Congenital diagnosis and management Flashcards
Describe tricuspid atresia
Tricuspid valve never develops = no connection between RA and RV
Associated with ASD + large VSD + PDA
RV is hypoplastic (no flow no grow!)
Cyanotic
Describe circulation in tricuspid atresia
SVR enters RA, crosses ASD, mixes with PVR in LA, through MV (often hypoplastic) into LV
From LV, blood almost freely flows through VSD into hypoplastic RV
From the ‘common’ ventricles it can go to either (1) Aorta or (2) Pulmonary artery
Why is it ‘good’ to have PS in tricuspid atresia
We are ‘hoping’ for a concomitant degree of pulmonary stenosis, because pulmonary circulation is much lower resistance than systemic circulation, therefore if no PS there will be preferential blood flow into the pulmonary side
This worsens systemic perfusion and leads to pulmonary over-circulation, remodelling, and therefore pHTN.
Importantly, if pHTN develops, this would preclude Fontain palliation!!
On the other hand, if there is LV outflow tract obstruction this can also lead to systemic hypoperfusion and encourage preferential pulmonary circulation, similarly worsening the situation
Key management principles in tricuspid atresia
- Avoid too little systemic outflow
- Avoid pulmonary overcirculation
- Saturations and mixing of blood
Neonatal management of tricuspid atresia
Depends on principles of (1) managing the balance of pulmonary/systemic flow, and (2) managing O2 sats
- Maintain open duct - to improve pulmonary flow if there is excessive PS and therefore improve circulation to lungs
- Atrial septostomy - if no ASD, also to improve pulmonary flow if there is excessive PS and therefore improve circulation to lungs
- PA band - increase pulmonary vascular resistance and therefore essentially ‘create’ PS and avoid over-circulation to lung
Fontain Stage 1 timing and details
0-6 months
Norwood procedure
o Close PDA
o Create or widen ASD
o Create neo-aorta by re-rooting PV+proxPA into aorta - Damus-Kaye-Stansel (DSK) anastomosis
o Create new venous flow into PA with Blalock-Thomas-Taussig shunt (R SubC to PA) or Sano shunt (RV to PA)
End result of Stage 1 Fontan (Norwood procedure)
The heart pumps blood into one single common root
Blood flow to PA comes from a shunt from the aorta or RV
There is still atrial mixing
What are the BTT & Sano shunts
BTT - R SubC to PA
Sano - RV to PA
Fontan Stage 2 details
Bidirectional Glenn
o BTS/SanoS removed
o SVC cut above RA connection
o Connect SVC to PA directly
End result of Fontan Stage 2 (Bidirectional Glenn)
Blood flow to the lungs is now entirely via the SVC
There is still atrial mixing from IVC supply, but SpO2 improved
Fontan Stage 3 details
Usually at 2-5y
IVC connection to the pulmonary artery made
Extracardiac = SVC to PA, IVC to PA. RA is entirely bypassed
Total cavo-pulmonary conduit = connect SVC and IVC to PA; make a small fenestration in IVC to re-enter RA (to protect pulmonary circulation).
Close previous BT/Sano shunt
Classic Fontan risks
Massive RA dilation leading to significant atrial tachycardias; specifically intra-atrial re-entry tachycardia
High blood stasis leading to thrombus risk
In addition to normal Fontan, what did ‘Classic Fontan’ entail
Not done anymore
= connect RA to PA, and close ASD
List ASD types with %
- Secundum ASD (80%)
- Primum ASD (15%);
- Superior sinus venosus defect (5%)
- Inferior sinus venosus defect (<1%)
- Unroofed coronary sinus (<1%)
Shunting in ASD
ALL start as L>R shunt, with worsening RVF, these can reverse (R>L) = Eisenmenger’s
Secundum ASD
located in the region of the fossa ovalis and its surrounding (= patent foramen ovale)
Primum ASD
== atrioventricular septal defect (AVSD) with communication on the atrial level only. located near the crux, AV valves are typically malformed (total AV canal defect), resulting in various degrees of regurgitation.
