION: Myocardial ischaemia, hypervagotonia, conduction abnormalities, ventricular or supraventricular tachyarrhythmias were identified in 76% of patients with syncope after MI. Several factors of syncope were found in 57 patients (16%). Non-invasive rhythmological and systematic coronary status assessment should be recommended in patients with syncope following MI.

[Complete electrophysiological study remains necessary in symptomatic advanced cardiomyopathy]. / Une étude électrophysiologique complète reste nécessaire dans une cardiopathie évoluée symptomatique.

Multiple mechanisms can explain a tachycardia associated or not with a heart disease. It is important to establish its origin, particularly if advanced heart disease is present, for the treatment. Complete electrophysiological study remains an important means of diagnosis. We report the case of a 39-year old man, who had a dilated cardiomyopathy since the age of 25 years and who complained of tachycardia. These symptoms were shown to be related to atrioventricular nodal re-entrant tachycardia at electrophysiological study and a specific treatment was indicated.

Automated multiple development thin layer chromatography of some plant extracts.

The separation of ten plant extracts using automated multiple development thin-layer chromatography (AMD -TLC) is described. Alcoholic extracts were obtained from Cinchona succirubra, Aesculus hippocastanum, Berberis vulgaris. Artemisia abrotanum, Carduus marianus, Thuja occidentalis, Baptisia tinctoria, Paulinia cupana, Lycopus europaeus and Echinacea angustifolia. The separation was performed on silica plates (Sil G-50 UV 254 (Macherey-Nagel), 10 x 20 cm). AMD was achieved in 25 steps using methanol, ethyl acetate, toluene, 1,2-dichloroethane, 25% ammonia solution and anhydrous formic acid as modifiers. The chromatograms were evaluated with a Shimadzu CS-9000 dual-wavelength flying-spot scanner. Better separations were obtained using AMD than isocratic elution.

The action of glucagon on gastric acid secretion and serum pepsinogen I.

In 39 patients the following were assessed: gastric acid secretion (mmol/hour), gastric juice volume (ml/hour), glycemia (mg%), and in 10 of them also pepsinogen I serum concentration (ng/ml). All these parameters were determined in basal conditions and after administration of glucagon. Glucagon induced achlorhydria in 33.3% of the patients, hypochlorhydria in 33.3%, did not influence HCl in 12.8%, and hyperchlorhydria in 20.5%. The gastric juice volume changed in parallel with chlorhydria. The HCl secretion did not correlate with the glycemia levels. Pepsinogen I was not significantly influenced by glucagon. It may be concluded that glucagon had a two-fold action on HCl secretion: (a) in two thirds of the patients studied it induced hypo- or achlorhydria; (b) in about 20% it induced hyperchlorhydria.

[The recovery of work capacity within the framework of short-term antitubercular chemotherapy]. / Recuperarea capacitatii de munca în cadrul chimioterapiei antituberculoase de scurta durata.

The authors compare the results of chemotherapy reflected in the proportion of recoveries of work capacity and the number of retired persons in two groups of patients--one including 102 cases treated between 1970 and 1971 by a 3/6 regimen, and another one including 91 patients treated in 1986 by a modern intensive 3 + 3 regimen. The data indicate better results with the 1986 lot as compared with the 1970-1971 lot. In the 1986 group there were no fatalities and the persons that recovered their work capacity represented 90.1% of the total. By contrast, in the group treated between 1970 and 1971 there were two fatalities and only 84.3% of all the patients did recover the work capacity. The number of retired persons decrease from 11.7% in the first group to 7.7% in the second. Temporary incapacity decreased from an average of 321 days to an average of 267 days in the second group. All these results were obtained by shortening the treatment from an average of 9 months to an average of 6 months.

Structural and catalytic properties of L-alanine dehydrogenase from Bacillus cereus.

Alanine dehydrogenase from Bacillus cereus, a non-allosteric enzyme composed of six identical subunits, was purified to homogeneity by chromatography on blue-Sepharose and Sepharose 6B-CL. Like other pyridine-linked dehydrogenases, alanine dehydrogenase is inhibited by Cibacron blue, competitively with respect to NADH and noncompetitively with respect to pyruvate. The enzyme was inactivated by 0.1 M glycine/HCl (pH 2) and reactivated by 0.1 M phosphate (pH 8) supplemented with NAD+ or NADH. The reactivation was characterized by sigmoidal kinetics indicating a complex mechanism involving rate-limiting folding and association steps. Cibacron blue interfered with renaturation, presumably by competition with NADH. Chromatography on Sepharose 6B-CL of the partially renatured alanine dehydrogenase led to the separation of several intermediates, but only the hexamer was characterized by enzymatic activity. By immobilization on Sepharose 4B, alanine dehydrogenase from B. cereus retained 66% of the specific activity of the soluble enzyme. After denaturation of immobilized alanine dehydrogenase with 7 M urea, 37% of the initial protein was still bound to Sepharose, indicating that on the average the hexamer was attached to the matrix via, at most, two subunits. The ability of the denatured, immobilized subunits to pick up subunits from solution shows their capacity to fold back to the native conformation after urea treatment. The formation of "hybrids" between subunits of enzyme from B. cereus and Bacillus subtilis demonstrates the close resemblance of the tertiary and quaternary structures of alanine dehydrogenases from these species.

Integrated stereotaxic imaging with CT, MR imaging, and digital subtraction angiography.

A stereotaxic frame, compatible with digital subtraction angiography, computed tomography, and magnetic resonance imaging, is described along with a set of software programs that run in an independent imaging computer system, as well as in the computers associated with each modality. Plexiglas plates fastened to the sides of the frame contain fiducial markers that can be recognized in the images and from which the section position and in-plane coordinates of any point in the image relative to the frame may be determined. Coordinate measurements of isolated point targets may be made to an accuracy of better than +/- 1 mm within a 15-cm field of view in the plane of the section or projection on all modalities. The stereotaxic system is of sufficiently high accuracy to be used on a routine clinical basis with one or more of the above modalities.

Catalytic properties of Sepharose-bound L-alanine dehydrogenase from Bacillus cereus.

(1) L-Alanine dehydrogenase from Bacillus cereus was purified by a two-step chromatographic procedure involving Cibacron-Blue 3G-A Sepharose 4B-CL, and Sepharose 6B-CL, and immobilized on CNBr-activated Sepharose 4B. (2) Following immobilization via two of the six subunits, L-alanine dehydrogenase retained 66% of the specific activity of the soluble enzyme. The affinity of the immobilized enzyme for NH4+, pyruvate and L-alanine, was not different to that of the soluble form. The Km of the Sepharose-bound L-alanine dehydrogenase for pyridine coenzymes was 6-8-times higher than in the soluble case. (3) The stability of L-alanine dehydrogenase towards urea or thermal denaturation was increased by immobilization. (4) The incubation at 37 degrees C for 24 h of the immobilized L-alanine dehydrogenase with 3 M NH4Cl/NH4OH buffer (pH 9) released 70% of the enzyme. The specific activity and the affinity of the 'solubilized' L-alanine dehydrogenase for the pyridine coenzymes was the same as that obtained with the original, soluble L-alanine dehydrogenase.