CVS2 Flashcards
1
Q
What is Anomalous Left Coronary Artery from the Pulmonary Artery (ALCAPA)?
A
ALCAPA is a rare congenital coronary anomaly where the left coronary artery originates abnormally from the pulmonary artery instead of the aorta.
2
Q
What is the pathophysiology of ALCAPA?
A
Blood from the pulmonary artery is poorly oxygenated and low-pressure postnatally, leading to myocardial ischemia and infarction in the left heart.
3
Q
What are the two clinical forms of ALCAPA?
A
Two forms:
- Infantile type: early heart failure and ischemia
- Adult type: survival via collateral development but at risk of sudden death.
4
Q
When do symptoms typically appear in infants with ALCAPA?
A
Symptoms typically begin between 1–2 months of age as pulmonary artery pressure falls and oxygen delivery to myocardium worsens.
5
Q
What are the classic clinical features of infantile ALCAPA?
A
Infants present with poor feeding, diaphoresis, tachypnea, irritability, failure to thrive, and signs of heart failure (CHF).
6
Q
What are the signs of heart failure in ALCAPA?
A
Signs of CHF include tachypnea, hepatomegaly, diaphoresis with feeds, poor weight gain, and pallor.
7
Q
Why do infants with ALCAPA develop ischemia after birth?
A
After birth, pulmonary artery pressure falls, causing low perfusion pressure in the left coronary system, resulting in ischemia and infarction.
8
Q
What is the role of collateral circulation in ALCAPA?
A
Extensive right coronary to left coronary collaterals may develop; however, this can cause a coronary steal phenomenon worsening ischemia.
9
Q
What physical examination findings suggest ALCAPA?
A
Physical findings include signs of heart failure, weak pulses, gallop rhythm (S3), and sometimes a murmur of mitral regurgitation.
10
Q
What murmur is often heard in ALCAPA?
A
A pansystolic murmur of mitral regurgitation may be heard at the apex due to papillary muscle ischemia.
11
Q
What are the chest X-ray findings in ALCAPA?
A
CXR shows cardiomegaly and pulmonary edema typical of heart failure.
12
Q
What are the ECG findings suggestive of ALCAPA?
A
ECG shows deep Q waves in leads I and aVL, ST-segment depression, and signs of anterolateral myocardial infarction.
13
Q
How is echocardiography used to diagnose ALCAPA?
A
Echo may show a dilated right coronary artery, abnormal flow into the pulmonary artery, poor LV function, and mitral regurgitation.
14
Q
What Doppler findings support the diagnosis of ALCAPA?
A
Color Doppler may show retrograde flow from the left coronary artery into the pulmonary artery.
15
Q
When is cardiac catheterization or CT/MRI angiography needed in ALCAPA?
A
CT angiography, MRI, or cardiac catheterization are used to confirm the anatomy if echocardiographic diagnosis is uncertain.
16
Q
What is the definitive treatment for ALCAPA?
A
Definitive treatment is surgical correction to restore a two-coronary artery system supplying the myocardium with oxygenated blood.
17
Q
What are the surgical options for repairing ALCAPA?
A
Options include direct reimplantation of the left coronary artery into the aorta (preferred) or coronary artery bypass grafting (CABG) in older children.
18
Q
What are potential complications after ALCAPA repair?
A
Complications post-repair include persistent LV dysfunction, arrhythmias, mitral regurgitation, and very rarely coronary re-occlusion.
19
Q
What is the prognosis if ALCAPA is left untreated?
A
Without treatment, up to 90% of infants with ALCAPA die within the first year of life due to myocardial infarction and heart failure.
20
Q
What is the long-term prognosis after successful surgical repair of ALCAPA?
A
With timely surgical repair, long-term survival is excellent, though ventricular function recovery varies depending on preoperative damage.
21
Q
What is Congenitally Corrected Transposition of the Great Arteries (l-TGA)?
A
l-TGA (levo-TGA) is a congenital heart defect with atrioventricular and ventriculoarterial discordance, resulting in physiologically corrected blood flow but abnormal ventricular workload.
22
Q
How does l-TGA differ from d-TGA?
A
In d-TGA, blood circulates in parallel without mixing unless there is a shunt; in l-TGA, blood circulates normally but with ventricles and valves switched.
23
Q
What is the pathophysiology of l-TGA?
A
The morphologic right ventricle supports systemic circulation, leading to eventual RV failure and tricuspid valve regurgitation.
24
Q
What embryological defect leads to l-TGA?
A
l-TGA results from abnormal looping of the heart tube to the left (instead of right) during embryogenesis, altering chamber connections.
25
What is meant by atrioventricular and ventriculoarterial discordance in l-TGA?
Atrioventricular discordance: right atrium connects to morphologic left ventricle.
Ventriculoarterial discordance: left ventricle connects to pulmonary artery.
26
What are the common associated cardiac anomalies with l-TGA?
Associated anomalies:
- VSD (most common)
- Pulmonary stenosis
- Tricuspid valve abnormalities (Ebstein-like)
- Complete heart block.
27
What are the typical clinical features of isolated l-TGA?
Isolated l-TGA may remain asymptomatic into adulthood but may later develop heart failure, arrhythmias, or tricuspid regurgitation.
28
When do symptoms usually develop in l-TGA patients?
Symptoms usually develop in adolescence or adulthood, especially heart failure symptoms or syncope due to heart block.
29
What physical exam findings are suggestive of l-TGA with associated lesions?
Findings may include cyanosis (if VSD/PS), heart failure signs, and bradycardia if complete heart block develops.
30
What murmurs are commonly heard in l-TGA?
Murmurs may include holosystolic murmur of VSD or tricuspid regurgitation; ejection murmurs if pulmonary stenosis is present.
31
What are the ECG findings typical of l-TGA?
ECG shows absence of normal Q waves in left precordial leads, upright T waves in V1, and possible complete heart block.
