Podcast
Questions and Answers
In echocardiography, which view is typically used to visualize the Four-Chamber view of the heart?
In echocardiography, which view is typically used to visualize the Four-Chamber view of the heart?
- Subcostal
- Right Parasternal Long Axis (correct)
- Left Apical
- Right Parasternal Short Axis
What does 'LVIDd' stand for in echocardiography measurements?
What does 'LVIDd' stand for in echocardiography measurements?
- Lateral Ventricular Internal Diameter during diastole
- Left Ventricular Isovolumic Dimension during diastole
- Left Ventricular Internal Diameter during diastole (correct)
- Left Ventricular Intramural Depth during diastole
The formula for Fractional Shortening (FS) in M-mode echocardiography is:
The formula for Fractional Shortening (FS) in M-mode echocardiography is:
- $(LVIDd + LVIDs) / LVIDd * 100$
- $(LVIDs - LVIDd) / LVIDs * 100$
- $(LVIDd - LVIDs) / LVIDs * 100$
- $(LVIDd - LVIDs) / LVIDd * 100$ (correct)
A normal Fractional Shortening (FS) in dogs, as assessed by M-mode echocardiography, is typically:
A normal Fractional Shortening (FS) in dogs, as assessed by M-mode echocardiography, is typically:
In the context of M-mode LV measurements, 'normalization' often involves dividing the measured value by a factor related to:
In the context of M-mode LV measurements, 'normalization' often involves dividing the measured value by a factor related to:
According to Cornell et al. (JVIM 2004), the formula for normalized LVIDd (LVIDdN) is:
According to Cornell et al. (JVIM 2004), the formula for normalized LVIDd (LVIDdN) is:
What is considered an abnormal LVIDdN value according to the JVIM 2004 paper?
What is considered an abnormal LVIDdN value according to the JVIM 2004 paper?
Ejection Fraction (EF) is a measure of:
Ejection Fraction (EF) is a measure of:
Simpson's method of discs is used in 2D echocardiography to calculate:
Simpson's method of discs is used in 2D echocardiography to calculate:
A normal Ejection Fraction (EF) in dogs, as assessed by 2D echocardiography, is typically:
A normal Ejection Fraction (EF) in dogs, as assessed by 2D echocardiography, is typically:
For 2D LV measurements normalization, Visser et al. (JVIM 2019) published which formula for LVIDdN?
For 2D LV measurements normalization, Visser et al. (JVIM 2019) published which formula for LVIDdN?
What is considered an abnormal LVIDdN value according to the JVIM 2019 paper by Visser et al.?
What is considered an abnormal LVIDdN value according to the JVIM 2019 paper by Visser et al.?
The LA-to-Ao ratio is measured in which echocardiographic view?
The LA-to-Ao ratio is measured in which echocardiographic view?
An LA-to-Ao ratio greater than 1.3 is considered:
An LA-to-Ao ratio greater than 1.3 is considered:
An LA-to-Ao ratio greater than 1.6 indicates:
An LA-to-Ao ratio greater than 1.6 indicates:
In dogs with Degenerative Mitral Valve Disease (DMVD), increased LA and LV measurements are clinically relevant because they can indicate:
In dogs with Degenerative Mitral Valve Disease (DMVD), increased LA and LV measurements are clinically relevant because they can indicate:
According to ACVIM consensus guidelines for DMVD, for asymptomatic dogs, an LVIDdN > 1.7 and LA:Ao > 1.6 are indications to:
According to ACVIM consensus guidelines for DMVD, for asymptomatic dogs, an LVIDdN > 1.7 and LA:Ao > 1.6 are indications to:
In systemic hypertension in dogs, echocardiography is used to assess:
In systemic hypertension in dogs, echocardiography is used to assess:
Which of the following is NOT a characteristic of the right heart compared to the left heart on a 2D echocardiogram?
Which of the following is NOT a characteristic of the right heart compared to the left heart on a 2D echocardiogram?
In cats with Hypertrophic Cardiomyopathy (HCM), which measurement is considered the most important index to guide therapy and prognosis?
In cats with Hypertrophic Cardiomyopathy (HCM), which measurement is considered the most important index to guide therapy and prognosis?
In cats, a normal Left Ventricular Internal Diameter in diastole (LVIDd) is typically in the range of:
In cats, a normal Left Ventricular Internal Diameter in diastole (LVIDd) is typically in the range of:
In Doppler echocardiography, blood flow follows two main principles:
In Doppler echocardiography, blood flow follows two main principles:
In mitral inflow profile assessment, the 'E wave' represents:
In mitral inflow profile assessment, the 'E wave' represents:
High Left Atrial Pressure (LAP) is often described as the 'end-product' of:
High Left Atrial Pressure (LAP) is often described as the 'end-product' of:
A normal E wave velocity in mitral inflow profile is typically:
A normal E wave velocity in mitral inflow profile is typically:
In ventricular outflow assessment using Doppler, a velocity greater than 2 m/s in the aortic outflow profile may indicate:
In ventricular outflow assessment using Doppler, a velocity greater than 2 m/s in the aortic outflow profile may indicate:
Medical ultrasound (including Doppler) directly measures:
Medical ultrasound (including Doppler) directly measures:
The simplified Bernoulli's equation used in echocardiography to estimate pressure gradient (P) is:
The simplified Bernoulli's equation used in echocardiography to estimate pressure gradient (P) is:
In the simplified Bernoulli's equation (P = 4V), 'V' represents:
In the simplified Bernoulli's equation (P = 4V), 'V' represents:
In SI units, the factor of '4' in the simplified Bernoulli's equation (P = 4V) approximates:
In SI units, the factor of '4' in the simplified Bernoulli's equation (P = 4V) approximates:
According to the table of normal intracardiac pressures, what is the normal systolic pressure in the right ventricle (RV) in small animals?
