Evidence for chronic inflammation in cats with cardiomyopathies

Area of Science:

• Veterinary Internal Medicine
• Cardiology
• Immunology

Background:

• Feline cardiomyopathy is a significant cardiac disease in cats.
• Inflammation is suspected to play a role in the pathogenesis of feline cardiomyopathies.
• Complete blood count (CBC)-derived inflammatory markers may offer insights into disease activity.

Purpose of the Study:

• To investigate inflammation using CBC and derived markers (neutrophil:lymphocyte ratio [NLR], monocyte:lymphocyte ratio [MLR], systemic inflammation response index [SIRI]) in cats with American College of Veterinary Internal Medicine (ACVIM) stages B and C cardiomyopathy versus healthy controls.
• To compare CBC and derived inflammatory markers between cats with cardiogenic pleural effusion and cardiogenic pulmonary edema.

Main Methods:

• Comparative study involving 66 cats with cardiomyopathy (ACVIM B and C) and 24 healthy cats.
• Statistical analysis included ANCOVA (with age as covariate) for group comparisons and t-tests/Mann-Whitney tests for effusion type comparisons.
• Evaluated white blood cell count, neutrophil count, NLR, MLR, and SIRI.

Main Results:

• Cats in ACVIM C stage showed significantly higher white blood cell and neutrophil concentrations than ACVIM B and control groups.
• ACVIM C cats had significantly elevated NLR, MLR, and SIRI compared to healthy cats.
• ACVIM B cats exhibited significantly higher NLR and SIRI than healthy cats. No significant differences in inflammatory markers were found between pleural effusion and pulmonary edema.

Conclusions:

• Results support the presence of systemic inflammation in feline cardiomyopathies, particularly in advanced (ACVIM C) stages.
• CBC-derived inflammatory markers, including NLR and SIRI, are elevated in feline cardiomyopathy.
• The type of fluid accumulation (pleural effusion vs. pulmonary edema) did not correlate with differences in measured inflammatory markers.