32
What are the chest X-ray findings in l-TGA?
CXR may show a normal-sized heart or mild cardiomegaly; great vessels may appear abnormally positioned (straight or leftward aorta).
33
What echocardiographic features help diagnose l-TGA?
Echo confirms atrioventricular and ventriculoarterial discordance, assesses RV and LV function, and detects associated defects.
34
When is cardiac MRI or CT angiography indicated in l-TGA?
MRI or CT angiography is used to better define complex anatomy and assess systemic RV function in adolescents/adults.
35
What is the long-term risk associated with systemic right ventricle in l-TGA?
The systemic RV may eventually fail because it is not built to handle systemic pressures long-term.
36
What is the natural history of tricuspid valve in l-TGA?
The tricuspid valve often develops regurgitation over time, leading to worsening systemic RV failure.
37
What are the indications for surgical intervention in l-TGA?
Intervention is indicated for significant tricuspid regurgitation, heart failure, arrhythmias, or progressive systemic RV dysfunction.
38
What are the surgical options for l-TGA correction?
Options include physiologic repair (VSD/PS repair) or anatomic correction (double-switch procedure).
39
What is the double-switch procedure in l-TGA?
The double-switch procedure combines an atrial switch (Mustard/Senning) with an arterial switch, putting the LV back in systemic position.
40
What is the prognosis for l-TGA patients after surgical correction?
Prognosis is good after double-switch surgery if performed before significant systemic RV or tricuspid valve dysfunction develops.
41
What is Atrioventricular Septal Defect (AVSD)?
AVSD is a congenital heart defect characterized by deficiency of the atrioventricular septum, leading to communication between all four chambers and a common AV valve.
42
What embryological defect leads to AVSD?
AVSD results from failure of endocardial cushion fusion during embryogenesis, affecting both atrial and ventricular septa and AV valves.
43
What are the two main types of AVSD?
Types:
- Complete AVSD: single common AV valve and combined ASD + VSD.
- Partial (or incomplete) AVSD: primum ASD + cleft mitral valve.
44
What structures are involved in a complete AVSD?
Complete AVSD involves a primum ASD, inlet VSD, and a common AV valve connecting both atria and ventricles.
45
What structures are involved in a partial AVSD?
Partial AVSD includes a primum ASD and a cleft mitral valve but with separate left and right AV valves (no VSD).
46
Which chromosomal syndrome is most strongly associated with AVSD?
AVSD is highly associated with Down syndrome (trisomy 21), especially complete AVSD.
47
What is the typical clinical presentation of complete AVSD in infants?
Complete AVSD typically presents at 6–8 weeks with signs of heart failure: tachypnea, poor feeding, failure to thrive, and recurrent respiratory infections.
48
What symptoms appear in partial AVSD?
Partial AVSD often presents later with symptoms of mitral regurgitation, including exercise intolerance, fatigue, and sometimes cyanosis if pulmonary hypertension develops.
49
What physical examination findings suggest AVSD?
Findings include tachypnea, hepatomegaly, active precordium, a loud S2, and murmurs of AV valve regurgitation or flow murmurs from increased pulmonary flow.
50
What murmurs are commonly heard in AVSD?
Murmurs include holosystolic murmur of mitral/tricuspid regurgitation and mid-diastolic rumble at the apex due to increased flow across the AV valves.
51
What are the chest X-ray findings in complete AVSD?
CXR shows cardiomegaly, increased pulmonary vascular markings, and sometimes right-sided aortic arch.
52
What are the ECG findings suggestive of AVSD?
ECG shows superior QRS axis deviation (left axis deviation), first-degree AV block (prolonged PR), and signs of biatrial enlargement.
53
What echocardiographic features confirm the diagnosis of AVSD?
Echo shows primum ASD, inlet VSD (if complete), common AV valve, and assesses valve regurgitation and chamber enlargement.
54
What associated defects are commonly seen with AVSD?
Associated anomalies include left superior vena cava draining to coronary sinus, right aortic arch, and pulmonary hypertension.
55
When is cardiac catheterization indicated in AVSD?
Cath is indicated if pulmonary vascular resistance needs assessment prior to repair, especially if diagnosis is delayed.
56
What is the natural history of untreated complete AVSD?
Untreated complete AVSD leads to irreversible pulmonary vascular obstructive disease (Eisenmenger syndrome) and early death.
57
When is surgical repair indicated for AVSD?
Surgical repair is indicated between 3–6 months of age for complete AVSD and at 2–4 years for partial AVSD with significant regurgitation.
58
What does surgical repair of AVSD involve?
Repair involves patch closure of septal defects and reconstruction of AV valves into two competent valves (left and right).
59
What are potential postoperative complications of AVSD repair?
Post-op complications include residual AV valve regurgitation, left ventricular outflow tract obstruction, arrhythmias (heart block), and reoperation.
60
What is the long-term prognosis after AVSD repair?
With early surgical repair, long-term survival is excellent (>85%), but ongoing valve dysfunction and arrhythmias require lifelong follow-up.
61
What is Patent Foramen Ovale (PFO)?
PFO is a persistent communication between the right and left atria through the foramen ovale that fails to close after birth.
62
What is the embryological basis for the formation of the foramen ovale?
The foramen ovale forms from the overlap of the septum primum and septum secundum during fetal development, allowing right-to-left shunting of blood.
63
What normally happens to the foramen ovale after birth?
After birth, increased left atrial pressure usually forces the septa to fuse, functionally and anatomically closing the foramen ovale.
64
What causes persistence of a PFO?
Persistence occurs when incomplete fusion of the septum primum and secundum allows intermittent or continuous communication between atria.
65
How common is PFO in the general population?
PFO is present in about 25–30% of the general population, often remaining clinically silent.
66
What is the pathophysiological significance of a PFO?
PFO can serve as a conduit for paradoxical embolism, allowing venous thrombi to bypass the pulmonary circulation and enter systemic arteries.
