Cardiomyopathy In Cats Research Articles

Evaluation of potential novel biomarkers for feline hypertrophic cardiomyopathy

Hypertrophic cardiomyopathy (HCM) is the most common cardiomyopathy in cats. The diagnosis can be difficult, requiring advanced echocardiographic skills. Additionally, circulating biomarkers (N-terminal pro-B type natriuretic peptide and cardiac troponin I) have several limitations when used for HCM screening. In previous work, we identified interleukin 18 (IL-18), insulin-like growth factor binding protein 2 (IGFBP-2), brain-type glycogen phosphorylase B (PYGB), and WNT Family Member 5 A (WNT5A) as myocardial genes that show significant differential expression between cats with HCM and healthy cats. The products of these genes are released into the circulation, and we hypothesized that IL-18, IGFBP-2, PYGB, and WNT5A serum RNA and protein concentrations differ between healthy cats, cats with subclinical HCM, and those with HCM and congestive heart failure (HCM + CHF).Reverse transcriptase quantitative polymerase chain reaction (RTqPCR) and enzyme-linked immunosorbent assay (ELISA) were applied to evaluate gene and protein expression, respectively, in the serum of eight healthy controls, eight cats with subclinical HCM, and six cats with HCM + CHF. Serum IGFBP-2 RNA concentrations were significantly different among groups and were highest in cats with subclinical HCM. Compared to healthy controls, serum IL-18 and WNT5A gene expression were significantly higher in cats with HCM + CHF, and WNT5A was higher in cats with subclinical HCM. No differences were observed for PYGB.These results indicate that further investigation via large scale clinical studies for IGFBP-2, WNT5A, and IL-18 may be valuable in diagnosing and staging feline HCM.

Genetic Basis of Hypertrophic Cardiomyopathy in Cats.

Hypertrophic cardiomyopathy (HCM) is a common cardiovascular condition in cats, affecting yth males and females of all ages. Some breeds, such as Ragdolls and Maine Coons, can develop HCM at a young age. The disease has a wide range of progression and severity, characterized by various pathological changes in the heart, including arteritis, fibrous tissue deposition, and myocardial cell hypertrophy. Left ventricular hypertrophy, which can restrict blood flow, is a common feature of HCM. The disease may persist into old age and eventually lead to heart failure and increased diastolic pressure. The basis of HCM in cats is thought to be genetic, although the exact mechanisms are not fully understood. Mutations in sarcomeric proteins, in particular myosin-binding protein C (MYBPC3), have been identified in cats with HCM. Two specific mutations, MYBPC3 [R818W] and MYBPC3 [A31P], have been classified as 'pathogenic'. Other variants in genes such as MYBPC3, TNNT2, ALMS1, and MYH7 are also associated with HCM. However, there are cases where cats without known genetic mutations still develop HCM, suggesting the presence of unknown genetic factors contributing to the disease. This work aims to summarise the new knowledge of HCM in cats and the alterations in cardiac tissue as a result of genetic variants.

Parameters related to diagnosing hypertrophic cardiomyopathy in cats

Background: The initial diagnostic markers are important for general practitioners to identify cats suspected of having cardiac disease, particularly hypertrophic cardiomyopathy (HCM). Aim: The aim of this study is to investigate the indicators that suggest feline cardiac disease, especially HCM. Methods: This is a retrospective study, using the data from 354 cats, to identify various clinical parameters that indicate the presence of cardiac disease in cats in order to develop a model to predict the likelihood of HCM in cats. Among all the parameters gathered, heart sound and LA size are the most significant in predicting the likelihood of HCM in cats. Results: After undergoing statistical analysis, we created a formula that could help screening cats with HCM and normal cats before further diagnosis, such as echocardiography. The formula Y1 = -3.637 +2.448(LA size) +2.683(murmur) +1.274(gallop) is the fittest model with an AUC from the ROC analysis of 0.889. A new set of data was used to validate the model. This predictive model has 40% accuracy but correctly predicts 90% of the truely normal cats, making this model be beneficial in helping veterinarians exclude truly normal cats from cats suspected of having HCM. Conclusion: The model may assist in distinguishing normal cats from those suspected of having HCM. Further diagnosis with echocardiography remains the gold standard for the final diagnosis of cardiac diseases in cats.

