20100913 os205 cardiac imaging

8/3/2019 20100913 OS205 Cardiac Imaging

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OOSS 220055:: TThhoorraaxxExam2TTooppiicc::CCAARRDDIIAACC IIMMAAGGIINNGG

[29 June 2010] Lecturer: Dr. Rogelio I. de Jesus

David, Lionel, Paul UPCM 2015 Page 1 of 7

Outline:

I. Introduction: Chest RadiographsII. Plain Film Anatomy

A. PA ViewB. Lateral ViewC. CT Scan

III. Congenital Heart DiseasesIV. Valvular Heart Diseases

I. INTRODUCTION: CHEST RADIOGRAPHS Most commonly requested diagnostic tool

Least costly and frequently effectiveEssential part of cardiac evaluation

Information obtained:Heart size and silhouetteEnlargement of cardiac chambersPulmonary blood flow/markings

Evaluation involves sequential logical assessment andcorrelation of both anatomic and physiologic information

available on PA and lateral radiographs

Patient with fever and cough. Infiltration in R lung based onx-ray. This is probably pneumonia.

Patient with chronic cough and weight loss. Both upperlobes of lungs with cavitations. This is probably tuberculosis.

Radiologists act as detectivesExtract as much info as you canCome up with a specific diagnosis that would fit all findings

II. PLAIN FILM ANATOMYA. PA View

Figure 1: Normal PA showing the borders and other visible structures.

Know relative positions of valves, atria, etc.

Know which structures are border-formingRIGHT BORDER LEFT BORDER

Superior vena cava

Right atrium

Inferior vena cava

Aortic knob

Main pulmonary artery segment

Left ventricle

Use the hila as a landmarkPulmonary arteries (PA) and bronchi are at the level of hilaPulmonary veins are below hila

Contrast study:WHITE Arteries and veins

BLACK Air-filled structures (e.g. bronchi, trachea)

B. Lateral ViewBORDERS

Left atrium (posterosuperior)

Left ventricle (posteroinferior)

Right ventricle (anteroinferior)

VISIBLE SHADOWS

Aorta

Main pulmonary trunk

Inferior vena cava

Note: Right atrium is not border-forming in the lateral view!

Note: Pulmonary arteries (left and right) and veins may bemistaken for enlarged lymph nodes in children

Figure 2: Normal lateral view showing borders and other visible structures.

C. CT Scan Axial (most requested)

Transverse cuts, as if viewed from the patients feet Your right hand side is the left side of the patient, your

left hand side is the right side of the patient

Contrast study:WHITE Bones

BLACK Air-filled structures (e.g. lungs, trachea)

GRAY Soft tissues (e.g. skeletal muscles, cardiac muscles)

Pulmonary arteries branching from main trunkMore superior on left side than right

L Pulmo.

Artery

Main Pulmo.

Trunk

R Pulmo.

Artery

LV

Aortic knob

IVC

RA

SVC

Main

Pulmo.Artery

aorta

IVC

RVLV

LA

L.Brachiocephalic v.

meeting with R.BCv

aorta

R Pulmo. Artery L Pulmo. Artery

esophagus

trachea

SVC

13 September 2010


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III. PLAIN FILM INTERPRETATIONSystemic Approach

1. OVERVIEW OR OVERALL GLANCE AT THE FILM Is it adequate or optimal for cardiac evaluation?

Erroneous data can lead to misdiagnosis.Position

Slight degrees of rotation or obliquity will substantiallyaffect the cardiac contour and may alter the apparent

size as well

Obliquity can be deceiving and may be seen as a falseenlargement

Inspiration Should be in full inspiration

Diaphragm is at the level of the 9th-10th posterioraspect or the 5

th-6

thanterior aspect of the ribs

In suboptimal inspiration or supine chest radiographs,the lower lobe markings are crowded and may obscure

the possibility of early pulmonary edema

Film should not be taken during exhalation orsuboptimal inhalation because then the superoinferior

diameter decreases and the heart is squeezed

The vessels are crowded, which could simulatepulmonary edema

Exposure Underexposure appears whiter

May simulate pulmonary congestion Overexposure appears blacker (remember:

OVERcooked rice is black, nasunog!)

