congenital heart disease in adults. background 8/1000 live born births 32,000 cases/yr liveborn...

Congenital Heart Disease in Congenital Heart Disease in AdultsAdults

BackgroundBackground

8/1000 Live born births 32,000 cases/yr Liveborn prevalence lower than fetal prevalence

– Fetal echo

20% die within first year– 80% of first year survivors reach adulthood– Prevalence 800,000 adults in U.S.

Focus on Adult congenital heart disease

Atrial Septal DefectAtrial Septal Defect

One third of adult patients with CHDF:M=2:1Secundum (75%)Primum 15%Sinus Venosus 10%

ASDASD

ASDASD

ASDASD

ASDASDAssociated AbnormalitiesAssociated Abnormalities

MVPCleft Mitral Leaflet MR (Primum)Anomalous Pulmonary Venous Return

– Sinus Venosus

ASD PhysiologyASD Physiology

Increased flow L-R– High-low pressure

Increased Right sided blood flowDilation of RA, RV and PA

ASD Clinical PresentationASD Clinical Presentation No symptoms until third or fourth decades

of life despite pulmonary to systemic flow (Qp:Qs) of 1.5 or more

Over the years, the increased volume of blood usually causes right ventricular dilatation and failure

Fatigue or dyspnea on exertion Supraventricular arrhythmias Paradoxical embolism, or recurrent

pulmonary infections Death from RV failure or Arrhythmias in 40-

50’s if uncorrected

Physical ExamPhysical Exam

Right ventricular or pulmonary arterial impulse may be palpable.

Wide and fixed splitting of the second heart sound– Increased blood flow in PA

A systolic ejection murmur second left intercostal space (pulmonic)– usually so soft that it is mistaken for an

“innocent”flow murmur. Flow across the atrial septal defect itself

does not produce a murmur.

ASD EKGASD EKG Right-axis deviation Incomplete right bundle-branch block

– R’ > R in V1 Left-axis deviation occurs with ostium primum

defects– 1-deg AVB, “notched s wave II”

A junctional or low atrial rhythm (inverted P waves in the inferior leads) occurs with sinus venosus defects.

Normal sinus rhythm for the first three decades of life, after which atrial arrhythmias may appear.

Secundum EKGSecundum EKG

Primum EKGPrimum EKG

ASD CXRASD CXR

Prominent pulmonary arteries Peripheral pulmonary vascular

pattern– Small pulmonary arteries well visualized in

periphery

RAE/RVE when advanced

ASD CXRASD CXR

ASD EchoASD Echo

RAE/RVEDirect visualization of Primum and

Secundum defectsSinus venosus defects require TEEMicrobubbles to assist with diagnosis

ASD EchoASD Echo

ASD PrimumASD Primum

ASD TreatmentASD Treatment

Qp:Qs 1.5 or more should be closed to prevent right ventricular dysfunction

Not recommended if irreversible pulmonary hypertension

Prophylaxis against infective endocarditis not recommended repaired or unrepaired– Except for first 6 months after closure

Percutaneous ClosurePercutaneous Closure

VSDVSD

VSDVSD

Most common congenital cardiac abnormality in infants and children

M:F=1:1 25-40 percent close spontaneously by 2 y.o. 90 percent of those that eventually close do

so by age10 70% are membranous, 20% muscular 5% just below the aortic valve (undermining

the valve annulus and causing regurgitation),

VSD PhysiologyVSD Physiology

Initially left-to-right shunting predominates

Over time pulmonary vascular resistance increases and left-to-right shunting declines

Eventually the pulmonary vascular resistance exceeds the systemic resistance and right to left shunting begins

VSD ExamVSD Exam

With left-to-right shunting and no pulmonary hypertension– left ventricular impulse is dynamic and

laterally displaced– murmur is holosystolic, loudest at the lower

left sternal border usually accompanied by a palpable thrill

– A short mid-diastolic apical rumble (caused by increased flow through the mitral valve) may be heard

VSD ExamVSD Exam Small, muscular VSD may produce high

frequency systolic ejection murmurs that terminate before the end of systole – High pressure, small defect– defect is occluded by contracting heart muscle.