Superior sinus venosus ASD
located near the superior vena cava (SVC) entry, associated with partial or complete connection of right pulmonary veins to SVC/RA`
Inferior sinus venosus ASD
located near the inferior vena cava (IVC) entry].
Unroofed coronary sinus ASD
separation from the left atrium (LA) can be partially or completely missing.
Typical history in ASD
- Often asymptomatic until adulthood
- Symptoms beyond 4th decade: exertional SOB, reduced functional capacity, RHF then cyanosis
Exam in ASD
- Ejection systolic murmur with fixed split S2 (inspiration and expiration)
- Cyanosis if shunt reversal
Investigation in ASD
Echo: quantify shunt volume and severity, size of ASD, TOE might be required for secundum defects (posterior) +/- CMRI
P Cath if suspicion of raised PAP +/- exercise testing if suspect PAH
o Can measure QpQs on cath using oximetry values using Fick principle
VO2 = (CaO2 - CvO2) * Q
Qp:Qs = (SatAorta-SatSVC)/(SatPulmonaryV- SatPulmonaryArt)
Management of ASD
- Optimize medical therapy
- If: RV overload or paradoxical embolism OR PAH, closure
- Eisenmenger’s is beyond possible closure – at that stage, closure of shunt will make patient sicker as it will further increase pulmonary pressures by closing the ‘outlet’ into the L side
- Patients who do not undergo closure have worse outcomes
Closure of ASD types
o Surgical closure if complex lesion / primum ASD or decompensated
o Device closure if secundum ASD with amenable morphology (needs to have good margins for closure device with 5mm buffer area around)
o If PAH present (PVR>1/3 SVR, PASP>1/2 SBP), needs to be carefully considered w/ ACHD/PH team
Five types of VSD
Classified based on location
- Type 1 = subaortic
- Type 2 = in membranous septum (perimembranous, paramembranous, conoventricular)
- Type 3 = inlet (often within AVSD)
- Type 4 = muscular (towards ventricular apex)
- Gerbode = left ventricular to right atrial communication due to absence of AV septum
Typical history in VSD in children
Asymptomatic or symptomatic depending on size and where.
Large VSDs might cause fatigue, sweaty in feeds, recurrent RTIs, CHF and failure to thrive.
Adult with VSD - typical history
With advancing age, the following problems might occur:
- Double chamber RV (mostly perimembranous, due to the jet lesion on RV endothelium)
- Prolapse of RCC of aortic valve leading to significant AR due to unstable septum
- Arrhythmias
- Late LV dysfunction, heart block or heart failure
- Endocarditis risk
Exam findings in VSD
Small defect: blood flowing through VSD results in loud harsh blowing high pitched pansystolic murmur. May be associated with parasternal thrill.
Large defect: parasternal heave due to RVH, systolic murmur softer. Additional diastolic murmur due to increased flow through the mitral valve.
Intensity of murmur inversely proportional to severity of the shunt. Harsh, holosystolic murmur
harsh blowing high pitched pansystolic murmur. May be associated with parasternal thrill.
Small VSD
R parasternal heave, soft systolic murmur
Large VSD
Investigations for VSD
Doppler with echo demonstrating flow across septum.
