the comprehensive fetal echo protocol - north carolina … · · 2018-02-09the comprehensive...

The Comprehensive

Fetal Echo Protocol

A PEDIATRIC CARDIOLGY PERSPECTIVE

John Lockhart, BSRT, RDCS

Pediatric and Fetal Echocardiographer

Duke Pediatric Echo Lab

John Lockhart BSRT, RDCS

Why this Talk?


Diagnosis and

treatment of fetal cardiac disease: A scientific statement from the American Heart Association. Journal Issue: Circulation, 129(21). http://circ.ahajournals.org/content/early/2014/04/23/01.cir.0000437597.44550.5d


http://www.intersocietal.org/echo/

http://asecho.org/pediatricsneonatalcongenital/

http://www.aium.org/resources/guidelines.aspx

http://www.isuog.org/NR/rdonlyres/14895030-9283-4DB6-9CF7-BF9304DAB0B5/0/ISUOG_cardiac_screening_guidelines_aspublished_2013.pdf

http://circ.ahajournals.org/content/early/2014/04/23/01.cir.0000437597.44550.5d

• Create a protocol that satisfies IAC requirements

• Go above minimum protocol and add recommended

views from groups you trust like ASE, AIUM, ISUOG

and AHA

• Revaluate your protocol every few years and make

adjustments


Journal of the American Society of Echocardiography Volume 17 Number 7

1. Diagnosis and treatment of fetal cardiac disease: A scientific statement from the

American Heart Association. Journal Issue: Circulation, 129(21).

2. Compares protocols from several sites including their own recommendation

3. Article can be found here.


J Am Soc

Echocardiogr

2004;17:803-10.

Circulation, 129(21).John Lockhart BSRT, RDCS


Protocol Checklist

• Create a checklist and use

it!

• May want to laminate your

checklist and hang it on

your machine

• Can use dry erase markers

to fill it out


2. Take the images in the order the baby gives them to you – use

protocol checklist

3. Use ribs and spine as your guide, try to keep cuts true. Try to

keep ribs the same length on both sides when performing

transverse cuts of fetus so you won’t be off axis

4. Try scanning fetus with mom in different positions, try on her

side or reverse Trendelenburg for morbidly obese

5. When your stuck, get the baby to move – find the biggest pocket

of fluid and roll mother on side that will drop the fetus into the

fluid. Wait 5 minutes and roll mom back. Will usually get baby to

move.


Fetal Cardiac ExamFetal position and cardiac/visceral situs

Vertex or Breech

1. Sweep from cervix to fundus with transducer marker at 3 O'clock to demonstrate

fetal lie in relationship to mother

2. Determine fetal sidedness. I like right hand technique. Bronshtein M1, Gover A, Zimmer EZ.

Sonographic definition of the fetal situs. Obstet Gynecol. 2002 Jun;99(6):1129-30

3. Label head position, posterior/spine and left side of fetus

4. Look for position of heart and cardiac axis

5. Assess location of stomach bubble, liver, descending aorta, IVC and bladder as you

sweep


Fetal Cardiac ExamFetal position and cardiac/visceral situs

Vertex or Breech


• Levocardia – heart is in the left chest - Normal

• Dextrocardia – heart is in the right chest

• Mesocardia – heart is in the midline

• Does not necessarily tell you anything about looping or heart disease

• Abnormal position is associated with congenital heart disease

especially with abnormal relationship between cardiac and abdominal

situs-Heterotaxy

• You can have abnormal cardiac position with normal cardiac anatomy,

cardiac malposition can be related to external pressure from masses or

diaphragmatic hernia


• Should be approximately 45 degrees

• Abnormal cardiac axis is associated with congenital heart disease and increase morbidity

• Study “Abnormal fetal cardiac axis in the detection of intrathoracic anomalies and congenital heart disease” by Crane et al Ultrasound in Obstetrics and Gynecology 10(2):90-3 · August 1997

• Study of 409 fetal patients, 23 of 32 fetuses with abnormal cardiac axis had congenital heart disease

Cardiac Axis


Transverse fetal position1. If fetus is transverse I prefer Mayo Clinic method – Distinguishing Right From Left: A

Standardized Technique for Fetal Echocardiography JASE January–February, 1994Volume 7, Issue 1, Pages 47–53

2. Sweep from cervix to fundus with transducer marker at 3 O'clock to demonstrate fetal lie in relationship to mother (head maternal right or left)