67
What are the clinical symptoms associated with PFO in children?
PFO is usually asymptomatic in children; however, it may contribute to stroke, migraine with aura, decompression sickness, or platypnea-orthodeoxia syndrome.
68
What role does PFO play in cryptogenic stroke?
In cryptogenic strokes (stroke of unknown cause), a significant proportion of cases, especially in young adults, are associated with PFO.
69
What other conditions are associated with PFO?
Conditions associated with PFO include migraine with aura, systemic embolism, decompression illness in divers, and rarely hypoxemia syndromes.
70
What are physical examination findings in isolated PFO?
Physical examination is typically normal in isolated PFO without associated structural heart disease or significant shunt.
71
How is PFO detected on echocardiography?
Transthoracic echocardiography (TTE) with color Doppler can detect PFO by observing intermittent left-to-right or right-to-left shunting.
72
What is the role of contrast (bubble) study in PFO diagnosis?
Contrast echocardiography (bubble study) involves injecting agitated saline into a vein and observing bubbles crossing from right to left atrium.
73
How can transesophageal echocardiography (TEE) assist in PFO evaluation?
TEE provides higher-resolution imaging of the atrial septum and is more sensitive than TTE for detecting small PFOs.
74
What is the difference between PFO and ASD on echocardiography?
In ASD, a true anatomical deficiency in septal tissue is seen, while in PFO the septa are intact but not fully fused, leading to a flap-like opening.
75
When is PFO closure indicated?
Closure is indicated in patients with cryptogenic stroke, platypnea-orthodeoxia syndrome, or recurrent systemic embolism despite anticoagulation.
76
What are the options for PFO closure?
Options include percutaneous device closure (Amplatzer or Gore devices) or rarely surgical closure if concomitant heart surgery is needed.
77
What are the potential complications of PFO device closure?
Complications include device embolization, atrial arrhythmias (e.g., atrial fibrillation), device thrombosis, and rare erosion of atrial wall.
78
What are the conservative management options for PFO in asymptomatic patients?
Asymptomatic patients are usually managed conservatively with observation or, if indicated, medical therapy (antiplatelet or anticoagulation).
79
How does Valsalva maneuver help in PFO detection?
Valsalva maneuver increases right atrial pressure transiently, promoting right-to-left shunting and improving PFO detection on echo studies.
80
What is the long-term prognosis for individuals with a PFO?
Most individuals with isolated PFO remain asymptomatic with normal lifespan; closure reduces risk of recurrent stroke in selected patients.
81
What is the definition of heart failure in children?
Heart failure in children is the inability of the heart to pump blood adequately to meet the body's metabolic demands or only at the expense of elevated filling pressures.
82
What are the primary causes of heart failure in neonates?
Common causes in neonates include structural heart defects (e.g., critical coarctation, hypoplastic left heart syndrome) and myocardial dysfunction (e.g., myocarditis, cardiomyopathy).
83
What are the primary causes of heart failure in infants and children?
In older infants and children, causes include left-to-right shunt lesions (e.g., VSD, PDA), cardiomyopathy, myocarditis, and arrhythmias.
84
How does heart failure in children differ from that in adults?
Unlike adults where ischemic disease predominates, heart failure in children is usually due to congenital heart disease or primary myocardial disease.
85
What are the types of heart failure based on ventricular function?
Types:
- Systolic heart failure (reduced contractility)
- Diastolic heart failure (impaired ventricular filling or compliance).
86
What are the common clinical signs of heart failure in infants?
Signs in infants: tachypnea, diaphoresis during feeding, poor feeding, poor weight gain, hepatomegaly, and irritability.
87
What are the common clinical signs of heart failure in older children?
Signs in older children: exercise intolerance, dyspnea on exertion, fatigue, abdominal pain, orthopnea, and edema.
88
What are the systemic symptoms of heart failure in children?
Systemic symptoms include poor growth, cold extremities, abdominal distention from hepatomegaly, and decreased urine output.
89
What are the key physical examination findings in pediatric heart failure?
Exam findings: tachycardia, tachypnea, hepatomegaly, gallop rhythm (S3), murmur (if structural lesion), peripheral edema, and poor perfusion.
90
What are the signs of low cardiac output in children?
Signs of low output: cool extremities, weak pulses, prolonged capillary refill (>3 seconds), hypotension, and altered mental status.
91
How is chest X-ray helpful in evaluating heart failure in children?
Chest X-ray may show cardiomegaly, pulmonary venous congestion, pleural effusions, and increased pulmonary vascular markings.
92
What are the typical ECG findings in pediatric heart failure?
ECG may show tachycardia, ventricular hypertrophy patterns, arrhythmias, or signs of ischemia depending on cause.
93
What role does echocardiography play in pediatric heart failure diagnosis?
Echo assesses ventricular systolic and diastolic function, detects structural defects, measures pressures, and identifies pericardial effusions.
94
What blood tests are useful in evaluating pediatric heart failure?
Useful blood tests: electrolytes, renal function, liver function tests, troponins (if myocarditis suspected), BNP, and NT-proBNP.
95
What is the role of BNP and NT-proBNP in pediatric heart failure?
BNP and NT-proBNP are elevated in heart failure and correlate with severity; they are useful for diagnosis and monitoring treatment response.
96
What are the goals of heart failure treatment in children?
Goals: improve oxygen delivery, decrease cardiac workload, manage fluid balance, control symptoms, and treat underlying cause.
97
What medications are used to treat heart failure in children?
Medications include diuretics (furosemide), ACE inhibitors (captopril, enalapril), beta-blockers (carvedilol in select cases), and aldosterone antagonists (spironolactone).
98
What is the role of diuretics in pediatric heart failure?
Diuretics reduce preload and pulmonary congestion but must be used cautiously to avoid hypovolemia and electrolyte disturbances.
99
When is mechanical circulatory support considered in pediatric heart failure?