If pulmonary hypertension develops, RV heave and a pulsation over the pulmonary trunk may be palpated – Murmur and thrill eventually disappear as flow

through the defect decreases Cyanosis and clubbing are late findings

VSD EKGVSD EKG

Small defect-normal Large defect- left atrial and

ventricular enlargementIf pulmonary hypertension occurs

– QRS axis shifts to the right,– right atrial and ventricular

enlargement

VSD CXRVSD CXR

Small defect- normalLarge defect LAE, LVE, “Shunt

Vascularity”Pulmonary hypertension:

– proximal pulmonary arteries enlarged– rapid taperingof the peripheral

pulmonary arteries, and oligemic lung fields “Pruning”

VSD CXRVSD CXR

VSD EchoVSD Echo

Two-dimensional echocardiographyConfirm the presence and locationColor-flow mapping provides

information about the magnitude and direction of shunting

Qp:Qs

VSDVSD

VSD ManagementVSD Management

Small defects (Qp:Qs < 1.5)– No need for surgery– High Risk SBE, Prophylaxis provided

Large defects who survive to adulthood usually have left ventricular failure or pulmonary hypertension/ right ventricular failure– Surgical closure recommended

Once the ratio of pulmonary to systemic vascular resistance > 0.7 risk of surgery is prohibitive

PDAPDA

PDAPDA Connects descending aorta (just distal to the

left subclavian artery) to the left pulmonary artery

In the fetus, it permits pulmonary arterial blood to bypass lungs and enter the descending aorta for oxygenation in the placenta

10 percent of cases of congenital heart disease. – Perinatal hypoxemia – Maternal rubella– Infants born at high altitude or prematurely

PDA ExamPDA Exam

Bounding arterial pulses with widened pulse pressure

Hyperdynamic left ventricular impulse A continuous “machinery” murmur

– Second left anterior intercostal space – Peaks immediately after the second heart sound

(thereby obscuring it)– declines in intensity during diastole.

If pulmonary hypertension develops continuous murmur decreases in duration eventually disappears

PDA CXRPDA CXR

Left atrial and ventricular hypertrophy

Pulmonary plethora, proximal pulmonary arterial dilatation, RVH

Prominent ascending aorta May be visualized as an opacity at

the confluence of the descending aorta and the aortic knob

PDA CXRPDA CXR

PDA ImagingPDA Imaging

With two-dimensional echocardiography the ductus arteriosus can usually be visualized

Doppler studies demonstrate continuous flow in the pulmonary trunk

Quantify the magnitude of shunting

PDA EchoPDA Echo

PDA ManagementPDA Management Small defects

– No need for surgery– High Risk SBE (0.45 % annually after age 20) Prophylaxis

provided – Some recommend closure to prevent SBE

Large defects– Sx during childhood or adulthood: fatigue, dyspnea, or

palpitations– The ductus arteriosus may become aneurysmal and

calcified, which may lead to its rupture – Left ventricular failure from Vol overload– When pulmonary vascular resistance exceeds systemic

vascular resistance, the direction of shunting reverses (Cyanosis)

PDA SurgeryPDA Surgery

1/3 of patients not surgically repaired die of heart failure, pulmonary hypertension, or endarteritis by age 40 2/3 die by age 60

Surgical ligation or percutaneous closure accomplished without cardiopulmonary bypass

Mortality of less than 0.5 percent Once severe pulmonary vascular obstructive

disease develops closure is contraindicated.

CoarctationCoarctation

Coarctation PhysiologyCoarctation Physiology

A diaphragm-like ridge extending into aorta just distal to the left subclavian artery at the ligamentum arteriosum

Less commonly immediately proximal to the left subclavian artery– difference in arterial pressure is noted between the

arms Collateral circulation through the internal

thoracic, intercostal, subclavian, and scapular arteries develops

CoarctationCoarctation

M:F = 4-5:1 Associated abnormalities Gonadal dysgenesis (e.g.,Turner’s

syndrome) Bicuspid aortic valve (30%) Ventricular septal defect Patent ductus arteriosus Mitral stenosis or regurgitation Aneurysms of the circle of Willis

Coarctation PresentationCoarctation Presentation Most adults are asymptomatic Diagnosis is made during physical exam

– Systemic arterial hypertension observed in the arms, with diminished or absent femoral pulses

If symptoms are present, they are usually those of hypertension: headache, epistaxis, dizziness, and palpitations.

