Galectin-3 (Gal-3) is a lectin associated with fibrosis and inflammation, and increased circulating concentrations are considered a risk factor for atrial fibrillation (AF) in humans. This retrospective study aimed to evaluate the serum concentration of Gal-3 in dogs with cardiac disease, both with and without AF. Dogs with AF associated with acquired heart diseases were selected, while cardiac healthy dogs and dogs with heart diseases but without AF served as controls. We statistically compared the serum concentration of Gal-3, which was assessed using a commercial canine-specific ELISA kit, among healthy dogs and dogs with heart disease with and without AF. Additionally, associations between Gal-3 and clinical and echocardiographic variables were evaluated. A total of 73 dogs were included, of which 17/73 (23.3%) were cardiac healthy and 56/73 (76.7%) had heart disease, with 26/56 (46.4%) having AF. No significant difference in Gal-3 concentration was found between cardiac healthy dogs (3.90 ± 1.65 ng/mL) and dogs with heart disease, either with or without AF (3.37 ± 1.04 ng/mL, p = 0.436 and 4.68 ± 1.80 ng/mL, p = 0.332, respectively). Gal-3 showed a significant positive correlation with age (r = 0.47, p < 0.001) and a negative correlation with body weight (r = −0.45, p < 0.001). The results of this study suggest that Gal-3 does not have an important role in the development of AF in dogs, but it is associated with advanced age.

Atrial fibrillation (AF) and ventricular arrhythmias (VAs) are common pathological arrhythmias of dogs and are both associated with a poor prognosis in those with cardiac disease. This study aimed to assess the ability of 2 to 5 min electrocardiography (routine ECG) to detect the presence and severity of concomitant VAs in dogs with secondary AF. Continuous 24 h ECG monitoring (Holter) was used as the reference standard to identify VAs, quantify the number of premature ventricular ectopic complexes (VPCs) and evaluate the degree of their organization using a modified Lown–Wolf classification scale. In light of the Holter findings, VAs were classified as severe based on two criteria: the presence of more than 100 VPCs and a Lown–Wolf grade ≥ 4. Thirty-five dogs with secondary AF were included, where all exhibited VAs on Holter monitoring. Most dogs had severe VAs, according to both the VPC count (69%) and Lown–Wolf classification (77%). However, only 13 dogs (37%) had VAs detectable on routine ECG. A significant positive correlation was found between the presence of VAs on routine ECG and the severity of VAs identified via Holter. Nevertheless, the diagnostic accuracy of routine ECG in predicting severe VAs was only moderate (68.6% based on VPC count and 60% based on Lown–Wolf grade). Overall, a 2 to 5 min ECG appears to be a highly specific but relatively insensitive tool for detecting VAs in dogs with secondary AF.

Dogs with acute congestive heart failure (CHF) can develop acute kidney injury (AKI); the prevalence of this condition has not been defined. This study aimed to assess the occurrence of AKI (increase in serum creatinine (sCr) ≥ 0.3 mg/dL) within 48 h from admission in dogs with myxomatous mitral valve disease (MMVD) with acute CHF, and the role of urinary neutrophil gelatinase-associated lipocalin (uNGAL) as a predictive marker of AKI. This was a multicentric, prospective observational study. Thirty dogs were included. The types and dosages of the diuretics administered, as well as the serum and urinary chemistry, including uNGAL and uNGAL, to the urinary creatinine ratio (uNGALC), were determined at admission (T0) and after 24 (T24) and 48 (T48) hours of hospitalization. Nineteen dogs developed AKI. We found no statistically significant differences in sCr, uNGAL, uNGALC, diuretic dosage, or hours of hospitalization between dogs that developed AKI and those that did not. The urinary NGAL and uNGALC values were not statistically significantly different at any time point, while the sCr was higher at T24 and T48 than T0. Our findings suggest that AKI in MMVD dogs with CHF is primarily functional, driven by effective decongestion rather than severe tubular damage, with the benefits of decongestion outweighing transient increases in sCr.

Galectin-3 (Gal-3) is a lectin associated with fibrosis and inflammation, and increased circulating concentrations are considered a risk factor for atrial fibrillation (AF) in humans. This retrospective study aimed to evaluate the serum concentration of Gal-3 in dogs with cardiac disease, both with and without AF. Dogs with AF associated with congenital and acquired heart diseases were selected, while clinically healthy dogs and dogs with heart diseases but without AF served as controls. We statistically compared the serum concentration of Gal-3, assessed using a commercial canine-specific ELISA kit, among healthy dogs and dogs with heart disease with and without AF. Additionally, associations between Gal-3 and clinical and echocardiographic variables were evaluated. A total of 80 dogs were included, of which 17/80 (21.2%) were clinically healthy and 63/80 (78.8%) had heart disease, with 30/63 (47.6%) having AF. No significant difference in Gal-3 concentration was found between healthy dogs (3.90 ± 0.38 ng/mL) and dogs with heart disease, either with or without AF (3.45 ± 0.28 ng/mL, P=0.226 and 4.46 ± 0.27 ng/mL, P=0.286, respectively). Gal-3 showed a significant positive correlation with age (r=0.46, P < 0.001). The results of this study suggest that Gal-3 does not have predictive value for the development of AF in dogs, but it is associated with advanced age.

Atrial fibrillation (AF) and ventricular arrhythmias (VAs) are common pathological arrhythmias of dogs and are both associated with a poor prognosis in those with cardiac disease. This study aimed to assess the ability of 2- to 5-minute electrocardiography (routine ECG) to detect the presence and severity of concomitant VAs in dogs with secondary AF. Continuous 24-hour ECG monitoring (Holter) was used as the reference standard to identify VAs, quantify the number of premature ventricular ectopic complexes (VPCs) and evaluate the degree of their organization using a modified Lown-Wolf classification scale. In light of the Holter findings, VAs were classified as severe based on two criteria: the presence of more than 100 VPCs and a Lown-Wolf grade ≥4. Thirty-five dogs with secondary AF were included; all exhibited VAs on Holter monitoring. Most dogs had severe VAs, according to both the VPCs count (69%) and Lown-Wolf classification (77%). However, only 13 dogs (37%) had VAs detectable on routine ECG. A significant positive correlation was found between the presence of VAs on routine ECG and the severity of VAs identified via Holter. Nevertheless, the diagnostic accuracy of routine ECG in predicting severe VAs was only moderate (68.6% based on VPCs count and 60% based on Lown-Wolf grade). Overall, a 2- to 5-minute ECG appears to be a highly specific but relatively insensitive tool for detecting VAs in dogs with secondary AF.