Acquired Valvular Diseases of the heart

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Acquired Valvular Diseases of the heart different imaging techniques

Transcript of Acquired Valvular Diseases of the heart

Muscular organ that pumps blood

throughout the circulatory system.

Situated between two lungs in the

mediastinum

4 chambers – 2 atria / 2

ventricles

Right and Left atria are

separated from one another

by a fibrous septum

Interatrial Septum

Right and Left ventricles- by

Interventricular Septum

Upper part – memberanous

Lower part - Muscular

4 Valves

2 Atrioventricular Valves

Mitral and Tricuspid

between Atria and Ventricles

2 Semilunar Valves

Aortic and Pulmonary

placed at opening of blood vessels arising from ventricles

Left AV valveMitral Valve or Biscuspid Valve

Right AV valveTricuspid Valvehas 3cusps (anterior, superior,inferior)

Composed of

saddle-shaped fibrous annulus

2 leaflets (a semicircular anterior leaflet and a rectangular posterior leaflet)

2 commissures

2 papillary muscles (anterolateral and posteromedial)

chordae tendineae, which are fibrous tendons

that arise from the papillary muscles and insert on

the free edges of the leaflets

Half moon shaped

Made up of 3 flaps

Aortic Valve and

Pulmonary Valve

Open only towards aorta

and pulmonary artery and

prevent backflow of blood

into the ventricles.

is composed of a fibrous annulus,

3 cusps (right coronary cusp, left coronary

cusp, posterior or non-coronary cusp)

3 commissures that separate the cusps

fibrous annulus,

3 cusps

3 commissures separating the cusps.

Inspection – Apical impulse/pulsations

Palpation-apical impulse/thrills/palpable

heart sounds

Percussion-asses cardiac borders

Auscultation - murmurs

Plain Chest X Ray

Fluroscopy

2D Echocardiograpy

CT Scan

MRI

Radionuclide Imaging

Angiography

Teleroentgenogram

6 feet distance

Shoulders rotated forwards and downwards

Centering T7 verterbrae

High KvP technique

Left Atrium

Left Ventricle

Right Ventricle

Aorta

Main pulmonary artery

Inferior Vena Cava

Cardiac apex

Cardia - Site/Shape/Size/Borders

Enlargement of chambers

Aortic arch/pulmonary art

Pulmonary vascularity

Shift of Mediastinum

Diaphragm – level/tenting/flattening

CP Angles

CardioThoracic Ratio:Internal diameter of the thoracic

cavity from the Medial border of

the ribs at the level of Right

hemidiaphragm

Transverse cardiac measurement

as the horizontal distance the

most Lateral aspects of the left

and right margins of the heart

Normal CT Ratio Adults – 50%

Newborns - 57%

Infants – 55 %

Pure stenosis or Regurgitation or Both

Dilated aortic shadows

Aortic stenosis

Aortic Regurgitation

HTN

Coaractation of aorta

Aneurism of aorta

Dilated Pulmonaryartery

Pulmonary stenosis

PA HTN

idiopathic

Double density

Enlargement of LA

appendage

Upliftment of left

mainstem bronchus

Widening of carinal

angle

Lateral view:

Prominent

posterosuperior

cardiac border

Posterior

displacement and

upliftment of left

mainstem

bronchus

Usually subtle and difficult to determine in mild and moderate cases

Lateral prominence of right heart border often associated with increase in convexity

In severe chronic cases right heart border can become massively distended towards right side

The ventricle enlarges

towards the lateral

wall of the thorax in a

downward direction,

displacing the apex

laterally and inferiorly

Lateral View:

posterior displacement of the posterior inferior border of the heart

Hoffman-Rigler Sign: measured 2 cm above the intersection of the diaphragm & IVC;

(+) if posterior border extends more than 1.8 cm of IVC

Rounding and

upliftment of cardiac apex

Lateral view

Retrosternalfullness

contact of anterior

cardiac border

greater than 1/3 of

the sternal length

Volume Overload Pressure Overload

Right Atrium Tricuspid

Regurgitation

Tricuspid Stenosis

Left Atrium Mitral Regurgitation Mitral Stenosis

Right Ventricle Tricuspid

Regurgitation

Pulmonary

Regurgitation

Pulmonary Stenosis

Left Ventricle Mitral Regurgitation Aortic Stenosis

Levocardia:

the heart is predominantly in the left chest, and the cadiac apex points leftward

Dextrocardia:

the heart is predominantly in the right chest, and the cardiac apex points rightward

Mesocardia:

the heart is positioned in the midline, and the cardiac apex points directly inferiorly

Dextroposition (dextroversion):

the cardiac apex points leftward, but the heart is located predominantly in the right chest (typically due to extrinsic forces)

“SITUS” - pattern of anatomic arrangement.