Occasionally, diminished blood flow to the legs causes claudication

May present with heart failure or aortic dissection Women with coarctation are at high risk for aortic

dissection during pregnancy

Coarctation Physical ExamCoarctation Physical Exam Systolic arterial pressure higher in the arms than

in the legs The femoral arterial pulses are weak and delayed A systolic thrill in the suprasternal notch A systolic ejection click (due to a bicuspid aortic

valve) A harsh systolic ejection murmur along the left

sternal border and in the back, particularly over the coarctation

A systolic murmur, caused by flow through collateral vessels, may be heard in the back

Coarctation CXRCoarctation CXR

Increased collateral flow through the intercostal arteries causes notching of the posterior third of the third through eighth ribs– Usually symmetric.

Notching is not seen in the anterior ribs – Anterior intercostal arteries are not located in costal

grooves The coarctation may be visible as an

indentation of the aorta with prestenotic and poststenotic dilatation of the aorta, producing the “reversed E” or “3” sign

CoarctationCoarctation

Coarctation ImagingCoarctation Imaging

The coarctation may be visualized echocardiographically

Doppler examination can estimate transcoarctation pressure gradient.

Computed tomography, magnetic resonance imaging, and contrast aortography– Location and length of the coarctation – Visualization of the collateral circulation– Measurement of Gradient on Cath

Coarct EchoCoarct Echo

Coarctation ComplicationsCoarctation Complications

Hypertension Left ventricular failure (2/3 of pts > 40 yo) Aortic dissection Premature coronary artery disease Infective endocarditis Cerebrovascular accidents (due to the

rupture of an intracerebral aneurysm) If uncorrected 3/4 die by the age of 50,

and 90% by the age of 60

Coarctation RepairCoarctation Repair

Repair considered for transcoarctation pressure gradient of more than 30 mm Hg

Balloon dilatation is a therapeutic alternative– Higher incidence of subsequent aortic aneurysm

and recurrent coarctation than surgical repair Postoperative complications include residual

or recurrent hypertension, recurrent coarctation, and the possible sequelae of a bicuspid aortic valve

Age at Time of RepairAge at Time of Repair

Surgery during childhood: – 90 percent are normotensive 5 years

later, 50 percent are normotensive 20 years later

– 89 percent of patients are alive 15 years later and 83 percent are alive 25 years later

Surgery after age 40: – Half have persistent hypertension– 15-year survival is only 50 percent

Bicuspid AoVBicuspid AoV

Aortic StenosisAortic Stenosis Supravalvular and Infravalvular Stenoses typically

present in childhood Bicuspid aortic valve 2 to 3 percent adult population. M:F=4:1 20% have associated cardiovascular abnormality

such as patent ductus arteriosus or aortic coarctation. Not stenotic at birth, subject to abnormal

hemodynamic stress, leads to thickening and calcification of the leaflets

Abnormality of the medial layer of the aorta above the Valve predisposes to dilatation of the aortic root

Aortic Stenosis PresentationAortic Stenosis Presentation

The classic symptoms are angina pectoris, syncope and heart failure

Adults with aortic stenosis who are asymptomatic have a normal life expectancy; they should receive antibiotic prophylaxis

Once symptoms appear, survival is limited: the median survival– five years after angina develops– three years after syncope occurs– two years after heart failure appears

Aortic Stenosis Physical ExamAortic Stenosis Physical Exam Carotid upstroke delayed and diminished

(parvus et tardus) The aortic component of S2 diminished or

inaudible Fourth heart sound is present A harsh systolic crescendo–decrescendo

murmur is audible over the aortic area and often radiates to the neck

As the aortic stenosis worsens, the murmur peaks progressively later in systole

Aortic Stenosis Work UpAortic Stenosis Work Up

Left ventricular hypertrophy is usually evident on EKG

Unless the left ventricle dilates, CXR demonstrates a normal cardiac silhouette

TTE with Doppler permits assessment of the severity of the stenosis and of left ventricular systolic function.

Cardiac catheterization is performed to determine the severity of aortic stenosis and to determine concomitant coronary artery disease.

Aortic Stenosis TreatmentAortic Stenosis Treatment

If mild, only SBE prophylaxisIf symptomatic, valve replacement

necessaryValve replacement prior to development of

LV dysfxn– Nl LV fxn– LVH will regress

Pulmonic StenosisPulmonic Stenosis

10 to 12 percent of congenital heart disease in adults.

Valvular in 90 percent of patients, remainder supravalvular or subvalvular

Supravalvular pulmonary stenosis in pulmonary trunk or branches– Often coexists with other congenital cardiac abnormalities

(valvular pulmonary stenosis, ASD, VSD, PDA, tetralogy of Fallot or Williams syndrome)

Subvalvular pulmonary stenosis caused by narrowing of the right ventricular infundibulum usually occurs in ventricular septal defect.

