Introduction
The cardiac biomarkers are measurable biological indicators that play a crucial role in the detection, diagnosis and monitoring of heart disease in dogs and cats. They enable not only the diagnosis of asymptomatic pathologies, but also risk stratification and treatment adaptation for more precise management of heart disease. This article examines the use of biomarkers in routine veterinary practice, focusing on natriuretic peptides and troponins, which are widely used to assess the cardiac health of our animal patients.
Main cardiac biomarkers
The cardiac biomarkers most commonly used in veterinary medicine are :
Natriuretic peptides (BNP/NT-proBNP)
- These peptides are released in response to stress on cardiac myocyte walls, often due to volume overload or increased pressure. They include:
- BNP (B-type natriuretic peptide) and its precursor NT-proBNP (N-terminal proBNP).
- Physiological effects vasodilation, natriuresis, suppression of the renin-angiotensin-aldosterone (RAA) system, diuresis.
- Clinical indications Natriuretic peptides are particularly useful for diagnosing and differentiating congestive heart failure (CHF) from primary respiratory disease in dogs and cats presenting with clinical signs such as dyspnoea, tachypnoea or excessive fatigue.
Cardiac troponins (Troponin I and Troponin T)
- Troponins are markers of cellular damage myocardial proteins. These proteins are released into the circulation in response to direct damage to cardiac myocytes.
- Clinical indications Clinical indications: They are useful for detecting myocardial damage linked to various pathologies such as myocarditis, cardiomyopathies, or even non-cardiac conditions such as sepsis or gastric torsion.
Clinical Applications of Cardiac Biomarkers
Cardiac biomarkers have become valuable tools for risk stratification. risk stratificationrisk stratification treatment monitoring and detection of asymptomatic pathologies. Here are some of the most common clinical applications:
Diagnosis and Monitoring of Congestive Heart Failure (CHF)
- Visit BNP/NT-proBNP is commonly used to diagnose CHF in dogs and cats. These peptides help differentiate the cardiac origin of respiratory distress from that associated with primary respiratory pathology.
- In cats, an NT-proBNP level above 265 pmol/L is recommended to identify patients with CHF, although sensitivity is limited for mild to moderate cases.
Predicting and Monitoring the Evolution of Heart Disease
- The troponins are useful for assessing the degree of myocardial damage, particularly in cases of dilated cardiomyopathy (DCM) in Doberman Pinschers and other predisposed breeds.
- These markers help to monitor the progression of heart disease and adapt treatments to the evolution of myocardial damage.
Risk stratification
- The cardiac biomarkers can also be used to stratify patients according to the severity of their heart disease, enabling treatments and interventions to be prioritized.
Using Biomarkers to Differentiate Respiratory and Cardiac Pathologies
One of the main difficulties in managing dogs and cats suffering from acute respiratory distress is to differentiate between cardiac causes (such as CHF) and primary respiratory pathologies (such as bronchitis or asthma). Clinical signs, such as cough, tachypnea or respiratory effort, may be common to both types of pathology. Chest X-rays can sometimes be ambiguous. Blood tests based on biomarkers, in particular the NT-proBNPare useful for distinguishing pathologies of cardiac origin from those of respiratory origin. For example:
- Sensitivity and specificity A threshold of NT-proBNP threshold above 1,158 pmol/L showed a sensitivity of 85.5% and a specificity of 81.3% for differentiating CHF from primary respiratory disease in dogs.
Conclusion
The cardiac biomarkers tests play a crucial role in the diagnosis, monitoring and management of heart disease in dogs and cats. Veterinarians need to integrate these tests into their diagnostic arsenal to optimize the care and treatment of cardiac patients. Visit NT-proBNP and troponins are particularly useful for identifying the underlying causes of unspecific clinical signs, such as respiratory distress, and for assessing the severity of heart disease.
