CVS Flashcards
1
Q
What defines a ventricular septal defect (VSD)?
A
VSD is a congenital defect characterized by an abnormal communication between the left and right ventricles through the interventricular septum.
2
Q
What are the anatomical types of VSD and their frequencies?
A
Types:
- Perimembranous (~80%)
- Muscular (5–20%)
- Inlet (AV canal type)
- Outlet (subarterial, infundibular)
- Malalignment type
3
Q
What is the embryological origin of VSDs?
A
VSDs result from failure of fusion of components of the interventricular septum during embryogenesis, particularly the endocardial cushions and conotruncal ridges.
4
Q
How does the size of a VSD influence shunt physiology?
A
Small defects: High resistance, small shunt volume, less hemodynamic burden.
Large defects: Low resistance, high-volume left-to-right shunt, risk of CHF and pulmonary hypertension.
5
Q
What is a restrictive vs. non-restrictive VSD?
A
Restrictive VSD: high velocity flow, pressure gradient between ventricles maintained.
Non-restrictive VSD: equalized pressures, large volume shunt, severe symptoms.
6
Q
How does VSD present in neonates vs. older infants?
A
Neonates with large VSD may be asymptomatic initially (due to high PVR), but develop CHF around 6–8 weeks as PVR drops.
Older infants show signs of failure to thrive, tachypnea, feeding difficulty.
7
Q
What is the clinical course of small muscular VSDs?
A
Small muscular VSDs often close spontaneously within the first 2 years of life without intervention.
8
Q
What is the classic murmur of VSD and when does it appear?
A
A harsh pansystolic (holosystolic) murmur best heard at the lower left sternal border. It typically appears after the first few days of life as PVR declines.
9
Q
What signs indicate a large VSD in physical examination?
A
Signs include tachypnea, hepatomegaly, diaphoresis, failure to thrive, active precordium, bounding pulses if PDA is associated.
10
Q
What complications are associated with large VSDs?
A
Complications:
- Congestive heart failure
- Pulmonary overcirculation and edema
- Growth failure
- Pulmonary hypertension
- Eisenmenger syndrome
- Infective endocarditis
11
Q
What role does pulmonary vascular resistance play in VSD physiology?
A
High PVR in neonates limits shunting initially; as it drops, the left-to-right shunt increases. Chronically elevated PVR due to large shunts can lead to pulmonary vascular obstructive disease.
12
Q
What is Eisenmenger syndrome in the context of VSD?
A
In untreated large VSDs, increased pulmonary pressure leads to reversal of shunt (right-to-left), causing cyanosis, clubbing, and polycythemia—termed Eisenmenger syndrome.
13
Q
Which imaging modalities help in diagnosing VSD?
A
CXR: cardiomegaly, increased pulmonary vascularity
ECG: LA/LV hypertrophy or biventricular hypertrophy
Echo: confirms site, size, and flow
Cath: assesses PVR when pulmonary hypertension is suspected
14
Q
What findings on echocardiogram confirm hemodynamic significance of VSD?
A
Echo findings:
- Size and site of defect
- Shunt direction (color Doppler)
- Left heart enlargement
- LA/Ao ratio >1.5
- Pulmonary artery pressure estimation
15
Q
What is the role of cardiac catheterization in VSD evaluation?
A
Cath is used when echo is inconclusive, or when estimating pulmonary vascular resistance in borderline operability cases before surgical correction.
16
Q
What syndromes are commonly associated with VSD?
A
Syndromes:
- Down syndrome (especially AV canal type)
- DiGeorge syndrome (22q11 deletion)
- Trisomy 13, 18
- Holt-Oram syndrome
- VACTERL association
17
Q
What is the natural history of VSDs by defect size?
A
Small: likely to close, usually asymptomatic
Moderate: may need monitoring or closure
Large: persistent, symptomatic, high risk for complications
18
Q
When is spontaneous closure of VSD most likely?
A
Spontaneous closure is most likely in:
- Small size (<3 mm)
- Muscular or perimembranous type
- Detected in early infancy
- Absence of chamber enlargement
19
Q
What are medical management strategies for symptomatic VSDs?
A
Management:
- Diuretics (e.g., furosemide)
- ACE inhibitors (e.g., captopril)
- High-calorie feeds or NG feeding
- Monitoring growth and heart size
- Treat intercurrent infections
20
Q
What are indications for surgical or device closure of VSD?
A
Closure indicated if:
- Large defect with CHF not controlled medically
- Pulmonary hypertension
- Failure to thrive
- Aortic valve prolapse or regurgitation
- Risk of Eisenmenger
21
Q
What defines an atrial septal defect (ASD)?
A
ASD is a congenital heart defect characterized by a communication between the left and right atria, allowing left-to-right shunting of blood.
22
Q
What are the different types of ASDs and their characteristics?
A
Types of ASD:
- Ostium secundum (center of atrial septum, ~75%)
- Ostium primum (inferior septum, part of AV canal)
- Sinus venosus (near SVC or IVC entry)
- Coronary sinus (rare)
23
Q
What is the embryological basis of ASD development?
A
ASDs result from incomplete fusion of septum primum and septum secundum, or from defects in absorption of sinus venosus or endocardial cushion development.
24
Q
What are the hemodynamic effects of ASD?
A
ASDs allow left-to-right shunting, increasing RV volume and pulmonary blood flow, leading to right heart dilation and possible arrhythmias over time.
25
What is the clinical presentation of ASD in children?
Many children are asymptomatic. In larger defects, symptoms may include fatigue, frequent respiratory infections, and decreased exercise tolerance.
26
How does ASD murmur differ from other murmurs?
ASD murmurs are not due to the defect itself but to increased flow across the pulmonary valve. It presents as a systolic ejection murmur at the pulmonary area.
27
What are the auscultatory features of ASD?
Typical auscultatory findings:
- Wide, fixed splitting of S2 (hallmark)
- Systolic ejection murmur at upper left sternal border
- Possible mid-diastolic murmur at LLSB (increased tricuspid flow)
28
What ECG findings are characteristic of secundum ASD?
Secundum ASD ECG:
- Right axis deviation
- Incomplete right bundle branch block (RBBB)
- Sometimes atrial enlargement
29
What ECG features help identify primum ASD?
Primum ASD ECG:
- Left axis deviation
- First-degree AV block
- May show superior QRS axis
30
What chest X-ray findings suggest a significant ASD?
CXR:
- Cardiomegaly
- Enlarged right atrium and ventricle
- Prominent pulmonary artery and increased vascular markings
31
What is the natural course of secundum ASDs?
Many secundum ASDs <6 mm close spontaneously by age 2–3 years, especially if diagnosed in infancy.
32
Which types of ASD are unlikely to close spontaneously?
Primum, sinus venosus, and large secundum ASDs (>8 mm) rarely close spontaneously and typically require closure.
33
What complications can arise from untreated ASD?
Untreated ASDs may lead to:
- Right heart failure
- Atrial arrhythmias
- Pulmonary hypertension
- Paradoxical embolism
- Stroke or brain abscess
34
What is the role of echocardiography in ASD diagnosis?
Echocardiography confirms diagnosis, identifies type, estimates shunt size, and assesses right heart dimensions and pulmonary pressure. Bubble contrast echo may detect PFO.
35
What is the importance of the Qp:Qs ratio in ASD?
Qp:Qs >1.5:1 indicates a significant shunt requiring closure. It helps quantify shunt magnitude and guide management decisions.
36
What is paradoxical embolism and how is it related to ASD?
Paradoxical embolism occurs when a thrombus bypasses the lungs via a right-to-left shunt (e.g., ASD/PFO), causing stroke or systemic embolism.
37
Which genetic syndromes are associated with ASD?
ASDs are seen in:
- Holt-Oram syndrome
- Down syndrome (with AV canal defects)
- Ellis-van Creveld syndrome
- Noonan syndrome (less common)
38
What is the indication for ASD closure?
Closure indicated if:
- Right heart dilation
- Qp:Qs >1.5
- Symptoms or decreased exercise tolerance
- Paradoxical embolism or stroke history
39
How is percutaneous device closure of ASD performed?
Device closure is performed via cardiac catheterization. A septal occluder is deployed across the defect. Requires adequate rims and suitable anatomy.
40
What are surgical indications for ASD when device closure is not possible?
Surgical closure is needed if:
- Inadequate septal rims
- Large primum or sinus venosus defects
- Associated anomalous pulmonary venous return
41
What is Patent Ductus Arteriosus (PDA) and its physiological basis?
PDA is a persistent postnatal communication between the descending aorta and pulmonary artery. It leads to left-to-right shunting, increasing pulmonary blood flow and left heart volume load.
42
What is the normal role of the ductus arteriosus during fetal circulation?