According to the table of normal intracardiac pressures, what is the normal systolic pressure in the right ventricle (RV) in small animals?
What is the normal diastolic pressure in the aorta in small animals?
What is the normal diastolic pressure in the aorta in small animals?
In a case of severe pulmonary stenosis with a Doppler velocity of 5 m/s across the pulmonic valve, what is the estimated pressure gradient (PG) using the simplified Bernoulli's equation?
In a case of severe pulmonary stenosis with a Doppler velocity of 5 m/s across the pulmonic valve, what is the estimated pressure gradient (PG) using the simplified Bernoulli's equation?
If the estimated pressure gradient (PG) across the pulmonic valve is 100 mmHg and the right atrial pressure is assumed to be 20 mmHg, what is the estimated Right Ventricular Systolic Pressure (RVSP)?
If the estimated pressure gradient (PG) across the pulmonic valve is 100 mmHg and the right atrial pressure is assumed to be 20 mmHg, what is the estimated Right Ventricular Systolic Pressure (RVSP)?
In a case of pulmonary hypertension with a tricuspid regurgitation velocity of 5 m/s, what is the estimated pressure gradient (PG) using the simplified Bernoulli's equation?
In a case of pulmonary hypertension with a tricuspid regurgitation velocity of 5 m/s, what is the estimated pressure gradient (PG) using the simplified Bernoulli's equation?
If the estimated pressure gradient from tricuspid regurgitation is 100 mmHg and the right atrial pressure is assumed to be 5 mmHg, what is the estimated Pulmonary Artery Systolic Pressure (PASP)?
If the estimated pressure gradient from tricuspid regurgitation is 100 mmHg and the right atrial pressure is assumed to be 5 mmHg, what is the estimated Pulmonary Artery Systolic Pressure (PASP)?
Which statement is true regarding Doppler echocardiography?
Which statement is true regarding Doppler echocardiography?
When using Doppler echocardiography in clinical practice, it is crucial to:
When using Doppler echocardiography in clinical practice, it is crucial to:
Which of the following best describes the 'Continuity of Flow' principle in hemodynamics?
Which of the following best describes the 'Continuity of Flow' principle in hemodynamics?
In the context of the Extended Bernoulli's equation, the term $\int_{1}^{2} \frac{2 \bar{v}}{dt} \times d\bar{s}$ represents:
In the context of the Extended Bernoulli's equation, the term $\int_{1}^{2} \frac{2 \bar{v}}{dt} \times d\bar{s}$ represents:
Why is the simplified Bernoulli equation (P = 4V) considered sufficient for clinical echocardiography in cases of stenosis, valve regurgitation, or shunts?
Why is the simplified Bernoulli equation (P = 4V) considered sufficient for clinical echocardiography in cases of stenosis, valve regurgitation, or shunts?
In echocardiography, which view is most appropriate for assessing the LA-to-Ao ratio?
In echocardiography, which view is most appropriate for assessing the LA-to-Ao ratio?
According to Cornell et al. (JVIM 2004), what is the threshold LVIDdN value above which the measurement is considered abnormal?
According to Cornell et al. (JVIM 2004), what is the threshold LVIDdN value above which the measurement is considered abnormal?
What is meant by 'normalization' of M-mode LV measurements, such as LVIDd?
What is meant by 'normalization' of M-mode LV measurements, such as LVIDd?
What does the 'E wave' represent in mitral inflow profile assessment using Doppler echocardiography?
What does the 'E wave' represent in mitral inflow profile assessment using Doppler echocardiography?
If a dog has a tricuspid regurgitation velocity of 4 m/s, what is the estimated pressure gradient (PG) using the simplified Bernoulli equation?
If a dog has a tricuspid regurgitation velocity of 4 m/s, what is the estimated pressure gradient (PG) using the simplified Bernoulli equation?
In cats with hypertrophic cardiomyopathy (HCM), which measurement or assessment is considered the most important index to guide therapy and prognosis?
In cats with hypertrophic cardiomyopathy (HCM), which measurement or assessment is considered the most important index to guide therapy and prognosis?
What is the underlying principle behind using Doppler echocardiography to estimate pressure gradients across a stenotic valve?
What is the underlying principle behind using Doppler echocardiography to estimate pressure gradients across a stenotic valve?
In the context of the extended Bernoulli equation, what does the term $\int_{1}^{2} \frac{2 \bar{v}}{dt} \times d\bar{s}$ account for that is ignored in the simplified equation?