Mechanical support (e.g., ECMO, VAD) is considered in severe refractory heart failure, often as a bridge to recovery or heart transplantation.
100
What is the prognosis of heart failure in children based on etiology?
Prognosis depends on etiology: structural defects corrected early have good outcomes; dilated cardiomyopathy has variable prognosis with risk of transplant in severe cases.
101
What is myocarditis?
Myocarditis is inflammation of the myocardium (heart muscle) that can lead to ventricular dysfunction, arrhythmias, and heart failure.
102
What are the common infectious causes of myocarditis in children?
Common infectious causes: enteroviruses (e.g., coxsackie B), adenovirus, parvovirus B19, influenza, SARS-CoV-2, and bacterial infections (e.g., Lyme disease).
103
What are non-infectious causes of myocarditis?
Non-infectious causes include autoimmune diseases (e.g., SLE, Kawasaki disease), drug reactions, toxins, and post-viral immune-mediated injury.
104
What is the pathophysiology of myocarditis?
Infection or inflammation causes direct myocyte injury and triggers immune-mediated myocardial damage, leading to ventricular dysfunction.
105
What are the classic clinical features of myocarditis in infants?
Infants often present with feeding difficulties, tachypnea, lethargy, irritability, poor perfusion, and signs of acute heart failure.
106
What are the clinical features of myocarditis in older children and adolescents?
Older children and adolescents present with chest pain, palpitations, syncope, exercise intolerance, and symptoms of heart failure.
107
What are the common signs of myocarditis on physical examination?
Physical findings: tachycardia disproportionate to fever, gallop rhythm (S3/S4), hepatomegaly, hypotension, poor perfusion, and arrhythmias.
108
What are the early warning signs of fulminant myocarditis?
Early warning signs of fulminant myocarditis include profound hypotension, refractory arrhythmias, severe heart failure, and sudden cardiovascular collapse.
109
What ECG findings may suggest myocarditis?
ECG may show sinus tachycardia, ST-T wave changes (e.g., diffuse ST elevation or depression), low voltage, or arrhythmias (e.g., ventricular ectopy).
110
What chest X-ray findings are seen in myocarditis?
CXR may reveal cardiomegaly, pulmonary edema, pleural effusions, or signs of heart failure.
111
What is the role of echocardiography in diagnosing myocarditis?
Echo shows global ventricular dysfunction, reduced ejection fraction, chamber dilation, and sometimes pericardial effusion.
112
What laboratory tests are helpful in evaluating myocarditis?
Helpful labs: troponins (elevated in myocyte injury), BNP/NT-proBNP (elevated in heart failure), inflammatory markers (CRP, ESR), viral PCRs.
113
What is the role of cardiac MRI in myocarditis diagnosis?
Cardiac MRI can detect myocardial edema, hyperemia, fibrosis (late gadolinium enhancement), and help confirm myocarditis noninvasively.
114
When should endomyocardial biopsy be considered in myocarditis?
Endomyocardial biopsy is considered in severe or refractory cases to guide therapy, especially if giant cell myocarditis or other specific pathology is suspected.
115
What are the main differential diagnoses for myocarditis?
Differentials include dilated cardiomyopathy, sepsis with cardiac dysfunction, Kawasaki disease, pulmonary embolism, and anomalous coronary arteries.
116
What supportive care measures are important in myocarditis management?
Supportive care includes oxygen, fluid and electrolyte management, inotropes if needed, monitoring for arrhythmias, and intensive care if severe.
117
What pharmacologic treatments are used in myocarditis?
Medications: inotropes (e.g., milrinone, dobutamine), diuretics for heart failure, ACE inhibitors for afterload reduction; immunosuppression is controversial.
118
When is mechanical circulatory support indicated in myocarditis?
Mechanical support (ECMO, VAD) is indicated in cardiogenic shock unresponsive to medical therapy or as bridge to recovery/transplant.
119
What are potential complications of myocarditis?
Complications include cardiogenic shock, severe arrhythmias (ventricular tachycardia/fibrillation), dilated cardiomyopathy, and sudden cardiac death.
120
What is the prognosis of pediatric myocarditis?
Prognosis varies: many recover fully, but some progress to chronic heart failure or require transplant; fulminant cases have higher mortality but may recover if supported.
121
What is Dilated Cardiomyopathy (DCM)?
DCM is a myocardial disorder characterized by dilation and impaired contraction of the left or both ventricles, leading to systolic dysfunction.
122
What are the primary causes of DCM in children?
Primary causes include idiopathic DCM, familial/genetic cardiomyopathy, and post-viral myocarditis.
123
What are the secondary causes of DCM?
Secondary causes include neuromuscular disorders (e.g., Duchenne muscular dystrophy), nutritional deficiencies (e.g., selenium, thiamine), toxins (e.g., chemotherapy), and systemic diseases.
124
What is the pathophysiology of DCM?
Dilation of the ventricles leads to impaired systolic function, increased end-diastolic pressure, pulmonary congestion, and eventually heart failure.
125
What are common genetic conditions associated with DCM?
Genetic syndromes associated with DCM include Duchenne and Becker muscular dystrophies, Barth syndrome, and various sarcomeric protein mutations.
126
What are the typical clinical features of DCM in infants?
Infants present with feeding difficulties, tachypnea, poor weight gain, hepatomegaly, and failure to thrive.
127
What symptoms are seen in older children with DCM?
Older children may present with exertional dyspnea, fatigue, exercise intolerance, palpitations, and signs of heart failure.
128
What are the common signs of DCM on physical examination?
Exam findings: tachycardia, hepatomegaly, gallop rhythm (S3), murmurs of mitral or tricuspid regurgitation, and peripheral edema.
129
What is the hallmark chest X-ray finding in DCM?
CXR shows cardiomegaly with or without pulmonary edema, pleural effusions, or pulmonary venous congestion.
130
What ECG findings are typical in DCM?