Pulmonary Stenosis Pulmonary Stenosis PhysiologyPhysiology

Typically is an isolated abnormality, may occur with VSD

Valve leaflets usually are thin and pliant; all three valve cusps are present

Commissures are fused– Valve is dome-shaped with a small central orifice – 10-15 percent have dysplastic thickened leaflets

2/3 of patients with Noonan’s syndrome have pulmonary stenosis due to valve dysplasia.

Pulmonic Stenosis DefinitionPulmonic Stenosis Definition Mild if the valve area >1.0 cm, transvalvular

gradient < 50 mm Hg, or peak right ventricular systolic pressure is <75 mm Hg

Moderate if the valve area is 0.5 to 1.0 cm, the transvalvular gradient is 50 to 80 mm Hg, or the right ventricular systolic pressure is 75 to 100 mm Hg.

Severe pulmonary stenosis is characterized by a valve area of less than 0.5 cm, a transvalvular gradient of > 80 mm Hg, or a right ventricular systolic pressure of more than 100 mm Hg

Pulmonic Stenosis Pulmonic Stenosis PresentationPresentation

If mild, usually Asx When the stenosis is severe, dyspnea on

exertion or fatigability may occur Less often may have chest pain or syncope with

exertion Eventually, right ventricular failure may develop,

with peripheral edema and abdominal swelling If the foramen ovale patent, shunting of blood

from the right to the left causing cyanosis and clubbing

Pulmonic Stenosis Physical Pulmonic Stenosis Physical ExamExam

With moderate or severe pulmonary stenosis: A right ventricular impulse at the left sternal border Thrill at the second left intercostal space Harsh crescendo–decrescendo systolic murmur

increases with inspiration at left sternal border If the valve is pliable, an ejection click often

precedes the murmur As the stenosis becomes more severe, the systolic

murmur peaks later in systole

Pumonic Stenosis CXRPumonic Stenosis CXR

Post-stenotic dilatation of the main pulmonary artery

Diminished pulmonary vascular markings

The cardiac silhouette is usually normal– An enlarged cardiac silhouette may be

seen if the patient has right ventricular failure or tricuspid regurgitation.

Pulmonic Stenosis EchoPulmonic Stenosis Echo

Right ventricular hypertrophy and paradoxical septal motion during

Site of obstruction can be visualized in most patients.

With the use of Doppler flow studies, the severity of stenosis can usually be assessed

Pulmonic Stenosis EchoPulmonic Stenosis Echo

Pulmonic Stenosis, TreatmentPulmonic Stenosis, Treatment

If mild only SBE Prophylaxis Survival 94 percent 20 years after diagnosis Severe stenosis should be relieved Moderate pulmonary stenosis have an

excellent prognosis with either medical or interventional therapy– Interventional therapy is usually recommended,

since most patients with moderate pulmonary stenosis eventually progress

Balloon ValvuloplastyBalloon Valvuloplasty

The procedure of choice High success rate provided the valve is

mobile and pliant Long-term results are excellent Secondary hypertrophic subpulmonary

stenosis regresses after successful intervention

Valve replacement is required if the leaflets are dysplastic or calcified or if marked regurgitation is present

Tetrology of FallotTetrology of FallotMost common cyanotic heart defect after

infancyOveriding aortaObstruction of RVOTRVHVSDAssociated with L-PA stenosis (40%), R

sided aortic Arch (25%), ASD (10%), Coronary Anomalies (10%)

Tetralogy of FallotTetralogy of Fallot

Tetralogy of FallotTetralogy of Fallot

Equal pressure in R and L ventriclesR-L shunting due to elevated RV pressures

from RVOT obstructionChanges in SV resistance affect shunting

– Increased SVR decreases R-L shunting

Tetralogy of FallotTetralogy of FallotPresentationPresentation

Cyanotic spells beginning in first year of life– Tachypnea, cyanosis– Can progress to LOC, Seizures, CVA, Death

Adults– Dyspnea and limited exercise tolerance– Complications of chronic cyanosis-

erythrocytosis, hyperviscosity, abnormalities of hemostasis, cerebral abscesses or stroke, and endocarditis.

