1,721,003 research outputs found
Implantable cardioverter defibrillator system with floating atrial sensing dipole: A single-center experience
No full textBackground The concept of a single-lead dual-chamber implantable cardioverter defibrillator (ICD) with floating sensing atrial dipole has been proven safe and functional. We report a single-center experience with this ICD system; the major focus of the work is on the recorded atrial activation and its stability on a medium term follow-up.Methods Thirteen patients received a DX ICD (BIOTRONIK SE & Co, Berlin, Germany) with the Linox Smart S DXProMRI ICD lead; the implantation data were reported. Daily P- and R-wave sensing amplitude was collected and followed up during 200 days; their coefficient of variance (CV) was calculated. In addition, all the atrial and ventricular high-rate episodes were analyzed.Results The total x-ray exposure time was 3.9 ± 1.8 minutes. The overall mean sensing was 4.2 ± 1.9 mV for P wave and 12.9 ± 4.5 mV for R wave. The CV was significantly higher for the P-wave amplitude than for the R-wave one (0.25 ± 0.11 vs 0.08 ± 0.06; P < 0.001). A total of 27 high ventricular rate episodes were recorded and correctly discriminated by the device. Fifty-six high atrial rate episodes were recorded, 49 were true arrhythmic events.Conclusions The single-lead ICD system with floating atrial dipole provides reliable atrial sensing amplitude over time. The physician, without the implantation of an additional lead, has the atrial information that may be used for the discrimination of supraventricular tachyarrhythmia/ventricular tachycardia, for the early detection of atrial fibrillation episodes and for the evaluation of changes in the patient's heart status
Ablation of typical atrial flutter: a prospective study of cooled-tip versus 8-mm-tip catheters
No full textAim: Both ablation catheters with irrigated system and 8mm tip-catheters have shown to be more effective for typical atrial flutter radiofrequency (RF) ablation when compared to conventional 4 mm tip catheter. The purpose of this prospective study was to compare the efficiency of radiofrequency catheter ablation (RFA) of the cavotricuspid isthmus using a new type of open irrigation-tip catheter versus 8 mm tip-catheters to eliminate atrial flutter (AFL).
Methods: Sixty consecutive patients, matched for age, presence of cardiopathy, atrial dimensions and comorbidity, underwent RF ablation of cavotricuspid isthmus (CTI) for the treatment of typical atrial flutter, using an open irrigated tip catheter - Surround FlowTM - (N.=30) or an 8-mm-tip catheter (N.=30). The RF pulses were applied point-by-point for 30 seconds, with power limited at 35 w for the irrigated catheter and by temperature control (60/70 w) for the 8-mm catheter.
Results: The CTI block was successfully performed in 100% of cases. There was no significant difference with regard to ablation parameters, such as total time of RF ablation (608±324 vs. 556±244 s, P=0.79), number of RF applications (12±8 vs. 10±5, P=0.56), total procedure duration (86.4±23.6 vs. 78.1±22.5 min, P=0.58) and time of fluoroscopy (12±6 vs. 14±6 min, P=0.25) and periprocedural complications (1 groin hematoma in the 8 mm group). During follow-up of 11.6 months on average, one patient in the 8 mm group had recurrence of typical atrial flutter.
Conclusion: Efficacy and safety of CTI ablation was comparable between both techniques (open irrigated catheter and 8mm tip catheter). The ablation parameters were comparable and homogeneous between the two groups
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Full text link“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
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