In the context of the extended Bernoulli equation, what does the term $\int_{1}^{2} \frac{2 \bar{v}}{dt} \times d\bar{s}$ account for that is ignored in the simplified equation?
Which of the following best explains why measurements in echocardiography for cats are typically not normalized?
Which of the following best explains why measurements in echocardiography for cats are typically not normalized?
Consider a scenario where a dog presents with clinical signs suggestive of both mitral regurgitation and pulmonary hypertension. Tricuspid regurgitation velocity is measured at 4.5 m/s, and right atrial pressure is estimated at 8 mmHg. Given these findings, what is the estimated pulmonary artery systolic pressure (PASP), considering the potential impact of mitral regurgitation on pulmonary pressures?
Consider a scenario where a dog presents with clinical signs suggestive of both mitral regurgitation and pulmonary hypertension. Tricuspid regurgitation velocity is measured at 4.5 m/s, and right atrial pressure is estimated at 8 mmHg. Given these findings, what is the estimated pulmonary artery systolic pressure (PASP), considering the potential impact of mitral regurgitation on pulmonary pressures?
In right parasternal long axis views of the heart, which chamber is typically located at the top of the four-chamber view?
In right parasternal long axis views of the heart, which chamber is typically located at the top of the four-chamber view?
Which view allows visualization of the aorta in addition to the standard four chambers of the heart?
Which view allows visualization of the aorta in addition to the standard four chambers of the heart?
In the right parasternal short axis view at the heart base, which structure is often referred to as the 'Mercedes' or 'Mercedes-Benz sign'?
In the right parasternal short axis view at the heart base, which structure is often referred to as the 'Mercedes' or 'Mercedes-Benz sign'?
When measuring the LA-to-Ao ratio, at what point in the cardiac cycle should the measurements be taken?
When measuring the LA-to-Ao ratio, at what point in the cardiac cycle should the measurements be taken?
What does Fractional Shortening (FS) assess?
What does Fractional Shortening (FS) assess?
What is the primary reason for normalizing left ventricular measurements in echocardiography?
What is the primary reason for normalizing left ventricular measurements in echocardiography?
What is the Simpson's method of disks used for in echocardiography?
What is the Simpson's method of disks used for in echocardiography?
According to the information provided, when is an ejection fraction considered normal in dogs?
According to the information provided, when is an ejection fraction considered normal in dogs?
In the context of degenerative mitral valve disease (DMVD) in dogs, what does the presence of increased LA and LV dimensions typically indicate?
In the context of degenerative mitral valve disease (DMVD) in dogs, what does the presence of increased LA and LV dimensions typically indicate?
According to the information provided, what is the key measurement used to guide therapy and assess prognosis in cats with hypertrophic cardiomyopathy (HCM)?
According to the information provided, what is the key measurement used to guide therapy and assess prognosis in cats with hypertrophic cardiomyopathy (HCM)?
According to the information provided, blood flow follows two main principles. Which of the following dictates how fast blood flows:
According to the information provided, blood flow follows two main principles. Which of the following dictates how fast blood flows:
In the context of the Frank-Starling principle, how does an increased left ventricular diastolic dimension affect the subsequent contraction?
In the context of the Frank-Starling principle, how does an increased left ventricular diastolic dimension affect the subsequent contraction?
What can cause a falsely normal fractional shortening or ejection fraction?
What can cause a falsely normal fractional shortening or ejection fraction?
How does persistent systemic hypertension affect the left ventricle?
How does persistent systemic hypertension affect the left ventricle?
In general, how does the size and wall thickness of the normal right heart compare to the left heart on a 2D echocardiogram?
In general, how does the size and wall thickness of the normal right heart compare to the left heart on a 2D echocardiogram?
According to the information provided, what is the diagnostic criterion for hypertrophic cardiomyopathy (HCM) in cats, based on left ventricular wall thickness?
According to the information provided, what is the diagnostic criterion for hypertrophic cardiomyopathy (HCM) in cats, based on left ventricular wall thickness?
What determines the height/velocity of the 'E wave' in mitral inflow profile?
What determines the height/velocity of the 'E wave' in mitral inflow profile?
According to the information provided, medical ultrasound directly measures:
According to the information provided, medical ultrasound directly measures:
According to the information provided, what is the simplified Bernoulli equation?
According to the information provided, what is the simplified Bernoulli equation?
In the simplified Bernoulli equation, what does 'V' represent?
In the simplified Bernoulli equation, what does 'V' represent?
According to the information provided, the simplified Bernoulli equation is derived from what principle?
According to the information provided, the simplified Bernoulli equation is derived from what principle?
Why doesn't the simplified Bernoulli equation account for the V1 (initial) velocity?
Why doesn't the simplified Bernoulli equation account for the V1 (initial) velocity?
A six-month-old French Bulldog puppy is diagnosed with congenital pulmonic stenosis. The maximum velocity across the stenotic pulmonic valve is measured at 4.0 m/s. Using the simplified Bernoulli equation, what is the estimated pressure gradient across the valve?