In fetal life, the ductus arteriosus diverts blood away from the non-functioning lungs by connecting the pulmonary artery to the aorta.
43
What triggers ductus arteriosus closure after birth?
Closure is triggered by increased oxygen tension and decreased circulating prostaglandins (especially PGE2) after birth.
44
What is the difference between functional and anatomical closure of the ductus arteriosus?
Functional closure (vasoconstriction) occurs within 12-48 hours. Anatomical closure (fibrosis and remodeling) completes over 1–2 weeks.
45
What are the risk factors for PDA persistence in neonates?
Risk factors include prematurity, perinatal hypoxia, respiratory distress, maternal rubella, and high altitude birth.
46
How does PDA present clinically in a premature infant?
In preterms, PDA may present with apnea, tachypnea, bounding pulses, widened pulse pressure, and feeding difficulties.
47
What are the features of a hemodynamically significant PDA?
Features include hyperdynamic precordium, tachycardia, continuous murmur, wide pulse pressure, and signs of CHF or poor systemic perfusion.
48
Describe the murmur classically heard in PDA.
A continuous 'machinery' murmur best heard at the left infraclavicular area, often radiating to the back, and peaking around day 2–5 of life.
49
How does PDA affect systemic perfusion and oxygenation?
Left-to-right shunting reduces diastolic pressure and systemic perfusion, particularly affecting organs like the kidney, gut, and brain.
50
What are the ECG findings in moderate-to-large PDA?
ECG shows left atrial and left ventricular hypertrophy; large shunts may cause biventricular enlargement due to volume overload.
51
What CXR findings are typical in large PDA?
CXR findings: cardiomegaly, increased pulmonary vascular markings, LA/LV enlargement, and possibly pleural effusions in CHF.
52
What are the echocardiographic signs of significant PDA?
Echocardiography shows ductal flow on color Doppler, LA:Ao ratio >1.5, enlarged LV, retrograde diastolic flow in descending aorta or mesenteric arteries.
53
How is PDA managed medically in preterm infants?
NSAIDs like indomethacin or ibuprofen are first-line for closing PDA in preterm infants by inhibiting prostaglandin synthesis.
54
What are the NSAIDs used for PDA closure and their mechanism?
NSAIDs inhibit COX enzymes, reducing PGE2 levels, leading to ductal constriction and functional closure.
55
When is medical therapy for PDA contraindicated?
Contraindications: renal dysfunction, thrombocytopenia, NEC, GI bleeding, IVH grade III/IV, or duct-dependent congenital heart defects.
56
What are the surgical options for PDA closure?
Surgical ligation is done via left thoracotomy and is considered in preterm infants with failed medical therapy or contraindications.
57
When is percutaneous device closure preferred in PDA?
Device closure is preferred in term infants and children with suitable anatomy and moderate to large PDA, typically after 6 months of age.
58
What complications can arise from untreated large PDA?
Complications: pulmonary hypertension, heart failure, Eisenmenger syndrome, endocarditis, growth failure, and arrhythmias.
59
What conditions can be worsened by an untreated PDA in preterm neonates?
Conditions worsened by PDA: necrotizing enterocolitis, intraventricular hemorrhage, bronchopulmonary dysplasia, and renal hypoperfusion.
60
What are the associated genetic syndromes and conditions with PDA?
PDA is associated with congenital rubella syndrome, CHARGE syndrome, trisomy 13 and 18, and Char syndrome (TFAP2B mutation).
61
What is Tetralogy of Fallot (TOF), and why is it classified as a cyanotic heart disease?
Tetralogy of Fallot is a congenital heart defect with four structural abnormalities that together cause right-to-left shunting and cyanosis, making it the most common cyanotic heart disease beyond infancy.
62
Describe the four classical anatomical components of TOF and their functional impact.
The four components are:
1. Large VSD – allows bidirectional flow
2. RVOT obstruction (infundibular/pulmonary stenosis) – causes RV pressure elevation
3. Overriding aorta – receives blood from both ventricles
4. Right ventricular hypertrophy – secondary to RVOT obstruction.
63
Explain the embryological defect responsible for TOF.
TOF is due to anterior and cephalad malalignment of the infundibular septum, affecting conotruncal separation and leading to narrowed RVOT and misaligned VSD.
64
How does the degree of RVOT obstruction influence the clinical presentation of TOF?
Mild RVOT obstruction results in a left-to-right shunt (less cyanosis). Severe obstruction increases RV pressure, leading to right-to-left shunt through the VSD and significant cyanosis.
65
Why do patients with TOF develop cyanosis, and what determines its severity?
Cyanosis occurs due to deoxygenated blood bypassing the lungs via right-to-left shunt through the VSD, especially when RV pressure exceeds LV pressure.
66
What are 'tet spells' and their pathophysiology?
Tet spells are sudden hypoxic episodes due to acute increase in RVOT obstruction and systemic venous return, increasing right-to-left shunting and decreasing pulmonary blood flow.
67
Describe typical triggers for hypercyanotic (tet) spells in infants with TOF.
Tet spells are typically triggered by crying, feeding, defecation, or fever – all of which increase oxygen demand or decrease systemic vascular resistance, worsening shunt.
68
What are the physical examination findings in a child with uncorrected TOF?
Findings include central cyanosis, clubbing (chronic), loud harsh systolic murmur at left upper sternal border, single S2, and squatting in older children (increases SVR).
69
What are the characteristic features of the murmur heard in TOF?
A harsh systolic ejection murmur at the pulmonary area reflects RVOT obstruction. Intensity correlates inversely with severity—softer murmur in worse obstruction.
70
What radiological signs on chest X-ray suggest TOF?
Boot-shaped heart ('coeur en sabot'), due to RV hypertrophy and uplifted apex; decreased pulmonary vascular markings due to reduced pulmonary flow.
71
How does the ECG pattern in TOF reflect right-sided heart strain?
ECG shows right axis deviation, prominent R waves in V1, and right ventricular hypertrophy. Right atrial enlargement may be seen.
72
What key features are seen on echocardiography in a patient with TOF?
Echo identifies all 4 TOF defects, estimates RVOT gradient, visualizes pulmonary valve and arteries, and confirms aortic override and VSD morphology.
73
When and why is cardiac catheterization required in the evaluation of TOF?
Cath is done for complex anatomy, unclear PA arborization, or pre-intervention planning when noninvasive imaging is insufficient.
74
What are the immediate steps to manage a tet spell in a clinical setting?
Management includes knee-chest position (increases SVR), oxygen (pulmonary vasodilation), morphine (sedation), beta-blockers (relieve infundibular spasm), and bicarbonate if acidotic.
75
What are the long-term preoperative medical strategies in TOF management?
Propranolol may reduce infundibular spasm. Adequate hydration and hematocrit optimization improve oxygen delivery until corrective surgery is done.
76
At what age is elective surgical repair of TOF recommended, and why?
TOF repair is usually performed between 3 to 6 months of age to prevent complications such as polycythemia, tet spells, and right ventricular dysfunction.
77
What are the components of total surgical repair of TOF?
Complete repair includes closure of VSD with a patch and relief of RVOT obstruction (resection of infundibular muscle ± transannular patch or valvotomy).
78
When is a palliative Blalock-Taussig shunt used in TOF, and what does it achieve?
Used in neonates or infants with severe cyanosis who are not surgical candidates yet. The shunt connects the subclavian artery to the pulmonary artery to increase pulmonary blood flow.
79
What postoperative complications are commonly encountered after TOF repair?
Common complications include arrhythmias (esp. RBBB, ventricular arrhythmias), pulmonary regurgitation, RV dilation, residual VSD, and need for reoperation.
80
List the genetic syndromes and extracardiac anomalies commonly associated with TOF.
Associated syndromes:
- DiGeorge syndrome (22q11 deletion)
- Down syndrome (if AV canal present)
- CHARGE syndrome
- Hemifacial microsomia
- VACTERL association
81
What is Transposition of the Great Arteries (TGA)?
TGA is a congenital heart defect where the aorta arises from the right ventricle and the pulmonary artery from the left ventricle, resulting in parallel, non-communicating circulations.
82
What is the difference between d-TGA and l-TGA?
d-TGA (dextro-TGA): atrioventricular concordance with ventriculoarterial discordance; causes cyanosis.
l-TGA (levo-TGA): both atrioventricular and ventriculoarterial discordance; physiologically corrected but leads to RV as systemic ventricle.
83
What is the embryological cause of d-TGA?
d-TGA results from failure of the truncoconal (spiral) septum to rotate during embryogenesis, leading to transposition of the great arteries.
84
What is the physiological consequence of d-TGA at birth?
At birth, systemic and pulmonary circulations function in parallel rather than in series, so oxygenated blood does not reach systemic tissues unless mixing occurs.
