Frequency of arrhythmias detected in 9440 feline electrocardiograms by breed, age, and sex.

OBJECTIVES: The purpose of this study was to describe the frequency of arrhythmias detected in unsedated feline patients from general practice settings. ANIMALS: A total 10,638 feline electrocardiograms (ECGs) were retrospectively collected of which 9440 met the inclusion criteria. METHODS: Recordings were evaluated by a board-certified cardiologist. If an arrhythmia was present in the ECG tracing, the cardiologist categorized the arrhythmia using pre-established keywords. RESULTS: At least one arrhythmia was observed in 249 cases (2.64%, 95% confidence interval (CI): 2.34-2.98, 249/9440), with the most common arrhythmia encountered being ventricular premature complexes (1.63%, 95% CI: 1.39%-1.91%, 154/9440). Ragdoll cats had the highest odds of arrhythmia (odds ratio (OR): 3.17, 95% CI: 1.43-6.17, P=0.036). Both geriatric (Age: 13+ years, OR: 1.70, 95% CI: 1.24-2.34, P=0.013) and senior (Age: 10-13 years, OR: 1.68, 95% CI: 1.19-2.37, P=0.003) cats had higher odds of having an arrhythmia than adult cats. The odds of male cats having an arrhythmia were slightly higher than female (OR: 1.36, 95% CI: 1.06-1.76, P=0.018). CONCLUSIONS AND RELEVANCE: Of the 9440 ECGs included in this study, at least one arrhythmia was detected in 249 distinct cases. Arrhythmias were more common in older cats, male cats and the Ragdoll cat breed. While it is important to note that the presence of an arrhythmia alone does not always indicate the presence of heart disease, further research on the association between breed cardiac health is needed.

Diagnostic accuracy of computer aided electrocardiogram analysis in dogs.

OBJECTIVES: Evaluation of a computerised electrocardiogram algorithm compared to the interpretation of a team of board-certified veterinary cardiologists. MATERIALS AND METHODS: This was a cross-sectional retrospective cohort study. A total of 399 electronic canine electrocardiogram recordings screened from 1391 electrocardiograms were enrolled in the study. A panel of seven cardiologists, masked to patient information, evaluated electrocardiograms for the following: P-wave amplitude and duration; PR-interval; R-wave amplitude; QRS duration; heart rate; mean electrical axis; and final overall diagnosis for the detection of arrhythmia and any abnormal electrocardiogram anomaly. RESULTS: The sensitivity of the electrocardiogram algorithm for detecting arrhythmias was 99.7% (95% confidence intervals, CI: 98.5 to 99.9) and the specificity was 99.5% (95% CI: 98.0 to 99.9) compared to the consensus result created by panel of cardiologists. The sensitivity of the algorithm for the detection of any electrocardiogram anomaly, including abnormal measurements, was 71.3% (95% CI: 65.5 to 76.7) and the specificity was 35.1% (95% CI: 27.0 to 43.8) compared to the panel of cardiologists. CLINICAL SIGNIFICANCE: The electrocardiogram algorithm was shown to have high sensitivity for the detection of arrhythmias, but not all electrocardiogram anomalies. The results support the use of this algorithm as a tool to aid in the triage of the electrocardiogram workflow.

Measurement Variation and Repeatability of Echocardiographic Variables Used to Estimate Pulmonary Artery Pressure in Dogs.

BACKGROUND: Pulmonary hypertension (PH) is an important clinical entity in dogs. Pulmonary hypertension is generally identified based on echocardiographic findings, but measurement variation of the variables most often used in this context has not been reported. OBJECTIVE: To define measurement variation of echocardiographic variables that are used to estimate pulmonary artery pressure. ANIMALS: Four dogs with subclinical tricuspid valve regurgitation were selected from a hospital population. METHODS: Prospective descriptive study - dogs were subject to repeated echocardiographic examination by 2 operators. Each dog was echocardiographically examined 12 times, once by each operator during mornings and afternoons of 3 nonconsecutive days. Measurement variation was defined by coefficients of variation and by mean square errors (MSE) from ANOVA models. Repeatability coefficients (RC) were calculated from MSE. RESULTS: Of 50 within-day, between-day, and interoperator coefficients of variation (CVs), 37 were less than 10% and 46 were less than 15%. The range of peak velocity of tricuspid valve regurgitation (VTR) VTR was 1.87-3.34 m/s. Analysis of variance revealed a significant effect (P < 0.05) of operator for 7 of 10 measurements. Within-operator/between-day/within-subject and between-operator/between-day/within-subject RCs of VTR were, respectively, 0.3 and 0.6 m/s. CONCLUSIONS AND CLINICAL IMPORTANCE: With regard to repeatability, VTR is superior to other methods used for echocardiographic estimation of systolic pulmonary artery pressure. When TR is absent, the acceleration time of pulmonary ejection and the acceleration-to-ejection time ratio are alternative measures. A change in VTR exceeding 0.3 m/s might be outside the range of expected within-operator variation.

Conventional echocardiographic assessment of the canine right heart: reference intervals and repeatability.

INTRODUCTION: We sought to define reference intervals for echocardiographic dimensions of the canine right heart. Secondarily, we intended to describe measurement variability of these dimensions. ANIMALS: Forty-five healthy adult pet dogs of diverse somatotype. MATERIALS AND METHODS: To obtain normative data used to define reference intervals, dogs underwent one echocardiographic examination by the same operator. Raw data were subject to logarithmic (log10) transformation and allometric relationships between body weight and echocardiographic variables were determined; reference intervals intended to include 95% of the population were defined. Six of the 45 dogs were randomly selected and subject to repeated echocardiographic examination by two operators. Measurement variability was quantified through calculation of coefficients of variation and repeatability coefficients. RESULTS: The strength of the linear relationships between log10 transformed echocardiographic variables and body weight varied; the range of coefficients of determination (R(2)) was 0.055-0.872. For most variables the scaling exponents were close to values expected based on presumed allometric relationships. Of the 190 within-day, between-day and inter-operator coefficients of variation generated, 165 (87%) were less than 15%. Analysis of variance revealed the operator to be a significant source of variation for 25 of 38 measurements. CONCLUSIONS: Reference intervals for echocardiographic dimensions and indices of right heart function are proposed. Repeatability of selected linear dimensions and areas obtained from two-dimensional echocardiography likely is sufficient for longitudinal clinical evaluations.