A six-month-old French Bulldog puppy is diagnosed with congenital pulmonic stenosis. The maximum velocity across the stenotic pulmonic valve is measured at 4.0 m/s. Using the simplified Bernoulli equation, what is the estimated pressure gradient across the valve?
After calculating a pressure gradient of 64 mmHg across the stenotic pulmonic valve in the previous question, and assuming a normal right atrial pressure of 5 mmHg, what is the estimated right ventricular systolic pressure (RVSP)?
After calculating a pressure gradient of 64 mmHg across the stenotic pulmonic valve in the previous question, and assuming a normal right atrial pressure of 5 mmHg, what is the estimated right ventricular systolic pressure (RVSP)?
A 7-year-old Pit Bull presents with syncope and is diagnosed with pulmonary hypertension. Tricuspid regurgitation is detected, with a velocity of 4.5 m/s. Estimate the pressure gradient across the tricuspid valve using the simplified Bernoulli equation.
A 7-year-old Pit Bull presents with syncope and is diagnosed with pulmonary hypertension. Tricuspid regurgitation is detected, with a velocity of 4.5 m/s. Estimate the pressure gradient across the tricuspid valve using the simplified Bernoulli equation.
Given a pressure gradient of 81 mmHg across the tricuspid valve (estimated from the previous question) and assuming a right atrial pressure of 5 mmHg, estimate the pulmonary artery systolic pressure (PASP).
Given a pressure gradient of 81 mmHg across the tricuspid valve (estimated from the previous question) and assuming a right atrial pressure of 5 mmHg, estimate the pulmonary artery systolic pressure (PASP).
What is the primary limitation of using Doppler echocardiography to assess cardiac function and hemodynamics?
What is the primary limitation of using Doppler echocardiography to assess cardiac function and hemodynamics?
Why is the right heart challenging to assess with echocardiography, compared to the left heart?
Why is the right heart challenging to assess with echocardiography, compared to the left heart?
When there is no obstruction between the right ventricle and pulmonary artery, the RV systolic pressure should be equivalent to:
When there is no obstruction between the right ventricle and pulmonary artery, the RV systolic pressure should be equivalent to:
If you're seeing normal ranges when measuring for fractional shortening, but the diastolic dimension is high/dilated, and the systolic dimension did not come down to normal, should you consider the function to be normal?
If you're seeing normal ranges when measuring for fractional shortening, but the diastolic dimension is high/dilated, and the systolic dimension did not come down to normal, should you consider the function to be normal?
In a patient, if you suspect right heart disease, you can look for abnormalities based on certain indications based on what is "usually" seen in 2D. Which assessment is correct?
In a patient, if you suspect right heart disease, you can look for abnormalities based on certain indications based on what is "usually" seen in 2D. Which assessment is correct?
What can be said of systolic function?
What can be said of systolic function?
A seven-year-old pit bull presented for syncope. You diagnose based on your echocardiographic findings to be pulmonary hypertension with tricuspid regurgitation. A drug is then prescribed that causes systemic vascular resistance vasodilation. What will be the net effect?
A seven-year-old pit bull presented for syncope. You diagnose based on your echocardiographic findings to be pulmonary hypertension with tricuspid regurgitation. A drug is then prescribed that causes systemic vascular resistance vasodilation. What will be the net effect?
In reference to the AI illustration of the heart doing a bench press, if the heart muscle is healthy but has too much weight on the bar, what will you see. And does that mean the contractility is unhealthy/abnormal?
In reference to the AI illustration of the heart doing a bench press, if the heart muscle is healthy but has too much weight on the bar, what will you see. And does that mean the contractility is unhealthy/abnormal?
A Doberman presents to your clinic and is diagnosed with dilated cardiomyopathy (DCM). You perform an echocardiogram and determine that the left ventricular systolic dimension (LVIDs) is significantly elevated, despite a normal left ventricular diastolic dimension (LVIDd). Fractional shortening (FS) is calculated to be within the normal range. What is the most likely explanation for these findings?
A Doberman presents to your clinic and is diagnosed with dilated cardiomyopathy (DCM). You perform an echocardiogram and determine that the left ventricular systolic dimension (LVIDs) is significantly elevated, despite a normal left ventricular diastolic dimension (LVIDd). Fractional shortening (FS) is calculated to be within the normal range. What is the most likely explanation for these findings?
A Great Dane presents with an LA:Ao of 1.4. Is this normal or abnormal.
A Great Dane presents with an LA:Ao of 1.4. Is this normal or abnormal.
A dog presents with severe mitral regurgitation. You take an echocardiogram and notice the mitral valve appears thickened and doesn't close completely during systole. What visible characteristic in color Doppler would confirm mitral regurgitation?
A dog presents with severe mitral regurgitation. You take an echocardiogram and notice the mitral valve appears thickened and doesn't close completely during systole. What visible characteristic in color Doppler would confirm mitral regurgitation?
According to the information provided, the end product of any left-sided heart disease is:
According to the information provided, the end product of any left-sided heart disease is:
An echocardiogram indicates elevated aortic outflow/velocity. According to the lecture, what COULD that indicate?