Tetralogy of FallotTetralogy of FallotPhysical ExamPhysical Exam

Cyanosis and digital clubbing– Severity determined by the degree of RVOT

obstruction RV lift is palpable A Systolic ejection murmur caused by

turbulent flow across the RVOT (thrill may be may be palpable)– Intensity and duration inversely proportional to

severity of obstruction- flow shunted across VSD– a soft, short murmur suggests severe obstruction

Second heart sound is single, since its pulmonary component is inaudible

An aortic ejection click (due to a dilated, overriding aorta) may be heard

Tetralogy of FallotTetralogy of Fallot

EKG- right-axis deviation and right ventricular hypertrophy.

CXR- heart size is normal or small– lung markings are diminished. – “bootshaped,” heart– upturned right ventricular apex and

concave main pulmonary arterial segment.

– A right sided aortic arch may be present.

Tetrology of FallotTetrology of FallotCXRCXR

Tetralogy EKG Tetralogy EKG

Tetralogy of FallotTetralogy of FallotEchoEcho

Establishes diagnosisDetermines severity of RVOT obstructionFlow across VSDCardiac Cath

– Pressures, gradients, shunting, O2 sat, VSD– Origins of coronary arteries

Also seen by MRI or CTA

Tetralogy EchoTetralogy Echo

Tetralogy of FallotTetralogy of Fallot

Without surgical intervention, most patients die in childhood

Survival rate- 66 percent at 1 year of age, 40 percent at 3 years, 11 percent at 20 years, 6 percent at 30 years, and 3 percent at 40 years

Tetralogy of FallotTetralogy of FallotSurgical correctionSurgical correction

Relieves sx and improves survival Waterston: a side-to-side anastomosis of the

ascending aorta and the right pulmonary artery Potts: side-to-side anastomosis of the

descending aorta to the left pulmonary artery Blalock–Taussig: end-to-side anastomosis of

the subclavian artery to the pulmonary artery.– Long-term complications- pulmonary hypertension,

left ventricular volume overload, and distortionof the pulmonary arterial branches.

Blalock-TausigBlalock-Tausig

WaterstonWaterston

Tetralogy of FallotTetralogy of FallotSurgical correctionSurgical correction

Complete surgical correction– Closure of VSD– Relief of RVOT obstruction

Mortality 3% in children, 2.5-8% in AdultsRate of survival 32 years after

surgery 86% with repair vs. 96% in age-matched controls

Tetralogy of FallotTetralogy of FallotPost Surgical ComplicationsPost Surgical Complications

Ventricular arrhythmias detected with Holter monitoring in 40 to 50 percent

Moderate or severe pulmonary regurgitation

Systolic and diastolic ventricular dysfunction

Atrial fibrillation or flutter are common

Tetralogy of FallotTetralogy of FallotPost Surgical ComplicationsPost Surgical Complications

Pulmonary regurgitation may develop as a consequence of surgical repair of the RVOT– Can result in RVE and RV dysfunction– May require repair or replacement of the

pulmonary valve RVOT aneurysm may occur at site of repair

– Rupture has been reported Recurrent obstruction of RVOT may occur 10-20% have residual VSD CHB may occur AI is common but usually mild

EbsteinEbstein’’s Anomalys Anomaly

Downward displacement of septal leaflet of Tricuspid valve– Sometime posterior leaflet as well

“Atrialized Ventricle”Tricuspid regurg common80% have ASD or PFO

– Can result in R-L shunting

EbsteinEbstein’’s Anomalys Anomaly

EbsteinEbstein’’ss

EbsteinEbstein’’s Anomalys Anomaly Severity of defect depends upon degree of valvular

displacement Presentation ranges from severe HF in neonate to

incidental discovery in adults Neonates with severe disease have cyanosis, heart failure,

murmur noted in the first days of life– Worsens after the ductus arteriosus closes

Older children with Ebstein’s anomaly often come to medical attention because of an incidental murmur

Adolescents and adults present with a supraventricular arrhythmia.

EbsteinEbstein’’s Anomalys AnomalyPhysical ExamPhysical Exam

Severity of cyanosis depends on the magnitude of right-to-left shunting

Tricuspid regurgitation is usually present at the left lower sternal border.

Hepatomegaly from passive hepatic congestion due to elevated right atrial pressure may be present.