CXR may show cardiomegaly, prominent pulmonary vasculature
ECG may show RVH/LVH
VO2 testing
Rule of thumb re: which ventricle is strained by pre- vs post-tricuspid shunt
Pre-tricuspid shunt - LV primarily loaded - generally do not develop pHTN / RV failure
Post-tricuspid shunt - RV primarily loaded - greater risk of pHTN / RV failure
Pre-tricuspid shunt examples
ASD
Post-tricuspid shunt examples
AVSD
VSD
APW
PDA
Indications for intervention in VSD
o RCC prolapse
o PAH (PVR>3WU) – careful balance, if PAH severe might be too high risk for closure
o QpQs >1.5 or <1 (ratio of total pulmonary blood flow to total systemic blood flow, normal = 1, L:R shunt >1, whereas R>L shunt <1)
Anatomy in TAPVR
- The PV do not connect to the LA, but connect to the SVC (or IVC, or innominate)
- TAPVR HAS to be associated with ASD (most sinus venosus) - allows movement of blood in to LV
- Therefore blood flow IVC > RA > RV > PA > PV > RA > LA > Body (purple)
Blood flow in TAPVR
IVC > RA > RV > PA > PV > RA > LA > Body (purple)
Timing of surgery in TAPVR
Neonatal period
Spectrum of APVR
Can go anywhere from:
One single anomalous pulmonary vein return (e.g, into IVC, Scimitar syndrome), which leads to a degree of increased RV preload but usually does not require intervention
to
ALL pulmonary veins connect to right-sided circulation, which is a duct-dependent lesion and a cyanotic congenital heart disease requiring intervention in the neonatal period
Types of surgery in TAPVR
Overall principle is intracaval baffling of anomalous PV return back to LA
OR
direct reimplantation of anomalous PV to LA
What is a Warden procedure
For: sinus venosus ASD + TAPVR
Involves:
1. Transection of SVC above the origin of PV
2. Mouth of SVC redirected with intracardiac baffle through ASD to shuttle blood from PV through SVC base into LA
3. Upper SVC segment directly connected to RA
Describe a PDA
Persistent communication between the proximal left PA and the descending aorta just distal to the left subclavian artery.
Typical presentation of PDA in adults
In adults with no known ACHD, usually isolated finding
PDA originally results in L–R shunt and LV and LA volume overload
‘machinery-like’ murmur in late diastole and early systole, sounds like a steam train, ff-p-ff p. Loudest at LUSE.
PDA
PDA murmur
‘machinery-like’ murmur in late diastole and early systole, sounds like a steam train, ff-p-ff p. Loudest at LUSE.
Indications for intervention in PDA
- LV volume overload
- PAH (PVR>3WU) or large L>R shunt (QpQs >1.5)
Are pregnancy and sports ok in people with PDA
Unless LV overload or PAH, sports and pregnancy ok
Physiology behind duct open/closing
Fetal patency ensured by ductal production of PGE2 but this falls at birth and DA should close within 2 weeks.
Timing and types of closure
Normal closure at 15h, some have it after first breath (funcitonal closure, contraciton of SM).
True anatomical closure takes weeks (permanent closure, proliferation of fibroblasts).
Associations of PDA
Prematurity, perinatal distress, fluid therapy, hypoxia.
May have congenital rubella, chromosomal abnormality, fetal alcohol syndrome, maternal amphetamines, FHx.
History in PDA in child
- Small: asymptomatic
- Medium: low exercise tolerance, breathless, hoarse cry/cough as child, LRTI comon and alectasis/pneumonia.
- Large: symptoms of HF, dyspnea and failure to thrive. Neonatal aopnea/bradycardia.
Examination in PDA
- Premature: rough systolic murmur in left sternal border. Bounding pulses.
- Small: normal pulses, BP continuous machinery murmur and thrill below left clavicle (pressure gradient between aorta and pulmonary vessel.
- Medium: wide pulse pressure, bounding peripheral pulse, LRTI.
- Large: absent thrill, murmur in systole only as pressures of aorta and arteries are equal in diastole.
- CHF: tachycardia, tachypnoea, respiratory distress, displaced apex, cool periph.
Investigations in PDA
CXR: cardiomegaly, signs of HF
ECG: LVH
Doppler Echo: diagnostic to confirm patency
Management of PDA
Preterm: conservative if asymptomatic, monitor, fluid restrict, PGE2 inhibitor to encourage closure
Surgical ligation if symptomatic
In term children, minimal access closure in cathlab ~ >1yo
Potential long term risks of PDA
High risk of PDA associated endocarditis, preterm (IVH, bronchopulmonary dysplasia, CHF).
pHTN + Eisenmenger syndrome.
