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Congenital Heart DiseaseCongenital Heart Disease
Conrad Cheung, MDMarie Sankaran, MD
Department of AnesthesiologyBoston University Medical Center
Faculty Advisor: Elena Brasoveanu, MDMarch 9, 2006
Classification Classification Acyanotic
– Interrupted Aortic Arch– Aortic Stenosis– Ventricular Septal Defect– Atrial Septal Defect
Cyanotic Defects– Hypoplastic Ventricle– Pulmonary Stenosis– Tetralogy of Fallot– D transposition of the great vessels– Tricuspid atresia
PlanPlan
We will discuss few topics that are important from the anesthesiologist point of view– Septal Defects– Atrial Septal Defects– Patent Ductus Arteriosus– Interrupted Aortic Arch– Tetralogy of Fallot– Single ventricle
The Cyanotic NeonateThe Cyanotic Neonate Ductus Arteriosus closes within 6 hours of birth so
any congenital heart disease that relies on it for perfusion of oxygenated blood will present early
To prevent death from inadequate oxygenation, the duct has to be maintained open with prostaglandines
Any neonate with a congenital heart disorder that relies on an open ductus arteriosus for oxygenation will deteriorate rapidly and requires immediate transfer to a specialty center
Ventricular Septal Defect IVentricular Septal Defect I
Defect in the septum separating the left and right ventricles
Most common type of congenital heart disease accounting for 21% of all cases
Can occur singly or in multiples anywhere along the ventricular septum
Small defects often close spontaneously in the first 2 years of life while large defects require surgical repair within the 1st year
Ventricular Septal Defect IIVentricular Septal Defect II
Prevalence equal between boys and girlsDue to increased pressures in the left
ventricle, left to right shunting of oxygenated blood occurs
With the increased pulmonary blood flow, pulmonary hypertension can occur with large defects
Ventricular Septal Defect IIIVentricular Septal Defect III
Symptoms of Ventricular Septal Symptoms of Ventricular Septal DefectsDefects
Rapid breathingIrritabilityExcessive SweatingPoor weight gainCongestive Heart Failure, usually within 6
to 8 weeks of life if defect is largePulmonary Hypertension if defect is large
Treatments for Ventricular Septal Treatments for Ventricular Septal DefectsDefects
Lasix and Aldactone to decrease symptoms of CHF
Digoxin to increase effectiveness of myocardial function
If surgery needed, patching or suturing the defect can be done
Mortality from surgery is low
Atrial Septal Defect IAtrial Septal Defect I
Defect in the septum separating the left and right atria
Accounts for 5-10% of congenital heart disease
Twice as frequent in girls versus boysThree types of atrial septal defects
Atrial Septal Defect IIAtrial Septal Defect II
Ostium Primum: Defect located in the lower part of septum near tricuspid valve which separates the right atrium and right ventricle
Ostium Secundum: Defect located near center of atria septum (most common accounting for 50-70% of atrial defect)
Sinus Venosus: Located near the SVC or IVC’s entrances to the heart
Atrial Septal Defect IIIAtrial Septal Defect III
Atrial Septal Defect IVAtrial Septal Defect IV
Due to increased pressures, there is left to right shunting of oxygenated blood
If large defect, can cause enlarged right atria, right ventricle, and pulmonary artery resulting in abnormal arrhythmias
CHF can occur if left untreated till adulthood
Symptoms of Atrial Septal DefectsSymptoms of Atrial Septal Defects
Slender buildHeart murmur resulting from increased
blood flow through pulmonary valveUsually no significant exercise restriction
unless defect is large. SOB or palpitations are possible.
Treatment of Atrial Septal DefectsTreatment of Atrial Septal Defects
If defect is small (less than 2mm), will usually resolves spontaneously
If defect is large, surgical correction is needed
Minimally invasive procedures availableTranscatheter devices, such as a septal
occluder may be used
Patent Ductus ArteriosusPatent Ductus Arteriosus
The ductus arteriosus connects the pulmonary artery to the descending aorta during fetal life.
PDA results when the ductus fails to close after birth.