Multi-Omic, Histopathologic, and Clinicopathologic Effects of Once-Weekly Oral Rapamycin in a Naturally Occurring Feline Model of Hypertrophic Cardiomyopathy: A Pilot Study.

Hypertrophic cardiomyopathy (HCM) remains the single most common cardiomyopathy in cats, with a staggering prevalence as high as 15%. To date, little to no direct therapeutical intervention for HCM exists for veterinary patients. A previous study aimed to evaluate the effects of delayed-release (DR) rapamycin dosing in a client-owned population of subclinical, non-obstructive, HCM-affected cats and reported that the drug was well tolerated and resulted in beneficial LV remodeling. However, the precise effects of rapamycin in the hypertrophied myocardium remain unknown. Using a feline research colony with naturally occurring hereditary HCM (n = 9), we embarked on the first-ever pilot study to examine the tissue-, urine-, and plasma-level proteomic and tissue-level transcriptomic effects of an intermittent low dose (0.15 mg/kg) and high dose (0.30 mg/kg) of DR oral rapamycin once weekly. Rapamycin remained safe and well tolerated in cats receiving both doses for eight weeks. Following repeated weekly dosing, transcriptomic differences between the low- and high-dose groups support dose-responsive suppressive effects on myocardial hypertrophy and stimulatory effects on autophagy. Differences in the myocardial proteome between treated and control cats suggest potential anti-coagulant/-thrombotic, cellular remodeling, and metabolic effects of the drug. The results of this study closely recapitulate what is observed in the human literature, and the use of rapamycin in the clinical setting as the first therapeutic agent with disease-modifying effects on HCM remains promising. The results of this study establish the need for future validation efforts that investigate the fine-scale relationship between rapamycin treatment and the most compelling gene expression and protein abundance differences reported here.

Acute heart failure and cardiogenic arterial thromboembolism in cats: clinical and echocardiographic features

Acute heart failure and arterial thromboembolism are common complications of hypertrophic cardiomyopathy in cats. These conditions have many common links in pathogenesis, so analyzing the differences between them improves the understanding of the impact of vessel occlusion on the body. In the study, 40 clinical cases were analyzed and two groups were formed: the first – cats with arterial thromboembolism and the second – cats with acute heart failure. The data from anamnesis, clinical examination and echocardiographic examination were collected. Age, sex, breed, weight, temperature, frequency of respiratory movements, signs of dyspnea, presence of pulmonary edema, presence of free fluid in the chest and pericardial cavities were analyzed. The following echocardiographic parameters were analyzed: left ventricular wall thickness, left ventricular end-systolic and end-diastolic dimensions, diameters of the aorta and left atrium, heart rate and left ventricular contraction fraction. It was established that the majority of animals from both groups were males. Acute heart failure was registered mainly in young cats (M = 3.7), in contrast to animals with arterial thromboembolism (M = 6.7), (P < 0.01). There was no significant difference in the values of rectal temperature, weight, heart rate, aortic diameter, and left ventricular contraction fraction. Most animals from both groups had signs of dyspnoea. The difference in the frequency of respiratory movements was significant (P < 0.01). In cats with acute heart failure, pulmonary edema was diagnosed in 85%, free fluid in the thoracic and/or pericardial cavities in 55 %. In animals with thromboembolism, edema was found in 45 %, and effusion in the chest and/or pericardial cavities in 30 % of animals. The established differences indicate that arterial thromboembolism develops in animals that have had heart pathology for a longer period of time, whereas acute heart failure occurs more suddenly in cats.