85
Why is mixing of oxygenated and deoxygenated blood essential in d-TGA?
Without mixing (PFO, ASD, VSD, or PDA), d-TGA is incompatible with life due to severe systemic hypoxia.
86
What clinical features are typical of d-TGA in the newborn?
Newborns present with profound cyanosis within the first few hours of life, often unresponsive to oxygen therapy ('cyanosis gap').
87
What is the importance of a PDA or PFO in TGA?
A PDA or PFO allows critical mixing of blood between systemic and pulmonary circulations, temporarily improving oxygenation.
88
How does cyanosis in d-TGA differ from that in TOF?
Cyanosis in d-TGA is present from birth and often severe, in contrast to TOF where cyanosis may be delayed or intermittent.
89
What are the findings on physical examination in an infant with d-TGA?
Cyanosis, tachypnea without distress, loud single S2 (due to anteriorly placed aorta), and soft systolic murmur if VSD or PS is present.
90
What are the typical chest X-ray findings in d-TGA?
CXR shows 'egg-on-a-string' heart (narrow mediastinum), due to anteroposterior alignment of great vessels, and increased pulmonary vascular markings.
91
What are the ECG features of d-TGA in the neonatal period?
Neonatal ECG is usually normal or shows right ventricular dominance as in normal newborns. LV forces diminish if mixing is inadequate.
92
What key features are seen on echocardiography in d-TGA?
Echo shows origin of the aorta from the RV and pulmonary artery from LV; evaluates associated defects (ASD, VSD, PDA).
93
What is the role of balloon atrial septostomy in d-TGA management?
Balloon atrial septostomy (Rashkind procedure) enlarges the foramen ovale to enhance atrial-level mixing and systemic oxygenation.
94
What is the function of prostaglandin E1 (PGE1) in TGA?
PGE1 maintains ductal patency, improving mixing and systemic oxygenation until definitive surgery is performed.
95
What is the definitive surgical treatment for d-TGA?
The arterial switch operation (ASO) is the gold-standard corrective surgery for d-TGA, usually done within the first 1–2 weeks of life.
96
What are the steps of the arterial switch operation (ASO)?
ASO involves transection of great arteries, reanastomosis to correct ventriculoarterial discordance, and reimplantation of coronary arteries into the neoaorta.
97
What complications are associated with delayed diagnosis of d-TGA?
Delayed diagnosis results in severe hypoxia, acidosis, neurologic damage, and death without surgical intervention.
98
How is l-TGA different from d-TGA in terms of pathophysiology?
In l-TGA, the systemic venous return still reaches the lungs and pulmonary venous return goes to the body, but the RV functions as the systemic ventricle, leading to late complications.
99
What long-term complications are associated with l-TGA?
l-TGA can lead to systemic RV failure, tricuspid regurgitation, and heart block due to abnormal conduction system over time.
100
Which genetic syndromes or anomalies are commonly associated with TGA?
TGA is associated with 22q11 deletion (DiGeorge syndrome), maternal diabetes, and extracardiac anomalies such as situs inversus or asplenia.
101
What is Tricuspid Atresia?
Tricuspid atresia is a congenital heart defect characterized by complete absence of the tricuspid valve, resulting in no direct communication between the right atrium and right ventricle.
102
What is the embryological basis of tricuspid atresia?
It results from failure of development of the tricuspid valve and associated right ventricular hypoplasia due to reduced blood flow into the right ventricle during embryogenesis.
103
What are the types of tricuspid atresia based on associated great artery anatomy?
Types:
- Type I: normally related great arteries
- Type II: d-transposition of great arteries
- Type III: malposition of great arteries
- Further classified based on pulmonary blood flow (decreased, increased, or normal).
104
Why is tricuspid atresia classified as a cyanotic heart defect?
Due to lack of right-to-pulmonary blood flow, deoxygenated blood must reach the lungs via shunts, making the condition cyanotic without mixing lesions.
105
What intracardiac shunts are necessary for survival in tricuspid atresia?
Survival requires right-to-left and left-to-right shunting via an atrial septal defect (ASD), ventricular septal defect (VSD), and/or patent ductus arteriosus (PDA).
106
What clinical features are typical in neonates with tricuspid atresia?
Neonates present with central cyanosis, poor feeding, tachypnea, and signs of hypoxia. Murmurs depend on associated VSD and pulmonary blood flow.
107
How does the presence of pulmonary stenosis affect the presentation?
Pulmonary stenosis or atresia exacerbates cyanosis due to limited pulmonary flow. Without obstruction, pulmonary overcirculation can lead to heart failure.
108
What is the importance of a patent ductus arteriosus (PDA) in tricuspid atresia?
A PDA provides pulmonary blood flow in duct-dependent physiology. Closure of the ductus can be life-threatening in such cases.
109
What are the physical examination findings in tricuspid atresia?
Findings include cyanosis, single S2 (absent pulmonary component), systolic murmur from VSD or increased flow, and hepatomegaly in CHF.
110
What ECG findings are characteristic of tricuspid atresia?
ECG shows left axis deviation (due to hypoplastic RV), left ventricular hypertrophy (dominant systemic ventricle), and superior QRS axis.
111
What chest X-ray findings may be seen in tricuspid atresia?
CXR may show decreased or increased pulmonary vascularity depending on pulmonary blood flow. Cardiomegaly may be present with increased flow.
112
What are the echocardiographic features of tricuspid atresia?
Echo reveals absence of tricuspid valve, hypoplastic RV, ASD, VSD, and assesses pulmonary outflow tract and great artery alignment.
113
What is the role of cardiac catheterization in tricuspid atresia?
Cath is done when echo is inconclusive, to assess pulmonary vascular resistance, or before surgical staging. It defines anatomy and pressures.
114
How does the physiology of tricuspid atresia change over time?
Initially duct-dependent, physiology evolves to either pulmonary overcirculation (leading to CHF) or undercirculation (cyanosis) based on VSD and pulmonary stenosis.
115
What are the initial medical management strategies in neonates?
Initial management includes PGE1 infusion to keep PDA open, oxygen as needed, diuretics for CHF, and preparation for surgical palliation.
116
What is the role of prostaglandin E1 in tricuspid atresia?
PGE1 maintains ductal patency to ensure pulmonary blood flow when the pulmonary valve or RVOT is hypoplastic or atretic.
117
What surgical interventions are used in staged palliation of tricuspid atresia?
Staged surgery includes:
1. Blalock-Taussig shunt (neonatal)
2. Bidirectional Glenn (4–6 months)
3. Fontan completion (2–4 years).
118
What is the Glenn procedure and its role in management?
Glenn procedure connects the superior vena cava to the pulmonary artery, allowing passive flow of venous blood to lungs without RV involvement.
119
What is the Fontan procedure and its physiological rationale?
Fontan procedure connects the inferior vena cava to pulmonary artery, completing systemic venous return to lungs without a pumping chamber.
120
What long-term complications are associated with Fontan circulation?
Fontan complications include protein-losing enteropathy, arrhythmias, thromboembolism, hepatic congestion and fibrosis, and heart failure over time.
121
What is Total Anomalous Pulmonary Venous Return (TAPVR)?
TAPVR is a congenital heart defect in which all pulmonary veins drain into the systemic venous circulation instead of the left atrium.
122
How is TAPVR classified anatomically?
TAPVR is classified into:
1. Supracardiac (50%) – veins drain into SVC or innominate vein
2. Cardiac (20%) – drain into coronary sinus or right atrium
3. Infracardiac (20%) – drain into IVC or portal vein
4. Mixed (10%) – combination of pathways.
123
What is the embryological error leading to TAPVR?
TAPVR results from failure of the pulmonary venous plexus to connect with the left atrium during embryogenesis, instead connecting to systemic veins.
124
Why is an atrial-level communication essential in TAPVR?
An atrial septal defect or patent foramen ovale is required for oxygenated blood to reach the left atrium and systemic circulation.
125
What is the pathophysiological impact of TAPVR on circulation?
Pulmonary venous return is diverted to the right heart, causing volume overload in right atrium and ventricle, and leading to pulmonary overcirculation.
126
What are the clinical features of obstructed vs. unobstructed TAPVR?
Obstructed TAPVR: severe cyanosis, respiratory distress, shock-like state.
Unobstructed TAPVR: mild cyanosis, tachypnea, signs of heart failure over days to weeks.
127
What are the key differences between supracardiac and infracardiac TAPVR?
Supracardiac TAPVR: commonly unobstructed, snowman sign on CXR.
Infracardiac TAPVR: often obstructed due to venous compression by diaphragm or hepatic circulation.
128
What is the typical age of presentation of TAPVR?
Presentation usually occurs in the neonatal period, especially in obstructed types; unobstructed types may present later in infancy with CHF.
