Veterinary echocardiographers' preferences for left atrial size assessment in dogs: the BENEFIT project

Left atrial volume and function in Cavalier King Charles spaniels at different ACVIM stages

BACKGROUND

The correct assessment of left atrial size and function is essential to evaluate the severity of degenerative mitral valve disease in dogs.

HYPOTHESIS/OBJECTIVES

Evaluate left atrial (LA) dimension and function in Cavalier King Charles Spaniel (CKCS) at different ACVIM stages and the accuracy of linear and volumetric indexes to assess LA enlargement.

ANIMALS

One hundred and ninety-eight privately owned CKCS.

METHODS

Multicentric prospective observational cross-sectional study. Dogs underwent an echocardiographic exam for breed screening or cardiac examination. Linear and volumetric echocardiographic LA size and function indexes were compared between classes.

RESULTS

Dogs were allocated as follows: 43 in class ACVIM A, 58 ACVIM B1, 55 ACVIM B2, and 42 ACVIM C/D. Only LA anteroposterior diameter normalized on body weight (LADn) and LA maximal, minimal and P volumes (LAVmax, LAVmin, LAVP) differed across all pairwise comparisons. Active LA emptying fraction (aLAEF) was higher in class B1 compared to class A (P < .001), and then decreased in class C/D compared to class B2 (P < .001). This suggests an increase in the left atrial active component due to the Frank-Starling mechanism in ACVIM B1 dogs, and the presence of atrial dysfunction in symptomatic dogs.

CONCLUSIONS AND CLINICAL IMPORTANCE

The LADn and LAV are higher in CKCS in class ACVIM B1 compared to class ACVIM A, suggesting the presence of LA remodelling at the early stages of the disease. Atrial dysfunction is evident in symptomatic dogs.

Risk Factors for Atrial Fibrillation in the Dog: A Systematic Review

Different risk factors for atrial fibrillation (AF) development have been identified in numerous studies on humans, but this information is less clearly available on the dog. The aim of this systematic review is to determine the risk factors for AF in the dog. Following the PRISMA 2020 guidelines, we conducted a comprehensive search using the Web of Science and Scopus databases for articles reporting on cases of spontaneously occurring AF in dogs. The level of evidence was assessed using the Evidence Quality Grading System of the National Institute of Health. One thousand forty-three studies were initially identified, and twenty of them were included in this systematic review involving 2,359,275 dogs, of which 4807 showed spontaneously occurring AF. Genetics, for the Irish Wolfhound, increased body weight, and left atrial enlargement were the main risk factors for the development of AF in dogs with different cardiac diseases, particularly myxomatous mitral valve disease (MMVD) and dilated cardiomyopathy (DCM). However, some differences were found between these two cardiac diseases regarding additional risk factors. In particular, the presence of congestive heart failure and echocardiographic evidence of increased left atrial pressure or the presence of right atrial enlargement emerged as risk factors in dogs with MMVD or DCM, respectively. Furthermore, significant differences in risk factors were observed between dogs and humans. In particular, advanced age and male sex are not reliable indicators of an increased risk of AF in dogs.