Circulating neutrophil extracellular traps in cats with hypertrophic cardiomyopathy and cardiogenic arterial thromboembolism.

Cats with hypertrophic cardiomyopathy (HCM) are at risk of cardiogenic arterial thromboembolism (CATE). Neutrophil extracellular traps (NETs) may be a potential biomarker and therapeutic target for cardiomyopathy in cats. Characterize NETs in cats with HCM or CATE. We hypothesized that circulating NETs assessed in the form of cell-free DNA (cfDNA) and citrullinated histone H3 (citH3) are increasedin cats with HCM and CATE and associated with reported predisposing factors for thrombus formation. Eighty-five cats including client-owned cats with HCM and CATE and staff- and student-owned clinically healthy cats without HCM. After echocardiographic evaluations, NETs were measured as cfDNA and citH3. Cats with CATE had significant increases in cfDNA (11.2ng/μL; interquartile range [IQR],8.1 to 29.6) compared to those without HCM (8.2ng/μL; IQR,5.7 to 11.7μL; P=.01) and were responsible for 75% to 83% of cases with cfDNA fragments sized 100 to 2000 base pairs. Citrullinated histone 3, detected in 52% of cats with HCM (31.1ng/mL; IQR, 16.9 to 29.8), was significantly lower than in those with CATE (48.2ng/mL; IQR, 34.2 to 60.2; P=.007). The citH3 concentrations correlated significantly with reported risk factors of CATE, such as left atrial auricular velocity. Neutrophil extracellualr traps, especially citH3, are increased in cats with HCM and CATE. They may serve as a novel therapeutic target and biomarker of thrombosis in cats with HCM.

Comparison of echocardiography, biomarkers and taurine concentrations in cats eating high- or low-pulse diets.

There are ongoing investigations into diet-associated dilated cardiomyopathy in dogs, but there has been minimal investigation into possible diet-associated dilated cardiomyopathy in cats. The objective of this study was to compare cardiac size and function, cardiac biomarkers and taurine concentrations in healthy cats eating high- vs low-pulse diets. We hypothesized that cats eating high-pulse diets would have larger hearts, lower systolic function and higher biomarker concentrations than cats eating low-pulse diets and that there would be no difference in taurine concentrations between the diet groups. Echocardiographic measurements, cardiac biomarkers, and plasma and whole-blood taurine concentrations were compared between cats eating high- and low-pulse commercial dry diets in a cross-sectional study. There were no differences between the high- (n = 21) and low-pulse (n = 31) diet groups with regard to age, sex and breed, but more cats in the high-pulse group were overweight or obese (67% vs 39%; P = 0.05). Diet duration was not different in the groups, but the range was wide (6-120 months). No differences were found between the diet groups for key cardiac measurements, biomarker concentrations, or plasma or whole-blood taurine concentrations. However, there were significant negative correlations between diet duration and measures of left ventricular wall thickness in the high-pulse, but not the low-pulse, diet group. This study did not detect significant associations between high-pulse diets and cardiac size, function and biomarkers, but the secondary observation of significant negative correlations between time on high-pulse diets and left ventricular wall thickness warrants further evaluation.