Emboli. Untreated mortality 20%, with closure minimal
Describe HLHS
Underdevelopment or complete absence of L side of the heart, with large ASD usually or other form of shunt
Managed neonatally using Fontan procedure (or modifications thereof)
What is the Fontan procedure useful for
broadly applicable to multiple congenital abnormalities characterised by malformation or lack of one or more chambers of the heart
Final circulation in Fontan (example in HLHS)
o Dexoygenated blood from body into SVC/IVS direct into P trunk (Passive flow)
o Through lungs
o Oxygenated blood returned from lungs to hypoplastic LA
o Flows through ASD into RA
o Into RV through TV
o RV pumps into aorta
Typical findings on examination of Fontan patient
RV heave
Mild non pulsatile JV distension
High JVP + Hepatomegaly -> think of Fontan obstruction or failure
Long term outcomes of Fontan: adolescence
Uneventful course in childhood and adolescence usually
Long term outcomes of Fontan: adulthood
progressive decline in exercise performance and heart failure, cyanosis, chronic venous insufficiency, and development of important arrhythmias, especially in patients with a classical Fontan operation
Long term outcomes of Fontan: arrhythmias
By 10 years after a Fontan operation, ∼20% of patients have supraventricular tachyarrhythmias (including typically IART and atrial flutter, but also AF and focal AT)
Especially high risk in ‘Classic’ (Right atrium to pulmonary artery) Fontan
Long-term outcomes of Fontan: abdominal
Liver disease: hepatic congestion and severe fibrosis, portal hypertension and risk of hepatocellular carcinoma
Protein losing enteropathy: diagnosed by low serum albumin and elevated α1-antitrypsin levels in the stool. Poor progrnosis
Plastic bronchitis and lymphatic dysfunction
Description of CoA
Narrowing of aorta which can occur as discrete stenosis or as a long, hypoplastic aortic (arch) segment
Typically, CoA is located in the area where the ductus arteriosus inserts, and only in rare cases occurs ectopically (ascending, descending, or abdominal aorta)
Defined by its relation to the ductus arterious.
Preductal, ductal or potductal.
CoA associated diseases
- BAV (up to 85%)
- Ascending aortic aneurysm
- SubAS, or SupraAS,
- (Supra)mitral valve stenosis (including parachute mitral valve),
- Shone complex (supravalvular mitral membrane, parachute mitral valve, muscular or membranous subvalvular aortic stenosis and coarctation of aorta)
- Turner syndrome and Williams–Beuren syndrome.
- Extracardiac vascular anomalies - anomalous origin of the right subclavian artery (in 4–5% of cases), collateral arterial circulation, and intracerebral aneurysms (in up to 10%)
Symptoms of CoA
Headache, nosebleeds, dizziness, tinnitus, shortness of breath, abdominal angina, claudication, and cold feet.
Signs of left heart failure
Intracranial haemorrhage (from associated berry aneurysm), IE, aortic rupture/dissection, premature coronary and cerebral artery disease, and associated heart defects
Aetiology of CoA
Failure of normal development of the left 4th and 6th aortic arches (6/40)
Related to Turner, rubella, VSD, PDA, hypoplastic left heart (HLH), interruption of AA.
Symptoms of CoA in children
Neonatal: in ductal/postductal forms, when ductus arteriosus closes, the sudden decrease in outflow leads to pressure build in the LV, leading to sudden LVF (dyspnea, pulmonary oedema etc).
Infant: symptoms depend on severity and collaterals. Preductal has good collaterals, postductal less. May be asymptomatic until adolescence if good collaterals.
Exam findings in CoA
Nodding type head movements with HR, delayed or absent femoral pulse, RR delay, difference in BP in both arms, (>20mmHg).
Loud S1 and narrow split S2, collateral flow/coarctation murmur.
Investigations in CoA`
CXR: cardiomegaly, increased pulmonary markings in LVF. Hypoplastic aortic knob with dilated poststenotic segment.
ECG may show LVH.
Doppler echocardiogram is diagnostic.
Management of CoA
Medical: infusion of PGE1 in neonates to maintain open DA. Palliate symptoms of LVF with fluid restriction and diuretics. Blood pressure control
Surgical: resection of the coarctation, end to end anastomosis or subclavian artery flap repair. 10% re-coarctation.
Balloon angioplasty: alternative to surgery
Mechanism of hypertension in CoA
CoA -> decreased systemic BP -> low blood flow to renal -> low perfusion pressure of tubule cells -> high renin production -> high aldosterone -> Na/H2o reabsorb -> HTN.
Prognosis in CoA
Hypertension if untreated. May cause aortic dissection, aneurysm, and CAD.