129
What physical examination findings are common in obstructed TAPVR?
In obstructed TAPVR: marked cyanosis, respiratory distress, hepatomegaly, and poor perfusion are prominent findings.
130
What are the auscultatory findings in TAPVR?
A loud, single S2 is common due to pulmonary hypertension. A systolic murmur may be present from increased flow across tricuspid valve.
131
What chest X-ray findings suggest supracardiac TAPVR?
Supracardiac TAPVR: 'snowman sign' or 'figure-of-8' appearance due to dilated vertical vein and SVC/innominate vein confluence.
132
How does ECG appear in a neonate with TAPVR?
ECG typically shows right axis deviation and right ventricular hypertrophy due to right-sided volume and pressure overload.
133
What role does echocardiography play in diagnosing TAPVR?
Echo identifies anomalous drainage, assesses atrial-level shunt, and checks for obstruction or chamber enlargement. It is the primary diagnostic tool.
134
When is cardiac CT or MRI indicated in TAPVR evaluation?
Cardiac CT or MRI is used for detailed anatomical mapping when echo findings are inconclusive or before surgical planning in complex cases.
135
What is the definitive treatment for TAPVR?
Surgery is required urgently in obstructed TAPVR and electively in unobstructed forms. There is no role for medical therapy alone.
136
What is the surgical approach to TAPVR repair?
Surgical repair involves rerouting the pulmonary veins to the left atrium and closing the ASD or PFO to eliminate right-to-left shunting.
137
What are complications of TAPVR repair?
Complications include pulmonary venous obstruction, arrhythmias, low cardiac output syndrome, and residual or recurrent shunting.
138
What are the postoperative follow-up concerns in TAPVR patients?
Follow-up is needed for surveillance of pulmonary vein stenosis, right ventricular function, and exercise tolerance over time.
139
What congenital syndromes or defects are associated with TAPVR?
TAPVR may be associated with heterotaxy syndrome, asplenia/polysplenia, and other complex congenital heart defects such as AV canal defects.
140
What is the prognosis after surgical correction of TAPVR?
Prognosis depends on timing of diagnosis and repair. Early surgical repair of unobstructed TAPVR has >90% survival. Obstructed TAPVR has higher perioperative risk.
141
What is Truncus Arteriosus?
Truncus arteriosus is a rare congenital heart defect where a single arterial trunk arises from the heart and gives rise to the systemic, pulmonary, and coronary circulations.
142
What is the embryological basis of truncus arteriosus?
It results from failure of the truncoconal septum to form and divide the outflow tract into the aorta and pulmonary artery during embryonic development.
143
What are the types of truncus arteriosus based on the Collett and Edwards classification?
Collett and Edwards classification:
Type I – main pulmonary artery arises from common trunk before bifurcation
Type II – separate pulmonary arteries arise from the posterior aspect of truncus
Type III – pulmonary arteries arise laterally and separately
Type IV – (no longer used) considered a form of pulmonary atresia.
144
How does truncus arteriosus affect systemic and pulmonary circulation?
Systemic and pulmonary circulations receive blood from the same trunk, resulting in complete mixing and volume overload to the lungs, causing early CHF.
145
What is the role of the truncal valve in the pathophysiology of this defect?
The truncal valve sits over the large VSD and may be dysplastic or regurgitant, contributing to volume overload and worsening heart failure.
146
What are common clinical features in neonates with truncus arteriosus?
Neonates typically present with cyanosis, tachypnea, feeding difficulties, failure to thrive, and signs of congestive heart failure within the first 2–3 weeks of life.
147
When does truncus arteriosus typically present clinically?
Presentation is usually within the first week to month of life as pulmonary vascular resistance falls and pulmonary overcirculation worsens.
148
What are the physical examination findings in truncus arteriosus?
Findings include bounding pulses, wide pulse pressure, active precordium, cyanosis, and signs of heart failure such as hepatomegaly and respiratory distress.
149
What are the auscultatory findings in truncus arteriosus?
A systolic ejection murmur from truncal valve flow or VSD, and an early diastolic murmur if truncal valve regurgitation is present. Loud single S2.
150
What are the characteristic chest X-ray findings in truncus arteriosus?
CXR typically shows cardiomegaly, increased pulmonary vascular markings, and a right aortic arch in about 30% of cases.
151
What are the ECG findings associated with truncus arteriosus?
ECG shows biventricular hypertrophy due to volume overload of both ventricles, sometimes with left axis deviation.
152
What key features are seen on echocardiography in truncus arteriosus?
Echo reveals a single arterial trunk overriding a large VSD, origin of pulmonary arteries, truncal valve morphology, and assessment of regurgitation.
153
What is the significance of a truncal valve abnormality?
The truncal valve may be bicuspid, tricuspid, or quadricuspid, and often regurgitant. Significant regurgitation increases surgical complexity and risk.
154
What other congenital anomalies are commonly associated with truncus arteriosus?
Associated anomalies include interrupted aortic arch, right aortic arch, DiGeorge syndrome (22q11 deletion), and coronary anomalies.
155
What is the definitive management of truncus arteriosus?
Surgical correction is required early in infancy and involves VSD closure, separation of pulmonary arteries, and right ventricle to pulmonary artery conduit placement.
156
What are the components of surgical repair for truncus arteriosus?
Repair includes closure of the VSD so the left ventricle ejects into the truncal root, removal of pulmonary arteries from truncus, and RV-PA conduit placement.
157
What postoperative complications are associated with truncus repair?
Post-op complications include conduit stenosis, truncal valve dysfunction, arrhythmias, and residual VSD or pulmonary artery stenosis.
158
Why is early surgical intervention important in truncus arteriosus?
Without surgical repair, most infants die within the first year due to heart failure and pulmonary vascular disease. Early repair improves survival and outcomes.
159
What is the long-term prognosis after surgical correction of truncus arteriosus?
Survival exceeds 85% at 10 years post-repair in experienced centers, though reoperations for conduit replacement are common in adolescence.
160
Which genetic syndromes are frequently associated with truncus arteriosus?
Truncus arteriosus is strongly associated with 22q11.2 deletion syndrome (DiGeorge), and may also be part of VACTERL or CHARGE associations.
161
What is Pulmonary Atresia?
Pulmonary atresia is a congenital heart defect where there is complete obstruction of blood flow from the right ventricle to the pulmonary artery, preventing direct flow to the lungs.
162
How is pulmonary atresia classified anatomically?
It is classified into:
- Pulmonary atresia with intact ventricular septum (PA/IVS)
- Pulmonary atresia with ventricular septal defect (PA/VSD)
163
What is the embryological defect leading to pulmonary atresia?
Pulmonary atresia results from abnormal development or complete absence of the pulmonary valve, often with underdevelopment of the right ventricular outflow tract.
164
What distinguishes pulmonary atresia with intact ventricular septum (PA/IVS) from pulmonary atresia with VSD?
PA/IVS has no VSD; the right ventricle is often hypoplastic.
PA/VSD has a large VSD and anatomy resembles severe TOF, often with major aortopulmonary collateral arteries (MAPCAs).
165
What is the pathophysiology of PA/IVS?
In PA/IVS, blood cannot exit the RV into the pulmonary arteries, requiring flow through a PDA to reach the lungs. RV may be severely hypoplastic.
166
Why is a patent ductus arteriosus (PDA) critical in pulmonary atresia?
In both forms, pulmonary blood flow depends on a PDA. Closure of the ductus results in rapid hypoxemia, acidosis, and death.
167
What clinical features are typical of a neonate with pulmonary atresia?
Neonates present with profound cyanosis, tachypnea, lethargy, and often shock if ductus closure occurs without intervention.
168
What physical examination findings are seen in pulmonary atresia?
Findings include severe cyanosis, weak peripheral pulses if ductus is closing, hepatomegaly, and signs of poor perfusion or acidosis.
169
What auscultatory findings are typical in pulmonary atresia?
Murmurs are variable; a continuous murmur may be heard from PDA flow. Often there is no pulmonary valve murmur since the valve is absent or closed.
170
What are the chest X-ray findings in pulmonary atresia?
CXR findings:
- PA/IVS: normal or mildly enlarged heart size, decreased pulmonary vascular markings
- PA/VSD: cardiomegaly, increased pulmonary markings if MAPCAs are large.
171
What are the characteristic ECG findings in pulmonary atresia?
ECG:
- PA/IVS: left axis deviation, right atrial enlargement, and diminished RV forces due to hypoplastic RV
- PA/VSD: RV hypertrophy and right axis deviation.
172
What is the role of echocardiography in diagnosing pulmonary atresia?
Echo defines anatomy: presence/absence of VSD, RV size and function, pulmonary artery anatomy, presence of coronary fistulas (PA/IVS specific).