atrial situs is usually concordant with

visceral situs (stomach on left, liver on

right); hence these two are described

together

Situs solitus:

the morphologic right atrium is to the right

of the morphologic left atrium

the gastric air bubble is on the left side, and

the liver is on the right

Situs inversus:

the morphologic right atrium is to the left of

the morphologic left atrium

the gastric air bubble is on the right side,

and the liver is on the left

Situs ambiguous:

this term is used when identification of

visceroatrial situs is not possible due to

paucity of anatomic markers

Normal ArborizationPattern

• tapering from medial to

lateral

• outer 1 cm of lungs has no

markings

• tapering from bottom to up

• preferential flow to lung

bases

• increase in caliber of vessels

inferiorly

• Blood vessel accompanying

bronchi should be 1:1

Increase in perfusion may be seen as an increase in the calibre of the blood vessels

Decrease in perfusion is seen as darker lungs and very few appreciable vessels

Pulmonary Oligemia

• Vascular shadows reduced

• Occurs in TOF

• pulmonary artery HTN

• Critical Pulmonary Stenosis with reversal of

shunt

Pulmonary Plethora

• Vascular shadows are numerous

• Seen in lateral 1/3 rd of lung fields

• End on vessels are more in no (>5)

• Left atrial or right atrial enlargement usually

Pulmonary Venous hypertension• in PVH equalization of vascualrity

>12mm Hg – upper lobe veins=lower lobe Cephalization

upper lobe veins more prominent

>15mm Hg – Kerley B lines(lateral,septal)

Kerley A lines(longer,linearreaching hilum)

>25mm Hg – frank alveolar edema

Seen in Mitral Valve disease

• Perihilar haziness

• Bronchial cuffing (signet ring and thick outline)

• Redistribution of blood flow

Pulmonary EdemaPulmonary venous pressure > 25-28mm Hg

Typical Batwing appearance seen

Seen in Mitral valve diseases

AORTIC STENOSIS

Causes:

• Calcification of Congenitally deformed bicuspid valve in Men > 30yrs

• Degenerative calcific disease in middle aged/elderly patients

• Rheumatic Heart Disease

• Degeneration of a normal trileaflet aortic valve

Calcification of valve usually indicates gradient across valve of > 50mm Hg

Symptoms

Chest pain/shortness of breath/syncope

Mechanism

Deposition of Calcium on aortic cusps obstruct the outflow by their bulk as well as by stiffening of cusps – Stenosis

Area (cm2 ) Mean Gradient(mm Hg)

NORMAL 3 Few

Mild 1.5-2 <25

Moderate 1-1.5 25-40

Severe 0.6-1.0 >40

Critical <0.6 >70

Normal-sized heart or mild cardiomegaly

Left ventricular hypertrophy (muscular)

+/- pulmonary venous hypertension

Dilated ascending aorta only (the rest of the

aorta normal) due to jet of blood from

stenosis

+/- calcification

Calcification of aortic valve

Thickening

Increased echogenecity

Reduced mobility of the valve leaflets

Acoustic shadowing behind the calcification

Coronal

gradient-echo

MRI image

Calcification of

aortic valve

produces a

signal void

Causes

Damage to valvular cusps

• Rheumatic heart disease

• Endocarditis

• Marfan’s syndrome – dilatation of aortic root

• Syphilis

• Luetic aortitis

• Aortic dissection

• Connective tissue diseases

Volume overload on LV

Cardiomegaly

Left ventricular enlargement

Dilated ascending aorta and aortic arch due to large blood volume

Normal pulmonary vascularity

Sitting Dove sign

Color Doppler – jet of regurgitation

Continuous wave doppler interrogation of

the regurgitant jet in LV

Pulse wave doppler sampling of flow in

aortic arch to detect any abnormal reversal

flow

Doppler images taken in the parasternal long-axis view.

(A) A very small central regurgitant jet indicating mild aortic regurgitation.

(B) (B) A much broader based jet in a patient with severe aortic regurgitation

MITRAL STENOSIS

Cause: Rheumatic fever

Multiple episodes of

Acute Rheumatic Fever

causes PanCarditis

Other causes: (Rare) congenital anomalies,

prior exposure to chest radiation,

mucopolysaccharidosis,

severe mitral annular calcification,

left atrial myxoma

Infective endocarditis

Carcinoid syndrome

Fabray’s Disease

Hurler’s syndrome

Whipple’s Disease

• Fusion of the leaflet commisure

• Shortening and thickening of chorda

tendinae

Reduction of flow

Mitral stenosis occurs

•Left atrial pressure ↑

•Left atrium enlarges

•Cephalization

•Pulmonary Interstitial Edema

•Pulmonary Artery Hypertension develops

•Pulmonary Vascular Resistance increases

•Right Ventricle enlarges

•Pulmonic regurgitation develops

•Tricuspid annulus dilates

•Tricuspid insufficiency

•RV failure

Effect of MS on Lungs

Pulmonary arterial hypertension develops

muscular hypertrophy and hyperplasia

increased pulmonary vascular resistance

Chronic edema of alveolar walls -> fibrosis

Pulmonary hemosiderin deposited in lungs

Pulmonary ossification may occur

Area (cm2 ) Mean Gradient(mm Hg)

