Introduction to echocardiography Flashcards
What is echocardiography?
• ECHO is the use of ultrasound to examine the heart.
What are the different types of array on a logic V2 echocardiography machine?
Curvilinear
Phased Array (may be swept electronically w/out moving probe)
Linear
Describe linear array transducers
- Images obtained with linear arrays always have a flat superficial surface and are designated on the image with the letter L followed by the transmit frequency.
- For example, a transducer with the notation HFL38/13-6 indicates that it is a high-frequency broadband (13-6 MHz) linear transducer with a 38-mm footprint.
- High-frequency sound does not penetrate deeply into tissues, so high-frequency probes are only useful for superficial structures.
Describe curved array transducers
- If the surface of a linear array is reformed into a curved convex shape, it is called a curved array, curvilinear array, or a convex array.
- Curved arrays can be formed in different sizes and shapes. Probes with a short radius of curvature can be used for endoluminal scanning and probes with a larger radius of curvatures can be used for general abdomen and obstetrical scanning.
- Images obtained with curved arrays always have a curved superficial surface and are designated on the image with the letter C followed by the transmit frequency.
Describe phased array transducers
- With the phased-array transducer, every element in the array participates in the formation of each transmitted pulse.
- Because the sound beams are steered at varying angles from one side of the transducer to the other, a sector image format is produced.
- The phased-array probe is smaller and therefore capable of scanning in areas where acoustic access is limited, such as between ribs.
What are the US probe manipulation manoeuvers “PART”?
- Pressure
- Alignment (movement)
- Rotation
- Tilting (fanning)
Discuss probe and image orientation
- The US image must be properly oriented to accurately identify the anatomic relations of the various structures on the monitor.
- To facilitate this, all US probes have an orientation marker, which is usually represented by a groove or a ridge on one side of the transducer and corresponds to a green dot (or a logo) on the monitor.
- By convention, the orientation marker on the transducer is directed cephalad when performing a longitudinal scan and directed toward the right side of the patient when performing a transverse scan.
- This way the orientation marker on the left upper corner of the monitor always represents the cephalad end during a longitudinal scan or the right side of the patient during a transverse scan.
- The top of the display monitor therefore represents superficial structures and the bottom of the monitor the deep structures.
What is the best transducer and echo frequency range for a typical transthoracic echocardiogram?
A phased array at 1-5 MHz
What is an imaging window?
An imaging window refers to an anatomic position on the patient’s body where an ultrasound transducer is placed to visualize specific structures.
What are the standard imaging windows for transthoracic echocardiography (TTE)?
- Parasternal. (Region on left side of the sternum superoir and equal to transverse line at height of areola in men.
- Apical. (Below left areola in men)
- Subcostal. (Along medial plane inferior to xiphisternum)
What is the surface anatomy of the heart valves?
Aortic valve - Second right intercostal space at right sternal border
Pulmonary valve - Second left intercostal space at left sternal border
Tricuspid valve - Fourth left intercostal space along lower left sternal border
Mitral valve - Fifth left intercostal space at midclavicular line (apex)
What is the M-mode?
(Motion Mode).
- The m-mode is designed to document and analyze tissue motion.
- Using the 2D image as a guide, a particular scan line is selected to correspond to the moving structure of interest.
- The reflections from this scan line are then displayed in a graphic form, with motion on the vertical axis and time on the horizontal axis.
- This mode is particularly important in studying cardiac valve and wall motion and in documenting foetal heart rate and activity.
What is the purpose of echo in resuscitation (Point of care ultrasound)?
In contrast to formal echocardiography in which multiple views and techniques provide a comprehensive structural and functional assessment of the heart, resulting in a quantitative report, basic echo in the resuscitation setting aims to answer focused clinical yes/no questions.
What should you look for in POCUS?
• In the shocked, dyspnoeic, or arrested
patient it looks for (or rules out):
• Pericardial effusion (with or without signs of tamponade)
• An enlarged RV (with or without hypokinesis and paradoxical septal motion)
• LV size, in conjunction with IVC (eg small LV suggests hypovolaemia)
• LV systolic function (rough estimate only)
What is Marfan Syndrome?
- Marfan syndrome is one of the more common disorders of connective tissue that can affect the Eyes, Skeleton, Lungs, Heart and Blood Vessels, and may be life-threatening.
- The effects of Marfan syndrome varies between individuals, some people only being mildly affected.