173
What other imaging modalities assist in pulmonary atresia assessment?
Cardiac catheterization and CT angiography are often used to delineate pulmonary blood supply, particularly MAPCAs in PA/VSD.
174
What is the role of PGE1 infusion in pulmonary atresia management?
PGE1 infusion maintains PDA patency, ensuring pulmonary blood flow until definitive or palliative intervention can be planned.
175
What are the initial emergency management steps for a neonate with pulmonary atresia?
Initial management includes oxygen, PGE1 to maintain ductus, correcting acidosis, and urgent cardiology and surgical consultation.
176
What surgical options are available for PA/IVS?
PA/IVS surgical options include PDA-dependent shunt (Blalock-Taussig shunt), RV outflow reconstruction, or single ventricle palliation (Fontan) if RV is severely hypoplastic.
177
How is pulmonary atresia with VSD (PA/VSD) managed differently?
PA/VSD management often involves unifocalization (surgical connection of MAPCAs), VSD closure, and RV-to-PA conduit placement.
178
What are long-term complications in survivors of pulmonary atresia?
Long-term issues include arrhythmias, reintervention for pulmonary artery stenosis, RV dysfunction, and complications from single-ventricle physiology if applicable.
179
What genetic syndromes are associated with pulmonary atresia?
Pulmonary atresia can be associated with 22q11 deletion (DiGeorge syndrome), Alagille syndrome, and other conotruncal abnormalities.
180
What is the prognosis of pulmonary atresia after surgical intervention?
Survival has improved dramatically with staged surgical approaches. Outcomes depend on pulmonary artery anatomy, RV development, and associated anomalies.
181
What is Hypoplastic Left Heart Syndrome (HLHS)?
HLHS is a congenital heart defect characterized by underdevelopment of the left-sided cardiac structures, leading to inadequate systemic blood flow.
182
What are the main anatomic features of HLHS?
Anatomic features include hypoplasia of the left ventricle, mitral and/or aortic valve atresia or stenosis, hypoplastic ascending aorta and aortic arch.
183
What is the embryological defect leading to HLHS?
HLHS results from failure of normal development of the left-sided heart structures during embryogenesis, possibly due to early outflow obstruction.
184
Why is systemic circulation duct-dependent in HLHS?
The systemic circulation depends on a PDA to supply blood from the pulmonary artery to the descending aorta because the left heart cannot sustain systemic output.
185
What intracardiac and extracardiac communications are crucial for survival in HLHS?
A patent foramen ovale or ASD is needed for oxygenated pulmonary venous blood to cross into the right atrium and mix before reaching systemic circulation.
186
What is the typical clinical presentation of HLHS in neonates?
Newborns with HLHS appear normal at birth but develop signs of shock, severe cyanosis, and respiratory distress as the ductus arteriosus begins to close.
187
What happens if the ductus arteriosus closes in a neonate with HLHS?
Ductus closure leads to profound systemic hypoperfusion, metabolic acidosis, multi-organ failure, and death if not urgently treated.
188
What are the physical examination findings in HLHS?
Findings include tachypnea, weak peripheral pulses, cool extremities, hepatomegaly, and differential cyanosis (lower body hypoxia).
189
What auscultatory findings are heard in HLHS?
There may be a single loud second heart sound (S2); a soft systolic murmur may be present if there is tricuspid regurgitation or PDA flow.
190
What are the chest X-ray findings in HLHS?
CXR typically shows cardiomegaly, pulmonary venous congestion, and increased pulmonary vascular markings due to elevated pulmonary blood flow.
191
What are the typical ECG findings in HLHS?
ECG shows right ventricular hypertrophy (RVH) and right axis deviation; there is absence of left ventricular forces.
192
What role does echocardiography play in diagnosing HLHS?
Echo confirms the diagnosis by showing hypoplastic LV, atretic or stenotic mitral/aortic valves, small ascending aorta, and ductal-dependent systemic flow.
193
What is the role of PGE1 in the acute management of HLHS?
PGE1 infusion maintains ductal patency, ensuring systemic perfusion until surgical intervention can be performed.
194
What are the initial medical management steps for HLHS in the newborn period?
Initial management includes stabilization with PGE1, ventilatory support if needed, correction of acidosis, and preparation for surgical intervention.
195
What are the surgical options for HLHS management?
Management options include staged surgical palliation (Norwood–Glenn–Fontan) or primary cardiac transplantation.
196
What are the stages of the Norwood procedure for HLHS?
The Norwood stages:
1. Norwood operation: create a new aorta and systemic outflow tract
2. Bidirectional Glenn shunt: SVC-to-PA connection
3. Fontan completion: IVC-to-PA connection.
197
What is the alternative to staged surgical palliation in HLHS?
Cardiac transplantation in the neonatal period is an alternative but is limited by donor availability and requires lifelong immunosuppression.
198
What are the long-term complications following HLHS surgery?
Long-term complications include arrhythmias, ventricular dysfunction, thromboembolism, protein-losing enteropathy, and need for heart transplantation later in life.
199
Which genetic syndromes are associated with HLHS?
HLHS is associated with Turner syndrome (XO), trisomy 18, trisomy 13, and other midline defects.
200
What is the overall prognosis for infants born with HLHS today?
With current surgical techniques, survival to adulthood is possible. 5-year survival after staged palliation is around 60–70% in specialized centers.
201
What is Ebstein Anomaly?
Ebstein anomaly is a congenital malformation characterized by apical displacement of the septal and posterior tricuspid valve leaflets into the right ventricle, resulting in 'atrialization' of part of the RV.
202
What is the embryological defect leading to Ebstein anomaly?
It arises from failure of proper delamination (separation) of the tricuspid valve leaflets from the myocardium during embryogenesis.
203
What are the characteristic anatomical features of Ebstein anomaly?
Key features include:
- Apical displacement of the septal and posterior tricuspid valve leaflets
- Redundant anterior leaflet
- Atrialized proximal RV
- Small functional RV.
204
How does Ebstein anomaly affect right heart function?
Reduced effective RV size and tricuspid regurgitation lead to decreased pulmonary blood flow and systemic venous congestion.
205
What is the pathophysiological impact of severe tricuspid regurgitation in Ebstein anomaly?
Severe tricuspid regurgitation results in massive right atrial enlargement, decreased pulmonary blood flow, cyanosis, and right heart failure.
206
What is the clinical spectrum of Ebstein anomaly presentation?
Presentation ranges from severe cyanosis and heart failure in neonates to mild symptoms or incidental murmur detection in older children/adults.
207
What are the typical symptoms in neonates with severe Ebstein anomaly?
Severely affected neonates present with profound cyanosis, tachypnea, hepatomegaly, cardiomegaly, and poor perfusion shortly after birth.
208
What are the symptoms of mild to moderate Ebstein anomaly presenting later in life?
Older patients may have exertional dyspnea, palpitations (due to arrhythmias), cyanosis, fatigue, or right-sided heart failure symptoms.
209
What are the characteristic physical examination findings in Ebstein anomaly?
Physical findings:
- Cyanosis (in severe cases)
- Split S1, widely split S2
- Holosystolic murmur of tricuspid regurgitation
- Jugular venous distension (older patients).
210
What auscultatory findings are heard in Ebstein anomaly?
A holosystolic murmur of tricuspid regurgitation is heard best at the left lower sternal border; may also hear wide splitting of S2.
211
What are the chest X-ray findings in Ebstein anomaly?
CXR findings include marked cardiomegaly (giant right atrium), decreased pulmonary vascular markings, and right atrial enlargement.
212
What are the characteristic ECG findings in Ebstein anomaly?
ECG findings include tall peaked P waves (right atrial enlargement), right bundle branch block (RBBB), and prolonged PR interval.
213
What arrhythmias are commonly associated with Ebstein anomaly?
Arrhythmias such as Wolff-Parkinson-White (WPW) syndrome, supraventricular tachycardia (SVT), and atrial fibrillation/flutter are common.
214
How is echocardiography used to diagnose Ebstein anomaly?
Echocardiography is diagnostic: it shows apical displacement of tricuspid leaflets >8 mm/m² body surface area, atrialized RV, and tricuspid regurgitation.
215
What is the significance of the 'atrialized' portion of the right ventricle in Ebstein anomaly?
The atrialized portion of the RV acts more like part of the right atrium, reducing effective RV contractility and worsening functional impairment.
216
What is the role of PGE1 infusion in neonates with critical Ebstein anomaly?
In neonates with duct-dependent pulmonary circulation, PGE1 infusion is used to maintain PDA and ensure pulmonary blood flow.
217
What are the initial medical management options for symptomatic neonates?
Management includes oxygen, PGE1 (if ductal-dependent), inotropic support, and treatment of arrhythmias or CHF if present.