ECG often shows sinus tachycardia, low QRS voltages, left bundle branch block, or ventricular arrhythmias.
131
What does echocardiography reveal in DCM?
Echo shows globally dilated chambers, reduced ejection fraction, mitral regurgitation, and normal or thinned ventricular walls.
132
What laboratory investigations are useful in evaluating DCM?
Labs include BNP/NT-proBNP (elevated), troponin (may be elevated if active injury), viral panels, and metabolic/genetic testing when indicated.
133
What is the role of cardiac MRI in DCM evaluation?
Cardiac MRI helps in tissue characterization, detects fibrosis, evaluates global function, and can distinguish other cardiomyopathies.
134
When is endomyocardial biopsy indicated in DCM?
Endomyocardial biopsy is reserved for suspected specific etiologies (e.g., myocarditis, metabolic disease) or refractory cases.
135
What is the mainstay of medical management for DCM?
Management includes heart failure therapy to optimize preload, afterload, and contractility, and to prevent complications.
136
What pharmacologic treatments are used in pediatric DCM?
Treatments: diuretics (furosemide), ACE inhibitors (captopril/enalapril), beta-blockers (carvedilol, metoprolol), aldosterone antagonists (spironolactone), and inotropes if needed.
137
When is anticoagulation considered in DCM patients?
Anticoagulation is considered if there is severe LV dysfunction (EF <25%), intracardiac thrombus, or arrhythmias predisposing to thromboembolism.
138
When should mechanical circulatory support be considered in DCM?
Mechanical support (ECMO, VAD) is considered in severe, refractory heart failure or as bridge to transplant.
139
What are common complications associated with DCM?
Complications include progressive heart failure, arrhythmias, thromboembolism, sudden cardiac death, and need for transplantation.
140
What is the prognosis of pediatric DCM?
Prognosis varies: some improve with therapy, but a significant proportion may deteriorate and require transplantation; early intervention improves outcomes.
141
What is Hypertrophic Cardiomyopathy (HCM)?
HCM is a primary myocardial disorder characterized by hypertrophy of the myocardium (usually without dilation) and impaired ventricular relaxation.
142
What is the pathophysiology of HCM?
Myocyte hypertrophy and disarray lead to diastolic dysfunction, myocardial ischemia, arrhythmias, and dynamic LVOT obstruction in some patients.
143
What genetic mutations are commonly associated with HCM?
Mutations in sarcomeric protein genes, including beta-myosin heavy chain (MYH7), myosin-binding protein C (MYBPC3), and troponin T, are common.
144
What are the patterns of hypertrophy seen in HCM?
Hypertrophy patterns include asymmetric septal hypertrophy (most common), concentric hypertrophy, or mid-ventricular hypertrophy.
145
What is asymmetric septal hypertrophy?
Asymmetric septal hypertrophy refers to disproportionate thickening of the interventricular septum relative to the posterior wall (>1.3:1 ratio).
146
What is the role of dynamic left ventricular outflow tract (LVOT) obstruction in HCM?
LVOT obstruction occurs due to systolic anterior motion (SAM) of the mitral valve and narrowed outflow tract, worsening symptoms and risk.
147
What are the clinical features of HCM in children?
Children may present with dyspnea on exertion, chest pain, palpitations, syncope, or be asymptomatic and diagnosed on screening.
148
What symptoms suggest severe HCM?
Severe HCM may present with syncope, exertional chest pain, heart failure symptoms, or sudden cardiac death.
149
What are the common physical examination findings in HCM?
Exam findings: forceful apex beat, systolic ejection murmur (crescendo-decrescendo), and possible S4 gallop.
150
What are the auscultatory findings characteristic of HCM?
Murmur increases with maneuvers that decrease preload (e.g., standing, Valsalva) and decreases with squatting.
151
What ECG findings are typical in HCM?
ECG often shows LV hypertrophy, deep Q waves (especially in inferior and lateral leads), and repolarization abnormalities.
152
What are the chest X-ray findings in HCM?
CXR may show normal heart size or mild cardiomegaly; pulmonary venous congestion if heart failure develops.
153
How does echocardiography diagnose HCM?
Echo shows asymmetric septal hypertrophy, systolic anterior motion (SAM) of mitral valve, and may detect LVOT gradients.
154
What is the role of cardiac MRI in HCM evaluation?
MRI provides detailed tissue characterization, detects areas of fibrosis (late gadolinium enhancement), and clarifies anatomy.
155
When is genetic testing indicated in HCM?
Genetic testing is recommended for affected patients and first-degree relatives to identify pathogenic mutations.
156
What are the first-line medical treatments for HCM?
First-line treatments include beta-blockers (e.g., propranolol) or calcium channel blockers (e.g., verapamil) to reduce symptoms and obstruction.
157
When is septal reduction therapy considered in HCM?
Septal reduction (surgical myectomy or alcohol septal ablation) is considered for patients with severe symptoms and significant LVOT obstruction refractory to medical therapy.
158
What are the indications for ICD placement in pediatric HCM?
ICD placement is indicated in patients with prior cardiac arrest, sustained VT, family history of sudden death, severe LV hypertrophy (>30 mm), or unexplained syncope.
159
What activities should be restricted in patients with HCM?
Competitive sports and strenuous exercise should be avoided to reduce the risk of sudden cardiac death.
160
What is the prognosis of HCM in children?
Prognosis varies; many remain stable with medical therapy, but some are at risk of sudden death or progressive heart failure requiring transplantation.
161
What is Restrictive Cardiomyopathy (RCM)?
RCM is a myocardial disorder characterized by impaired ventricular filling due to stiff, noncompliant ventricular walls, with preserved systolic function early on.
162
What is the pathophysiology of RCM?
The ventricles resist filling during diastole, leading to elevated atrial pressures, atrial enlargement, pulmonary congestion, and low cardiac output.
163
What are the primary causes of RCM in children?