An echocardiogram indicates elevated aortic outflow/velocity. According to the lecture, what COULD that indicate?
In right parasternal long axis views, which chamber is located most cranially in the four-chamber view?
In right parasternal long axis views, which chamber is located most cranially in the four-chamber view?
Which echocardiographic view is characterized by the 'Mercedes-Benz sign'?
Which echocardiographic view is characterized by the 'Mercedes-Benz sign'?
When should the LA-to-Ao ratio be measured?
When should the LA-to-Ao ratio be measured?
What does Fractional Shortening (FS) primarily assess?
What does Fractional Shortening (FS) primarily assess?
What is the main reason for creating 'normalized' left ventricular measurements?
What is the main reason for creating 'normalized' left ventricular measurements?
What information does the E wave provide in mitral inflow profile assessment?
What information does the E wave provide in mitral inflow profile assessment?
In the context of M-mode echocardiography, what does LVIDd represent?
In the context of M-mode echocardiography, what does LVIDd represent?
Which of the following best describes the right heart's characteristics, compared to the left heart, in a normal 2D echocardiogram?
Which of the following best describes the right heart's characteristics, compared to the left heart, in a normal 2D echocardiogram?
An LA-to-Ao ratio greater than 1.6 in dogs typically indicates:
An LA-to-Ao ratio greater than 1.6 in dogs typically indicates:
In a dog with degenerative mitral valve disease (DMVD), increased LA and LV dimensions are most clinically relevant for indicating:
In a dog with degenerative mitral valve disease (DMVD), increased LA and LV dimensions are most clinically relevant for indicating:
In Doppler echocardiography, what information does the driving pressure provide concerning the blood flow?
In Doppler echocardiography, what information does the driving pressure provide concerning the blood flow?
What does an elevated aortic outflow velocity, as assessed by Doppler echocardiography, typically indicate?
What does an elevated aortic outflow velocity, as assessed by Doppler echocardiography, typically indicate?
What is the normal systolic pressure of the right ventricle in small animals?
What is the normal systolic pressure of the right ventricle in small animals?
Why is accurate Doppler technique essential?
Why is accurate Doppler technique essential?
What potential effect can persistent systemic hypertension have on the left ventricle?
What potential effect can persistent systemic hypertension have on the left ventricle?
Which of the following is most likely when systolic dimension does not reach normal dimensions with a high/dilated diastolic dimension?
Which of the following is most likely when systolic dimension does not reach normal dimensions with a high/dilated diastolic dimension?
Why is assessing the right heart with echocardiography often more challenging compared to assessing the left heart?
Why is assessing the right heart with echocardiography often more challenging compared to assessing the left heart?
Which of the following is true regarding the assessment of pressure and blood flow? (Select the best answer)
Which of the following is true regarding the assessment of pressure and blood flow? (Select the best answer)
How might severe mitral regurgitation influence left ventricular systolic performance as assessed by fractional shortening (FS)?
How might severe mitral regurgitation influence left ventricular systolic performance as assessed by fractional shortening (FS)?
What is one reason the right heart can be difficult to assess?
What is one reason the right heart can be difficult to assess?
How does a drug that causes systemic vascular resistance vasodilation during treatment for pulmonary hypertension with tricuspid regurgitation affect the heart?
How does a drug that causes systemic vascular resistance vasodilation during treatment for pulmonary hypertension with tricuspid regurgitation affect the heart?
An echocardiogram technician tells you normalization isn't typically done for feline measurements. Which option is the most likely reason for this?
An echocardiogram technician tells you normalization isn't typically done for feline measurements. Which option is the most likely reason for this?
When the right ventricle and pulmonary artery path is wide open, the RV systolic pressure should be:
When the right ventricle and pulmonary artery path is wide open, the RV systolic pressure should be:
What is the significance of left atrial pressure (LAP) in the context of heart disease?
What is the significance of left atrial pressure (LAP) in the context of heart disease?
What is the key consideration when employing the simplified Bernoulli equation ($P = 4V^2$) in clinical echocardiography?
What is the key consideration when employing the simplified Bernoulli equation ($P = 4V^2$) in clinical echocardiography?
Under what circumstance might a fractional shortening measurement lead to a misleading conclusion about systolic function?
Under what circumstance might a fractional shortening measurement lead to a misleading conclusion about systolic function?
What is the most likely reason fractional shortening or ejection fraction might appear normal, despite the heart NOT performing normally?
What is the most likely reason fractional shortening or ejection fraction might appear normal, despite the heart NOT performing normally?
If the heart muscle is healthy but you're seeing struggling on your imaging, what is true of the contractility?
If the heart muscle is healthy but you're seeing struggling on your imaging, what is true of the contractility?
In advanced imaging, the heart is illustrated on a bench press struggling. Which of the following defines 'systolic function'?
In advanced imaging, the heart is illustrated on a bench press struggling. Which of the following defines 'systolic function'?
Which best describes the 'path of least resistance' principle in the context of blood flow dynamics?
Which best describes the 'path of least resistance' principle in the context of blood flow dynamics?