218
What surgical options are available for Ebstein anomaly?
Surgical options include tricuspid valve repair (cone procedure), valve replacement, or single-ventricle palliation (Fontan) in extreme cases.
219
What factors determine the timing and type of surgery in Ebstein anomaly?
Timing depends on severity of symptoms, degree of tricuspid regurgitation, right heart function, and presence of arrhythmias.
220
What is the prognosis for patients with Ebstein anomaly?
Prognosis is highly variable: mild cases may live normal lives; severe cases require early surgery. Surgical advances (e.g., cone repair) have improved outcomes.
221
What is Coarctation of the Aorta?
Coarctation of the aorta is a congenital narrowing of a segment of the aorta, typically near the ductus arteriosus, leading to obstruction of systemic blood flow.
222
What are the two main types of coarctation based on anatomical location?
Types:
- Preductal (infantile type): narrowing before the ductus arteriosus
- Postductal (adult type): narrowing after the ductus arteriosus.
223
What is the embryological basis for coarctation of the aorta?
It results from abnormal development of the aortic arch during embryogenesis, possibly related to abnormal ductal tissue migration.
224
How does coarctation affect systemic and pulmonary circulation?
Narrowing increases left ventricular afterload, leading to hypertension proximal to the obstruction and decreased perfusion distally.
225
What are risk factors and associated conditions with coarctation of the aorta?
Risk factors/associations:
- Turner syndrome (XO)
- Bicuspid aortic valve
- Other left-sided obstructive lesions
- Berry aneurysms (brain).
226
How does coarctation of the aorta present in the neonatal period?
Neonates with critical coarctation present with shock, metabolic acidosis, and differential cyanosis (lower body hypoxia) as the PDA closes.
227
How does coarctation of the aorta present in older children and adults?
Older children present with hypertension (especially in upper extremities), headaches, claudication, epistaxis, or murmur found on routine exam.
228
What are typical physical examination findings in coarctation of the aorta?
Findings include upper extremity hypertension, diminished or delayed femoral pulses, and differential cyanosis if ductus is partially patent.
229
What blood pressure findings are suggestive of coarctation?
Blood pressure is elevated in the arms and decreased in the legs (arm-to-leg gradient >20 mmHg is significant).
230
What are the characteristic pulse findings in coarctation of the aorta?
Femoral pulses are weak and delayed compared to brachial pulses (brachiofemoral delay).
231
What are the auscultatory findings in coarctation of the aorta?
A systolic murmur best heard over the back (interscapular area) or left infrascapular area may be present.
232
What chest X-ray findings suggest coarctation of the aorta?
CXR findings:
- Rib notching (due to collateral vessels)
- Figure '3 sign' along the aortic shadow (pre- and post-stenotic dilations).
233
What ECG findings may be seen in coarctation of the aorta?
ECG may show left ventricular hypertrophy (LVH) due to pressure overload, especially in older children and adults.
234
What is the role of echocardiography in diagnosing coarctation?
Echo identifies the site and severity of narrowing, assesses LV function, detects associated cardiac anomalies (e.g., bicuspid aortic valve).
235
When is MRI or CT angiography used in coarctation evaluation?
MRI or CT angiography are used for detailed evaluation of aortic anatomy, especially in older patients and for surgical planning.
236
What is the role of PGE1 in neonatal coarctation management?
PGE1 infusion maintains ductal patency to ensure systemic perfusion in neonates with critical coarctation before surgery.
237
What are the indications for intervention in coarctation of the aorta?
Intervention is indicated for:
- Peak-to-peak gradient >20 mmHg
- Upper and lower limb blood pressure differential >20 mmHg
- Symptoms (e.g., CHF, hypertension).
238
What are the surgical options for repairing coarctation of the aorta?
Surgical options include end-to-end anastomosis, subclavian flap aortoplasty, patch aortoplasty, or extended arch reconstruction. Balloon angioplasty/stenting is used in some cases.
239
What are potential complications after coarctation repair?
Complications include re-coarctation, persistent hypertension, aneurysm formation at repair site, and aortic dissection (rare).
240
What is the long-term prognosis after coarctation of the aorta repair?
Most patients have excellent survival after repair, but lifelong follow-up is needed due to risk of hypertension and re-coarctation.
241
What is congenital Aortic Stenosis (AS)?
Congenital aortic stenosis is a narrowing at, above, or below the level of the aortic valve, causing obstruction to left ventricular outflow.
242
What are the anatomical types of aortic stenosis in congenital heart disease?
Types:
- Valvular (most common): bicuspid aortic valve with fusion of leaflets
- Subvalvular (membranous or muscular obstruction below the valve)
- Supravalvular (narrowing above the valve, e.g., Williams syndrome).
243
What is the pathophysiology of aortic stenosis?
Stenosis increases left ventricular afterload, leading to left ventricular hypertrophy, elevated LV pressures, decreased cardiac output, and risk of heart failure.
244
What embryological abnormality leads to congenital aortic stenosis?
Embryologically, abnormal valve development (e.g., bicuspid valve) or improper conotruncal septation can lead to aortic stenosis.
245
What are risk factors and associated conditions with congenital aortic stenosis?
Associated with:
- Bicuspid aortic valve (common)
- Coarctation of the aorta
- Williams syndrome (supravalvular AS)
- Turner syndrome (XO).
246
How does severe neonatal aortic stenosis present clinically?
Severe neonatal AS presents with critical left-sided obstruction after ductal closure: shock, poor perfusion, acidosis, tachypnea, and heart failure.
247
What are the clinical manifestations of mild to moderate congenital aortic stenosis in older children?
Older children may present with exertional chest pain, syncope, fatigue, exercise intolerance, or be asymptomatic with murmur detected incidentally.
248
What physical examination findings suggest aortic stenosis?
Findings include weak or delayed peripheral pulses, narrow pulse pressure, left ventricular heave, and signs of heart failure in severe cases.
249
What auscultatory features are characteristic of aortic stenosis?
A harsh systolic ejection murmur best heard at the right upper sternal border, radiating to the neck (carotids), is typical.
250
What is the significance of the timing of the murmur peak in aortic stenosis?
The later the murmur peaks in systole, the more severe the stenosis. Early-peaking murmurs indicate milder stenosis.
251
What are the chest X-ray findings in aortic stenosis?
CXR may show normal heart size or LV prominence, post-stenotic dilation of the ascending aorta, and pulmonary venous congestion in severe cases.
252
What are the ECG findings in aortic stenosis?
ECG shows left ventricular hypertrophy with strain pattern in moderate to severe cases (ST-T wave changes in left precordial leads).
253
How is echocardiography used to diagnose and assess aortic stenosis severity?
Echo identifies valve morphology, measures pressure gradients, assesses valve area, and evaluates LV function and hypertrophy.
254
What Doppler echocardiographic findings indicate severe aortic stenosis?
Peak gradient >64 mmHg (mean >40 mmHg) or valve area <0.7 cm²/m² indicates severe stenosis needing intervention.
255
When is cardiac catheterization indicated in aortic stenosis?
Cath is used when noninvasive imaging is inadequate or during planned balloon valvuloplasty intervention.
256
What are the indications for intervention in congenital aortic stenosis?
Intervention is indicated for:
- Symptomatic AS
- Peak gradient >64 mmHg or mean gradient >40 mmHg
- LV dysfunction or ST-T changes suggestive of strain.
257
What are the options for intervention in congenital aortic stenosis?
Options include balloon aortic valvuloplasty (preferred in children) or surgical aortic valve repair/replacement for severe dysplasia.
258
What is balloon valvuloplasty and when is it preferred?
Balloon valvuloplasty relieves obstruction by tearing fused commissures. Preferred in isolated valvular AS with pliable valves.
259
What are potential complications after intervention for aortic stenosis?
Complications include aortic regurgitation (after balloon), restenosis, LV dysfunction, and risk of sudden cardiac death if untreated.
260
What is the long-term prognosis for children with repaired congenital aortic stenosis?
Long-term outcome is good with appropriate interventions. Many require reintervention later for restenosis or valve replacement during adulthood.
261
What is Pulmonary Stenosis (PS)?
Pulmonary stenosis is an obstruction to blood flow from the right ventricle to the pulmonary artery due to narrowing at, above, or below the pulmonary valve.
262
What are the anatomical types of pulmonary stenosis?
Types:
- Valvular (most common)
- Subvalvular (infundibular)
- Supravalvular (main or branch pulmonary arteries).
263
What is the most common form of congenital pulmonary stenosis?
Valvular pulmonary stenosis is the most common form, often due to commissural fusion of the pulmonary valve leaflets.
264
What is the pathophysiology of pulmonary stenosis?
Obstruction increases right ventricular pressure, leading to right ventricular hypertrophy, right atrial enlargement, and reduced pulmonary blood flow if severe.