Primary causes include idiopathic RCM, familial forms (sarcomeric gene mutations), and inherited infiltrative disorders (e.g., amyloidosis).
164
What secondary diseases can cause restrictive physiology?
Secondary causes include storage diseases (e.g., Fabry disease), endomyocardial fibrosis, radiation exposure, and iron overload (hemochromatosis).
165
How does RCM differ from constrictive pericarditis?
RCM involves myocardial pathology (stiff myocardium) whereas constrictive pericarditis involves external compression from a thickened pericardium.
166
What are the clinical features of RCM in children?
Children typically present with fatigue, exercise intolerance, dyspnea, orthopnea, syncope, and signs of right or left heart failure.
167
What symptoms suggest advanced RCM?
Advanced RCM symptoms include marked hepatomegaly, ascites, peripheral edema, and pulmonary hypertension signs.
168
What physical examination findings are seen in RCM?
Exam findings: elevated jugular venous pressure, hepatomegaly, peripheral edema, ascites, and sometimes loud S3 gallop.
169
What auscultatory findings are characteristic of RCM?
A soft mid-diastolic murmur due to increased flow across the AV valves may be heard; also possible regurgitation murmurs.
170
What ECG findings are typical in RCM?
ECG shows low voltage QRS complexes, atrial enlargement, and may show arrhythmias (e.g., atrial fibrillation).
171
What chest X-ray findings are typical in RCM?
CXR typically shows marked biatrial enlargement with normal or near-normal ventricular size and pulmonary venous congestion.
172
What echocardiographic features suggest RCM?
Echo shows biatrial enlargement, normal or mildly thickened ventricles, restrictive mitral inflow patterns (short E deceleration time), and preserved EF early.
173
What is the role of cardiac MRI in RCM?
MRI helps distinguish RCM from infiltrative diseases (e.g., amyloidosis) and assess fibrosis or myocardial infiltration.
174
What laboratory tests are helpful in RCM workup?
Helpful labs: BNP/NT-proBNP (elevated), iron studies, genetic testing, serum protein electrophoresis (amyloid), and metabolic screening.
175
When is endomyocardial biopsy considered in RCM?
Biopsy is considered when diagnosis is unclear, especially if distinguishing RCM from infiltrative or inflammatory causes.
176
What are the main complications of RCM?
Complications include progressive congestive heart failure, arrhythmias (especially atrial fibrillation), thromboembolic events, and sudden death.
177
What is the role of medical therapy in RCM?
Medical therapy (diuretics for congestion, anticoagulation if atrial fibrillation) is supportive; no proven disease-modifying therapy.
178
When is heart transplantation indicated in RCM?
Heart transplantation is indicated for end-stage heart failure or intractable symptoms not responsive to medical therapy.
179
How is restrictive physiology managed before transplant?
Management includes symptom control with diuretics, rate/rhythm control if arrhythmias develop, and careful fluid balance monitoring.
180
What is the prognosis of RCM in children?
Prognosis is generally poor without transplant; many children require transplantation within a few years of diagnosis.
181
What is Supraventricular Tachycardia (SVT)?
SVT is a rapid heart rhythm originating above the ventricles, typically with a narrow QRS complex and rates >220 bpm in infants or >180 bpm in children.
182
What are the common mechanisms of SVT in children?
Common mechanisms: accessory pathway-mediated reentry (e.g., WPW), AV nodal reentry, or atrial tachycardia.
183
What are the types of SVT based on mechanism?
Types include AVRT, AVNRT, atrial tachycardia, and junctional ectopic tachycardia.
184
What is the most common cause of SVT in infants?
AVRT mediated by an accessory pathway (e.g., WPW) is the most common cause of SVT in infants.
185
What is atrioventricular reentrant tachycardia (AVRT)?
AVRT involves an accessory pathway allowing reentrant circuit between atria and ventricles, often orthodromic (anterograde AV node, retrograde accessory).
186
What is atrioventricular nodal reentrant tachycardia (AVNRT)?
AVNRT involves a reentrant circuit within the AV node using slow and fast pathways causing sudden onset and termination of tachycardia.
187
What are the clinical features of SVT in infants?
Infants may present with poor feeding, irritability, diaphoresis, tachypnea, pallor, and signs of heart failure if prolonged.
188
What are the clinical features of SVT in older children?
Older children present with palpitations, chest discomfort, dizziness, syncope, or exercise intolerance.
189
What physical examination findings suggest SVT?
Findings: rapid regular heart rate, cool extremities if prolonged, hepatomegaly in infants, and signs of low cardiac output if prolonged.
190
What ECG findings are typical of SVT?
ECG shows narrow complex tachycardia, absent or retrograde P waves, regular rhythm, and heart rate typically >180–220 bpm.
191
What are the characteristics of WPW syndrome on ECG?
WPW shows short PR interval, delta wave (slurred upstroke of QRS), and wide QRS when not in tachycardia.
192
What is the first step in acute management of SVT?
First step is attempting vagal maneuvers if the patient is stable.
193
What vagal maneuvers can be used to terminate SVT?
Vagal maneuvers include ice bag to the face (infants), Valsalva maneuver (older children), or carotid sinus massage (with caution).
194
What is the drug of choice for acute pharmacologic termination of SVT?
Adenosine is the drug of choice; it transiently blocks AV nodal conduction to terminate AVRT and AVNRT.
195
When is synchronized cardioversion indicated in SVT?
Synchronized cardioversion is indicated if the patient is hemodynamically unstable or if SVT persists after vagal maneuvers and adenosine.
196
What are chronic management options for recurrent SVT?
Options include observation (if infrequent episodes), chronic medications, or catheter ablation depending on severity and frequency.
197
What medications are used for chronic SVT prevention?
Chronic medications include beta-blockers (e.g., propranolol), digoxin (avoid in WPW with atrial fibrillation), and antiarrhythmics (e.g., flecainide).
198
What is the role of radiofrequency ablation in SVT?
