Exam 3

PLSA- Parasternal Long Axis View

• 2D echo- real time imaging of the heart

• First view obtained in a echocardiography examination

• Transects the heart from base to the apex (sliced in half/across) with the apex toward the left and base toward the right

Patient Position and Preparation

• Basic 3 leads EKG- to monitor patient HR and rhythm

• Lay on your left side w/ arm above head and right arm on your side

AKA Left Lateral Decubitus position- preferred as gravity displaces the cardiac apex closer to chest wall

• Transducer should be on the left side sternum 2nd to 3rd ICS w/ index facing patient right shoulder- only a starting point

Obtaining PSLA

• The exact orientation depends on the axis of the patients heart (the starting point)

• Usually you can’t see apex so you should try to display LV as lengthened or long as possible

• Index marker on the screen for echo is on the right

• Depth is around 12-16 cm, however it’s not for everyone, it depends on the patients anatomy

Breathing Technique: Breath Normally

• When lungs interfere, hold or push out all the air and hold their breath

• Experiment to obtain the best picture

Transducer Movements

• Tilt/Angle- stays in same imaging axis, face of the transducer is manipulated to demonstrate different image planes.

  • Ex: Inferior/Superior

• Rotate- stays in same position, index orientation is rotated to different position

  • Ex: Clockwise/Counter-Clockwise

• Rocking- stays in same imaging plane, moved towards or away form the index marker

• Slide- physically changing the location of the transducer

  • Ex: Sliding from one rib to another rib space

Transducer

Phased Array- Cardiac range between 2MHz~5MHz

• A lower frequency has better depth penetration (ideal for adults) & poorer resolution

• 2~3.5 MHz most often used for adults

• 5MHz may be used for small adults, children or when better resolution of cardiac apex is needed to rule out a clot at apex

Homogeneous- Sonographic Appearance

Uniform gray scale

• Papillary muscles and myocardium are medium gray and homogeneous in echo texture

Echogenic- Sonographic Appearance

Reflective

• Valves are slightly more echogenic than the walls

Anechoic- Sonographic Appearance

Without echoes; just BLACK

• The area within the chambers and great vessels, as well as any other fluid space is anechoic

Hypoechoic- Sonographic Appearance

Low level echoes; darker gray

Hyperechoic- Sonographic Appearance

Brighter echoes and appears almost white

• The most reflective structure in the heart is the pericardium and appears almost white

Quality for a Good PSLA

• Septum must be horizontal as possible

• Should NOT visualize the apex of the LV, if you see it rotate your index clockwise

• See the aortic and mitral but NOT tricuspid

Overall Gain- 2D Optimization

Chamber cavities should appear anechoic, while the ventricular walls should appear gray

TGCs- 2D Optimization

(Compensate for attenuation loss)

Adjust individually optimizing specific area

• Near Field

• Mid Field

• Far Field

Depth of View- 2D Optimization

Image should be approx. 2/3rd of the screen

(distant from the surface of the skin into the body)

Focal Zone- 2D Optimization

Focus at valve level

(narrowest region of interest of the ultrasound beam that exhibits the best spatial resolution)

LGCs- 2D Optimization

Can be used for L/R side of the image

Attenuation- 2D Optimization

Refers to the inevitable loss of ultrasound wave amplitude or beam intensity

Right Ventricle(RV)- PSLA view

• located in top and closer to the probe

• Look for RV dilatation

• Also get an idea of RV Contractility

Left Ventricle(LV)- PSLA view

• Best view for the measurement of the size of the LV and wall thickness (hypertrophy) of LV

• can access the Contractility of the IVS and LVPW

Mitral Valve(MV)- PSLA view

• best view to look at is: AML- on the top/ PML- on the bottom

• You can evaluate the motion and thickness of leaflets for calcifications or MV prolapse

• Also our color on the valve to look for any MV regurgitation (backward flow of blood into the atrial)

Aortic Valve(AOV)- PSLA view

• You can see 2 or 3 aortic cusps:

  • RCC- on top

  • NCC- on the bottom

• Look at openings of the aortic cusps, you may suspect aortic stenosis(narrowing) in the presence of calcifications of the cusps or restrictions of the valve opening

• Wit color you can look for aortic regurgitation (backward flow of blood back into the ventricle)

Other PSLA view

• Aortic Roor(AOR)- you can measure the aortic annulus, LVOT and the dimensions of the AOR. The aortic walls should be parallel

• IVS-

• LVPW- you can assess their thickness and cintractility

• LA- it should be approx. the same size as the exotic root

• DA- before the LA, will help to distinguish between a pericardial effusion and pleural effusion

• PERI- the most echogenic structure appears very bright

Right Ventricular Inflow Tract (RVIT)

