Feline Cardiomyopathy and Thromboembolism

Winn funded research

Stokol, T., M. Brooks, et al. (2008). "Hypercoagulability in cats with cardiomyopathy." J Vet Intern Med 22(3): 546-552.

Arterial thromboembolism (ATE) is a serious and often fatal complication of cardiomyopathy in cats. Thromboemboli are believed to originate from clots in the left atrium or left atrial appendage. The factors causing clot formation are not fully understood. In this study, the researchers hypothesized that cats with cardiomyopathy develop ATE because they are in a systemic hypercoagulable state or have underlying endothelial (arterial or endocardial) injury. Healthy cats (n=30) and 3 groups of cats with cardiomyopathy were studied. Group 1 cats had left atrial enlargement (LAE) only. Group 2 cats had LAE with spontaneous echocardiographic contrast, atrial thrombi or both. Group 3 cats had acute ATE with LAE. Coagulation status was assessed in all three groups, including fibroginogen, Factor VIII, antithrombin, thrombin-antithrombin complex (TAT) and D-dimer concentrations. The 3 groups of cats with cardiac disease had higher median fibrinogen concentrations than did the healthy cats. Criteria of hypercoagulability were found exclusively in group 2 and group 3 cats. Hypercoagulability was not associated with left atrial size or congestive heart failure. Systemic hypercoagulability is evident in many cats with cardiomyopathy, often without concurrent congestive heart failure or overt ATE, and may represent a risk factor for ATE. The researchers concluded that the pathogenesis of ATE is multifactorial and therefore treatment and prevention of this syndrome might involve drug combinations modulating hemostasis and inflammatory pathways.

>> PubMed abstract

Related articles:

Bedard, C., A. Lanevschi-Pietersma, et al. (2007). "Evaluation of coagulation markers in the plasma of healthy cats and cats with asymptomatic hypertrophic cardiomyopathy." Vet Clin Pathol 36(2): 167-72.

>> PubMed abstract

Brazzell, J. L. and D. L. Borjesson (2007). "Evaluation of plasma antithrombin activity and D-dimer concentration in populations of healthy cats, clinically ill cats, and cats with cardiomyopathy." Vet Clin Pathol 36(1): 79-84.

>> PubMed abstract

More on cat health: Winn Feline Foundation Library

Winn funded research

Stokol, T., M. Brooks, et al. (2008). "Hypercoagulability in cats with cardiomyopathy." J Vet Intern Med 22(3): 546-552.

Arterial thromboembolism (ATE) is a serious and often fatal complication of cardiomyopathy in cats. Thromboemboli are believed to originate from clots in the left atrium or left atrial appendage. The factors causing clot formation are not fully understood. In this study, the researchers hypothesized that cats with cardiomyopathy develop ATE because they are in a systemic hypercoagulable state or have underlying endothelial (arterial or endocardial) injury. Healthy cats (n=30) and 3 groups of cats with cardiomyopathy were studied. Group 1 cats had left atrial enlargement (LAE) only. Group 2 cats had LAE with spontaneous echocardiographic contrast, atrial thrombi or both. Group 3 cats had acute ATE with LAE. Coagulation status was assessed in all three groups, including fibroginogen, Factor VIII, antithrombin, thrombin-antithrombin complex (TAT) and D-dimer concentrations. The 3 groups of cats with cardiac disease had higher median fibrinogen concentrations than did the healthy cats. Criteria of hypercoagulability were found exclusively in group 2 and group 3 cats. Hypercoagulability was not associated with left atrial size or congestive heart failure. Systemic hypercoagulability is evident in many cats with cardiomyopathy, often without concurrent congestive heart failure or overt ATE, and may represent a risk factor for ATE. The researchers concluded that the pathogenesis of ATE is multifactorial and therefore treatment and prevention of this syndrome might involve drug combinations modulating hemostasis and inflammatory pathways.

>> PubMed abstract

Related articles:

Bedard, C., A. Lanevschi-Pietersma, et al. (2007). "Evaluation of coagulation markers in the plasma of healthy cats and cats with asymptomatic hypertrophic cardiomyopathy." Vet Clin Pathol 36(2): 167-72.

>> PubMed abstract

Brazzell, J. L. and D. L. Borjesson (2007). "Evaluation of plasma antithrombin activity and D-dimer concentration in populations of healthy cats, clinically ill cats, and cats with cardiomyopathy." Vet Clin Pathol 36(1): 79-84.

>> PubMed abstract

More on cat health: Winn Feline Foundation Library

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Measurement of Heart Size in Cats

Ghadiri, A., R. Avizeh, et al. (2008). "Radiographic measurement of vertebral heart size in healthy stray cats." J Feline Med Surg 10(1): 61-5.

Determination of heart size on chest radiographs is important when evaluating cats for cardiac disease. An enlarged cardiac silhouette is an indicator of cardiac disease. However, determination of cardiac size is usually subjective. In recent years, a cardiac measurement technique called the vertebral heart size or score (VHS) has been investigated as a less biased assessment of cardiac size. VHS compares cardiac dimensions with the length of mid-thoracic vertebrae. It has previously been evaluated in mixed groups of obese and non-obese cats of various ages, breeds, and sizes. Different breeds of dogs may have different normal reference values for VHS but it is not known if there is variability in normal reference values for different populations of cats. The objective of this study was to determine VHS in clinically normal, domestic shorthair, non-obese stray cats. The study was performed in Ahvaz, Iran. Left and right lateral, dorsoventral and ventrodorsal radiographs were taken and evaluated. Absolute measurements and vertebral heart scale values were slightly smaller than those previously reported in the literature, indicating that normal reference values may vary by breed or population in cats.
>> PubMed abstract

Related articles:
Litster, A. and J. Buchanan (2000). "Vertebral scale system to measure heart size in radiographs of cats." J Amer Vet Med Assoc 216(2): 210-214.
>> PubMed abstract

More on cat health: Winn Feline Foundation Library

Ghadiri, A., R. Avizeh, et al. (2008). "Radiographic measurement of vertebral heart size in healthy stray cats." J Feline Med Surg 10(1): 61-5.

