Convergent double coronary sinus potentials during atrial tachycardia

The analysis of the patterns and timing of coronary sinus activation provides a rapid stratification of the most likely macro-re-entrant atrial tachycardias and points toward the likely origin of centrifugal ones by comparing the left atrial and coronary sinus activation sequence and morphology during sinus rhythm and atrial tachycardia. The analysis of both the near- and far-field electrogram morphology of atrial signals also gives important clues in determining the mechanism of the arrhythmia

The roles of pre–P-wave versus peri–P-wave fractionated electrograms for atrial substrate beyond entrainment response

Atrial tachycardia (AT) with alternating cycle lengths is sparsely reported, and, hence, the ideal mapping strategy has not been firmly established. Beyond the entrainment during tachycardia, some fragmentation characteristics might also give important clues for its possible participation in the macro–re-entrant circuit. We discuss a patient with prior atrial septal defect surgical closures who presented with dual macro–re-entrant ATs related to a fragmented area on the right atrial free wall (240 ms) and the cavotricuspid isthmus (260 ms), respectively. After ablation of the fastest AT on the lateral right atrial free wall, the cycle of the first AT changed to the second AT that was interrupted on cavotricuspid isthmus, proving the dual tachycardia mechanism. This case report addresses the utilization of electroanatomic mapping information as well as fractionated electrogram timing with respect to the surface P-wave as guides for ablation location

Paradoxical para-hisian pacing response

Para-Hisian pacing (PHP) is among the most useful maneuvers in cardiac electrophysiology during sinus rhythm and identifies whether retrograde conduction is dependent on the atrioventricular (AV) node. In this maneuver, the retrograde activation time and pattern are compared during capture and loss of capture of the His bundle while pacing from a paraHisian position. A common misconception about PHP is that it is useful only for septal accessory pathways (APs). However, even with left or right lateral pathways, as long as pacing from the para-Hisian region conducts to the atrium with the activation sequence being analyzed, it can be used to determine whether that activation is AV node–dependent or AP-dependent

Helicobacter pylori infection according to ABO blood group among blood donors in Kosovo

Introduction: Numerous studies have reported a high prevalence of Helicobacter pylori infection among healthy and non-healthy persons in different places. The Aim of the study is to investigate the seroprevalence of H. pylori infection among Kosovo’s Blood donor associated with ABO/Rhesus blood group. Methods: 671 blood donors are tested for H. pylori antibodies and results are classifi ed by way of donation, age, gender, blood groups and education level. Serum antibodies are analyzed by Enzyme Linked Fluorescent Assay test for H. pylori IgG with Biomerieux HPY-VIDAS. Results: The frequency of IgG antibody for H. pylori among healthy blood donors is 56.9%, there is not found any difference between voluntary and non-voluntary blood donors (57.4% respectively 56.3%)(OR=1.05; 95% CI 0.76 to 1.43; p=0.8). H pylori IgG antibodies positive are detected in 57.0 % ( 126 of 221) of women, compared with 56.9 % ( 256 of 450) of men(OR=0.99; 95% CI 0.72 to 1.38; p=0.96). Serpositive donors are older than seronegative ones (31.9 years, respectively 29.5 years, p=0.02). Mean value of IgG antibody of H. pylori is 3.61 with no significant difference between males and females (3.72 respectively 3.44; p=0.2). The seroprevalence of H. pylori infection is similar among blood groups: O (57.4%), A (56.2%), B (59.6%), AB (51.4%), RhD positive (56.7%) and RhD negative (58.3%). Conclusions: The seropositivity of H. pylori is moderately higher in the non voluntary and familiar blood donors among the total Kosovo blood donors. There is not found a significant relationship between infection with H. pylori and ABO/Rhesus blood group among blood donors

Dose-volume histogram constrains for small intestine in postoperative transcutaneous radiotherapy of endometrial carcinoma: comparison between conventional and conformal techniques