Untreated do not survive past 50 typically. With correction 20y survival 91%.
Indications for intervention in CoA
> 50% narrowing, peak gradient >20mmmHg, or arterial hypertension
Describe TGA
TGA is characterized by AV concordance and ventriculo-arterial discordance:
Ao from RV
PA from LV
Simple TGA
TGA is called simple in the absence of associated congenital anomalies (except PFO and PDA)
o Duct dependent!
Complex TGA
TGA is called complex in the presence of associated anomalies
o VSD (∼45%), LVOTO (∼25%), and CoA (∼5%).
ccTGA / l-TGA
Additionally ventricular switch (RV on L side, LV on R side)
Usually with dextrocardia (20%)
‘Congenitally corrected’ - do not need neonatal intervention, this is not cyanotic or duct dependent
Features of d-TGA
o Aorta is RIGHTward and ANTERIOR
o 5% ACHD
o More boys, infants of diabetic mother
o 50% have PFO+PDA only (simple); 50% true complex TGA
Key facts about associated lesions in complex TGA
5% significant LVOTO (‘subpulmonary’), 40% VSD
NB after switch, ‘subpulmonary’ LVOTO this will become true ‘subaortic’ LVOTO
If VSD, cyanosis better, HF worse
If no VSD, cyanosis worse, HF better
Outcomes in simple vs complex TGA
Long-term outcome of complex TGA is, regardless of the type of surgical repair, worse than that of simple TGA.
Progression of surgical procedures - 1970s
1970-90s: Mustard/Senning ‘atrial switch’ repairs, baffle venous blood from SVC/IVC through into LA and into LV -> to PA
Effectively leads to a subpulmonic LV and subaortic RV
Long term issues with RV failure, arrhythmias due to high RA preload
Progression of surgical procedures - 1990s
1990s - Arterial switch procedures - Switch of arterial trunks and coronary arteries across to match the right ventricle
Typical procedure for Complex TGA
Rastelli-type repair
Key ‘red flag’ history + exam findings in post-atrial repair TGA patient that hint complication
- Swollen head and neck: superior baffle obstruction
- Swollen legs/abdomen: inferior baffle obstruction
- ESM: subpulmonary outflow tract obstruction
- PSM (regurgitant): TR II to RV dilation
- AR from neo-aortic root filation
Management post-atrial switch
- Diuretics if RV overload
- No evidence for prognostic HF meds
- EP input for arrhythmias
- PAH management
- Difficult to benchmark progression / failure of subaortic RV ?? reference ranges for EF!
% dTGA post repair and Fontan who develop HF
- 22% of dTGA and 40% of Fontain
% HT in US due to CHD
Proportion of transplant for ACHD is growing, and between 2010-12 was 4% of HT
Study looking at likelihood of CHD patients receiving a transplant
- Melanie Averick J Heart Lung transpl – pt with ACHD less likely to receive a transplant even when divided by initial listing status
Study looking at on list survival of ACHD patients
- JACC 2016 – patients with ACHD who are listed at top urgency 1a are more likely to die or be delisted compared to on achd conterparts
Barriers to transplant in CHD population
policies, sensitization, mental health, size matching in young people, anatomical consideration
Study on outcomes of transplant for CHD vs non CHD
ACHD patients who are transplanted have worse early mortality compared to non-achd, but if stratified after 1 year, those with ACHD perform significantly better
More recent data has shown much closer survival – likely that in historical data there was significant bias due to delay in referral of patients (which remains an issue)
Key factors contributing to why ACHD transplant outcomes are better at high volume centres
o Anaesthetic considerations: poor tolerance to anaesthetics and fluid shifts
o Operative considerations: multiple sternotomies, anatomy
o Post-op mx considerations: restoration of ‘normal’ circulation can be associated with significant organ dysfunction e.g., kidney injury, abnormal LFTs, slow ventilation weans
o Regionalisation can help improve outcomes
Potential interventions to improve survival and symptoms while listed for tx for ACHD patients
- Is there systemic AV valve regurgitation that reduces SV -Can be intervened on
- Is there arrhythmia - Ablation is safe but should be done with appropriate planning and experience
- Treating complications – PLE ?midodrine (based on case series)
- Remember that GDMT is not really applicable in ACHD ?what is ‘normal’ in a systemic RV?