May simulate emphysema, diminished pulmonaryblood flow or hypopulmovascularity

2. CARDIAC POSITION AND SITUSCARDIAC POSITION

Heart Predominantly in Apex Points Towards

Levocardia Left Left

Dextrocardia Right Right

Mesocardia Midline Down

Dextroposition

(dextroversion)

Right Left

Typically due to extrinsic forces, rotation of heart

Situs refers to the pattern of anatomic arrangement Atrial situs is usually concordant with visceral situs;

hence, these two are described together

VISCEROATRIAL SITUS

Atrium Viscera

Situs SolitusMorphologic RA is to the

right of the morphologic LA

Gastric air bubble

on left side

Liver is on the right

Situs InversusMorphologic RA is to the

left of the morphologic LA

Gastric air bubbleon right side

Liver is on the left

Situs

Ambiguous

Identification of situs not possible due to paucity of

anatomic markers (spleen and liver unidentifiable)

Note: Situs solitus is the normal condition.

Figure 3: Dextrocardia and situs solitus.

Figure 4:Dextrocardia and situs inversus.

Figure 5: Situs ambiguous.

3. Cardiac size Is heart enlarged or not?Cardio-Thoracic Ratio

Divide the widest transverse diameter of the heart bythe widest transverse diameter of the thorax taken at

the inner side of the rib cage

Figure 6: Cardio-thoracic ratio

Normal CT ratio in adults is usually 0.5 or less Normal CT ratio in the newborn is approximately 0.65 Normal CT ratio for children is between 0.5 and 0.65

(~0.6)

4. CHAMBER ENLARGEMENTRIGHT ATRIAL ENLARGEMENT

Right Heart

Border

Lateral bulging

Elongation (length exceeds 50% of the mediastinalcardiovascular shadow, midway between the

line at the root of the great vessels and the line

at the cardiophrenic sulcus)

LV

RARV


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Figure 7: RA enlargement

RIGHT VENTRICULAR ENLARGEMENT (BUDDING BREAST)

PA ViewRounding

Upliftment and lateral discplacement of apex

Lateral View

Retrosternal fullness (contact of anterior cardiac

border greater than 1/3 of the sterna length),

which may lead to false positive of LV

enlargement since there is no more room for

growth of the RV

Figure 8: RV enlargement PA view (left) and lateral view (right)

LEFT ATRIAL ENLARGEMENT

PA View

Double density on right border due to

superposition of LA (denser) and RA

Enlargement of LA appendage seen inferior to the

left main bronchus (recall that the left border is

formed by only three bulges)

Upliftment of the left mainstem bronchus

Widening of the carinal angle (normal is 70-90)due to the left mainstem bronchus being pushed

upwards (sometimes not widened when the

right bronchus is very much vertically oriented)

Lateral View

Prominent posterosuperior cardiac border (recall

that the LA is most posterosuperior chamber)

Posterior displacement and upliftment of the left

mainstem bronchus

Note: Easiest to evaluate of all the chambers.

Figure 9: LA enlargement PA view (top) and lateral view (bottom).

LEFT VENTRICULAR ENLARGEMENT

(SAGGING BREAST ORHEAVY HEART)

PA ViewLateral and inferior displacement of the apex

(which is normally border-forming)

Lateral View

Posterior displacement of the posteroinferior

border of the heart

Hoffman-Rigler sign: measured 2cm above the

intersection of diaphragm and IVC; (+) if

posterior border extends >1.8 cm of IVC

Retrocardiac fullness

Note: RV enlargement may be confused to be LV enlargement because

heart is pushed back

Figure 10: LV enlargement PA view (top) and lateral view (bottom)

5.PULMONARY VASCULAR PATTERNStart with lungsit can help in assessment

NORMAL VASCULARITY

Tapering

From inner lung zones (medial) to outer lung

zones (peripheral)

Periphery must be relatively clearer/avascular

From lung base (inferior) to apex (superior)

Lower lobes are better perfused due to gravity

Vessels in lower lobes have greater caliber

Figure 11: Normal vascularity

Hypervascularity (increased vascularity) May be seen as an overall increase in vessel caliber However, medial to lateral and inferior to superior

taperings are maintained (e.g. in shunt anomalies)

Figure 12: Hypervascularity (lateral view in powerpoint)

Double density

Inc. carinal

angle

L bronchus

uplifted

LA

appen-

dage


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Hypovascularity (decreased vascular pattern) Do not confuse with overexposed films, in which

everything is black. In hypovascularity, only the lungs

are black. (black is larger than white in relation to

pulmonary artery (white) and bronchus (black))