What does the speaker describe as, 'more than 50% of the time what cardiologists do.'?
What does the speaker describe as, 'more than 50% of the time what cardiologists do.'?
What does the speaker say is a common critique of the normalization process described by Cornell et al. (JVIM 2004)
What does the speaker say is a common critique of the normalization process described by Cornell et al. (JVIM 2004)
In right parasternal long axis views of the heart, which chamber is typically located most cranially in the four-chamber view?
In right parasternal long axis views of the heart, which chamber is typically located most cranially in the four-chamber view?
Which echocardiographic view is characterized by the 'Mercedes-Benz sign', representing the aortic valve cusps?
Which echocardiographic view is characterized by the 'Mercedes-Benz sign', representing the aortic valve cusps?
When should the LA-to-Ao ratio be measured in the cardiac cycle to ensure consistency and accuracy?
When should the LA-to-Ao ratio be measured in the cardiac cycle to ensure consistency and accuracy?
What does Fractional Shortening (FS) primarily assess in M-mode echocardiography?
What does Fractional Shortening (FS) primarily assess in M-mode echocardiography?
What is the main reason for creating 'normalized' left ventricular measurements in echocardiography?
What is the main reason for creating 'normalized' left ventricular measurements in echocardiography?
What information does the E wave provide in mitral inflow profile assessment using Doppler echocardiography?
What information does the E wave provide in mitral inflow profile assessment using Doppler echocardiography?
According to the provided lecture, what is the normal systolic pressure of the right ventricle in small animals?
According to the provided lecture, what is the normal systolic pressure of the right ventricle in small animals?
Why is accurate Doppler technique essential for reliable echocardiographic assessments?
Why is accurate Doppler technique essential for reliable echocardiographic assessments?
What potential effect can persistent systemic hypertension have on the left ventricle, as visualized on echocardiogram?
What potential effect can persistent systemic hypertension have on the left ventricle, as visualized on echocardiogram?
Which of the following is most likely when systolic dimension does not reach normal dimensions with a high/dilated diastolic dimension, despite a seemingly normal fractional shortening?
Which of the following is most likely when systolic dimension does not reach normal dimensions with a high/dilated diastolic dimension, despite a seemingly normal fractional shortening?
Which of the following is true regarding the assessment of pressure and blood flow in echocardiography? (Select the best answer)
Which of the following is true regarding the assessment of pressure and blood flow in echocardiography? (Select the best answer)
Consider a scenario where a dog presents with clinical signs suggestive of both mitral regurgitation and pulmonary hypertension. Tricuspid regurgitation velocity is measured at 4.5 m/s, and right atrial pressure is estimated at 8 mmHg. Given these findings, what is the estimated pulmonary artery systolic pressure (PASP)?
Consider a scenario where a dog presents with clinical signs suggestive of both mitral regurgitation and pulmonary hypertension. Tricuspid regurgitation velocity is measured at 4.5 m/s, and right atrial pressure is estimated at 8 mmHg. Given these findings, what is the estimated pulmonary artery systolic pressure (PASP)?
Flashcards
M-mode LV measurement
M-mode LV measurement
A method to measure left ventricular size.
Allometric Scaling
Allometric Scaling
Used normalize LV measurements; accounts for body size differences.
2D LV measurement
2D LV measurement
A 2D measure of the LV.
Ejection Fraction
Ejection Fraction
Signup and view all the flashcards
LA-to-Ao Ratio
LA-to-Ao Ratio
Signup and view all the flashcards
DMVD
DMVD
Signup and view all the flashcards
Right Heart Assessment
Right Heart Assessment
Signup and view all the flashcards
HCM in cats
HCM in cats
Signup and view all the flashcards
Doppler Echocardiography
Doppler Echocardiography
Signup and view all the flashcards
Mitral Valve Opening
Mitral Valve Opening
Signup and view all the flashcards
Ventricular Outflow
Ventricular Outflow
Signup and view all the flashcards
Doppler Limitations
Doppler Limitations
Signup and view all the flashcards
Continuity of Flow
Continuity of Flow
Signup and view all the flashcards
Bernoulli's Principle
Bernoulli's Principle
Signup and view all the flashcards
Bernoulli's equation
Bernoulli's equation
Signup and view all the flashcards
Solving PGs
Solving PGs
Signup and view all the flashcards
Simplified Bernoulli Equation
Simplified Bernoulli Equation
Signup and view all the flashcards
Doppler caution
Doppler caution
Signup and view all the flashcards
What is the left ventricle?
What is the left ventricle?
Signup and view all the flashcards
What is the right ventricle?
What is the right ventricle?
Signup and view all the flashcards
What is fractional shortening?
What is fractional shortening?
Signup and view all the flashcards
What is normal ejection fraction?
What is normal ejection fraction?
Signup and view all the flashcards
What is Simpson's method of disks?
What is Simpson's method of disks?
Signup and view all the flashcards
What is systemic hypertension?
What is systemic hypertension?
Signup and view all the flashcards
What is Frank-Starling principle?
What is Frank-Starling principle?
Signup and view all the flashcards
What is contractility?
What is contractility?