EFFECTIVENESS OF PIMOBENDAN IN CATS WITH CARDIOGENIC ARTERIAL THROMBOEMBOLISM

Cardiogenic arterial thromboembolism (CATE) is a common complication of cardiomyopathy in cats. Current research is aimed at developing effective protocols for the therapy and prevention of CATE. The main focus is on finding effective anticoagulants, antiaggregants, and methods that improve blood supply to the affected area. At the same time, interest in the use of pimobendan for the therapy of congestive heart failure in cats has increased among researchers. Published works show an increase in life expectancy in cats with hypertrophic cardiomyopathy (HCM) and a positive effect on left atrial function. Therefore, the study of the effect of pimobendan on life expectancy, the occurrence of relapses in cats according to CATE is relevant and became the goal of this work. The study included 24 animals that had a CATE incident due to HCM and lived more than 2 weeks after the crisis. Two groups were formed: the first - 13 cats that after stabilization of the condition received standard therapy (furosemide, ACE inhibitor, clopidogrel) and pimobendan; the second - 11 cats that received only standard therapy. The anamnesis, clinical examination, echocardiographic examination, and information about relapse, death or euthanasia were recorded in the animals. 91.7% of cats were males, the average age was 7 ± 0.7 years. Dyspnoea, pulmonary edema, hypothermia, change in mental status, paresis and anemia of the affected limb were found in the majority. Two pelvic limbs were more often affected. Relapse occurred in 37.5% of subjects. The time interval from the incident to the recurrence in the first group was 387.4 ± 104.5 and in the second 107.2 ± 32.1 days. Euthanasia was performed for 20.8% of animals and was always associated with relapse. The survival time in the first group averaged 403.7 ± 104.0, and in the second - 314 ± 47.3 days. The median survival time for the first group is 9.5 months and for the second 12.5. After the death of all the animals in the first group, 40% of cats who received pimobendan remained alive. We didn`t find statistical differences between the groups in the number of relapses, euthanasias, duration of life and survival. Was found a significant difference in the length of time before relapse. Pimobendan did not show a negative effect on life expectancy in cats according to CATE. The positive effect is probably not clear enough and needs to be studied in a larger cohort of animals.

Natural history of hypertrophic cardiomyopathy in cats from rehoming centers: The CatScan II study.

The natural history of hypertrophic cardiomyopathy (HCM) in cats has been mainly studied in cats referred for suspected heart disease, which can skew the results towards cats with clinical signs. Few data are available on factors associated with development of HCM in cats. (1) Clinical variables can predict which cats will develop HCM; (2) HCM in cats not referred for suspected heart disease is associated with a low rate of cardiovascular events. One hundred seven cats from rehoming centers without a history of clinical signs of cardiac or systemic disease at the time of adoption. Prospective longitudinal study. After rehoming, shelter cats were reexamined for serial echocardiograms. Cox regression analysis was used to identify predictors of development of HCM in cats that were normal at baseline. Adverse cardiovascular events including heart failure, thromboembolism, or sudden death were recorded. Cats were monitored for a median of 5.6 [1.2-9.2] years. At baseline, 68/107 cats were normal, 18/107 were equivocal and 21/107 had HCM. Nineteen cats developed HCM during the study period. The factors at baseline associated with increased hazard of developing HCM were lower left atrial fractional shortening, higher left ventricular fractional shortening, and higher body weight. Cardiovascular events were observed in 21% of cats with HCM. Cardiovascular events were common in cats with HCM from a rehoming center study sample. Lower left atrial systolic function appears to precede overt HCM.

The Use of 3-D Models of Echocardiographic Imaging Planes for Teaching Echocardiography Techniques for Use in Dogs and Cats.

Echocardiography is an invaluable technique for the diagnosis of heart disease. The aim of this study was to develop 3-D models of healthy and diseased hearts of dogs and cats, and to evaluate their effectiveness in assisting veterinary undergraduates to understand echocardiographic imaging planes. Resin models depicting the main echocardiographic imaging planes of normal hearts were created, as well as example hearts with features of mitral degeneration in dogs and hypertrophic cardiomyopathy in cats. After a theoretical class, fourth-year students were randomly assigned to one of two groups (model group or control group). The model group had access to the 3-D models, along with self-explanatory text about echocardiographic imaging planes; the control group only had access to the self-explanatory text. Both groups were allowed 2weeks to study their allocated resources, after which the students undertook an assessment to evaluate their learning and completed a questionnaire about their experiences and satisfaction with the respective teaching method. A total of 39 students participated in the study, 19 in the model group and 20 in the control group. Students assigned to the model group spent more time studying (p = 0.0027). The proportion of students who achieved a satisfactory grade in the assessment was 89.5% in the model group and 60% in the control group (p = 0.0449). The 3-D models facilitated, and significantly improved, the identification of cardiac structures and disease-associated abnormalities, and the learning process in general. Additionally, the models seemed to provide greater student motivation for studying echocardiography.