265
What syndromes are commonly associated with pulmonary stenosis?
Pulmonary stenosis is associated with Noonan syndrome, congenital rubella infection, and Williams syndrome (supravalvular PS).
266
What are the clinical features of mild pulmonary stenosis?
Mild pulmonary stenosis is usually asymptomatic and discovered incidentally on physical examination by hearing a murmur.
267
What are the symptoms of moderate to severe pulmonary stenosis?
Moderate to severe PS can present with exertional dyspnea, fatigue, chest pain, syncope, and eventually signs of right heart failure.
268
What physical examination findings suggest pulmonary stenosis?
Findings include a right ventricular heave, jugular venous distension (in severe cases), and possible hepatomegaly.
269
What are the auscultatory findings in pulmonary stenosis?
A harsh systolic ejection murmur heard best at the left upper sternal border, often associated with an ejection click that decreases with inspiration.
270
How does the timing of the murmur relate to stenosis severity?
The later the murmur peaks in systole, the more severe the stenosis. Early-peaking murmurs indicate milder disease.
271
What are chest X-ray findings in pulmonary stenosis?
CXR may show post-stenotic dilation of the main pulmonary artery and right ventricular enlargement in severe cases.
272
What ECG changes are seen in pulmonary stenosis?
ECG shows right axis deviation and right ventricular hypertrophy in moderate to severe cases; may be normal in mild cases.
273
What echocardiographic findings are diagnostic of pulmonary stenosis?
Echo identifies valve morphology, calculates pressure gradient, measures right ventricular size and function, and assesses post-stenotic dilation.
274
How is the severity of pulmonary stenosis graded by Doppler echocardiography?
Severity grading by Doppler:
- Mild: gradient <36 mmHg
- Moderate: 36–64 mmHg
- Severe: >64 mmHg.
275
When is cardiac catheterization indicated in pulmonary stenosis?
Cath is indicated for balloon valvuloplasty or when noninvasive imaging is inconclusive regarding anatomy or severity.
276
What are indications for intervention in pulmonary stenosis?
Intervention is indicated for:
- Severe PS (gradient >64 mmHg)
- Symptomatic moderate PS
- Progressive right ventricular dilation or dysfunction.
277
What is the preferred treatment for isolated valvular pulmonary stenosis?
Balloon pulmonary valvuloplasty is the first-line treatment for isolated valvular pulmonary stenosis without significant valve dysplasia.
278
How is balloon pulmonary valvuloplasty performed?
During cath, a balloon catheter is positioned across the valve and inflated to tear fused commissures, reducing obstruction.
279
What are potential complications following intervention for pulmonary stenosis?
Potential complications include pulmonary regurgitation, restenosis, arrhythmias, and injury to the pulmonary artery.
280
What is the long-term prognosis after treatment of pulmonary stenosis?
Long-term prognosis is excellent with appropriate intervention; most patients have normal exercise tolerance and quality of life.
281
What is Interrupted Aortic Arch (IAA)?
Interrupted aortic arch is a congenital defect where there is complete discontinuity between the ascending and descending aorta, disrupting systemic blood flow.
282
How is IAA classified anatomically?
Classified into:
- Type A: interruption distal to left subclavian artery
- Type B (most common): interruption between left carotid and left subclavian arteries
- Type C: interruption between innominate and left carotid arteries.
283
What embryological defect leads to interrupted aortic arch?
IAA results from abnormal regression of the fourth embryonic aortic arch, leading to separation of the proximal and distal aortic segments.
284
What is the pathophysiology of IAA?
Without continuity, systemic perfusion depends entirely on the ductus arteriosus; closure leads to profound hypoperfusion and shock.
285
Which congenital anomalies are commonly associated with IAA?
IAA is frequently associated with ventricular septal defect (VSD), patent ductus arteriosus (PDA), bicuspid aortic valve, and DiGeorge syndrome (22q11.2 deletion).
286
What are the clinical features of IAA in neonates?
Neonates present within the first days of life with signs of heart failure, respiratory distress, poor feeding, shock, and severe differential cyanosis.
287
What happens when the ductus arteriosus closes in IAA?
Closure of the ductus arteriosus causes abrupt cessation of blood flow to the lower body, resulting in acidosis, ischemia, and cardiovascular collapse.
288
What are the physical examination findings in IAA?
Physical exam shows weak or absent femoral pulses, differential cyanosis (upper extremities pink, lower extremities cyanotic), and signs of shock.
289
What are the auscultatory findings in IAA?
A loud single second heart sound is common. Murmurs vary depending on associated VSD or PDA; continuous murmurs may be present with PDA.
290
What chest X-ray findings may suggest IAA?
CXR may show cardiomegaly, increased pulmonary vascular markings, and absent aortic knob. Mediastinum may appear abnormal.
291
What are the ECG findings in interrupted aortic arch?
ECG shows right ventricular hypertrophy (RVH) due to pulmonary overcirculation and possibly LVH if significant VSD left-to-right shunting exists.
292
How does echocardiography help diagnose IAA?
Echo identifies arch interruption, VSD, PDA, and evaluates ventricular size and function. It is key for early diagnosis.
293
When is CT or MRI angiography needed in IAA evaluation?
CT angiography or MRI is needed for detailed evaluation of arch anatomy and pulmonary arteries preoperatively.
294
What is the role of PGE1 in IAA management?
PGE1 infusion maintains ductal patency and systemic perfusion until surgical repair can be performed.
295
What are the initial stabilization steps for neonates with IAA?
Stabilization includes starting PGE1, correcting acidosis, ventilatory support if necessary, and inotropic support if in shock.
296
What are the surgical options for repairing IAA?
Surgery involves direct end-to-end anastomosis of the aortic segments or using a patch; arch reconstruction may be needed.
297
What other cardiac repairs are typically performed along with arch repair?
VSD closure and PDA ligation or division are commonly performed simultaneously with arch repair.
298
What are common postoperative complications after IAA repair?
Complications include re-coarctation, residual VSD, persistent pulmonary hypertension, and recurrent arch obstruction.
299
What genetic syndrome is strongly associated with IAA?
DiGeorge syndrome (22q11.2 deletion) is strongly associated with IAA, especially type B interruption.
300
What is the long-term prognosis after surgical repair of IAA?
With early surgical repair and good perioperative management, survival approaches 85–90%, but lifelong surveillance for re-obstruction is needed.
301
What is Mitral Valve Prolapse (MVP)?
MVP is a condition where one or both mitral valve leaflets prolapse (bulge) into the left atrium during systole, sometimes causing mitral regurgitation.
302
What are the structural abnormalities in MVP?
Structural abnormalities include myxomatous degeneration, redundant leaflets, elongated chordae tendineae, and annular dilation.
303
What are primary vs secondary causes of MVP?
Primary MVP is due to intrinsic valve pathology (e.g., myxomatous degeneration); secondary MVP is associated with other conditions like ischemic heart disease or cardiomyopathies.
304
What is the pathophysiology of MVP?
Prolapse causes abnormal tension on chordae, leading to incomplete leaflet coaptation and potential mitral regurgitation.
305
Which connective tissue disorders are associated with MVP?
Connective tissue disorders associated with MVP include Marfan syndrome, Ehlers-Danlos syndrome, and osteogenesis imperfecta.
306
What is the prevalence of MVP in the general population?
MVP occurs in approximately 2–3% of the general population, with a slight female predominance.
307
What are the typical symptoms of MVP?
Symptoms may include atypical chest pain, palpitations, fatigue, dyspnea, dizziness, or anxiety. Many patients are asymptomatic.
308
What are the physical examination findings in MVP?
Physical findings include a mid-systolic click followed by a late systolic murmur heard best at the apex.
309
What auscultatory features are characteristic of MVP?
The mid-systolic click results from sudden tensing of redundant chordae or leaflet tissue; the murmur represents mitral regurgitation if present.
310
How does the timing of the click or murmur in MVP change with maneuvers?
Standing or Valsalva maneuver (reducing preload) makes the click/murmur occur earlier; squatting (increasing preload) delays the click/murmur.
311
What are the ECG findings in MVP?
ECG may be normal or show nonspecific ST-T wave changes, particularly in the inferior leads. Arrhythmias (e.g., PVCs) may also be seen.
312
What are the echocardiographic diagnostic criteria for MVP?
Echo diagnosis: leaflet displacement >2 mm into the left atrium during systole and thickened leaflets (>5 mm) in classic MVP.
313
What complications can arise from MVP?
Complications include significant mitral regurgitation, infective endocarditis, arrhythmias (e.g., atrial or ventricular ectopy), and rarely sudden cardiac death.
314
What is the risk of infective endocarditis in MVP?