Picture: www.lpch.org
Patent Ductus ArteriosusPatent Ductus Arteriosus
Pathophysiology:– Blood flows from aorta to the
pulmonary artery, creating a left to right shunt, resulting in left atrium and ventricle overload.
– Increased pulmonary blood flow can result in pulmonary hypertension and reversal of the shunt, which is known as Eisenmenger’s Syndrome. This results in flow of desaturated blood to the lower extremities.
Picture: www.lpch.org
Patent Ductus ArteriosusPatent Ductus ArteriosusSymptoms:
– Children with small patent ductus are usually asymptomatic.
– Large left to right shunts develop symptoms of congestive heart failure such as tachypnea, tachycardia, poor feeding and slow growth
Physical exam:– Continuous murmur heard best at the left sternal
border.
Patent Ductus ArteriosusPatent Ductus ArteriosusLab Studies:
– CXR: enlarged cardiac silhouette secondary to left atrial and ventricular enlargement with prominent pulmonary vascular markings.
– EKG: left atrial enlargement, LVH– ECHO: doppler flow through the ductus
Treatment: – Surgical division or ligation of the PDA
Patent Ductus ArteriosusPatent Ductus Arteriosus
Anesthetic Management:
-Maintain high arterial pressures as low diastolic pressure and pulmonary steal can result in decreased organ perfusion.
Concerns After Repair:– Rarely, recanalization or incomplete ligation of the
ductus occur.– Post repair, these patients can be treated as healthy
patients and do not require endocarditis prophylaxis.
Interrupted Aortic Arch IInterrupted Aortic Arch I
Relatively rare occurs in 2 cases per 100,000 live births
Consists of 2 different defects: divided aortic arch and ventricular septal defect
Divided Aortic arch results in continued blood flow to the upper extremities, but none to the lower extremities
Interrupted Aortic Arch IIInterrupted Aortic Arch II
Lower extremities oxygenated due to the combination of patent ductus arteriosus and ventricular septal defect
PDA connects lower portion of the aortic to the pulmonary artery
VSD allows travel of oxygenated blood to the right ventricle which in turns travels to the pulmonary artery.
Interrupted Aortic Arch IIIInterrupted Aortic Arch III
Symptoms of Interrupted Aortic Arch ISymptoms of Interrupted Aortic Arch I
Often discovered 3-4 days after birth when the patent ductus arteriosus closes
Symptoms of shock develops very rapidly as no oxygenated blood flows to the lower extremities
Rapid breathing, clammy sweating, and poor feeding often develops during the first week
Symptoms of Interrupted Aortic Arch IISymptoms of Interrupted Aortic Arch II
Most babies born at term with normal length and weight
Heart murmur usually heardLiver may be enlargedLeft arm/leg pulses may be diminished or
absentEchocardiogram for diagnosis
Treatment of Interrupted Aortic ArchTreatment of Interrupted Aortic Arch
Before surgery, try to keep the PDA open to provide oxygenated blood to the lower extremities
Surgery to suture together the two ends of the aorta, patch the VSD, and ligate the PDA
85-90% patients survive the hospital stay
Long Term Prospects for Interrupted Long Term Prospects for Interrupted Aortic ArchAortic Arch
Patients are at increased risk for subacute bacterial endocarditis requiring antibiotics before surgery and dental work
Restriction from vigorous or competitive sports. Emphasis placed on child to self-limit their level of exertion
Tetralogy of FallotTetralogy of Fallot
Anatomic Defects– Ventricular septal
defect– Overriding Aorta – Pulmonary artery
stenosis– Right ventricular
hypertrophy
Picture: www.lpch.org
Tetralogy of FallotTetralogy of FallotPathophysiology:Increased resistance by the
pulmonary stenosis causes deoxygenated systemic venous return to be diverted from RV, through VSD to the overriding aorta and systemic circulation systemic hypoxemia and cyanosis
Picture: www.lpch.org
Tetralogy of FallotTetralogy of Fallot
Symptoms:– Dyspnea on exertion or when crying– Tet spells: irritability, cyanosis, hyperventilation
and sometimes syncope or convulsions due to cerebral hypoxemia.
