Cyanotic CHD Flashcards
(36 cards)
Which conditions present in the first 24 hours of life with cyanosis?
TGA
Single Ventricle
Mixing Lesions
Outflow tract obstruction
Which group of conditions present on Day 2+ with cyanosis?
Give examples of these conditions.
Lesions that are dependent on the PDA for pulmonary blood flow or mixing.
Pulmonary blood flow = Critical PS, Pulmonary atresia, single ventricle with either of those
Mixing = TGA, TAPVD, PS, pulmonary atresia, Ebstein’s anomaly
What are the physiological and pathological consequences of Cyanosis?
Polycythaemia Clubbing Vascular stroke Bleeding disorders/thrombocytopenia Scoliosis Hyperuricaemia and Gout
Which is the most common congenital heart defect in developed countries?
Is it more common in males or females?
In what ratio?
TGA
Male 3:1
What makes a TGA compatible with life?
What is the most desirable associated defect and why?
If there is an associated defect allowing communication between the two circuits eg PFO, ASD, VSD, PDA
Large ASD allows good mixing with less pressure overload than a VSD
What does the ECG show in TGA?
What does the CXR show?
ECG: RVH (upright T wave in V1) or BVH (if large VSD or PDA)
May be RAH
CXR: Cardiomegaly, increased pulmonary vascularity, egg shaped cardiac silhouette
What is the survival procedure to correct TGA?
When is it done?
Arterial switch operation.
Performed in the first few days of life.
What does the Echo show in TGA?
Double circles instead of circle and sausage.
What other lesion is always associated with truncus arteriosius?
Which other lesions are commonly associated?
Which syndrome is commonly associated?
What fraction of patients with Truncus have this syndrome?
Large VSD
Interrupted aortic arch and right sided aortic arch
DiGeorge syndrome - 1/3
How does Truncus Arteriosus usually present?
What is the clinical course if untreated?
Cyanosis at birth or in failure within the first few weeks.
CHF will progress and lead to death, or patients can develop Pulmonary Vascular Obstructive Disease.
How is Truncus Arteriosus surgically corrected?
Describe the procedure.
When is the procedure normally done?
Various versions of the Rastelli procedure.
- Seperate pulmonary arteries from truncus
- Connect RV to pulmonary arteries using a conduit
- Repair VSD
Performed within the first week of birth/presentation
Which conditions are included in the Single Ventricle spectrum?
Hypoplastic Left Heart Syndrome
Double-Outlet Right Ventricle
Doublet-Inlet Left Ventricle
Tricuspid Atresia (causes RV hypoplasia)
How many cases of single ventricle involve the Left heart?
Where does the second great artery arise from?
What is the most commonly associated defect with a single ventricle?
How often does this occur?
What other associated defects are common?
80%
A rudimentary chamber off the ventricle
Transposition of the Great Arteries, 85% of cases
Interrupted aortic arch, COA, anomalies of the AV valve
What determines saturations in single ventricle?
What are the consequences of a normal pulmonary valve?
Pulmonary blood flow, ie presence or absence of pulmonary stenosis, pulmonary atresia or pulmonary artery stenosis
Excess pulmonary blood flow with lead to congestive heart failure
What does the ECG show in single ventricle?
Abnormal Q waves
Ventricular hypertrophy pattern in all precordial leads
First or second degree AV block
What is the first stage of single ventricle repair?
When is it typically performed?
What is the second stage?
When is it typically performed?
If there is significant PBF - PA banding
If PBF is low, either Damus-Kaye-Stansel (patch between PA and Aorta) or BT shunt (between right subclavian and Right PA)
Performed in first few days of life
Second stage is Bidirectional Glenn, where SVC is plumbed directly into the pulmonary artery.
Typically done at 3-6 months
What is the third stage of repair for single ventricle?
When is it typically performed?
What complications can arise prior to stage 3?
Fontan procedure - connects IVC directly to PA
Typically done at 18-24 months
Complications: Thrombosis and shunt obstruction, arrhythmias, Chlyothorax, protein losing enteropathy
What at the complications of arterial switch surgery?
Coronary artery obstruction
Pulmonary stenosis
Neonaortic stenosis or regurgitation
What are the four classical defects seen in Tetralogy of Fallot?
What percentage of congenital heart disease does TOF make up?
In which direction does blood shunt through the VSD?
RV outflow obstruction (infundibular pulmonary stenosis), VSD with an overriding aorta and right ventricular hypertrophy
5-10%
Shunt depends on degree or RVOT obstruction:
If mild obstruction, shunt is L>R, patient is acyanotic
If severe obstruction, shunt if R>L, patient is cyanotic
Describe what you would hear when auscultating the heart in Tetralogy.
What would a long and loud murmur signify?
What would you see on an ECG of a patient with Tetralogy?
Heart Sounds: Ejection systolic murmur at ULSE, grade 3-5/6
Single S2, Ejection click in aortic area
Loud murmur means mild pulmonary stenosis
ECG: Right axis deviation, right ventricular hypertrophy
What causes a “Tet” spell?
What happens to the cardiac shunt? And the heart murmur?
What does that mean for pulmonary blood flow?
What are the possible consequences of a “Tet” spell?
Drop in systemic vascular resistance or increase in heart rate eg crying, activity, defaecation.
Cardiac shunt increases from R>L.
Murmur disappears or gets quieter because there is minimal blood flow through the pulmonary valve.
Pulmonary blood flow decreases hence the hypoxia.
Can cause stroke, seizures, death.
How do you treat a “Tet” spell?
How does each treatment help?
Squatting/Knee-chest position - Reduces systemic vascular return
Oxygen - Improve saturations
Morphine - Respiratory depression
Sodium bicarbonate- Corrects acidosis caused by poor perfusion
Vasoconstrictors eh phenylephrine - increases SVR
Ketamine - Sedation and increase SVR
How is Tetralogy treated medically?
How is it corrected surgically?
When is the procedure normally done?
Why might it be done earlier?
Propranolol can prevent “Tet” spells.
Important to treat iron deficiency.
May require a BT shunt initially if pulmonary atresia or hypoplastic pulmonary artery.
Full repair involves widening of RVOT and closure of VSD, usually done at 1-2y of age. Performed earlier if sats <75% or frequent spells.
What percentage of patients with TOF have Pulmonary Atresia?
Where does pulmonary blood supply come from if this is the case?
How will these patients present?
15-20%
Either PDA or collaterals
Present with cyanosis at birth, no murmur but loud single S2
