Associations among echocardiography, cardiac biomarkers, insulin metabolism, morphology, and inflammation in cats with asymptomatic hypertrophic cardiomyopathy

Abstract

Background Insulin, insulin‐like growth factor‐1 (IGF‐1), and inflammation possibly are involved in cats with asymptomatic hypertrophic cardiomyopathy (aHCM). Objectives To evaluate echocardiography, morphology, cardiac and inflammatory markers, insulin and IGF‐1 in cats with aHCM. Animals Fifty‐one client‐owned cats with aHCM. Methods Observational descriptive study. Variables (body weight [BW], body condition score [BCS], echocardiography, and serum concentrations of N‐terminal pro‐B‐type natriuretic peptide [NT‐proBNP], ultra‐sensitive troponin‐I [c‐TnI], serum amyloid A [SAA], insulin, glucose and IGF‐1) were evaluated for significant increases above echocardiography cutoff values and laboratory reference ranges, associations and effect of left atrial (LA) remodeling and generalized hypertrophy. Results Cats with aHCM had BCS ≥6/9 (P = .01) and insulin (P < .001), NT‐proBNP (P = .001) and cTn‐I (P < .001) above laboratory reference ranges. Associations were present between NT‐proBNP and maximum end‐diastolic interventricular septum thickness (IVSd; ρ = .32; P = .05), maximum end‐diastolic left ventricular free wall thickness;(ρ = .41; P = .01), LA/Aorta (ρ = .52; P = .001) and LA diameter (LA‐max; ρ = .32; P = .05); c‐TnI and LA/Aorta (ρ = .49; P = .003) and LA‐max (ρ = .28; P = .05); and SAA and number of IVSd regions ≥6 mm thickness (ρ = .28; P = .05). Body weight and BCS were associated with IGF‐1 (r = 0.44; P = .001), and insulin (ρ = .33; P = .02), glucose (ρ = .29; P = .04) and IGF‐1 (ρ = .32; P = .02), respectively. Concentrations of NT‐proBNP (P = .02) and c‐TnI (P = .01), and SAA (P = .02), were higher in cats with LA remodeling, and generalized hypertrophy, respectively. Conclusions and clinical importance Results suggest potential implications of insulin, IGF‐1, and inflammation in cats with aHCM, but it remains to be confirmed whether these findings represent a physiological process or a part of the pathogenesis and development of disease.

Evaluation of cardiac troponin I as a predictor of death in critically ill cats

“…Of the 27 cats with structural cardiac disease, 15 were hospitalized because of noncardiac disease, with the cardiac condition discovered only owing to the study protocol (echocardiography). Also, 17/27 cats with cardiac disease had a concurrently abnormally high SAA concentration, which is comparably uncommon in cats with HCM, and only described in 5/37 and 1/51 of cats in 2 previous studies 33,34 . Finally, the 2 cats in the cardiac group with the highest cTnI concentrations were not in CHF.…”

“…Also, 17/27 cats with cardiac disease had a concurrently abnormally high SAA concentration, which is comparably uncommon in cats with HCM, and only described in 5/37 and 1/51 of cats in 2 previous studies. 33,34 Finally, the 2 cats in the cardiac group with the highest cTnI concentrations were not in CHF. Hence, comorbidities are a likely cause of the pronounced myocardial injury, (most likely because of hypoxia, cytokine-mediated cellular injury, or myocardial infarction), seen in the cats with structural cardiac disease in this study.…”

Updates on Laboratory Evaluation of Feline Cardiac Diseases

“…It is uncertain whether this relationship is only present in cats with asymptomatic hypertrophic cardiomyopathy (HCM), or if it is related to the pathophysiology of the illness. Inflammation has been associated with congestive heart failure (CHF) in diverse species and cardiac diseases [ 13 ].…”

“…Conversely, IGF-1 was not found to be significantly increased, even though some cats had high IGF-1 concentrations. Furthermore, no association was found between echocardiographic parameters, insulin or IGF-1 and cardiac biomarkers, leaving the role of insulin and IGF-1 uncertain in cats with HCM [ 13 ]. Cardiovascular abnormalities (e.g., left ventricular concentric hypertrophy, left atrial enlargement, and abnormal diastolic function) are often present in cats with acromegaly (hypersomatotropism) caused by functional somatotropic adenoma or hyperplasia of the pituitary gland.…”

“…In cats, various studies were performed comparing healthy subjects to patients with echocardiographic evidence of cardiac disease. These studies demonstrated significantly higher circulating troponin concentrations in cats with HCM and also in asymptomatic subjects [ 13 , 91 , 92 , 93 , 94 , 95 ]. Interestingly, an ultra-sensitive measurement method used in humans to measure cTnI concentration has been tested in cats showing to be applicable in these subjects [ 93 , 94 , 95 ].…”