Prognostic criteria for assessing of hypertrophic cardiomyopathy in cats

Hypertrophic cardiomyopathy (HCM) occurs in 10-15% of cats in the population [5, 7]. Cardiomyopathy is a myocardial disease in which the structure and function of the heart muscle are impaired in the absence of any other condition that could cause the observed deviation [10]. To assess the state of the cardiovascular system, echocardiography, electrocardiography, X-ray examination, as well as, importantly, physical examination are used in veterinary cardiology [1, 4, 5, 10]. Visual diagnostic techniques are the most objective and informative, however, it is the components of the physical examination and the timely response of the owner to deviations in the parameters of the physical examination that allows you to select and evaluate the effectiveness of the treatment of heart disease. Counting the number of respiratory movements at rest (during sleep) is one of the important criteria for physical examination available to the cat owner [9]. This indicator allows you to adjust the treatment, as well as predict the possible onset of deterioration. The aim of the presented study was to determine the main prognostic parameters in cats with congestive heart failure caused by HCMP stage C [10]. A group of 4 DSH cats was formed, in which hypertrophic cardiomyopathy stage C was detected (according to ACVIM staging). When assessing the main indicators, it was revealed that unfavorable prognostic signs are the diameter of the left atrium (correlation degree -0.62), the number of respiratory movements at rest - both before and after the start of treatment (correlation degree -0.77 and -0.81, respectively). It should also be noted a moderate positive correlation between the indicator of life expectancy and the fraction of contractility of the left atrium (0.39). However, it should be noted that in order to more accurately determine the diagnostic significance and the possibility of determining forecasts, it is necessary to increase the number of animal samples with an assessment of indicators in dynamics.

Methods for diagnosing of hypertrophic cardiomyopathy in cats

The article discusses the main diagnostic methods used in the diagnosis of hypotrophic cardiomyopathy in cats. The work was carried out on the basis of one of the veterinary clinics in St. Petersburg. Of the clinical symptoms, the most common are shortness of breath, cyanosis, weakness, breathing through the mouth. Systemic hypertension was diagnosed in sick cats. In hypertrophic cardiomyopathy of cats, echocardiography is still the gold standard of diagnosis, but it is worth noting that for an accurate diagnosis, one should not be limited to ultrasound examination of the heart, a comprehensive assessment of the clinical status of the animal should be carried out and the degree of negative effect of HCM on a particular patient should be determined.

Dilated cardiomyopathy in cats: survey of veterinary cardiologists and retrospective evaluation of a possible association with diet

Introduction/objectivesThe objectives were to conduct a survey of cardiologists on their recent experiences with cats that have dilated cardiomyopathy (DCM) and to retrospectively review individual cases of feline DCM. Animals, materials and methodsPart one: A survey was distributed to cardiologists with questions regarding caseload and clinical management of cats with DCM diagnosed over the past two years. Part two: Cardiologists completing the survey were invited to submit data from cats recently diagnosed with DCM. Data on signalment, clinical signs, diet, echocardiographic measurements and outcome were recorded. ResultsPart one: From 52 completed surveys, many cardiologists responded that measuring and supplementing taurine and recommending a diet change in cats with DCM are common practices. Few (15%) cardiologists reported an increase in the number of feline DCM cases over the past two years, although some had cases that improved even if taurine deficiency was not present. Part two: Twenty of 37 (54%) cats ate low pea/lentil (low PL) diets, and 14/37 (38%) ate high PL diets at the time of diagnosis; three had incomplete diet information. Two of 13 cats (15%) in which taurine was measured had levels below the reference range. After adjusting for other variables, cats eating high PL diets that changed diets after diagnosis had a significantly longer survival time than that of cats eating high PL diets that did not change diets after diagnosis (P = 0.025). ConclusionsAdditional research is warranted to determine whether there could be a possible association between diet and DCM in cats.