<strong>Introduction:</strong> The aim of this study was to determine the dose-volume histogram (DVH) constrains of conventional and conformal transcutaneous radiotherapy for small intestine and perform their comparison.<br /><strong>Methods</strong>: This retrospective-prospective study included patients who were treated for endometrial cancer using conventional transcutaneous radiotherapy at the Department of Radiotherapy Clinic of Oncology,<br />Hematology and Radiotherapy, University Clinical Center Tuzla in the period from 2009 to 2011. The study was performed on patients of all ages suffering from this condition. The study involved 35 patients. DVH<br />parameters which were analyzed are: minimum dose (Dmin), maximum dose (Dmax), medium dose (Daver) of the small intestine, as well as the volume of the small intestine, which is included in 75%, 95% and 100%<br />dose (V33,75Gy, V42,75Gy, V45Gy) expressed in percentages and cubic centimeters of the affected organ. Working hypothesis was tested with paired t test. The difference between the variables at the level of p <0.05 was considered statistically significant.<br /><strong>Results: </strong>DVH constrains of transcutaneous conformal radiotherapy showed signifi cantly smaller dose contribution on small intestine than DVH parameters of conventional transcutaneous radiotherapy (p<0.0001).<br /><strong>Conclusion:</strong> The dose contribution on small intestine was signifi cantly lower by planning three-dimensional conformal transcutaneous radiotherapy in comparison to the conventional planning

CT angiography and Color Doppler ultrasonography features and sensitivity in detection of carotid arteries diseases

<p><strong>Introduction: </strong>The aim of this research was to compare specifi city and sensitivity of Color Doppler ultrasonography<br />with CT angiography.</p><p><strong>Methods:</strong> A total of one hundred patients suffering from carotid artery disease (n=200) were tested in this research in the period from June till October, 2011. Average age of the patients was 61.5 years, and most of the patients were in the age group ranging from 55 to 65 years. The level of carotid artery stenosis is measured according to Standards of the North America Symptomatic Carotid Endarterectomy Trail study,by method of Color Doppler ultrasonography and CT angiography.</p><p><strong>Results: </strong>Stenosis <50% registered by Doppler ultrasonography was found in 62% and by CT angiography in 64% patients. Stenosis from 70 to 79% registered by Doppler ultrasonography was found in 88% and by CT angiography in 82% patients. In patients with level of stenosis 70-79% there was a tendency<br />of registering the stenosis to be higher by Color Doppler ultrasonography, than by CT angiography. In the case of the occlusion, there was also the similar observation, with variation of 8% carotid arteries.</p><p><strong>Conclusion: </strong>Extracranial Doppler and color duplex ultrasound enable reliable detection of both stenosis and occlusion of carotid arteries and accordingly they occupy an important place in radiological algorithm. When it comes to CT angiography it can be concluded that it can provide accurate and exact information regarding the condition of blood vessels as good as Digital Subtractive Angiography can.</p

High-throughput fabrication of vascularized spheroids for bioprinting

Overcoming the problem of vascularization remains the main challenge in the field of tissue engineering. As three-dimensional (3D) bioprinting is the rising technique for the fabrication of large tissue constructs, small prevascularized building blocks were generated that can be incorporated throughout a printed construct, answering the need for a microvasculature within the small micron range (<10 mu m). Uniform spheroids with an ideal geometry and diameter for bioprinting were formed, using a high-throughput non-adhesive agarose microwell system. Since monoculture spheroids of endothelial cells were unable to remain stable, coculture spheroids combining endothelial cells with fibroblasts and/or adipose tissue derived mesenchymal stem cells (ADSC) as supporting cells, were created. When applying the favorable coculture ratio, viable spheroids were obtained and endothelial cells spontaneously formed a capillary-like network and lumina, as shown by immunohistochemistry and transmission electron microscopy. Especially the presence of ADSC led to a higher vascularization and extracellular matrix production of the microtissue. Moreover, spheroids were able to assemble at random in suspension and in a hydrogel, creating a macrotissue. During at random assembly, cells reorganized, creating a branched capillary-network throughout the entire fused construct by inoculating with capillaries of adjacent spheroids. Combining the advantage of this natural capacity of microtissues to self-assemble and the controlled organization by bioprinting technologies, these prevascularized spheroids can be useful as building blocks for the engineering of large vascularized 3D tissues

Generation and bioprinting of prevascularized spheroids using a photo-crosslinkable gelatin

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Atrial tachycardia with cycle length alternans

Tachycardia-induced tachycardia, or so-called double tachycardia, appears to be a relatively rare condition. The underlying mechanism for stable beat-to-beat cycle length variability (alternans) in atrial tachycardia has been sparsely reported