Radiofrequency ablation is highly effective (>95% cure rates) and is preferred in older children or refractory/recurrent cases.
199
What are the indications for EP study and ablation in children with SVT?
Indications for ablation: symptomatic SVT despite medications, WPW with high-risk features, patient preference, or heart failure symptoms.
200
What is the prognosis for children with SVT?
Prognosis is excellent; many infants outgrow SVT, and older children can be effectively managed medically or with ablation.
201
What is an atrioventricular (AV) block?
AV block is an impairment of conduction between the atria and ventricles, leading to delayed or absent transmission of atrial impulses to the ventricles.
202
What are the degrees of AV block?
Degrees:
- First-degree: prolonged PR interval
- Second-degree: intermittent non-conduction
- Third-degree: complete dissociation of atrial and ventricular activity.
203
What are the causes of congenital AV block?
Causes include maternal autoimmune disease (anti-Ro/SSA, anti-La/SSB antibodies), congenital heart defects (e.g., L-transposition), and idiopathic cases.
204
What are the causes of acquired AV block in children?
Acquired causes include post-surgical injury (especially after VSD or AVSD repair), myocarditis, cardiomyopathies, Lyme disease, and medications (e.g., digoxin, beta-blockers).
205
What are the types of first-degree AV block?
First-degree AV block involves delayed conduction through the AV node but all atrial impulses are conducted to ventricles.
206
What are the ECG findings in first-degree AV block?
ECG shows prolonged PR interval (>200 ms in adolescents; longer for younger children) without dropped beats.
207
What are the types of second-degree AV block?
Second-degree AV block includes:
- Mobitz type I (Wenckebach): progressive PR prolongation leading to a dropped beat
- Mobitz type II: sudden dropped beat without PR prolongation.
208
What are the ECG features of Mobitz type I (Wenckebach) AV block?
Mobitz I shows progressively lengthening PR intervals followed by a non-conducted P wave (dropped QRS), then cycle repeats.
209
What are the ECG features of Mobitz type II AV block?
Mobitz II shows constant PR intervals with sudden non-conducted P waves (QRS dropped unpredictably); more serious.
210
What are the characteristics of third-degree (complete) AV block?
Third-degree AV block shows complete atrioventricular dissociation with independent atrial and ventricular rhythms.
211
What symptoms may occur in children with AV block?
Symptoms include fatigue, exercise intolerance, syncope, palpitations, dizziness, or signs of heart failure in severe cases.
212
How does congenital complete AV block typically present?
Congenital complete AV block often presents with bradycardia detected in utero or at birth; some may remain asymptomatic for years.
213
What are the risk factors for congenital complete AV block?
Risk factors: maternal autoimmune disease (SLE, Sjögren’s syndrome), structural heart defects (especially L-TGA), or isolated cases.
214
What role does maternal autoimmunity play in congenital AV block?
Maternal anti-Ro/SSA and anti-La/SSB antibodies cross the placenta, damaging the fetal conduction system and causing fibrosis leading to block.
215
How is AV block diagnosed in children?
Diagnosis is based on ECG findings; ambulatory Holter monitoring and event monitors may help if symptoms are intermittent.
216
What is the acute management of symptomatic bradycardia due to AV block?
Acute management includes supportive care, atropine for symptomatic bradycardia, and temporary pacing if unstable.
217
When is pacemaker implantation indicated in pediatric AV block?
Indications for pacemaker: symptomatic bradycardia, ventricular dysfunction, wide QRS escape rhythms, or very slow ventricular rates (<55 bpm in infants; <40 bpm in older children).
218
What are the long-term considerations for children with pacemakers?
Long-term issues include pacing site complications, device replacement, lead fractures, and potential for pacing-induced cardiomyopathy.
219
What is the prognosis for children with AV block?
Prognosis is good with pacemaker therapy; congenital isolated complete AV block without heart failure generally has favorable outcomes.
220
How does the management of AV block differ between congenital and acquired types?
Congenital AV block often requires early pacemaker placement if symptomatic; acquired AV block may resolve (e.g., post-myocarditis) or also require pacing if persistent.
221
What is Long QT Syndrome (LQTS)?
LQTS is a disorder of myocardial repolarization characterized by a prolonged QT interval on ECG and increased risk of ventricular arrhythmias and sudden cardiac death.
222
What is the pathophysiology of LQTS?
Delayed repolarization increases the risk of early afterdepolarizations, leading to torsades de pointes and polymorphic ventricular tachycardia.
223
What is a normal QTc interval in children?
Normal QTc:
- Infants: <490 ms
- Children: <450 ms
- Adolescents/adults: <440 ms.
224
What are the inherited types of LQTS?
Inherited forms include LQT1, LQT2, LQT3, and others (LQT4–13), based on specific gene mutations and clinical features.
225
What genes are commonly mutated in congenital LQTS?
Common genes: KCNQ1 (LQT1), KCNH2 (LQT2), and SCN5A (LQT3).
226
What are triggers for arrhythmias in different types of LQTS?
Triggers:
- LQT1: exercise (especially swimming)
- LQT2: emotional stress or auditory stimuli
- LQT3: rest or sleep.
227
What is Jervell and Lange-Nielsen syndrome?
Jervell and Lange-Nielsen syndrome is an autosomal recessive form of LQTS associated with profound congenital sensorineural deafness.
228
What is Romano-Ward syndrome?
Romano-Ward syndrome is an autosomal dominant form of congenital LQTS without associated deafness.
229
What acquired conditions can prolong the QT interval?
Acquired causes: hypokalemia, hypocalcemia, hypomagnesemia, bradycardia, myocardial ischemia, CNS events, and drugs.
230
What medications can cause acquired LQTS?
Drugs: antiarrhythmics (e.g., sotalol, quinidine), antibiotics (e.g., erythromycin, azithromycin), antifungals, antipsychotics, antidepressants.