The Feline Cardiomyopathies: 3. Cardiomyopathies other than HCM

Practical relevance:Although feline hypertrophic cardiomyopathy (HCM) occurs more commonly, dilated cardiomyopathy (DCM), restrictive cardiomyopathy (RCM), arrhythmogenic right ventricular cardiomyopathy (ARVC), left ventricular noncompaction (LVNC) and cardiomyopathy – nonspecific phenotype (NCM; formerly unclassified cardiomyopathy) are all recognized in domestic cats.Patient group:Any adult domestic cat, of either sex and of any breed, can be affected.Diagnostics:The non-HCM cardiomyopathies are rarely suspected in subclinically affected cats, so most are first identified when a cat presents with signs of heart failure or systemic thromboembolic disease. The definitive clinical confirmatory test for these other feline cardiomyopathies is echocardiography.Key findings:‘Cardiomyopathy – nonspecific phenotype’ is a catch-all term that groups hearts with myocardial changes that either do not meet the criteria for any one type of cardiomyopathy (HCM, RCM, DCM, ARVC, LVNC) or meet the echocardiography criteria for more than one type. RCM is characterized by diastolic dysfunction due to fibrosis that results in a restrictive transmitral flow pattern on Doppler echocardiography and usually marked left or biatrial enlargement. DCM is characterized by decreased myocardial contractility and is rare in cats. When it occurs, it is seldom due to taurine deficiency. However, since taurine-deficient DCM is usually reversible, a diet history should be obtained, whole blood and plasma taurine levels should be measured and taurine should be supplemented in the diet if the diet is not commercially manufactured. ARVC should be suspected in adult cats with severe right heart enlargement and right heart failure (ascites and/or pleural effusion), especially if arrhythmia is present. Feline LVNC is rare; its significance continues to be explored. Treatment of the consequences of these cardiomyopathies (management of heart failure, thromboprophylaxis, treatment of systemic arterial thromboembolism) is the same as for HCM.Conclusions:While these other cardiomyopathies are less prevalent than HCM in cats, their clinical and radiographic presentation is often indistinguishable from HCM. Echocardiography is usually the only ante-mortem method to determine which type of cardiomyopathy is present. However, since treatment and prognosis are often similar for the feline cardiomyopathies, distinguishing among the cardiomyopathies is often not essential for determining appropriate therapy.Areas of uncertainty:The feline cardiomyopathies do not always fit into one distinct category. Interrelationships among cardiomyopathies in cats may exist and understanding these relationships in the future might provide critical insights regarding treatment and prognosis.

Dissociative anaesthesia in dogs and cats with use of tiletamine and zolazepam combination. What we already know about it.

This article is an attempt to gather available literature regarding the use of tiletamine and zolazepam combination in anaesthesia in dogs and cats. Although tiletamine and zolazepam mixture has been known in veterinary practice for a long time, the increased interest in these drugs has been observed only recently. Tiletamine, similarly to ketamine, is a drug which belongs to the phencyclidine group. Ketamine has considerable popularity in veterinary practice what suggests that other dissociative anaesthetic drugs, such as tiletamine, could also prove effective in cats' and dogs' anaesthetic care. Zolazepam is a widely used benzodiazepine known for its muscle relaxant and anticonvulsant properties. While conducting an electronic search for articles regarding the use of tiletamine-zolazepam combination in dogs and cats, it has been discovered that the literature on the subject (tiletamine-zolazepam combination in dogs and cats) is quite scarce. Very few articles were published after 2010. Databases used were: Google Scholar, Scopus, PubMed. Most of the adverse effects, including those affecting the cardiovascular, nervous, and respiratory systems, were strictly dose-dependent. Tiletamine-zolazepam combination can be safely used as a premedication agent, induction for inhalation anaesthesia, or an independent anaesthetic for short procedures. Contraindications using tiletamine-zolazepam mixture include central nervous system (CNS) diseases such as epilepsy and seizures, head trauma, penetrative eye trauma, cardiovascular abnormalities (hypertrophy cardiomyopathy in cats, arrythmias or conditions where increase of heart rate is inadvisable), hyperthyroidism, pancreatic deficiencies or kidney failure.