Determination of heart size on chest radiographs is important when evaluating cats for cardiac disease. An enlarged cardiac silhouette is an indicator of cardiac disease. However, determination of cardiac size is usually subjective. In recent years, a cardiac measurement technique called the vertebral heart size or score (VHS) has been investigated as a less biased assessment of cardiac size. VHS compares cardiac dimensions with the length of mid-thoracic vertebrae. It has previously been evaluated in mixed groups of obese and non-obese cats of various ages, breeds, and sizes. Different breeds of dogs may have different normal reference values for VHS but it is not known if there is variability in normal reference values for different populations of cats. The objective of this study was to determine VHS in clinically normal, domestic shorthair, non-obese stray cats. The study was performed in Ahvaz, Iran. Left and right lateral, dorsoventral and ventrodorsal radiographs were taken and evaluated. Absolute measurements and vertebral heart scale values were slightly smaller than those previously reported in the literature, indicating that normal reference values may vary by breed or population in cats.
>> PubMed abstract

Related articles:
Litster, A. and J. Buchanan (2000). "Vertebral scale system to measure heart size in radiographs of cats." J Amer Vet Med Assoc 216(2): 210-214.
>> PubMed abstract

More on cat health: Winn Feline Foundation Library

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Biochemical Markers for Feline Heart Disease

Connolly, D. J., R. J. Soares Magalhaes, et al. (2008). "Circulating natriuretic peptides in cats with heart disease." J Vet Intern Med 22(1): 96-105.with heart disease." J Vet Intern Med 22(1): 96-105.

Natriuretic peptides are hormones produced by cardiac muscle cells, and include atrial natriuretic peptide (ANP) and brain natriuretic peptide (BNP). These hormones are released in response to stretching of the atria (ANP) and ventricles (BNP), and are responsible for regulation of body fluids and blood pressure. The forms of these hormones measured in circulation are NT-proANP and NT-proBNP. In human medicine, these biochemical markers are used as patient-side tests for the diagnosis and prognosis of cardiac disease. In people with HCM, NT-proBNP is increased and correlates with severity of disease. Increased concentrations of BNP have been reported in cats with hypertrophic cardiomyopathy (HCM) and congestive heart failure (CHF). In this study, serum NT-proANP and NT-proBNP levels were measured in 28 healthy control cats and 50 cats with heart disease. Of the 50 cats with heart disease, 33 were in CHF while the remaining 17 were not. The study found that both markers were able to distinguish cats with heart disease from normal cats, but NT-proBNP was able to distinguish cats without CHF from normal cats. With further investigation, it may be possible to use NT-proBNP as a screening test for heart disease in cats. Any cats with positive test results should be evaluated with a more specific test, such as echocardiography, for false positives are possible.

>> PubMed abstract

Related articles:

MacLean, H. N., J. A. Abbott, et al. (2006). "N-terminal atrial natriuretic peptide immunoreactivity in plasma of cats with hypertrophic cardiomyopathy." J Vet Intern Med 20(2): 284-9.

>> PubMed abstract

Winn funded research

Biondo, A. W., E. J. Ehrhart, et al. (2003). "Immunohistochemistry of atrial and brain natriuretic peptides in control cats and cats with hypertrophic cardiomyopathy." Vet Pathol 40(5): 501-6.

>> PubMed abstract

More on cat health: Winn Feline Foundation Library

Connolly, D. J., R. J. Soares Magalhaes, et al. (2008). "Circulating natriuretic peptides in cats with heart disease." J Vet Intern Med 22(1): 96-105.with heart disease." J Vet Intern Med 22(1): 96-105.

Natriuretic peptides are hormones produced by cardiac muscle cells, and include atrial natriuretic peptide (ANP) and brain natriuretic peptide (BNP). These hormones are released in response to stretching of the atria (ANP) and ventricles (BNP), and are responsible for regulation of body fluids and blood pressure. The forms of these hormones measured in circulation are NT-proANP and NT-proBNP. In human medicine, these biochemical markers are used as patient-side tests for the diagnosis and prognosis of cardiac disease. In people with HCM, NT-proBNP is increased and correlates with severity of disease. Increased concentrations of BNP have been reported in cats with hypertrophic cardiomyopathy (HCM) and congestive heart failure (CHF). In this study, serum NT-proANP and NT-proBNP levels were measured in 28 healthy control cats and 50 cats with heart disease. Of the 50 cats with heart disease, 33 were in CHF while the remaining 17 were not. The study found that both markers were able to distinguish cats with heart disease from normal cats, but NT-proBNP was able to distinguish cats without CHF from normal cats. With further investigation, it may be possible to use NT-proBNP as a screening test for heart disease in cats. Any cats with positive test results should be evaluated with a more specific test, such as echocardiography, for false positives are possible.

>> PubMed abstract

Related articles:

MacLean, H. N., J. A. Abbott, et al. (2006). "N-terminal atrial natriuretic peptide immunoreactivity in plasma of cats with hypertrophic cardiomyopathy." J Vet Intern Med 20(2): 284-9.

>> PubMed abstract

Winn funded research

Biondo, A. W., E. J. Ehrhart, et al. (2003). "Immunohistochemistry of atrial and brain natriuretic peptides in control cats and cats with hypertrophic cardiomyopathy." Vet Pathol 40(5): 501-6.

>> PubMed abstract

More on cat health: Winn Feline Foundation Library

Read More