CONSIDER additional procedures = additional risk of surgical interventions = extra sternotomies (make HT higher risk) + more sensitization
Specific considerations in Fontan HTx
- Assessing for requirement of liver / kidney transplant
- Assessment of pulmonary pressures is v important
- High sensitization because often multiple operations
- Re-sternotomy x4! – might require femoral bypass (but this is associated with higher mortality as it implies longer bypass time)
- Planning of connections (e.g., in dextrocardia with TGA, L sided SVC) can require specific ACHD surgeons
- High HLA sensitization eg 90% - makes patients high priority in some places and low priority in others
Treatment for AVSD/VSD
Supportive: antibiotic prophylaxis if dental surgery, medical treatment of symptoms of CHF e.g., diuretic
Surgical: closure prevents RVH and arrhythmias. Repair of associated anomalies at the same time. This usually occurs at 2-5y unless severe MR.
AVSD/ASD: closure is via sternotomy approach, fixing of the defect with pericardial tissue autologously or with Dacron/PTEF patches. Needs extracorporeal support.
Percutaneous transcatheter can be done for secundum ASD
Complete AVSD: 3/12, requires tx of pulmonary vascular resistance if present at birth
ECG and CXR findings for ASD/AVSD
CXR: RAH, RVH, prominent PA and increase in vascular markings
ECG can show RAD, IDHB, RBBB, RAH/RVH.
ASD examination in children:
Left to right shunt -> pink and breathless.
Murmurs due to high volume of flow (blood from left enters right = high RV preload) across small right-sided valves at high pressure. Not due to the shunt itself.
Can hear both an ejection systolic murmur (pulmonary valve) and a mid diastolic murmur (tricuspid valve).
Fixed splitting of S2 due to high P pressures II to high Rv preload
AVSD examination in children
Mixed shunt -> blue and breathless.
Atrial + ventricular components, therefore presents with pulmonary HTN and a large VSD.
May be cyanosed at birth due to retrograde flow through PDA
Murmur audible in the first few weeks, but sometimes cavity os big that no murmur heard
Exam findings in pulmonary stenosis
Mild/moderate stenosis: child pink, RV heave, systolic thrill. ESM. S1 with ejection click and s2 widely split. ESM loudest in P area (left sternal border upper). Intensity NOT related to severity.
Severe stenosis or atresia (duct dependent): cyanosis, heart failure with tricuspid insufficiency, giant A waves in JVP, hepatomegaly and pulsatile liver. S4.
Investigations in PS
CXR: normal heart size, RA dilation, PA dilation post stenosis, low pulmonary blood flow.
Echo is diagnostic, Doppler, determine the amount of stenosis.
ECG may be normal
PS Management
Mild: conservative, follow up with echo
Moderate: if symptomatic, treat as severe.
Severe: surgical intervention, minimally invasive baloon pulmonary valvuloplasty. May do open aproach, valvotomy with inflow occlusion, hyopthermia and cardiopulmonary bypass).
TOF definition
Cyanotic cardiac malformation encompassing these four:
* Large VSD
* Infundibular and valvular pulmonary stenosis
* Right ventricualr hypertrophy
* Overriding of aorta relative to ventricular septum (superior to VSD)
`
Aetiology of TOF
Complex abnormalities due to abnormal development of right ventricular infindibulum.
Related to fetal hydantoin, CBZ, fetal alcohol, DiGeorige, trisomy 21.
Haemodynamic consequences of TOF that cause R>L shunting
PS/RVOTO -> high RV pressure -> RVH + increase R-L shunting -> deoxygenated blood in circulation
Hypoxic spells occur in times of high R>L shunting
Examination in TOF children
Birth: cyanotic. Low BW
Infant: hypoxic spells, harsh ESM at left sternal edge (PS), loud single second heart sound, parasternal heave for RVH
Child: often adopt squatting position in spells to increase systemic vascular resistance, decreasing R-L shunt.