172 A genome wide association study of hypertrophic cardiomyopathy in cats

172 A genome wide association study of hypertrophic cardiomyopathy in cats

Novel biomarkers in cats with congestive heart failure due to primary cardiomyopathy

The pathogenesis of feline cardiomyopathy and congestive heart failure (CHF) requires further understanding. In this study, we assessed serum proteome change in feline CHF, aiming to identify novel biomarker for both research and clinical use. The study comprised 15 cats in CHF, 5 cats in preclinical cardiomyopathy and 15 cats as healthy controls. Serum proteome profiles were obtained by tandem mass tag labelling followed by mass spectrometry. Protein concentrations in CHF cats were compared with healthy controls. Western blot was performed for proteomic validation. Correlations were assessed between the altered proteins in CHF and clinical variables in cats with cardiomyopathy to evaluate protein-cardiac association. Bioinformatic analysis was employed to identify pathophysiological pathways involved in feline CHF. Sixteen serum proteins were significantly different between CHF and healthy control cats (P < .05). These included serine protease inhibitors, apolipoproteins and other proteins associated with inflammation and coagulation. Clinical parameters from cats with cardiomyopathy significantly correlated with the altered proteins (P < .05). Bioinformatic analysis identified 13 most relevant functional profiles in feline CHF, which mostly associated with extracellular matrix organization and metabolism.Data are available via ProteomeXchange with identifier PXD017761. SignificanceCardiomyopathies affect both cats and humans, and they can cause serious consequence such as congestive heart failure (CHF). To date, the pathophysiological mechanism of CHF is not fully understood. In this study, for the first time, we used a proteomic approach combined with bioinformatic analysis to evaluate serum protein change in cats with CHF. Results indicate systemic inflammation, coagulation protein changes, innate immunity and extracellular matrix remodeling are involved in feline CHF, which are largely comparable with findings in previous human studies. Our study provides new insights into CHF and cardiomyopathy in cats, and the identified novel biomarkers and pathophysiological pathways provide valuable information for future studies.

Vitamin D status in cats with cardiomyopathy.

BackgroundLow vitamin D concentrations have been associated with advanced heart disease and poorer outcomes in people and dogs. Vitamin D status typically is assessed by serum 25(OH)D concentration. However, cats also produce notable amounts of a C‐3 epimer of 25(OH)D (3‐epi).Hypothesis/ObjectivesDetermine if vitamin D status, estimated by 25(OH)D3 alone or combined with 3‐epi (summation vitD), is lower in cats with cardiomyopathy (CM) compared to clinically normal (N) cats and if indicators of disease severity are associated with vitamin D status.AnimalsPrivately owned cats, 44 with CM and 56 N.MethodsCross‐sectional observational study using clinical and echocardiographic findings, diet history, and serum 25(OH)D3 and 3‐epi measurements.ResultsCat age was negatively related to vitamin D status. Summation vitD was lower in CM cats (median = 47.1 ng/mL) compared to N cats (median = 58.65 ng/mL) both before (P = .03) and after (P = .04) accounting for age. However, 25(OH)D3 became nonsignificant between CM and N cats after age was included. Summation vitD was related positively to survival time and fractional shortening (FS), but negatively to left atrial enlargement (LAE) severity, both before and after accounting for age. For 25(OH)D3 alone, only survival time and FS remained significant after including age.Conclusions and Clinical ImportanceWe report 25(OH)D3 and 3‐epi concentrations in CM and N cats. Age had an important (negative) relationship to vitamin D status. After accounting for age, summation vitD was lower in CM cats. Vitamin D status was related positively to survival time and FS, but negatively to LAE severity.

