Basic Veterinary Echocardiography
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Transcript of Basic Veterinary Echocardiography
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Basic Veterinary EchocardiographyThe Subject for a Radiologist?
Daniel A. Feeney DVM, MS
Professor of Veterinary Radiology
College of Veterinary Medicine
University of Minnesota
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Transducer Configuration
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What is Echocardiography?
• High Hz Sound– TRANSMITTED– REFLECTED– TRANSLATED into time-associated image
(graphic 2-D)
Goals of Current Discussion• COMPARE Echocardiography to Survey &
Contrast Radiography• Introduce BASIC Technical Aspects of
Echocardiography• Introduce ELEMENTARY Interpretive Principles
of Echocardiography• Focus on Diagnoses for the GENERALIST
• Radiologist doing echocardiography = plumber doing neurosurgery?
Justification for Echocardiography
• Shortcomings of Survey Radiography– hypertrophy vs. dilation– no information cardiac function– no information on valves– no information on internal cardiac anatomy– miss masses (pericardial sac or heart)– pleural fluid problems
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Justification for Echocardiography
• Shortcomings of Contrast Radiography(particularly angiography)– contrast media risk– nonselective angiography +/- for shunts– selective angiography
invasiveanesthesia riskspecialized equipment
Justification for Echocardiography
• Shortcomings of Contrast Radiography(particularly angiography)– pericardial sac procedures (e.g.
pneumopericardiogram)invasiveanesthesia riskembolism & hemorrhage risk
Justification for Echocardiography• noninvasive• no contrast media risk• sector scanners applicable for general abdomen, etc.• hypertrophy vs. dilation• quantitate cardiac function • find masses in the pericardial sac or heart (not
100%)• no pleural fluid problems• information on internal cardiac anatomy
& valves
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Applications of Echocardiography• determine size and quantitate function of cardiac
chambers• identify intracardiac or pericardial sac masses (or
vegetations)• non-invasively reevaluate indices of cardiac function
after Rx• clarify origin of pleural fluid
Technical Considerations
• Windows– [R, 4-5] parasternal intercostal (M-mode standard)– [L, 3-4] cranial parasternal intercostal– [L, 5-6] caudal parasternal intercostal (apical)
Technical Considerations
• Transducer Configuration/Frequency (Hz)– “inline” configuration
– Use Hz that will put area of interest in focal zoneof transducer
horses/cattle 2.25-3.5 MHzmedium/large dogs 3.5-5.0 MHzsmall dogs/cats 5.0-7.5 MHz
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Cardiac Notch
From:Boon J, Wingfield WE &
Miller Cw:
Echocardiographic Indices
in the Normal Dog.
Vet Radiol 24:214-221,
1983.
Technical Considerations• Cardiac Anatomy vs. Ultrasound Display Modes/Views
M-mode Real-time, sector, 2D** Two-dimensional Views
R parasternal long axisR parasternal short axisL (cranial parasternal long axisL (caudal) [apical] parasternal long axisL parasternal short axis
Technical Considerations• Cardiac Anatomy vs. Ultrasound Display
Modes/Views– “M-mode easiest method by which to obtain
cardiac dimension.”– “The 2-D is generally superior in identification of
cardiac masses, atrioventricular septal defects, regional wall disorders and heartworms.”
(Bonagura, O’Grady & Herring: VCNA(SA) 15:1177, 1985)
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Anatomy
Anatomy
Basics of Interpretation
• What Parts Have You Identified (is the study complete)?– Valves
aortic semilunar (M-mode & 2-D)mitral (M-mode & 2-D)pulmonic (2-D)tricuspid (M-mode & 2-D) [BEST-LCrP/S L-Aor LCrP/S S-A]
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Basics of Interpretation
• What Parts Have You Identified (is the study complete)?– Chambers
left atrium (M-mode & 2-D)left ventricle (M-mode & 2-D)right ventricle (M-mode & 2-D)right atrium (2-D) [BEST-LCaP/S L-A (apical) view]
Basics of Interpretation
• What Parts Have You Identified (is the study complete)?– Miscellaneous Structures
chordae tendinae (M-mode & 2-D)pericardium (M-mode & 2-D)papillary muscles (M-mode & 2-D)endocardium (M-mode & 2-D)
Technical Considerations
• Contrast Echocardiography– Use of saline, green dyes, aggregated albumen, etc.
to create echogenic fluid or bubbles which will flow with the blood and identify its course
– Use for identifying shunts
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Making Sense of M-mode
From:Feigenbaum H:
Echocardiography (3rd
edition)
Lea & Febiger,
Philadelphia, 1981.
Long-axis, R L
From:Thomas WP:
Two-dimensional, Real-
time Echocardiography
in the Dog – Technique
& Anatomic Validation.