3. Obtain long axis of the fetal spine with head to right of screen and rotate clockwise 90 degrees

4. Label head position, posterior/spine and left side of fetus and take still frame


http://www.onlinejase.com/issue/S0894-7317(14)X8411-7

Apical Four Chamber Sweeps-2D

• Start sweep posteriorly - assess coronary sinus

• As you sweeping anteriorly – midway assess crux of the heart, AV valves, chamber sizes

and morphology

• Continues sweeping cephalad, assess ventriculaoarterial relationship ( crisscross ) all of the

way through the neck to assess size of great arteries, aortic arch sidedness and branching

pattern as well as venous anatomy


Apical Four Chamber Sweeps -Color• Scan the interventricular septum for large ventricular defects,

not a good angle for picking up small defects

• Good angle for picking up MR and TR

• Can pick up pulmonary veins as you sweep through left atrium

• Good view to assess ascending AO and ductus arteriosus by color flow Doppler


Subcostal Four Chamber Sweep-2D

• Same anatomy as apical view but better at visualizing atrial septum and ventricular septum

• Perform the sweep the same starting with coronary sinus through the head and neck vessels


Subcostal Four Chamber Sweep-Color

• Scan interventricular septum thoroughly - drop your Nyquist limit into the 50s

• Best view for assess ventricular level shunts

• Pulmonary veins and atrial level shunt are well visualized from this view

• Sweep all the way posteriorly through coronary sinus and anteriorly till you are out of

the heart


Short Axis Sweep• Start from apex of heart all the way through the arches

• Structures visualized include Ao Arch, Ductal Arch, RVOT, PV ,MPA,

PA branches, AOV, MV and entire ventricular septum


Short Axis Sweep-Color• Sweep all the way through the ventricular mass and arches

• Drop Nyquist limit to help screen for ventricular septal defect

• Pay attention to color flow in arches for aliasing, ductal restriction


ClipsApical Four Chamber View

• Crux of the heart – Atrioventricular valve level (MV,TV, common valve)

• Size and morphology of ventricles (moderator band, chordal attachments)

• Size of atria

• 2D of pulmonary veins

• Coronary sinus with posterior angulation


• Look for atrioventricular valve

regurgitation (MR and TR)

• Usually see at least one

pulmonary vein

ClipsApical Four Chamber View -Color


• Crux of the heart – primum atrial septal defects, inlet and muscular ventricular septal defects

• Chamber sizes

• Flap of the foramen

• 2D of pulmonary veins

ClipsSubcostal Four Chamber View


ClipsSubcostal Four Chamber View - Color

• Best view for picking up ventricular level shunts by color Doppler, sweep septum as

you clip

• Evaluate atrial level shunt

• Good view to assess pulmonary veins


LVOT• Mitral aortic valve continuity

• Size of MV, AOV, and ascending aorta


ClipsLV and MV SAX

• Assess biventricular function

• Make sure you see anterior leaflet of the MV, rule out a cleft


RVOT• Assess infundibulum, PV, main pulmonary artery

• Establish that RVOT crosses LVOT

• Short axis view – assess conal septum, infundibulum, PV, MPA and branch pulmonary

arteries (PSAX)

• With slight angulation you should see ductus arteriosus


ClipsPSAX and AOV

• Zoom on aortic valve and leaflets to assess mobility


ClipsAortic and Ductal Arches

• Show head vessels on aortic (hairy) arch

• Ductal (bald) arch more hockey stick in appearance


Aortic and Ductal Arches- Color

• Look for aliasing


Special Views3 Vessel View

• Structures visualized: Superior Vena Cava and innominate vein, ascending aorta and

isthmus, main pulmonary artery ductus arteriosus and trachea

• Assess size discrepancies between vessels - can be subtle indicator of pathology

• Sweeping will demonstrate arch sidedness, arch branching as well as venous anatomy.


Special Views3 Vessel View Continued

• Sweeping will demonstrate arch sidedness, arch branching as well as venous anatomy.

• Put color flow on innominate vein to prove it is a venous structure


Bicaval View

• Structures visualized: Superior Vena Cava, right atrium, inferior vena cava, hepatic veins


Pulmonary Veins• Must see at least one left and one right pulmonary vein

• Drop Nyquist limit way down to identify pulmonary veins easier.

