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Open access

Agnieszka Noszczyk-Nowak, Marcin Michałek, Ewelina Kałuża, Alicja Cepiel and Urszula Pasławska

Abstract

Introduction: The prevalence of arrhythmias in dogs and the influence of sex, breed, age, and body weight were analysed over a seven-year span.

Material and Methods: In total, 1189 referrals for cardiological examination by electrocardiography were received at one academic centre in Poland between 2008 and 2014. The largest proportion of the examined dogs were cross-breeds with body weight below 25 kg (n = 153, 12.87%), followed by German Shepherds (n = 122, 10.26%), Labrador Retrievers (n = 68, 5.72%), Yorkshire Terriers (n = 63, 5.3%), and Boxers (n = 60, 5.05%). Retrospective analysis was made of 1201 standing or right recumbent electrocardiograms without pharmacological sedation. The prevalence of arrhythmias was examined in terms of sex, age, body weight, and breed of the dogs.

Results: A total of 630 (52.46%) electrocardiograms showed no signs of arrhythmia, but 96 (7.99%) and 475 (39.55%) pointed to physiological and pathological arrhythmias respectively. The most commonly diagnosed type was atrial fibrillation with 33.68% incidence, followed by ventricular arrhythmias (28%), sinus pauses (27.58%), supraventricular arrhythmias (24%), and atrioventricular blocks (22.95%). Pathological arrhythmias were most commonly found in male dogs and in German Shepherds.

Conclusions: Atrial fibrillation predominated, followed by premature ventricular complexes. Male dogs were generally more prone to heart rhythm disturbances.

Open access

Maciej Michałek, Piotr Dutkiewicz, Marcin Kiełczewski and Dariusz Pazderski

Trajectory tracking for a mobile robot with skid-slip compensation in the vector-field-orientation control system

The article is devoted to a motion control problem for a differentially driven mobile robot in the task of trajectory tracking in the presence of skid-slip effects. The kinematic control concept presented in the paper is the Vector Field Orientation (VFO) feedback approach with a nonlinear feed-forward skid-slip influence compensation scheme. The VFO control law guarantees asymptotic convergence of the position tracking error to zero in spite of the disturbing influence of skid-slip phenomena. The paper includes a control law design description, stability and convergence analysis of a closed-loop system, and practical verification of the proposed control concept. The experimental results illustrate control quality obtained on a laboratory setup equipped with vision feedback, where the Kalman filter algorithm was used in order to practically estimate skid-slip components.

Open access

Agnieszka Noszczyk-Nowak, Marcin Michałek, Adrian Janiszewski, Agnieszka Kurosad, Agnieszka Sławuta, Alicja Cepiel and Urszula Pasławska

Abstract

Introduction: Electrical cardioversion is a therapeutic procedure used to convert various types of arrhythmias back to sinus rhythm. It is used to restore the sinus rhythm in dogs with atrial fibrillation. The effect of the electrical energy used during cardioversion on red blood cells (RBC) is not fully understood. Studies on humans reported lysis of RBC following electrical cardioversion. Similar studies have not been carried out on dogs. The aim of the study was to assess the effect of electrical cardioversion on chosen RBC parameters.

Material and Methods: The study was carried out on 14 large and giant breed dogs weighing from 30 to 84 kg with lone atrial fibrillation (lone AF). Electrical cardioversion was carried out under general anaesthesia by biphasic shock with 70–360 J of energy. Blood was collected at T0 – during atrial fibrillation, prior to cardioversion, and at T1 – 30 min after electrical cardioversion. Complete blood counts as well as total and direct bilirubin concentrations were evaluated. A maximum output of 360 J was used.

Results: In all cases, electrical cardioversion was effective, and no significant changes in the number of RBC and RBC indices were noted. Similarly, there were no statistically significant differences in the levels of total and direct bilirubin.

Conclusion: Electrical cardioversion in dogs led neither to statistically nor clinically significant RBC lysis.