Signup and view all the flashcards
What is systolic function?
What is systolic function?
Signup and view all the flashcards
What is pulmonary valve stenosis?
What is pulmonary valve stenosis?
Signup and view all the flashcards
What is pulmonary hypertension?
What is pulmonary hypertension?
Signup and view all the flashcards
What is tricuspid regurgitation?
What is tricuspid regurgitation?
Signup and view all the flashcards
Study Notes
- The lecture focuses on interpreting echocardiogram measurements and introduces advanced concepts.
Review of Echocardiography Views
- Right Parasternal Long Axis views include the four-chamber and five-chamber (outflow) view.
- Key anatomical structures in these views: right ventricle, right atrium, tricuspid valve, left ventricle, left atrium, mitral valve, interventricular septum, interatrial septum, and aorta with the aortic valve.
- Right Parasternal Short Axis views show the left ventricle with papillary muscles and the mitral valve.
- Key anatomical structures: left ventricle, right ventricle, interventricular septum, papillary muscles, and mitral valve ("fish mouth").
- Heart base views visualize the left atrium and pulmonary artery.
- Key anatomical structures: aortic valve (Mercedes-Benz sign), left atrium (whale), right atrium, right ventricle, tricuspid valve, internatural septum, pulmonary trunk/artery, pulmonary valve, and pulmonary arteries.
- Left Apical views include the five-chamber and four-chamber views.
- Key anatomical structures: left ventricle, left atrium, aorta, mitral valve, aortic valve, right ventricle, right atrium, and tricuspid valve.
2D and M-Mode Measurements of the Left Ventricle (LV)
- M-mode measurements visualize LV contraction, allowing measurement of diastolic (LVIDd) and systolic (LVIDs) dimensions.
- LVIDd indicates LV size; elevated in dilation, reduced in dehydration.
- Systolic dimension (LVIDs) reflects LV function.
- Fractional Shortening (FS) measures the percentage of LV contraction: FS (%) = (LVIDd - LVIDs) / LVIDd x 100; normal is around 30% or greater.
- Significantly low FS (e.g., 10-15%) indicates abnormality.
Normalization of LV Measurements
- Normalization adjusts measurements for body size differences between animals (e.g., Chihuahua vs. Irish Wolfhound).
- Cornell normalization is considered too forgiving.
- Breed-specific references are preferred when available.
- Formulas for Allometric Scaling (Cornell et al., JVIM 2004):
- LVIDdN = LVIDd ÷ BW^0.294
- LVIDsN = LVIDs ÷ BW^0.315
- Abnormal values in the paper: LVIDdN > 1.85, LVIDsN > 1.26.
- Cut-off values depend on the clinical context.
2D LV Measurements: Volumetric
- 2D measurements allow for direct measurement of LV dimensions without M-mode.
- Simpson's method of discs estimates LV volume. The machine assumes geometric, splits volume into many little discs, calculates it, and sums for a calculated 3D volume.
- Ejection Fraction (EF) assesses volumetric function: EF (%) = (LVVd -LVVS)/LVVd x 100; normal is 45-50% and above.
- EF is a key parameter for categorizing heart disease and heart failure.
Normalization of Volumetric Measurements
- Equations are used to normalize measurements.
- Formulas were published by Visser et al. (JVIM 2019):
- LVIDdN = LVIDd ÷ BW^0.316
- LVIDSN = LVIDs ÷ BW^0.392
- Abnormal values: LVIDdN > 1.61 and LVIDSN > 0.93
- If there are breed-specific measurements, use those over standard equations.
Interpretation Considerations for LV Systolic Function
- Systolic dimension should always be within the normal range, regardless of diastolic dimension.
- Fractional shortening (FS) or ejection fraction (EF) can be falsely normal, low, or high based on diastolic dimension
- Frank-Starling Principle: increased myocardial stretch (higher LVIDd) leads to more pronounced contraction.
- High LVIDd + high LVIDs = Normal FS/EF with reduced function
- Small LVIDd + higher normal LVIDs = Low FS/EF with normal function
- Systolic function (imaging parameter) and contractility (cellular/tissue level) are different concepts.
- Systolic function is the end result of loading conditions (preload, afterload).
- Contractility is inherent to the muscle cells, independent of loading conditions.
Left Atrium (LA) Measurements: LA-to-Aorta (Ao) Ratio
- Ao size is used as an internal scaling component for LA size.
- Measured on Right Parasternal Short Axis (RPSAX) at the heart base (whale view) at end-systole (AV closure).
- Measurement involves identifying the non-coronary and left coronary cusps of the aortic valve.
- Draw a line across the closure line (bisecting the aortic valve) to measure the Ao diameter.
- Draw a line along the same line to measure the LA dimension.
- LA:Ao > 1.3 is abnormal.
- LA:Ao > 1.6 indicates significant LA enlargement (LAE).
-
1.5 is considered abnormal.
- This measurement is very operator-dependent.
Clinical Relevance of LA and LV Measurements
- Used in the diagnosis and management of Degenerative Mitral Valve Disease (DMVD).
- The ACVIM consensus guidelines for DMVD diagnosis and treatment use these measurements.