Found in cardiac patients of decreased pulmonaryblood flow (presence of obstruction)

Figure 13: Hypovascularity (lateral view in powerpoint)

Venous congestion Increased caliber of the vessels

Cephalization of pulmonary blood flow (vessels inupper lobes are thicker than in lower lobes)

Normal tapering from medial to lateral Do not confuse with increased arterial blood flow (e.g.

atrial septal defect), which is congenital. Venous

congestion is valvular or acquired (e.g. mitral stenosis)

Notes:

1.The terms hypervascular, hypovascular, and normovascular areused for congenital diseases.

a.Vessels/arteries/arterioles (white) and bronchioles (black) gotogether and are normally seen 1:1 in terms of size

b.In hypervascularity, the vessels are larger than the bronchiolesc. In hypovascularity, the vessels are smaller than the bronchioles2.The terms cephalization, congestion, and equalization are used for

valvular diseases.

Figure 14: Venous congestion

Kerleys B lines Horizontal lines seen in the periphery

Periphery should be relatively avascular (in normalpatients)

Indicative of fluid in the interlobular septa, as seen ininterstitial edema

Figure 15: Kerleys B-lines

Perihilar haziness

Fuzzy and blurred (as opposed to a normal radiographicimage, where vessels are distinct)

Figure 16: Perihilar haziness

Peribronchial cuffing Thick bronchioles (normal lining is hair strand-thick) Sign of pulmonary congestion

Figure 17: Peribronchial cuffing

REDISTRIBUTION

EqualizationCaliber of vessels in upper lobe is equal to that of

the lower lobe vessels

Cephalization

Caliber of vessels in the upper lobe is greater than

that of the lower lobe vessels

As seen in venous congestion

Interstitial edema Prominent horizontal lines (Kerleys B lines) Kerleys A lines: diagonal lines usually in upper lobes Kerleys C lines: tangled blood vessels with cobweb-like

appearance (facing you)

All Kerleys lines (A, B, and C) are indicative ofinterstitial edema

Alveolar edema Fluid or blood in alveoli Cotton-like appearance

Figure 18: Alveolar edema

6. THE GREAT ARTERIES/VESSELSAre they in normal position?Are they of normal size?

Aorta: normal, prominent, or diminutive (not seen)? Main pulmonary artery (seen above left main

bronchus): normal, prominent (dilated), or concave

(small, waistline is seen)?

The aorta and main pulmonary artery are for outflow. Thus,whatever is happening in the ventricle(s) is reflected in these

great vessels.


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Figure 19: Prominent aorta

Figure 20: Concave main pulmonary artery

7. ANCILLARY FINDINGS (ribs, soft tissues, chest, etc.)Calcifications

Rib notching due to coarctation of the aorta Stenotic valves

Bone deformitiesOthers

IV.CONGENITAL HEART DISEASE(See appendix for diagram of congenital heart diseases.)

Anatomic malformation of the heart and or its vessels

Occurs during intrauterine development Incidence:

8/1000 live births (most common congenital malformation)13% will have more than one cardiac defect25% will have associated non-cardiac deformity

Etiology is unknown or is multifactorial:HereditaryChromosomal abnormalityMaternal infectionTeratogenic drugsMaternal factorsEnvironmental

RADIOLOGIC INTERPRETATION OF CONGENITAL HEART DISEASE

1. Cyanotic or Non-cyanotic?2. Vascularity (hypervascular, hypovascular, cephalic, congested)3. Specific chamber enlargement4. Great Vessels (know which vessels are enlarged)5. Ancillary findingsVENTRICULAR SEPTAL DEFECT (VSD)

There is abnormal communication between LV and RVSome of the blood flows from LV to RV oxygenated blood

mixes with deoxygenated blood lungs (oxygenation of

blood) left side of heart some go to systemic

circulation, some go to right side of heart

Left to right shunt going to pulmonary circulation results inextra burden of volume

Acyanotic (oxygenated blood supplies systemic circulation) Radiographic findings:

Increased vascularity due to increase in blood volumetowards the right side

Enlargement of main and central pulmonary arteriesEnlargement of left ventricle due to strain on LV(also in left

atrium, but less noticeable)