EbsteinEbstein’’s Anomalys AnomalyEKGEKG

Tall and Broad p-wavesRBBB1st degree AVB20% have ventricular pre-excitation

EbsteinEbstein’’s Anomalys AnomalyEKGEKG

EbsteinEbstein’’s Anomalys AnomalyCXRCXR

Normal in mild casesCardiomegally from RAEPulmonary markings decreased in severe

cases– Marked R-L shunting across ASD

EbsteinEbstein’’s Anomalys AnomalyTreatmentTreatment

Focuses on preventing and treating complications

SBE prophylaxisCHFRx of SVT

– RFA for accessory pathwayFontan procedure in severe cases

FontanFontan

EbsteinEbstein’’s Anomalys Anomaly

Tricuspid SurgeryRepair or replacementClosure of ASD/PFOPatient with severe sx despite medical RxCardiac enlargement

Transposition of the Great Transposition of the Great VesselsVessels

Aorta from RV, PA from LVComplete separation of pulmonic and

arterial saturationRequires communication between the

circuits for survivial– PDA, VSD, ASD or PFO

D-Transposition of the Great D-Transposition of the Great VesselsVessels

Transposition EchoTransposition Echo

Transposition of the Great Transposition of the Great Vessels Physical ExamVessels Physical Exam

Findings are nonspecific. Infants have cyanosis and tachypnea. The second heart sound is single and loud

(due to the anterior position of the aorta). In patients with mild cyanosis, a holosystolic

murmur caused by a ventricular septal defect may be heard.

A soft systolic ejection murmur (due to pulmonary stenosis, ejection into the anteriorly located aorta, or both) may be audible.

Transposition of the Great Transposition of the Great Vessels EKGVessels EKG

RADRVH- RV is systemic ventricleLVH- if VSD, PDA, Pulmonic Stenosis

present

Transposition of the Great Transposition of the Great Vessels CXRVessels CXR

Increased pulmonary vascularityEgg Shaped with a narrow stalk

Transposition CXRTransposition CXR

Transposition of the Great Transposition of the Great VesselsVessels

Mortality 90% by 6 months if uncorrectedInfusion of prostaglandin E (to

maintain or restore patency of the ductus arteriosus),

Creation of an atrial septal defect by means of balloon atrial septostomy (the Rashkind procedure).

Oxygen- to decrease PVR, increase pulmonary blood flow

Transposition of the Great Transposition of the Great Vessels-SurgeryVessels-Surgery

Atrial Switch- (Mustard)– Atrial septum excised and baffle created– Shunts blood to LV

RV continues to function as systemic ventricle– RV failure, SCD

Leakage of the atrial baffle (often clinically inconsequential)

Obstruction of the baffle (often insidious and frequently asymptomatic)

Sinus-node dysfunction Atrial arrhythmias, particularly atrial flutter

Atrial SwitchAtrial Switch

Arterial SwitchArterial Switch

Transposition of the Great Transposition of the Great Vessels-SurgeryVessels-Surgery

The atrial-switch operation has been replaced by the arterial-switch operation

Pulmonary artery and ascending aorta are transected above the semilunar valves

Coronary arteries switched, so that the aorta is connected to the neoaortic valve (formerly the pulmonary valve) arising from the left ventricle, and the pulmonary artery is connected.

This operation can be performed in neonates and is associated with a low operative mortality and an excellent long-term outcome.

Physiologic RepairPhysiologic Repair

Tetralogy of Fallot (TOF)

Senning's or Mustard's operation for transposition of the great arteries

Fontan operation for the single ventricle.

Approach to ManagementApproach to Management

Timetable of Congential Heart Timetable of Congential Heart SurgerySurgery

Congenital Heart Disease in Congenital Heart Disease in Adults Part IIAdults Part II

Cyanotic Heart DiseaseCyanotic Heart Disease

M.Ferguson CAPT, USN

NNMC

Palliative interventions increase or decrease pulmonary blood flow while allowing a mixed circulation and cyanosis to persist

Physiologic repair total or near total anatomic, physiologic, or both anatomic and physiologic separation of the pulmonary and systemic circulations.

Palliative OperationsPalliative Operations

Palliative OperationsPalliative Operations

Systemic arterial-to-pulmonary artery shunts – improvement in saturation levels – high levels of pulmonary blood flow– direct exposure of the pulmonary vascular bed to the

high pressures of the systemic circulation– long-term complications include pulmonary

hypertension, pulmonary artery stenosis, and volume overload of the ventricle receiving pulmonary venous return.

Cyanotic ConditionsCyanotic Conditions

Arterial O2 desaturation due to shutning of venous blood into arterial circulation (R-L)

Magnitude of shunting determines severity of desaturation