– Patients learn to alleviate symptoms by squatting which increases systemic resistance and decreases the right-to-left shunt and directs more blood to the pulmonary circulation.
Tetralogy of FallotTetralogy of Fallot
Physical exam:– Clubbing of the fingers and toes– Systolic ejection murmur heard at the upper left sternal
border created by turbulent blood flow through stenotic RV outflow tract
Lab Studies:– CXR: prominent RV– EKG: RVH, right axis deviation– ECHO: displays and quantifies extent of RV outflow
tract obstruction
Tetralogy of FallotTetralogy of Fallot Treatment:
– Surgical closure of the VSD and enlargement of the pulmonary outflow tract
Anesthetic Management:-The goal is to control the magnitude of the right to left intracardiac shunt,
which is increased by: 1) Decreased SVR2) Increased PVR3) Increased myocardial contractility
-Patient given beta blockers for prophylaxis against Tet spells-Inhalation induction can be employed in an attempt to avoid Tet spells
while placing an intravenous line.-Physiologic monitoring includes standard ASA monitors and an arterial
line. Echocardiography and EEG may also be employed.
Tetralogy of FallotTetralogy of Fallot
Concerns After Surgical Repair:– Endocarditis prophylaxis– Residual VSD secondary to incomplete closure– Residual RV outflow tract obstruction– Chronic pulmonary valve regurgitation results in a large volume load
on the right ventricle that can lead to cardiomegaly and increased incidence of arrhythmias.
– Right ventriculotomy during the repair leads to scarring which increases the risk of dysrhythmias and conduction abnormalities.
Overall incidence of sudden death in TOF patients after surgical repair is about 0.3%.
Single Ventricle PhysiologySingle Ventricle Physiology
Group of congenital heart diseaseInstead of 2 separate ventricles, there is
essentially 1 ventricle pumping blood to the aortic and pulmonary artery
Complete mixing of oxygenated and deoxygenated blood occurs
Examples of Single Ventricle Examples of Single Ventricle Congenital ProcessesCongenital Processes
Tricuspid atresia: Narrowed pulmonary arteries. At Birth patent PDA allows sufficient oxygenation to occur, however after closure of PDA cyanosis results
Hypoplastic Left heart: Blood flow to the body severely restricted. Once PDA close, patient has profound shock
Tricuspid AtresiaTricuspid Atresia
Hypoplastic Left HeartHypoplastic Left Heart
Treatment of Tricuspid AtresiaTreatment of Tricuspid Atresia
Blalock-Taussig shunt placed to form a conduit between pulmonary artery and aorta to maintain oxygenation
Prior to surgery, maintain PDA patency
Treatment of Hypoplastic Left HeartTreatment of Hypoplastic Left Heart
Keep PDA patent prior to procedure to prevent patient from going into shock
Aorta is formed from the base of the pulmonary artery and narrowed aorta
Modified Blalock-Taussig shunt formed to maintain adequate oxygenation
Long Term outlook of Single VentricleLong Term outlook of Single Ventricle
Activity limitationsProphylactic antibiotics prior to surgery and
dental workLife-long checkups and medicationsProne to rhythm disturbances, fluid
retention, and increased risk of CHF
Anesthetic Considerations for Non-Cardiac Anesthetic Considerations for Non-Cardiac Surgery in Patients with Congential Heart Surgery in Patients with Congential Heart
DiseaseDisease
Has the heart defect been corrected?If so, what kind of follow-up has the patient
had?Should the surgery be done at a specialized
center with expertise in congential heart disease?
Will a cardiology consult be needed to help plan the anesthetic management?
Anesthetic Considerations for Non-Cardiac Anesthetic Considerations for Non-Cardiac Surgery in Patients with Congential Heart Surgery in Patients with Congential Heart
Disease IIDisease II
Pre-op the patient as you would any other with special emphasis on the heart
What is the patient’s functional capacity?Any recent echos or EKGs?Patients with a history of ASD or VSD
repairs are prone to arrhythmias and endocarditis