Signs of HF, developmental delay.
CXR findings in TOF
CXR may show RVH, boot shaped heart, low lung markings and vascularity. ECG. (RAD, RVH, RBBB
Management of TOF
Treat cyanotic spells: soothe, knee chest position, calm increase venous return. If prolonged, IV morphine for sedation.
Corrective surgical intervention: VSD patch to close, treat other associated anomalies too. Repair at >1y.
Preoperative stabilisation with PGE2 to keep PDA open.
Prognosis in TOF
Hypoxia, MI, ischaemia in brain, secondary polycythaemia (therefore leading to thrombotic events), infective endocarditis, cerebral abscess, delayed growth and puberty.
Pre surgery 30% mortality in first year of life, 75% by 10y. Now, 90% survive to be adults. .
What is tricuspid atresia?
Tricuspid valve never develops, leading to no connection between right atrium (RA) and right ventricle (RV)
It is associated with atrial septal defect (ASD), large ventricular septal defect (VSD), and patent ductus arteriosus (PDA).
What are the associated conditions with tricuspid atresia?
- ASD
- Large VSD
- PDA
These conditions contribute to the altered hemodynamics in tricuspid atresia.
What is the mortality rate of untreated tricuspid atresia in the first year of life?
90%
This highlights the severe nature of the condition when left untreated.
Describe the blood flow in tricuspid atresia.
SVR enters RA, crosses ASD, mixes with PVR in LA, through MV into LV, then to hypoplastic RV and either aorta or pulmonary artery
This pathway illustrates the abnormal circulation due to the absence of a functional tricuspid valve.
What is the primary goal in managing tricuspid atresia?
Balance flow and saturations
Effective management aims to optimize systemic and pulmonary blood flow.
What are the three key issues in tricuspid atresia management?
- Too little systemic outflow
- Pulmonary circulation overload and Eisenmenger’s
- Saturations and mixing of blood
These issues complicate the management of patients with tricuspid atresia.
What is the purpose of pulmonary artery bands (PA bands) in tricuspid atresia?
Increase pulmonary vascular resistance to avoid over-circulation to the lungs
This surgical intervention aims to create a functional pulmonary stenosis.
What are the stages of the Fontan procedure?
- Stage 1: Norwood procedure
- Stage 2: Bidirectional Glenn
- Stage 3: Fontan
Each stage progressively improves the hemodynamics in patients with single ventricle physiology.
What does the Norwood procedure involve?
- Close PDA
- Create or widen ASD
- Create neo-aorta
- Create new venous flow into PA
The Norwood procedure is the first surgical intervention in the Fontan sequence.
What is the classic Fontan operation associated with?
Massive RA dilation and significant atrial tachycardias
This is due to increased pressure and volume load in the right atrium.
What types of atrial septal defect (ASD) exist?
- Secundum ASD (80%)
- Primum ASD (15%)
- Superior sinus venosus defect (5%)
- Inferior sinus venosus defect (<1%)
- Unroofed coronary sinus (<1%)
Each type has distinct anatomical features and clinical implications.
What is a common symptom of ASD in adulthood?
Exertional shortness of breath (SOB)
Symptoms may not present until adulthood, often beyond the fourth decade.
What is the significance of the Qp:Qs ratio?
Indicates the ratio of pulmonary blood flow to systemic blood flow
A ratio greater than 1 suggests left-to-right shunting.
What are the types of ventricular septal defect (VSD)?
- Type 1: Subaortic
- Type 2: Membranous
- Type 3: Inlet
- Type 4: Muscular
- Gerbode: Left ventricular to right atrial communication
Each type has different implications for management and outcomes.
What complications can arise with advancing age in patients with VSD?
- Double chamber RV
- Prolapse of RCC of aortic valve
- Arrhythmias
- Late LV dysfunction
- Endocarditis risk
These complications necessitate ongoing management and surveillance.
What is total anomalous pulmonary venous return (TAPVR)?
Abnormality where pulmonary veins do not connect to the left atrium
Blood connects to the right atrium via an ASD, creating a complex circulation pattern.
What is the characteristic murmur associated with patent ductus arteriosus (PDA)?
