Estimated reading time: 7 minute
Table of Contents
- Cardiac Biomarkers in Blood in MMVD
- Cardiac Biomarkers in Congestive Heart Failure (CHF)
- Cardiac Biomarkers in ARVC
- Dilated Cardiomyopathy (DCM) and Cardiac Biomarkers
- Meaning of NT-proBNP and cTnI Biomarkers
- Role of NT-proBNP in DCM Diagnosis
- Role of cTnI in Diagnosis of DCM
- Combined Use of NT-proBNP and cTnI
- NT-proBNP to Differentiate Between DCM and CHF
- Limitations of NT-proBNP and cTnI in Diagnosing DCM
Various laboratory tests (NT-PROBNP, T4, cTn-I, blood parasite test, biochemical parameters, complete blood count, etc.) may be required to master the changes in the body caused by the disease detected as a result of cardiology examination or to obtain values that can form a reference for treatment.
It should not be overlooked that some cardiological conditions may change as a result of some metabolic disorders, organ failures, endocrinal diseases, fluid-electrolyte imbalances, infections or parasitic diseases in the body.
Cardiac Biomarkers in Blood in MMVD
As the severity of Mitral Valve Disease (MMVD) increases, N-terminal pro-B type natriuretic peptide (NT-proBNP) ve cardiac troponin I (cTnI) Increased concentrations of cardiac biomarkers such as
Cardiac troponin I (cTnI), is a nonspecific marker of myocardial damageTherefore, an increase in this marker in the bloodstream can occur not only due to heart diseases but also due to different non-cardiac disease processes.
NT-proBNP if, is a marker released into the circulation in response to myocardial stretch and therefore is an indicator of cardiomegaly (enlargement of the heart).NT-proBNP measurement, effective in distinguishing between mild MMVD (stage B1) and moderate-severe MMVD (stage B2-D) It is shown.
In emergency situations, NT-proBNP, May be useful to distinguish increased respiratory rate and effort due to left-sided congestive heart failure (CHF) from increases caused by primary respiratory diseases. However, in dogs Coexistence of primary respiratory diseases with MMVD is possible and in this situation the additional diagnostic value of natriuretic peptides may be limited.
Other disadvantages of this method include: Lack of point-of-care tests ve There is a wide variation in NT-proBNP concentrations among races. .
Cardiac Biomarkers in Congestive Heart Failure (CHF)
Circulating cardiac biomarkers, especially N-terminal pro B-type natriuretic peptide (NT-proBNP) measuring the concentrations, the observed clinical findings to determine whether it is of cardiac origin might help.
Many studies have been conducted in dogs and cats, Patients with symptoms of congestive heart failure (CHF), such as dyspnea (shortness of breath), are more likely to have cardiac origins when circulating NT-proBNP levels are high. has revealed.
In addition, Measurement of NT-proBNP concentration in pleural fluid in cats with pleural effusion (fluid accumulation in the chest cavity), liquid to distinguish whether it is caused by a cardiac or non-cardiac cause It was found useful for. Low concentration of NT-proBNP in plasma or pleural fluidmakes the diagnosis of heart failure less likely.
The second reason to use the measurement of circulating cardiac troponin I (cTnI) concentration, especially in cats, Helps to differentiate heart failure causing dyspnea from other respiratory diseasesThis is important for rapid diagnosis and correct treatment selection.
Cardiac Biomarkers in ARVC
Circulating blood pressure in Boxer dogs with ARVC (Arrhythmogenic Right Ventricular Cardiomyopathy) cTnI (cardiac troponin I) concentrations may increase and May correlate with frequency of ventricular arrhythmia (VA)However, the distinction between dogs with ARVC and healthy Boxers using this marker is not always clear-cut, as there can be significant overlap between the two groups.
High sensitivity cTnI tests have the potential to increase diagnostic accuracy and further research is needed on this topic.
Whereas, Circulating BNP levels in Boxer dogs with ARVC does not increase significantly and therefore has a limited role in diagnosisThis may be because BNP is usually associated with heart enlargement (cardiomegaly) and left ventricular dysfunction, whereas the mechanisms in ARVC are different.
Dilated Cardiomyopathy (DCM) and Cardiac Biomarkers
Circulating cardiac biomarkers in the diagnosis of dilated cardiomyopathy (DCM) N-terminal pro-B type natriuretic peptide (NT-proBNP) ve cardiac troponin I (cTnI) are useful complementary tools. However, these markers cannot replace echocardiography or ECG. Although these biomarkers are not specific to DCM, they are stress, strain and myocardial injury are reflective indicators.
