Description
Book SynopsisDoppler Echocardiography for the Small Animal Practitioner Practical guide to using color flow and spectral Doppler in interpreting echocardiographic findings in veterinary practice Doppler Echocardiography for the Small Animal Practitioner provides a clinically oriented quick reference to using color flow and spectral Doppler to interpret echocardiographic findings, enabling readers to learn and apply these techniques and acquire background knowledge of technical factors affecting diagnostic color and spectral Doppler. Practically, the text also serves as a quick checklist for the Doppler features of commonly acquired cardiac diseases in the dog and cat. To aid in reader comprehension, the text contains color images and video clips to support the descriptions. This handbook is not intended as a comprehensive explanation of the echocardiographic features associated with heart disease in animals. Rather, it is intended as the next step for the general practitioner and the non-cardiac s
Table of ContentsPreface xi
About the Companion Website xiii
1 The Basics: What You Need to Know 1
Doppler Principles as They Apply to Accuracy and Quality of the Exam 1
Doppler shift 1
Types of Doppler 2
Advantages and disadvantages of each type of Doppler 4
The spectral display 4
The color display 6
Nyquist limit and aliasing 8
Accuracy of spectral flow information 12
Optimizing Doppler Displays 14
Color flow 14
Spectral Doppler 19
Laminar and Turbulent Flow 21
Normal laminar flow 21
Turbulent flow 21
Causes of spectral broadening 22
2 The Doppler Examination 23
Spectral Doppler 23
Normal spectral flows in the heart 23
Mitral valve 23
Aorta and LVOT 26
Pulmonary artery and RVOT 27
Left ventricular isovolumic relaxation time (IVRT) 31
Pulmonary venous flow 32
Left auricular flow 32
Color Flow Doppler 37
Normal color flow in the heart 37
Mitral valve 37
Aorta 38
Pulmonary artery 43
Tricuspid valve 47
3 Applications 55
Pressure Gradients (PGs) 55
PG meaning 55
Normal pressures in the heart and vessels 55
Bernoulli equation 55
Modified equation 55
How can blood flow when pressures in the ventricles and great vessels are the same? 57
Factors Affecting Flow Velocities 57
Volume 57
Narrowed pathway 57
Pressure 57
Limitations of the simplified Bernoulli equation 59
Common Applications of PG in Acquired Heart Disease 59
Using mitral regurgitation 59
Hypertrophic cardiomyopathy 62
Pulmonary hypertension 63
Diastolic Function and Doppler 66
Definitions 66
Classes of diastolic dysfunction 66
Overview of diastolic function 72
4 Doppler Features in Common Acquired Cardiac Diseases 77
Chronic Valve Disease 77
2D and M-mode features 77
Color flow evaluation 77
Spectral Doppler 80
Dilated Cardiomyopathy 82
2D and M-mode features 82
Color flow evaluation 84
Spectral Doppler 84
Hypertrophic Obstructive Cardiomyopathy 84
2D and M-mode features 84
Color flow evaluation 85
Spectral Doppler 87
Diastolic function 88
Dynamic Right Ventricular Outflow Tract Obstruction (DRVOTO) 88
2D and M-mode features 88
Color flow evaluation 90
Spectral Doppler 90
Nonspecific Cardiomyopathy 90
2D and M-mode features 90
These result in diminishing systolic function 90
Color flow evaluation 90
Spectral Doppler 91
Pulmonary Hypertension 92
2D and M-mode features 92
Color flow evaluation 93
Spectral Doppler 93
Appendix 1 Spectral Doppler Reference Ranges for the Dog and Cat 99
Appendix 2 Abbreviations 103
Recommended Reading 105
Index 107