The risk of infective endocarditis is low unless there is associated significant mitral regurgitation or prior history of endocarditis.
315
What are the indications for surgical repair in MVP?
Surgical repair is indicated for severe mitral regurgitation causing symptoms, LV dysfunction (EF <60% or LVESD >40 mm), or new-onset atrial fibrillation.
316
What medical management is indicated for symptomatic MVP without significant MR?
Beta-blockers are used for symptomatic palpitations, chest pain, or anxiety-like symptoms in MVP without significant MR.
317
What are the surgical options for MVP with severe mitral regurgitation?
Surgical options include mitral valve repair (preferred) or valve replacement if repair is not feasible.
318
How does MVP in Marfan syndrome differ from isolated MVP?
In Marfan syndrome, MVP occurs earlier, progresses more rapidly, and is more commonly associated with significant regurgitation and risk of aortic pathology.
319
What lifestyle recommendations are given to patients with MVP?
Patients should maintain good hydration, avoid excessive caffeine or stimulants, and exercise according to tolerance unless severe MR is present.
320
What is the overall prognosis for isolated MVP?
Isolated MVP without significant MR has an excellent long-term prognosis, with minimal risk of complications in the majority of cases.
321
What is Single Ventricle Physiology?
Single ventricle physiology refers to congenital heart defects where only one functional ventricular chamber is available to support systemic and pulmonary circulations.
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What are common congenital defects resulting in single ventricle physiology?
Common defects include tricuspid atresia, hypoplastic left heart syndrome, double inlet left ventricle, unbalanced AV canal defects, and some forms of DORV.
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What is the pathophysiological hallmark of single ventricle physiology?
The hallmark is complete mixing of oxygenated and deoxygenated blood in the single ventricle, leading to systemic desaturation and volume overload.
324
How does systemic and pulmonary blood flow interact in single ventricle circulation?
Both systemic and pulmonary circulations are supplied in parallel from a single ventricle, competing for limited cardiac output.
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Why is balancing pulmonary and systemic blood flow critical in single ventricle patients?
Excessive pulmonary blood flow steals from systemic perfusion (shock), whereas inadequate pulmonary flow causes profound hypoxia. Balance is essential for survival.
326
What are the clinical features of single ventricle physiology in neonates?
Neonates present with cyanosis, tachypnea, poor feeding, failure to thrive, signs of heart failure, and often shock if flows are not balanced.
327
What role does a patent ductus arteriosus (PDA) play in single ventricle physiology?
PDA maintains pulmonary or systemic blood flow depending on specific anatomy, especially in defects with duct-dependent pulmonary or systemic circulation.
328
What are the physical exam findings in neonates with single ventricle physiology?
Findings include cyanosis, weak peripheral pulses, tachypnea, hepatomegaly, and signs of volume overload (increased precordial activity).
329
What echocardiographic features are evaluated in single ventricle anatomy?
Echo assesses ventricular morphology, valve anatomy, atrioventricular and ventriculoarterial connections, outflow tract obstruction, and arch anatomy.
330
When is cardiac catheterization indicated in single ventricle evaluation?
Cardiac catheterization evaluates pulmonary vascular resistance, anatomy, and candidacy for staged surgical palliation (especially before Glenn or Fontan).
331
What is the role of PGE1 infusion in management of single ventricle neonates?
PGE1 maintains ductal patency to ensure balanced systemic and pulmonary blood flow until staged surgery can be performed.
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What is the typical staged surgical approach for single ventricle physiology?
Surgical palliation includes:
1. Norwood procedure (neonatal period)
2. Bidirectional Glenn (4–6 months)
3. Fontan completion (2–4 years).
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What is the goal of the Norwood procedure?
Norwood procedure reconstructs the aortic arch and establishes reliable systemic output using the single ventricle.
334
What is the purpose of the Bidirectional Glenn procedure?
The Glenn connects the superior vena cava directly to the pulmonary arteries, reducing volume load on the ventricle and improving oxygenation.
335
What is the Fontan procedure and what does it achieve?
Fontan connects systemic venous return (inferior vena cava) directly to pulmonary arteries, bypassing the heart for passive pulmonary flow.
336
What are common complications after Fontan completion?
Complications include arrhythmias, thromboembolism, protein-losing enteropathy, hepatic congestion and fibrosis, plastic bronchitis, and heart failure.
337
What is protein-losing enteropathy and how is it related to Fontan physiology?
Protein-losing enteropathy results from elevated systemic venous pressures, causing intestinal protein leakage and hypoalbuminemia.
338
What arrhythmias are common in single ventricle survivors?
Common arrhythmias include atrial flutter, atrial fibrillation, junctional rhythms, and ventricular tachycardia in late survivors.
339
Which genetic syndromes are commonly associated with single ventricle anatomy?
Associated syndromes include heterotaxy, asplenia or polysplenia syndromes, and some forms of DiGeorge syndrome (22q11.2 deletion).
340
What is the overall prognosis for single ventricle patients after Fontan surgery?
Fontan survival has improved, with 20-year survival rates >80% in modern cohorts. However, significant late morbidity remains common.
341
What is Double Outlet Right Ventricle (DORV)?
Double Outlet Right Ventricle (DORV) is a congenital heart defect in which both the aorta and pulmonary artery arise predominantly from the right ventricle.
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What is the pathophysiology of DORV?
DORV results in varying degrees of mixing of systemic and pulmonary circulations, depending on the VSD location and presence of pulmonary or aortic outflow obstruction.
343
What are the types of DORV based on VSD location?
Types based on VSD location:
- Subaortic VSD
- Subpulmonary VSD (Taussig-Bing anomaly)
- Doubly committed VSD
- Noncommitted (remote) VSD.
344
How does the location of the VSD influence clinical presentation in DORV?
Subaortic VSD resembles physiology of VSD; subpulmonary VSD resembles transposition physiology (TGA-like). Remote VSD leads to complex physiology requiring staged repair.
345
What are the common clinical features of DORV in neonates?
Neonates may present with cyanosis, heart failure symptoms, failure to thrive, or a combination depending on the anatomy and flow patterns.
346
What symptoms appear in DORV with subaortic VSD?
Subaortic VSD: presents similarly to isolated VSD with signs of pulmonary overcirculation (tachypnea, poor feeding, failure to thrive).
347
What symptoms appear in DORV with subpulmonary VSD (Taussig-Bing anomaly)?
Subpulmonary VSD (Taussig-Bing anomaly): presents with severe cyanosis due to physiology similar to TGA (parallel circulations).
348
What physical examination findings suggest DORV?
Findings include cyanosis, tachypnea, signs of congestive heart failure, active precordium, and hepatomegaly if heart failure is present.
349
What are the auscultatory findings in DORV?
A harsh holosystolic murmur from the VSD is often heard; if pulmonary stenosis is present, a systolic ejection murmur may also be noted.
350
What are the chest X-ray findings in DORV?
CXR shows cardiomegaly with increased pulmonary vascular markings in subaortic VSD; in Taussig-Bing, heart may appear egg-shaped like TGA.
351
What are the ECG findings in DORV?
ECG findings are nonspecific but may show biventricular hypertrophy or right ventricular hypertrophy depending on the flow dynamics.
352
What echocardiographic features help diagnose DORV?
Echo defines the VSD location, outflow tract anatomy, relationship of great vessels, presence of PS, and ventricular function.
353
When is cardiac MRI or CT angiography used in DORV?
MRI or CT angiography is used to assess pulmonary artery anatomy, arch anomalies, and detailed spatial relationships when Echo is insufficient.
354
What is the role of cardiac catheterization in DORV management?
Cath is used to define pressures, pulmonary vascular resistance, and anatomy if noninvasive imaging is inconclusive or before surgery.
355
What is the general approach to surgical management of DORV?
Management depends on anatomy but typically involves early surgical repair directed toward routing blood appropriately through the VSD.
356
What surgical procedure is done for DORV with subaortic VSD and mild PS?
For DORV with subaortic VSD and no significant PS, surgical VSD closure and rerouting blood to the aorta is performed (intra-ventricular tunnel).
357
What surgical procedure is preferred for DORV with subpulmonary VSD (Taussig-Bing anomaly)?
In DORV with subpulmonary VSD (Taussig-Bing), an arterial switch operation (ASO) with VSD closure is typically required.
358
When is a Rastelli procedure indicated in DORV?
Rastelli procedure is used for DORV with subaortic VSD and significant PS: VSD is patched to aorta, and RV is connected to PA via conduit.
359
What are common complications after DORV repair?
Postoperative complications include residual VSD, conduit obstruction (if used), arrhythmias, and ventricular dysfunction.
360
What is the long-term prognosis after DORV surgical repair?
Long-term prognosis is generally good with appropriate repair but may require reoperations for conduit replacement or residual lesions.