• From PSLA view, angle beam medial and inferior towards the right hip

• Anatomy seen: RA, RV, TV- anterior/posterior leaflets

• Helpful in evaluating diseases of the TV and other diseases of right heart. With color you can look for regurgitation (backward flow of blood into the RA)

• EV- Eustachian Vlave

Right Ventricular Outflow Tract (RVOT)

• From PSLA view, angle beam superior and lateral towards the patients left shoulder

• Anatomy seen: PV, RV, MPA

• This view AKA: Conus Arteriosus or Infubdibulum

• With color you can look for regurgitation (back flow of blood into RV)

The Heart wall is composed of 3 Layers:

Epicardium- Thin smooth outside layer and covers the surface of the heart and extends to the great vessels; it is the visceral layer of serous pericardium

Myocardium-Thicker muscular middle layer. The functional layer it is composed of striated muscle fibrils with contractile elements called Myofibrils

Endocardium-Thin layer of endothelium and underlying connective tissue. It lines the inner chambers of the heart, valves, chordae tendinae and papillary muscles

Purpose of 2D Exam

1. Identify- chamber walls and valves of the heart

2. Evaluate- size, thickness, and motion

3. Access- the anatomical relationship of these structures to rule out congenital defects

4. Document- the presence of any pathology

Right/Left Heart

Right- Pulmonary Circulation

Deoxygenated

Lower Pressure

Left- Systemic Circulation

High Pressure

Thicker Myocardium than right side

Oxygenated Blood

SVC and IVC and CS

All receives oxygen-poor blood

Superior- oxygen saturation 72%

Inferior- oxygen saturation 78%

Coronary Sinus- oxygen saturation 60%

• gathering point for oxygen-poor blood collected from cardiac veins

Pulmonary Arteries

The only arteries with oxygen-poor blood

Right and Left Lungs

Picks up oxygen and releases Carbon Dioxide waste

Pulmonary Veins

The only veins carrying oxygen-rich blood

Aortic Arch

3 branches

• Brachiocephalic or Innonimate

• Left Common Carotid Artery

• Left Subclavian Artery

Blood travels down to Descending Aorta which becomes Abdominal Aorta and then travels to all the different parts of the body

Cardiac Cycle

• The heart is a muscle that pumps blood to all parts of the body

• It acts in definite strokes or beats and in the normal adult beats 70 times per minute on average

• Consist of precisely times electrical and mechanical events that are responsible for rhythmic atrial and ventricular contractions

• Rhythmic contraction of the heart causes blood to be pumped through the chambers of the heart and out through the great vessels

• forceful contraction of the cardiac chambers is known Systole

• Relax phase of the cardiac chambers is known as Diastole

During Ventricular Diastole

• Venus blood enters the RA from the SVC, IVC and CS

• At the same time, the arterial blood returns from the lungs through the four pulmonary veins and enter the LA

• At this point the AV valves (Tricuspid and Mitral) Between the atria and ventricles are open, so the blood may flow from the atria into the ventricles

• The next phase (still ventricular diastole) Allows atrial contraction to squeeze the remaining blood from the atria into the ventricles (atrial systole)

• shortly after this phase, the ventricles contract (ventricular systole)

Ventricular Systole

• When ventricular pressure exceeds atrial pressure the AV valves close for about .05 seconds all four valves are closed. This is known as Isovolumic contraction

• as the pressure increases in the ventricles, the semilunar valves open so that blood can be forced into the lungs and body respectively

• The ventricles relax when contraction is completed. When aortic pressure exceeds ventricular pressure the semilunar valves close and once again, all four valves are closed this is known as Isovolumic relaxation (ventricular diastole)

• The blood fills the Sinuses of Valsalva, which also aids in forcing the AV to close

• When the ventricles are completely relaxed, the AV valves open and blood flows into the ventricles to begin the next cardiac cycle

Patient Position

Supine- lying on the BACK

Prone- lying face DOWN

Patient Positions or Recumbent Position

Right Lateral Decubitus- lying on the RIGHT side

Left Lateral Decubitus- lying on the LEFT side

Patient Position

Fowlers- sitting STRAIGHT UP or leaning slightly back

Trendelenberg- lying supine with the head slightly lower than the feet

Ex: when your at the dentist

Anatomical Planes

Dorsal/Posterior- pertaining to the back

Ventral/ Anterior- pertaining to the front (belly surface of the body)

Anatomical Planes

Median sagittal plane- divides into left and right sides (split in the middle)

Frontal (coronal) plane- divides into front and back (anterior/posterior)

Transverse plane- is parallel to the ground and divides into up (cranial or head) and down (tail or caudal)