NORMAL 4-6 Few

Mild >1.5 <5

Moderate 1-1.5 5-10

Severe <1.0 >10

Enlargement of left

atrial appendage

Early – normal heart

size and subtle signs

of left atrial

enlargement

Straightening of

left heart border

Small aortic knob

Double density of

left atrial

enlargement

Severe and longstanding cases – calcification

of the valve

Cephalization

Elevation of

main stem

bronchus

Widened carinal

angle

Leaflet thickening or

calcification (hockey-stick deformity of the mitral valve

leaflets is typical)

leaflet mobility

commissural or

sub-valvular fusion

Echocardiography (parasternal

long axis) shows marked thickening of

mitral leaflets with restricted mitral valve

orifice (doming anterior leaflet). Left atrial

(LA) enlargement is evident.

MITRAL REGURGITATION

Degenerative valve or chordal tissue Prolapsed leaflet

Ruptured chordae

Myxomatous degeneration

Secondary to ischaemic heart disease or cardiomyopathyDilated mitral annulus

Papillary muscle dysfunction

Papillary muscle rupture

Rheumatic mitral disease

Infective endocarditis

Hypertrophic cardiomyopathy

In acute MRAcute Pulmonary edema

Heart is not enlarged

In chronic MR-LA and LV are markedly enlarged

Volume overload

-Pulmonary vasculature is usually normal

LA volume but not pressure is elevated

In Marfan’s SyndromeEnlargement of aortic root

Acute non-rheumatic mitral regurgitation. (A) Frontal view in the acute phase.

Heart size – nomral

even in the presence of high left atrialpressure as evidenced by the preferential dilatation of the upper-lobe vessels and interstitial oedema

The acute lesion of rheumatic fever is mitral

regurgitation, not stenosis

The largest left atria ever are produced by mitral regurgitation, not mitral stenosis

2D Echo – morphological abnormality

Doppler – assessment of regurgitation

Prolapse of posterior leaflet- regurgitation

jet will be directed superiorly to the roof of

the left atrium near aortic root

Proplapse of anterior leaflet – jet will be

directed inferiorly

TransoesophagealEchocardiography

Assess exact nature

and severity of the

lesion

Shows evidence of regurgitation secondary to lesions of right heart or pulmonary Hypertension

Causes:

Bacterial Endocarditis -Staphlycoccal

Late feature of Rheumatic Heart Disease

Metastatic carcinoid Disease

Normal area – 10.5 cm2 Mean gradient – 40-45mmHg

Enlargement of Right atrium

Prominent bulging or elongated right

heart border

+/- SVC or IVC prominence

Tricuspid stenosis. (A) The right heart border has bulged to

the right and its radius of curvature has increased.

(B) In the lateral view, the gap

between the front of the heart

and the sternum is filled in.

Commonly aortic and mitral valves

2Types – Mechanical / Biological

Mechanical

~Ball and cage type(rare)

~Tilting disc type

Single – Bjork-Shiley

Bileaflet- St Jude or carbomedic

Biological

Stentmounted porcine xenografts

(pig valve tissue mounted on a frame)

or homograft valves (human tissue, usually without additional mechanical support)

Visible on Echocardiography

Small orifice size than the original valve

Doppler – slightly restrictive pattern

Structure FractureStructure fractures have been reported

in some types of mechanical valves;

CXR using microfocus,

Fluoroscopy and CT have been useful

in identifying fractures

Porcine BioprosthesisThe major problem with porcine bioprostheses

is their poor durability.

5th post of year - Cusp tears, degeneration,

perforation,fibrosis and calcification appear

10th year 20% will fail and require

reimplantation

Incidence - 0.9 to 4.4%,

most frequent - within 6 months of valve

replacement

Organisms – Streptococcus, Staph aureus,

Candida albicans

Transoesophageal Echocardiography

Vegetations

Small(1-5mm) very large(2-3cm)

Damaging free edge of leaflets or leaflet

perforation ->Valve regurgitation

Abscess formation

Transoesophageal echocardiogram in the long-axis plane. The bicuspid aortic valve shows large

vegetations on opposing leaflets (A)

(arrow).

The shortaxis view confirms the bicuspid

anatomy and shows the

'kissing' vegetations on

opposing leaflets (B) (arrow).

Helps in assessing post-op complications

MRI is limited in vegetation detection

because of the artefacts generated by

ferromagnetic components

useful for assessing pseudoaneurysms

produces a set of

images at different

stages of the cardiac

cycle that can be

viewed dynamically

Any marked

turbulence of flow of

blood is

demonstrated as

black signal voidAt the level of aortic valve in pt with

aortic valve stenosis

Acquired is Very Rare

May be due to Carcinoid Disease and

Endocarditis