• Use small sample size and pulse out in parenchyma

• 4 chamber views or short axis views

• Pulsed wave Doppler at least one right and one left pulmonary vein


• Cone shaped structure that serves to restrict flow and direct it across the atrial septum

• Easily identified by aliasing of color flow Doppler

• Flow profile very important to assess fetal circulatory state and cardiovascular health

• Very small structure so use a small sampling gate when interrogating with PW Doppler, 1 to

2mm

Ductus Venosus


Ductus Venosus

• Look for decreased A –wave, A-wave reversal sign of increased right atrial pressure


Ductus Venosus

• Reversal of flow can be an indicator of poor fetal circulatory state

• With certain right heart lesions can be an expected finding, Tr Atr, HRH, due to elevated

right atrial pressure


RhythmPW Doppler and M-Mode

• We record mechanical PR on every patient (not required)

• Place pulsed wave Doppler sample between MV and AoV in apical 4ch or LAX view, widen Doppler sample so that it covers both part of AoV and MV, about

4mm

• Obtain heart rate from aortic flow clicks

• Assess rhythm from M-Mode


SVT


Congenital Heart Block


Measurements• Measure diameter of all four valves, Boston Z-scores database available at

http://zscore.chboston.org/

• Record Z-scores in report for all valves

• Measure aortic isthmus and ductal isthmus

• 3VV measure MPA and AAO if they look abnormal

• Measure LV and RV length and diameter


http://zscore.chboston.org/

• Increases throughout pregnancy, 11-12 weeks ~ .38, 17 to 20 weeks ~

.45, Term ~ .5

• Should always be . 5 or less

• Predictor of extent of lung compression, poor outcomes

• Critical in patients with severe TR (TV dysplasia, Ebstein’s anomaly)

and often associated with hydrops

• Increased CT ratio often seen with complete heart block~NORMAL EBSTEIN’S CHB


Gestational Age

1. All our patients are referrals -in cardiology we used to always take gestational age from OB reports

2. Guidelines now require us to measure gestational age ourselves

3. Must obtain a FL, BPD or head circumference

4. We use FL, for us it’s the most reproducible


Doppler• All four valves, use CW if above Nyquist limit

• Ductus arteriosus and aortic isthmus

• Ductus venosus, umbilical artery, umbilical vein and middle cerebral

artery (MCA)


Umbilical Vein

• Normal cord has three vessels, two arteries and one vein.

• Two vessel cord has increased risk of congenital anomalies including cardiac

• Pulse a free loop halfway between placenta and insertion

• Gate large enough to capture vein and artery at same time

• Umbilical vein carries oxygenated blood to fetus

• Pulsations in vein can be indicative of cardiac disease

• Diastolic pulsations - cardiac diastolic dysfunction

• Systolic pulsations – severe tricuspid regurgitation

• Use UA for reference for timing


Umbilical Artery

• Carries fetal circulation to the placenta

• Has a significant amount of diastolic flow due to low

resistance in the placenta

• Not shown to be related to congenital heart disease

• We utilize the pulsatility index (PI) when evaluating twin to

twin transfusion or IUGR


MCAMiddle Cerebral Artery

• Located off the circle of Willis

• You want to sample halfway between where it takes off and the cranial wall

• Cerebral vascular resistance is normally higher than placental vascular resistance and therefore the pulsatility index is higher in the MCA than UA

• MCA PI index will decrease with fetal circulatory states that compromise cerebral flow as the body attempts to shunt blood flow back to the vital organs such as the brain.

• Conditions such as IUGR, Twin to Twin, cardiomyopathy can cause an decrease in cerebral vascular resistance in order to increase flow


Special ViewsDuctus Venosus

• Cone shaped structure that serves to restrict flow and direct it across the atrial septum

• Easily identified by aliasing of color flow Doppler

• Flow profile very important to assess fetal circulatory state and cardiovascular health

• Very small structure so use a small sampling gate when interrogating with PW Doppler, 1 to

2mm


Fetal

Hypoplastic Left Heart

Newborn

Hypoplastic Left Heart

Pathology HLH


Normal at 14 1/7 Weeks TOF at 13 1/7 weeks


Images courtesy of A Moon - Grady, UCSFJohn Lockhart BSRT, RDCS

•Be regimented and disciplined in

your protocol

•Use a checklist

•Be stubborn, don’t give up till

you figure out the puzzle


THANK YOU


Please feel free to contact me if you have any

questions about a pediatric echo

• Duke University Hospital

• [email protected]

• Work Phone # 919-681-5166

• Cell# 214-649-9086

mailto:[email protected]

the comprehensive fetal echo protocol - north carolina … · · 2018-02-09the comprehensive...

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