Vet Radiol 25:50-64,
1984
Long-axis, R L
From:Thomas WP:
Two-dimensional, Real-
time Echocardiography
in the Dog – Technique
& Anatomic Validation.
Vet Radiol 25:50-64,
1984
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Long-axis, R L
R L Long Axis (loop)
Doppler: Duplex/Color-flow
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Short-axis, R L
From:Thomas WP:
Two-dimensional, Real-time Echocardio
in the Dog – Technique & Anatomic
Validation. Vet Radiol 25:50-64, 198
Short-axis, R L
From:Thomas WP:
Two-dimensional, Real-time Echocardiog
in the Dog – Technique & Anatomic
Validation. Vet Radiol 25:50-64, 1984
Short-axis, R L
From:Thomas WP:
Two-dimensional, Real-time Echocardiogra
in the Dog – Technique & Anatomic
Validation. Vet Radiol 25:50-64, 1984
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Short-axis, R L
4-chamber, L R/M-mode, R L
4-chamber, L R
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Basics of Interpretation
• Are These Structures Basically Normal?– ? chambers conspicuously dilated or compromised– ? contractility = 30%, rate & rhythm– ? any percardial fluid [vs. pleural fluid]– ? any masses or vegetations– ? CVC persistently dilated, 4-5 level hepatic vein
branches seen– ? obvious spontaneous contrast in the
chambers
Basics of Interpretation
• On Further Practical Scrutiny, Are They Sill Normal?– ? is ECG normal– ? is mitral valve motion normal [AMV = “M”]– ? paradoxical septal motion
Basics of Interpretation
• On Further Practical Scrutiny, Are They Sill Normal?– Relevant Generalities
• right ventricular free wall = 1/3-1/2 as thick as ventricular free wall in small animals (Bonagura, Herring: VCNA(SA) 15:1195, 1985)
• excessive “E-point” [1st hump of AMV’s “M”] to septal separation consider left ventricular dilation or failure (Bonagura, O’Grady & Herring: VCNA(SA) 15:1208, 1985)
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Basics of Interpretation
• Relevant Referenced Normal Parameters By Species– Dog-many dimensions proportional to body size1
– Cat-only weak relationship between dimensions & body size2
– Horse-most dimensions not specified as varying with breed/size3
1 Bonagura, O’Grady & Herring: VCNA(SA) 15:1208, 1985Boon, Wingfield & Miller: Vet Radiol 24:214, 1983O’Grady, Bonagura, Powers & Herring: Vet Radiol 27:34, 1986
2 Bonagura, O’Grady & Herring: VCNA(SA) 15:1208, 19853 Bonagura, Herring & Welker: VCNA(SA) 2:311, 1985
Basics of Interpretation
• Relevant Referenced Normal Parameters By Species– “There is good agreement between 2-D & M’moade
indices of heart size except for the left atrial side, whick is measurably larger within 2/d.”4
4 Bonagura, Herring: VCNA(SA) 15:1995, 1985
Basics of Interpretation
• Measurement Standardization ≈ that used for humans:
Sahn DJ, DeMaria A, Kisslo J, et.al.: Circulation 58:1072-1083, 1978. [M-mode Echocardiography]
Henery WL, DeMaria A, Gramiak R, et.al.: Circulation 62:212-217, 1980 [2-D Echocardiography]
– Leading edge method– Systolic measurements “nadir of septal motion”– Diastolic measurements “onset of the QRS
complex”
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Canine Measurement Scheme
Boon J, Wingfild WE & Miller CW:Echocardiographic Indices in the Normal DogVet Radiol 24:214-221, 1983
Canine Measurement Scheme
Bonagura JD, O’Grady MR & Herring DS:Echocardiography – Principles of InterpretationVet Clin North Am (SA) 15:1177-1194, 1985
Canine Dilatory Cardiomyopathy
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Canine Dilatory Cardiomyopathy
Canine Dilatory Cardiomyopathy &L Atrial Clot
Feline Hypertrophic Cardiomyopathy
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Feline Hypertrophic Cardiomyopathy
Feline Dilatory Cardiomyopathy
Feline Dilatory Cardiomyopathy
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Pericardial Infusion Bullet
Pericardial Infusion Bullet
Pericardial Fluid + Masses (clots)Endocarditis (cow)
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Heartbase Mass
Heartbase Mass
Mitral Endocardiosis
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FLOW
BASELINE0
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2 Venous Flow
Respiratory/Cardiac Periodicity
Arterial FlowHigh-resistance Low-resistance
fD =2v (cos ) f
cT
Doppler Principle
4-Chamber, Mitral Regurgitation
Long Axis, Mitral Regurgitation
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Mitral Regurgitation
Endocarditis (aortic valve)
Aortic Stenosis Valvular/Subvalvular
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VSD (foal)
Invasive Retroperitoneal Mass
Sublumbar Lymphadenopathy
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