- For asymptomatic dogs, pimobendan treatment is initiated if:
- LVIDdN > 1.7
- LA:Ao > 1.6
- Treatment based on Boswood et al. 2016 (EPIC trial).
- Also used to assess the clinical relevance of LV wall thickness in dogs with systemic hypertension.
Assessment of the Right Heart
- The right heart has a unique shape and anatomy (flat conical shape that wraps around the left heart).
- Assess the size and thickness.
- RV wall is thinner than LV.
- Assessing the right heart is more nuanced and complicated.
- Eyeballing art: The right heart should look smaller than the left heart (RA ‹ LA, RV ‹ LV).
- The interventricular septum (IVS) should curve towards the RV due to lower pressure.
- Disproportionately large right heart indicates abnormality.
Assessment of the Heart in Cats
- The most common disease is hypertrophic cardiomyopathy (HCM), resulting in thickened and stiff ventricular walls with diastolic dysfunction.
- Key measurements: LV wall thickness and LA size.
- LA size is the most important index to guide therapy and prognosis.
- Measurements are usually not normalized.
- Important numbers:
- Any LV segment > 6 mm indicates HCM.
- Normal LVIDd ~11-18 mm.
- Normal LA:Ao < 1.3; >1.6 indicates enlargement.
- Systolic function is usually high-normal, but can be reduced in end-stage disease.
Doppler Echocardiography
- Blood flow follows two principles: driving pressure and path of least resistance.
Mitral Inflow Profile
- The mitral valve opens at the beginning of diastole, with early filling driven by left atrial pressure (LAP).
- High LAP is the end-product of all left heart diseases.
- E wave velocity increases as left atrial pressure increases (non-linear).
- Normal values:
- E < 1 m/s
- A < 0.8 m/s
Ventricular Outflow
- Normal outflow velocity for aortic and pulmonary valves < 2 m/s.
- Elevated velocity can indicate outflow obstruction (stenosis) or increased blood flow (increased preload or shunt).
- Small, instantaneous pressure gradients mean ventricular pressure rises faster than blood pressure.
- Doppler is used to assess the severity of obstruction and estimate driving pressure.
- Valve Regurgitation: Doppler assesses how high or low the pressure within the driving chamber (higher/lower than expected?).
- Cardiac Shunts: Blood that flows from a high-pressure (systemic) to low-pressure (pulmonary) system.
- Medical ultrasound cannot measure pressure directly.
- Doppler measures blood flow velocity.
- Velocity is used to estimate the driving pressure or pressure gradient (PG) across the orifice.
Doppler and Blood Flow: Principles
- Apply Continuity of flow Conservation of mass: A1 x V1 = A2 x V2↑
- Apply Bernoulli's principle Conservation of energy
- P1-P2 = ½p(V22 - V12) + ∫12 dv/dt x ds + R (v)
- Extended Bernoulli's equation for unsteady flow:
- P1 - P2 = ½ρ(V22 - V12) + ∫12 dv/dt x ds + R (v)
- Pressure decrease = convective + flow + viscous
- acceleration acceleration friction
Solving Pressure Gradients (PGs)
- Simplified Bernoulli's equation (used for stenosis, valve regurgitation, or shunts):
- P1 - P2 = 4V2
- Assumptions for simplification:
- A small mass of fluid is being accelerated through a small hole.
- Energy loss due to viscous friction is minimal
- V₁ (proximal velocity) is close to 1-1.5 m/s
Examples of Normal Pressures:
| Site | Systolic | Diastolic | Mean |
|---|---|---|---|
| RA | - | - | 3 (±2) |
| RV | 25 (±5) | 0-5 | - |
| PA | 25 (±5) | 10 (±3) | 15 (±5) |
| PA wedge | 6 (±2) | 4 (±2) | 5 (±2) |
| LA | - | - | - |
| LV | 120 (±20) | 0-8 | - |
| Aorta | 120 (±20) | 90 (±10) | 100 (±10) |
| Femoral artery | 130 (±20) | 90 (±10) | 100 (±10) |
Clinical Applications of Doppler Pressure Gradient
- Case 1: 6-month-old French Bulldog with a murmur diagnosed with congenital pulmonary stenosis.
- Pulmonary valve velocity = 5 m/s
- Pressure gradient (PG) = 4 x 52 = 100 mmHg
- RVSP = 100 + 20 = 120 mmHg (assuming normal PA pressure)
- Case 2: 7-year-old Pit Bull presented for syncope and diagnosed with pulmonary hypertension.
- Tricuspid regurgitation velocity = 5 m/s
- PG = 4 x 52 = 100 mmHg
- RVSP = 100 + 5 = 105 mmHg (assuming normal RA pressure)
- PASP = RVSP = 105 mmHg
Cautions for Doppler Echocardiography
- Doppler echocardiography is highly operator dependent with high variability, especially spectral Doppler.
- Doppler findings should be integrated into all other measurements.
- Base clinical decisions on patients, not solely on numerical Doppler values.
Studying That Suits You
Use AI to generate personalized quizzes and flashcards to suit your learning preferences.