Epidemiological and pathological aspects of cardiomyopathies in cats in southern Brazil

ABSTRACT: Cardiomyopathies are considered one of the most important causes of heart failure in cats and are subdivided into three main morphological types: hypertrophic (HCM), dilated (DCM), and restrictive (RCM). This study aimed to determine the frequency and types of cardiomyopathies in cats diagnosed in southern Brazil, with an emphasis on their epidemiological and pathological aspects. Necropsy reports filed in a veterinary pathology laboratory were reviewed, and cats diagnosed with cardiomyopathy were selected for the study. Animal identification data, history and clinical signs, and gross lesions, were reviewed and compiled. During the study period, 1.594 cat necropsies were performed, of which 72 (4.5%) comprised a diagnosis of cardiomyopathy. HCM was the most frequent followed by CMR and CMD, representing 77.8%, 12.5% and 9.7%, respectively. Age ranged from three months to 18 years, with a median age of seven years. In relation to sex, 62.5% were males and 37.5% females. In 76.4% of the cases, it affected cats without a breed defined. Restrictive mixed dyspnea and hydrothorax were the main signs or findings of the clinical examination. Sudden death and acute paresis of the pelvic limbs due to aortic thromboembolism have also been described. In HCM, myocardial thickening was observed, with a reduction in the ventricular chamber. Hypertrophy, disarray, and fibrosis of the myofibers were the main histological findings. In RCM, whitish and thickened endocardium was seen in most cases. DCM was characterized by dilated cardiac chambers, and microscopic examination revealed no significant findings. The main extra cardiac lesions revealed pulmonary edema and congestion, hydrothorax and chronic passive congestion of the liver. Cardiomyopathies are important causes of death in cats and should be included in the differential diagnosis of patients with cardio respiratory clinical signs and in cases related to sudden death and acute paresis of the pelvic limbs.

Cardiovascular-renal axis disorder and acute-phase proteins in cats with congestive heart failure caused by primary cardiomyopathy.

BackgroundCurrently, the pathogenesis of congestive heart failure (CHF) in cats is not fully understood.ObjectiveTo identify novel biomarkers for CHF in cats caused by primary cardiomyopathy, particularly related to cardiovascular‐renal axis disorder and systemic inflammatory response.AnimalsTwenty‐five cats in CHF caused by primary cardiomyopathy, 12 cats with preclinical cardiomyopathy, and 20 healthy controls.MethodsCase control and observational case series. The following serum biomarkers were compared among the 3 cat groups: a cardiorenal profile that included N‐terminal pro‐brain natriuretic peptide (NT‐proBNP), symmetric dimethylarginine (SDMA), and creatinine and an inflammatory profile that included 7 acute‐phase proteins (APPs). Survival analyses and longitudinal studies were performed in CHF cats.ResultsAll cardiorenal biomarkers were positively correlated and higher in CHF cats, and high NT‐proBNP and SDMA were associated with poor clinical outcome. Cats with CHF had significantly higher leucine‐rich alpha‐2‐glycoprotein 1, serum amyloid A, and ceruloplasmin, and these APPs were positively correlated with NT‐proBNP and left atrial size. In a multivariable survival analysis, alpha‐1‐acid glycoprotein concentration (P = .01), body weight (P = .02) and left atrial‐to‐aortic root ratio (P = .01) were independent prognostic factors for CHF in these cats.Conclusions and Clinical ImportanceIn cats, CHF is an inflammatory disorder and outcome in CHF may be determined by the extent of inflammation and possibly the amount of residual renal function. These novel biomarkers have potential use for the clinical management, prognosis, and future research into CHF and cardiomyopathy in cats.