septal defects

heart begins as a _____ that bulges and twists to form chambers

primal tube

_____ describes the outflow tract between the embryonic heart between the primitive ventricle and aorta

bulbus cordis

endocardial cushions form the

• atrial septum

• membranous ventricular septum

• mv and tv

exams for suspected chd should include

dynamic 10-20 sec sweeps through the structures evaluated in each view

a sternal scar indicates

open heart surgery that required cardiopulmonary bypass

a lateral scar at the 4th/5th ribs indicates

shunt placement, coarctation repair, pda litigation

situs solitus

normal arrangment

situs inversus

mirror image of normal anatomy

situs ambiguous

arrangement of abdominal organs is varied w absence of spleen or multiple spleens

apex pointing to left

levocardia

apex pointing to the right

dextrocardia

apex pointing to midline

mesocardia

rt atrium is identified by

right artial appendade (auricle) - broad junction and lots of pectinate muscle, small triangular shaped pouch attached to the rt atrium and overlaps the aorta

rt ventricle is more

trabeculated

left atrium is identified by

left atrial appendage - finger shaped pouch, narrow junction of the appendage to the left of the atrial body, less pectinate muscle

left ventricles walls are

smooth and thicker than rt ventricle

categories of adult chd

• abnormal intracardiac connections

• abnormal chamber/cessel connections

• congenital stenotic lesions

• congenital regurgitant lesions

most commonly occuring congenital cardiac anomaly (most commonly seen in children)

vsd, but many close spontaneously

most common chd seen in adults

bicuspid av, mvp and asd

small vsds are less than _____ the diameter of the aortic annulus

1/3

small vsds are _____ to flow

restrictive

large vsds are greater than _____ the size of the aortic annulus

1/2

large vsds are _____ to flow

nonrestrictive (rv and lv pressures are relatively equal)

when shunting is present, what is calculated to assess changes in the cardiac output in the rt vs lt heart

Qp/Qs ratio

normal Qp/Qs values should be

approximately 1:1

the stroke volume in the left and right ventricles should be approximately

the same

a Qp/Qs ratio indicating a significant shunt is

2:1 or higher

pulmonary cardiac output (Qp), how is this measured

• in psax at mid systole, measure rvot diameter @base of the pulmonary leaflets (inner inner) and calculate csa (0.785 x D²)

• in the same location, obtain a pw doppler tracing of the rvot flow and trace for vti

• pulmonic sv = csa x vti

• pulmonic co = sv x hr

systemic cardiac output (Qs), how is this measured

• in plax at mid systole, measured lvot diameter at the base of the aortic leaflets, calculate csa (0.785 x D²)

• in apical 5 obtain pw tracing of lvot flow that includes closing click, trace for vti

• systemic sv = csa x vti x 100

• systemic co = sv x hr

perimembranous vsd

• best evaluated in plax

• found in lvot near the aortic valve

• in psax, seen at 10-12 oclock position

• inferior to the rt coronary cusp of the aortic valve and adjacent to the septal leaflet of the tv

what is commonly seen w perimembranous vsd

• ai

• ventricular septal aneurysm

• 10% aortic valve prolapse

most common type of vsd

perimembranous vsd

muscular/trabecular vsd

• located in the muscular portion of the ivs

• best seen in the subcostal view

• “T” artifact noted in apical 4 and 5 views

• single or multiple causing “swiss cheese” appearance

second most common type of vsd

muscular/trabecular vsd

outlet/supracristal/subpulmonic/doubly committed vsd

• located in the rvot near the pulmonic valve

• best evaluated in high parasternal short and long axis views

• seen at 12-2 oclock position in psax

• inferior to the left coronary leaflet of the av and adjacent to the pulmonic valve

what is commonly seen w outlet vsd

• rt aortic cusp prolapse (60-70%)

• ai is common

inlet vsd

• located in the posterior septum, near posterior leaflet of the tv

• associated w avsd

• best evaluated in the high parasternal short and long axis views

sonographic appearance of vsds

• multiple views necessary to evaluate each type

• left heart volume overload = dilated left ventricle w hyperkinesis + la dilated

• rt ventricle usually normal but can suffer from pressure and volume overload w medium/large defects w pulmonary htn