Meaning of NT-proBNP and cTnI Biomarkers
• NT-proBNP: In the heart muscle strain (exposure to stress) and increased end-diastolic pressure Therefore, elevated NT-proBNP levels are indicative of heart enlargement (cardiomegaly) and heart failure.
• cTnI: Indicates heart muscle damage (myocardial damage)Death or damage to myocardial cells causes this protein to be released into circulation.
The increase in both markers, May indicate presence or progression of DCM, but these markers are not specific to DCM. Echocardiography and ECG are required to definitively diagnose DCM.
Role of NT-proBNP in DCM Diagnosis
• Sensitivity = 70-80%
• Specificity = 90%
NT-proBNP is an important marker for detecting DCM at an early (preclinical) stage. In particular, can detect echocardiographic findings better than the arrhythmic form.
Because NT-proBNP is released in response to the stretching of the heart muscle walls, high circulating concentrations of this marker are useful in the early diagnosis of DCM. However, NT-proBNP may show daily and weekly changes. ve normal values may be higher in some races should not be forgotten. For example:
• Labrador Retriever ve Newfoundland The NT-proBNP reference values of dog breeds such as are higher than other breeds.
Therefore, use of breed-specific reference ranges is recommended.
Role of cTnI in Diagnosis of DCM
• Sensitivity = 81%
• Specificity = 73%
cTnI (cardiac troponin I), myocardial cell damage is one of the best indicators. When the heart muscle is damaged, cTnI is released from the cells and passes into the bloodstream.
Cut-off value = 0,113 ng/mL Respectively.
A cTnI concentration above this value may be suggestive of the presence of DCM. However, cTnI because of its lower specificity (increased not only in DCM but also in other heart muscle damage), not recommended as a sole diagnostic tool for DCM.
Combined Use of NT-proBNP and cTnI
The combined use of NT-proBNP and cTnI may increase diagnostic accuracy.
• While the sensitivity of NT-proBNP alone is 70-80%,
• cTnI has a sensitivity of 81%,
• Performing these two tests together, Provides higher accuracy in diagnosing DCM.
NT-proBNP assesses cardiac muscle strain, while cTnI assesses myocardial damage. Therefore, when data from both markers are combined, both mechanical stress as well as cellular damage evaluation is possible.
NT-proBNP to Differentiate Between DCM and CHF
As a result of DCM congestive heart failure (CHF) can develop.
Since NT-proBNP is associated with heart enlargement (cardiomegaly) and increased diastolic pressure, Useful for distinguishing between the presence of CHF and primary respiratory diseases.
• physical examination ve thorax x-ray In cases where we cannot definitively determine whether there is CHF, NT-proBNP can be an important guide.
• An elevated NT-proBNP indicates that CHF may be present.
• However, the value of this test, In cases where echocardiography cannot be performed more meaningful. If echocardiography is available, it is used for direct diagnosis.
Limitations of NT-proBNP and cTnI in Diagnosing DCM
1. Interracial Variation:
Normal values of NT-proBNP may vary among dog breeds. For example, Labrador Retriever ve Newfoundland The normal NT-proBNP concentration in dogs is higher than in other dogs. Therefore, a separate reference range should be used for each dog breed.
2. Daily and Weekly Fluctuation:
NT-proBNP concentrations may vary over time or even over weeks. These fluctuations may lead to misdiagnosis. Therefore, multiple measurements are recommended for diagnosis.
3. Necessity of Echocardiography:
NT-proBNP and cTnI may indicate the presence of DCM, but Echocardiography is required for definitive diagnosisThese biomarkers aid in diagnosis but do not directly prove the presence of DCM.
4. Effect of Additional Diseases:
cTnI, in all types of myocardial damage may increase. That is, myocardial damage other than DCM (e.g. myocarditis) may also increase the cTnI level. Therefore, for the diagnosis of DCM, cTnI alone should not be relied upon.
• NT-proBNP and cTnI do not replace echocardiography and ECG in the diagnosis of DCM, but provide complementary information.
• NT-proBNP, increases in response to heart wall stretch and early DCM detection using for.
• cTnIis indicative of myocardial damage and may indicate the presence of myocardial damage during DCM.
• Increasing sensitivity in diagnosing DCM Both biomarkers should be used together.
• In cases where echocardiography cannot be performed, NT-proBNP is useful for distinguishing between CHF and respiratory diseases.
The use of these biomarkers allows early diagnosis of DCM, early initiation of treatment, and monitoring of treatment effectiveness. An accurate diagnosis and early intervention can improve the patient's quality of life and prolong life.
Other Articles You May Be Interested In
“The first principle is that you must not fool yourself — the easiest person to fool is yourself.”
Richard Feynman
