Feline leukemia virus (FeLV) is responsible for feline leukemia syndrome in domestic cats. The prevention and control of disease caused by FeLV are primarily based on vaccination and identification and isolation of infected subjects. Antigen diagnostic methods, which are the most widely used in clinical practices, can be associated to molecular tests to characterize the FeLV detected. In this study, a quantitative SYBR Green Real-Time PCR (qPCR) assay was used to detect FeLV proviral DNA in blood samples from antigen positive cats referred to a veterinary teaching hospital in Northern Italy in 2018–2021. To genetically characterize the identified viruses, a portion of the viral envelope (env) gene was amplified using six different end-point PCRs and sequenced. Twenty-two of 26 (84.6%) cats included in the study tested positive by qPCR assay. This suggests a high performance of the qPCR adopted but further studies are required to investigate the cause of discordant results between the antigen test and qPCR in four cats. From env gene analysis, 15/22 qPCR-positive cats were infected by FeLV subtype A and 5/15 shown coinfection with subtype B.

In dogs, myocardial injury (MI) is a poorly characterized clinical entity; therefore, this study aimed to provide a detailed description of dogs affected by this condition. Dogs diagnosed with MI according to the concentration of cardiac troponin I (cTnI) were retrospectively searched. Signalment, diagnostic, therapeutic, and outcome data were retrieved. Dogs were divided into six echocardiographic (dilated cardiomyopathy phenotype; hypertrophic cardiomyopathy phenotype; hypertrophic cardiomyopathy phenotype with systolic dysfunction; abnormal echogenicity only; endocarditis; and no echocardiographic abnormalities suggestive of MI), four electrocardiographic (abnormalities of impulse formation; abnormalities of impulse conduction; abnormalities of ventricular repolarization; and no electrocardiographic abnormalities suggestive of MI), and nine etiological (infective; inflammatory; neoplastic; metabolic; toxic; nutritional; immune-mediated; traumatic/mechanical; and unknown) categories. Statistical analysis was performed to compare cTnI values among different categories and analyze survival. One hundred two dogs were included. The median cTnI value was 3.71 ng/mL (0.2-180 ng/mL). Echocardiographic and electrocardiographic abnormalities were documented in 86 of 102 and 89 of 102 dogs, respectively. Among echocardiographic and electrocardiographic categories, the dilated cardiomyopathy phenotype (n = 52) and abnormalities of impulse formation (n = 67) were overrepresented, respectively. Among dogs in which a suspected etiological trigger was identified (68/102), the infective category was overrepresented (n = 20). Among dogs belonging to different echocardiographic, electrocardiographic, and etiological categories, cTnI did not differ significantly. The median survival time was 603 days; only eight of 102 dogs died due to MI. Dogs with MI often have an identifiable suspected trigger, show various echocardiographic and electrocardiographic abnormalities, and frequently survive to MI-related complications.

Background: No previous study has evaluated the accuracy of a six‐lead smartphone‐based electrocardiographic (s‐ECG) device in dogs. Methods: This was a prospective multicentre study. Patients referred for cardiologic consultation were selected. In each patient, a 30‐second electrocardiogram was simultaneously acquired with a novel six‐lead s‐ECG and a standard six‐lead ECG machine (st‐ECG). A board‐certified cardiologist evaluated each recording. Nineteen ECG variables, including heart rate and rhythm, as well as quantitative and qualitative features of waves, segments and intervals, were analysed. Agreement between s‐ECG and st‐ECG was evaluated using Cohen's kappa coefficient and the Bland–Altman test. Results: Seventy‐five dogs were enrolled, and 140 ECG tracings were analysed. There was perfect agreement between the two methodologies for heart rate and rhythm classification, both in dogs with sinus rhythm and those with pathological rhythms. Although some disagreement was found when comparing measurements of quantitative variables obtained with the s‐ECG and the st‐ECG, none of the differences was of clinical relevance. Limitations: The sample size was limited, and the interobserver variability was not analysed. Conclusion: The six‐lead s‐ECG studied herein is comparable to the st‐ECG for heart rate and rhythm assessment, and seems clinically acceptable for the interpretation of waves, segments and intervals in dogs.