• rt atrium not usually affected

large vsds can lead to _____ syndrome, which is

eisenmenger, rt to left shuntiing

vsd appearance of color/doppler

• shunt flow normally left to rt

• subcostal and parasternal most useful in diagnosis

• cw used to assess gradient

the higher the gradient, the _____ the defect

smaller

a Qp/Qs over _____ requires surgical intervention

1.5:1

what can be deployed via catheter to close a vsd

occlusive device

what is required for vsds that cannot be occluded w a device

open heart surgery

what is used in open heart surgery to cover a vsd

patch, stitches, piece of pericardium

post op evaluation of vsd

• evaluate for residual shunt flow around the patch or device

• assess changes to lv size/function and la size

• evaluate systolic pulmonary artery pressure to evaluate pa pressure to assess success

how is rvsp calculatde w vsd

• calculate pressure gradient across vsd w bernoulli

• systolic bp - vsd gradient = rvsp

what vsds are pictured

what vsds are pictured

what vsds are pictured

what vsds are pictured

what vsds are pictured

patent foramen ovale

• failure of the foramen ovale to close

• 25% patent in adults

what causes the foramen ovale to close in normal pts as babies

when a baby is born, the pressures drop in the rt heart, and the higher pressure in the left atrium holds the flap of tissue closed over the opening, causing it to fuse and close

how can a pfo be diagnosed

microbubbles injected into the venous system, if they appear in the left atrium within 3 cycles an asd is present

atrial septal defect (asd)

• can be associated w interatrial septal aneurysms

• defect in the septum primum layer (can be acquired due to differences in interatrial pressure)

• associated w systemic thromboembolism

most common asd

septum secundum

septum secundum asd

mid septal area, associated w mvp

second most common asd

septum primum

septum primum asd

close to mv/tv, associated w cleft mitral valve

sinus venosus asd

near svc entrance, associated w partial anomalous pulmonary venous return

coronary sinus defects

inferior portion of the septum, associated w persistent lsvc

common atrium

absence of septum, associated w ellis van creveld syndrome

signs and symptoms of asd

• murmur = systolic w a fixed split s2

• usually asymptomatic until mid to late adulthood

• dyspnea on exertion

• orthopnea

• jugular vein distension

• peripheral edema

what views are optimal for color and doppler eval of the atrial septum

subcostal

normal asd shunt flow

left to right w small amount of flow reversal at early systole

if the pressures in both atria are normal w asd, what will the average peak velocity across the defect be

about 1 m/s = approximately a 5 mmHg peak pressure gradient vc the normal difference in pressure between the right and left atrium is 5 mmHg

how will large asds appearance sonographically

will demonstrate low velocity uni or bidirectional flow, indicating increased rt atrial pressures equivalent to left atrial pressures, causing rt heart dilation from volume overload

how does rt heart dilation from volume overload appear on us (from ivs)

ivs flattening in diastole w increased rt heart pressures and a d shaped left ventricle

treatment of asd (secundum)

percutaneous transcatheter device closure

percutaneous transcatheter device closure

a device called an amplatzer can be used to close a secundum asd

• implanted using a balloon cath

• tee or intracardiac us is used to guide the procedure

what is necessary for treatment of septum primum and sinus venosus defects and why

surgical intervention, as percutaneous transcatheter device closure is not possible w those defects due to adjacent anatomy/how the device works

how will an amplatzer device look on us

echogenic disk on either side of the septum. no flow should be detected across the septum

endocardial cushion defect

atrioventricular septal defect (avsd) or av canal defect

incomplete development of the endocardial cushions

symptoms of endocardial cushion defect

• holosystolic murmur

• dyspnea

• cyanosis

• fatigue

what is endocardial cushion defect associated with

down syndrome

partial endocardial cushion defect

septum primum asd

cleft mitral valve

complete endocardial cushion defect

septum primum asd

inlet vsd

common atrioventricular valve w 5 leaflets

sonographic appearance of avsd

• apical views demonstrate the av valves, primum asd and inlet vsd

• common av valve appears as a single linear structure between the ventricles and atria (lack of normal offset of tv toward apex)

• subcostal views are best for color/doppler eval

• leads to rt ht volume overload, dilated rt ventricle w paradoxical ventricular septal motion