Machinery-like murmur
This sound is typically heard in late diastole and early systole.
What is hypoplastic left heart syndrome?
Underdevelopment or complete absence of the left side of the heart
This condition is often managed using a modified Fontan procedure.
What is the primary treatment strategy for patients with Ebstein anomaly?
Optimize heart failure medications and consider surgical repair if severe tricuspid regurgitation
Regular follow-up is crucial for managing this condition.
What are common symptoms associated with coarctation of the aorta (CoA)?
- Headache
- Nosebleeds
- Dizziness
- Shortness of breath
- Cold extremities
These symptoms arise from differential blood flow due to the stenosis.
What are key symptoms of CoA?
Headache, nosebleeds, dizziness, tinnitus, shortness of breath, abdominal angina, claudication, cold feet
These symptoms may indicate underlying cardiovascular issues.
What are the risks associated with CoA?
Risks include:
* Intracranial haemorrhage
* Infective endocarditis (IE)
* Aortic rupture/dissection
* Premature coronary and cerebral artery disease
* Associated heart defects
These complications can arise from untreated or severe left heart failure.
What examination findings may suggest CoA?
Systolic murmur, radio-femoral delay, cold extremities
These findings can help in diagnosing left heart failure.
What is the preferred management for CoA?
Blood pressure control, interventional stenting preferred to surgery
Stenting is indicated for >50% narrowing, peak gradient >20mmHg, or arterial hypertension.
What complications can occur post-repair of CoA?
Re-coarctation, aneurysms, dissections
These complications can significantly impact patient outcomes.
What characterizes Transposition of the Great Arteries (TGA)?
AV concordance and ventriculo-arterial discordance: aorta originates from RV, PA from LV
This condition leads to significant circulatory issues if not corrected.
What is the difference between simple and complex TGA?
Simple TGA has no associated congenital anomalies, while complex TGA includes anomalies such as VSD, LVOTO, and CoA
Simple TGA is dependent on PDA for survival.
What are common associated anomalies with complex TGA?
- Ventricular Septal Defect (VSD) ∼45%
- Left Ventricular Outflow Tract Obstruction (LVOTO) ∼25%
- Coarctation of Aorta (CoA) ∼5%
These anomalies complicate the management of TGA.
What surgical technique is used for simple TGA?
Arterial switch procedure
This is the standard surgical approach for correcting simple TGA.
What are the long-term risks after arterial switch for TGA?
High risk of:
* RV failure
* Secondary progressive TR
* Bradycardia
* SVT/arrhythmias
* Baffle stenosis
* Baffle leakage
* Venous/arterial obstruction
* LVOTO
* PAH
These complications require ongoing management and monitoring.
What is the natural history of TGA without surgical repair?
Extremely poor, with survival to adult life being the exception
This is only possible if there is a large persistent PFO/ASD/VSD.
What percentage of dTGA and Fontain patients experience symptomatic heart failure?
22% of dTGA and 40% of Fontain patients
This highlights the prevalence of heart failure in patients with congenital heart disease.
What challenges do ACHD patients face regarding heart transplants?
Less likely to receive a transplant, barriers include:
* Policies
* Sensitization
* Mental health
* Size matching in young people
* Anatomical consideration
These factors contribute to disparities in transplant access.
What are some anesthetic considerations for ACHD patients?
Poor tolerance to anesthetics and fluid shifts
Special care is needed during anesthesia in these patients.
What is Fontain palliation?
A series of operations for ACHD patients who cannot undergo biventricular repair
It reroutes venous blood directly to the lungs to bypass the heart.
What is the significance of regionalization in the context of ACHD outcomes?
It can help improve outcomes for ACHD patients
High-volume centers tend to have better outcomes.
What is the management approach for advanced heart failure in ACHD patients?
Assess for systemic AV valve regurgitation, arrhythmias, and consider additional surgical interventions
This may involve complex decision-making and planning.
What are the potential complications post-operative management for ACHD?
Restoration of ‘normal’ circulation can lead to:
* Significant organ dysfunction
* Kidney injury
* Abnormal LFTs
* Slow ventilation weans
These complications require careful monitoring and management.