Enlargement of right ventricle, but only in a large defect(shunting of blood in both systole and diastole)

Aorta is small or normal

If uncorrected, leads to pulmonary hypertension as one agesLungs vasoconstrict to counter too much blood flowRV

hypertrophies (pressure overload)shunt is

reversedblood going into systemic circulation is mixed

cyanosis (EISENMENGERIZATION)

Figure 21: Diagram of VSD

Figure 22: Radiographic findings in VSD

TOTAL ANOMALOUS PULMONARY VENOUS RETURN (TAPVR)

FLOW OF OXYGENATED BLOOD

Normal

Circulation

lungs pulmonary veins LA LV aorta

systemic circulation

TAPVR

lungsright side of heart

(oxygenated blood does not drain into the left side

of the heartnot compatible with life)

ASD (obligatory shunt between atria) is needed to survive This condition leads to cyanosis Radiographic findings:

vascularity ( blood volume to right side of heart)CardiomegalyChamber prominence (right side of the heart)Enlarged systemic vein into which drainage occursPulmonary arteries dilated

Type I (Supracardiac)Connection above heart; tangle of vessels above heartLeft-sided vertical vein connects pulmonary venous

confluence to left innominate vein, right SVC or azygos vein

Snowman appearance

Chamberprominence

Inc. vascularity

Inc. vascularit

cardiome al


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Figure 23: Supracardiac TAPVR

Type II (Cardiac)

Connections to the RA or coronary sinusRadiographic findings mimic ASD but cyanotic

Figure 24: Cardiac TAPVR

Type III (Infracardiac)

Connection is below the diaphragm, to the portal vein,ductus venosus or hepatic vein

Radiographic findings: Normal sized heart Prominence of the right atrium & less often the rightventricle (due to right side involvement) Dilated pulmonary artery Pulmonary edema (most prone to edema)

Figure 25: Infracardiac TAPVR. Radiographic findings on right.

Mixed type

Various connections to the right side of the heart

Figure 26: Mixed TAPVR

TETRALOGY OF FALLOT (TOF)

Pulmonary stenosisNarrowing of the right ventricular outflow tractBlood has difficulty going to the lungsBlood from RA goes to RV but has difficulty going through

the pulmonary valve chooses an alternate route

Ventricular septal defectAlternative route chosen since there is pulmonary stenosisPressure in RV increases and deoxygenated blood is shunted

from the RV to the LV, bypassing the lungs

Less blood goes into the pulmonary circulation, resulting indecreased vascularity

Right ventricular hypertrophyDue to difficulty in propelling the blood to the lungs

Overriding aortaProminent aorta overrides VSDBlood going into the aorta is mixed, leading to cyanosis

Radiologic findings: VascularityNormal or enlarged cardiac sizeRV prominenceConcave main pulmonary artery segmentProminent aorta (right sided aortic arch in 20-25%)Small pulmonary artery

Figure 27: TOF

Figure 28: TOF radiologic findings

Remember:

Volume overload leads to dilation Pressure overload leads to hypertrophy

RA prominence

RV

Dec. vascularity

Concave MPAOverriding aorta


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V. VALVULAR HEART DISEASES May be congenital or acquired

Pathophysiology and clinical manifestations similar in bothAlmost all acquired valvular heart diseases are rheumatic in

origin

MITRAL VALVE STENOSIS (MITRAL STENOSIS)

Figure 29: Mitral valve stenosis.

Narrowing of the mitral valve, so it cannot open properly Blood flow to the left ventricle (and to the systemic circulation) is

obstructed

Radiologic findings:Normal to slightly enlarged heartChamber prominence: LA (due to pressure build-up), RV

(pulmonary vasculature congestion)

Equalization or cephalization of pulmonary blood flowProminent main pulmonary artery segmentSmall aortaRA wont be affected unless tricuspid valve has a problem

Figure 30: Mitral stenosis (PA view)

Figure 31: Mitral stenosis (lateral view)

Ria: Nakakapagod mag-aral. Mas gusto ko mag-edit ng trans, k. Dear USERS,

kung mabasa niyo to, kung ako maka Top 10 na score sa exam na to alam

niyo na. Hahahaha!

Prominent LA

equalization

Prominent MPA

Prominent RV

Prominent RV

Prominent LA

20100913 os205 cardiac imaging

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