The aim of this study was to demonstrate the diagnostic accuracy of P-wave dispersion in predicting recurrence of atrial fibrillation in dogs with sinus rhythm restoration after external cardioversion. The study was performed on 15 dogs, which underwent electrical external cardioversion after atrial fibrillation. Nine-lead surface electrocardiogram of each dog was recorded 1 min after the cardioversion process to measure the P-wave duration. Dogs with recurrent atrial fibrillation had significantly higher P-wave dispersion compared to dogs that had a sinus rhythm lasting more than 3 months (9.26 ±2.01 ms vs 20.9 ±2.18 ms, P=0.001). This study suggests that P-wave dispersion analysis in dogs after a successful external electrical cardioversion has diagnostic accuracy to predict the recurrence of atrial fibrillation.
The study presents a comparison of the results received from dogs with dilated cardiomyopathy (DCM) that died during the first 30 d of observation and from dogs with DCM that survived the first 30 d after the ECG. No differences were noted in the duration of QT or QTc in healthy dogs and dogs with DCM. QTcd was significantly higher in dogs with DCM and in dogs with DCM, which did not survive over 30 d of observation and dogs with DCM that died after the 30th d of observation. The presence of T-wave alternans (TWA) was more frequently observed in dogs with DCM (85% of the dogs) that died in less than 30 d during the observation. QTcd and TWA seem to be a useful non-invasive diagnostic tool to anticipate the risk of cardiac death in dogs with DCM.
Results of supravital and post-mortem observation of embolic-thrombotic complications in dogs, in the course of endotoxaemia induced by pyometra and phlegmonous pneumonia due to infection with Pseudomons aeruginosa, or endomyocarditis caused by Staphylococcus aureus infection were described. Multiorgan embolic-thrombotic complications were diagnosed in all presented cases. Most probably, the complications developed due to thrombocytopoenia secondary to platelet activation and exacerbation of endotoxin-induced DIC syndrome. In all the dogs, a disturbed cardiac rhythm was diagnosed supravitally. The rhythm disturbances might reflect myocardial injury due to presence of bacterial endotoxins in blood. The myocardial injury was confirmed by histopathological examination.
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.
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.
Electrical cardioversion in dogs led neither to statistically nor clinically significant RBC lysis.
The study was an attempt to determine the possibilities of using ovocystatin, a component of a new generation product of natural origin, in local therapy of atopic dermatitis in dogs by suppressing pruritus during illness. Chicken egg cystatin was used locally in the interdigital spaces of forelimbs of dogs used in the experiment. The degree of pruritus and clinical changes in the animals were defined using CADESI-03 scale before and after the beginning of the experiment. The results obtained proved that ovocystatin may be used as a substance suppressing pruritus in atopic dermatitis.
Although peripheral blood analysis has become increasingly automated, microscopy is the only available method for the diagnosis of anisocytosis and poikilocytosis. The aims of the study were to compare RBC volume data obtained with two different analysers and by manual assessment of smears and to compare this data between dogs in various stages of heart failure secondary to degenerative mitral valvular (DMV) disease. The impact of diuretic administration on RBC morphology was also assessed.
Material and Methods
Sixty-eight dogs, 56 in different stages of DMV disease and 12 as healthy controls, were studied. Impedance and flow cytometry haematological analyses were performed for each animal. Additionally, two smears were prepared for manual analysis. RBC structure, staining, and size differences were recorded.
There were no significant differences between the blood morphological parameters assessed using haematological analysers nor between dogs receiving diuretic treatment and those not treated. Based on the manual smear, significantly higher erythrocyte anisocytosis was observed in the dogs with symptomatic DMV disease than in the control group.
Haematological analysers based on impedance and flow cytometry provide reliable and comparable morphological results in dogs with heart failure. However, microscopic assessment of blood smears is a more reliable tool to detect erythrocyte anisocytosis.
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.
In recent years, the high sensitivity and specificity of novel miRNA biomarkers have been utilised for early diagnosis and treatment monitoring of various diseases. Previous reports showed that abnormal expression of miR-208 in mice resulted in the development of an aberrant cardiac conduction system and consecutive arrhythmias. On the other hand, a study on infarcted human heart tissue showed upregulation of miR-208a in subjects with ventricular tachyarrhythmias compared to healthy controls. We prospectively investigated the expression of miR-208a and -208b in the serum of dogs presenting different cardiac arrhythmias.
Material and Methods
A total of 28 dogs with atrial fibrillation (n = 8), ventricular premature contractions (n=6), conduction system disturbances (n = 7), and free of heart conditions (as controls) (n = 7) were enrolled in the study. Total RNA was extracted from serum samples and miR-208a and -b, miR-16 as well as a cel-miR-39-5p spike-in were analysed with qPCR and ddPCR.
miR-208a and miR-208b were not expressed in any of the samples. The calculated ddPCR miR-16 relative expression (normalised with cel-miR-39 spike-in) showed a good correlation (r = 0.82; P < 0.001) with the qPCR results.
This outcome warrants further investigation, possibly focusing on tissue expression of miR-208 in the canine heart.
Atrial fibrillation may potentially contribute to oxidative stress to a greater extent than chronic heart failure. The aim of the study was to compare the serum total antioxidant capacity and enzymatic antioxidant defence of dogs with chronic heart failure and atrial fibrillation with those of subjects with chronic heart failure and sinus rhythm and healthy controls.
Material and Methods
A total of 33 dogs were divided into three groups: dogs with chronic heart failure and atrial fibrillation (CHF + AF; n = 12), chronic heart failure and sinus rhythm (CHF + SR; n = 9), and healthy controls (n = 12). Serum total antioxidant capacity (TAC), serum CuZn-superoxide dismutase (SOD) and catalase, and plasma glutathione peroxidase (GPx) activity were determined.
SOD activity and serum TAC were significantly lower in the study groups than in control animals. Catalase activity was significantly higher and plasma GPx activity significantly lower in dogs with CHF + AF compared with the CHF + SR and control dogs.
The results suggest that chronic heart failure in dogs significantly impacts the serum TAC and the antioxidant enzymatic defence, while plasma GPx activity is markedly lower in dogs with chronic heart failure and atrial fibrillation. The role of that imbalance needs further investigation.
The aim of the study was to estimate prevalence of tricuspid dysplasia (TD) in dogs with respect to breed, age, sex, clinical signs, and echocardiographic findings and to compare this data with literature. TD was found in 15 dogs (6.5% of congenital cardiac disease) of 215 dogs with congenital heart defects. All dogs had right heart enlargement on thoracic radiographs, echocardiography, and electrocardiography. Doppler echocardiography revealed tricuspid valve regurgitation. Seven dogs presented no clinical symptoms to date. TD took the form of Ebstein anomaly in all Labrador Retrievers, one Boxer, and one German Shepherd dog. TD predominated in males (11 males vs. three females). The body weight of the affected dogs, with the exception of the Miniature Schnauzer, exceeded 20 kg. Two dogs (Boxer and Bull Terrier) had additional congenital cardiac lesions in the form of mitral valve dysplasia. The most affected breeds in the study were the Labrador Retriever and Boxer.