231
What symptoms are associated with LQTS?
Symptoms include palpitations, syncope, seizures (due to cerebral hypoperfusion), and sudden cardiac death.
232
What arrhythmia is most commonly associated with LQTS?
The primary arrhythmia associated with LQTS is torsades de pointes (a form of polymorphic ventricular tachycardia).
233
What is torsades de pointes?
Torsades de pointes is a polymorphic VT characterized by a twisting of the QRS axis around the baseline, often self-terminating but may cause sudden death.
234
How is the diagnosis of LQTS made?
Diagnosis is based on QTc prolongation, clinical history, family history, and genetic testing if available.
235
What is the Schwartz score?
The Schwartz score incorporates ECG findings, clinical symptoms, and family history to estimate the probability of LQTS.
236
What is the first-line treatment for congenital LQTS?
Beta-blockers (propranolol, nadolol) are the first-line therapy; they reduce adrenergic stimulation and lower arrhythmia risk.
237
When is an ICD indicated in LQTS?
ICD is indicated for survivors of cardiac arrest, syncope on beta-blocker therapy, or high-risk genotypes (e.g., LQT3).
238
What lifestyle modifications are recommended in LQTS?
Patients should avoid competitive sports (except under special protocols), QT-prolonging medications, and maintain electrolyte balance.
239
What is the role of left cardiac sympathetic denervation in LQTS?
Left cardiac sympathetic denervation surgery may be considered for refractory cases or when ICD is not feasible.
240
What is the prognosis for children with properly treated LQTS?
With proper treatment, the prognosis is excellent, with markedly reduced risk of sudden death.
241
What is Wolff-Parkinson-White (WPW) Syndrome?
WPW is a pre-excitation syndrome characterized by the presence of an accessory pathway allowing early ventricular activation and predisposition to tachyarrhythmias.
242
What is the pathophysiology of WPW?
An abnormal bundle (accessory pathway) connects the atria and ventricles, bypassing the AV node and allowing rapid conduction.
243
What is the name of the accessory pathway in WPW?
The accessory pathway is called the bundle of Kent.
244
How does WPW syndrome differ from concealed accessory pathways?
In WPW syndrome, the accessory pathway conducts antegradely (atria to ventricles); in concealed pathways, conduction is only retrograde.
245
What are the ECG features of WPW pattern?
ECG features: short PR interval (<120 ms), delta wave (slurred QRS upstroke), and widened QRS complex (>120 ms).
246
What is a delta wave?
A delta wave is the initial slurring of the QRS upstroke caused by early activation of the ventricle through the accessory pathway.
247
What symptoms are associated with WPW syndrome?
Symptoms include palpitations, dizziness, syncope, chest pain, and rarely sudden cardiac death.
248
What arrhythmias are commonly associated with WPW?
Common arrhythmias: AVRT (orthodromic or antidromic), atrial fibrillation with rapid conduction via the accessory pathway, and rarely ventricular fibrillation.
249
What are the risks associated with WPW syndrome?
Risks include rapid atrial fibrillation leading to ventricular fibrillation and sudden cardiac death, especially in high-risk pathways.
250
What is the risk of sudden cardiac death in WPW?
The risk of sudden cardiac death in WPW is about 0.1–0.2% per year; higher if atrial fibrillation conducts rapidly to ventricles.
251
What is orthodromic AV reentrant tachycardia (AVRT) in WPW?
Orthodromic AVRT: antegrade conduction through AV node and retrograde conduction via accessory pathway; narrow QRS tachycardia.
252
What is antidromic AVRT in WPW?
Antidromic AVRT: antegrade conduction via accessory pathway and retrograde conduction via AV node; wide QRS tachycardia.
253
How is WPW syndrome diagnosed?
Diagnosis is made by ECG findings or by EP study if concealed pathways or risk stratification is needed.
254
What is the acute management of tachyarrhythmias in WPW?
Acute management: vagal maneuvers first; if unstable, synchronized cardioversion; avoid AV nodal blockers in pre-excited atrial fibrillation.
255
Why is AV nodal blocking agent contraindicated in atrial fibrillation with WPW?
AV nodal blockers (e.g., adenosine, beta-blockers, calcium channel blockers) can block the AV node and enhance conduction via the accessory pathway, risking VF.
256
What medications are preferred in atrial fibrillation with WPW?
Preferred medications include procainamide or ibutilide to slow conduction via the accessory pathway.
257
What is the definitive treatment for WPW syndrome?
Definitive treatment is catheter ablation of the accessory pathway, achieving cure in >95% of cases.
258
When is radiofrequency ablation indicated in WPW?
Ablation is indicated for symptomatic patients, high-risk EP features, or professions at risk (e.g., pilots, athletes).
259
What are high-risk features on EP study in WPW?
High-risk features: short accessory pathway refractory period (<250 ms), multiple pathways, inducible rapid atrial fibrillation, or syncope with pre-excitation.
260
What is the prognosis for WPW after successful ablation?
Prognosis is excellent after successful ablation, with low recurrence rates and resolution of arrhythmia risk.
261
What is infective endocarditis (IE)?
IE is an infection of the endocardial surface of the heart, typically involving heart valves, caused by bacteria, fungi, or other microorganisms.
262
What are the common risk factors for IE in children?
Risk factors include congenital heart disease (especially cyanotic defects), prosthetic valves, previous IE, indwelling central venous catheters, and immunosuppression.
263
Which congenital heart diseases are associated with higher risk of IE?
High-risk CHD lesions: unrepaired cyanotic heart disease, prosthetic valves, prior history of IE, and post-surgical residual defects.
264
What are the most common causative organisms of pediatric IE?
Common organisms: Staphylococcus aureus, Viridans group streptococci, coagulase-negative staphylococci, Enterococcus, and HACEK organisms.
265
What is the pathophysiology of IE?
Pathogenesis involves bacteremia leading to colonization of damaged endocardial surfaces, vegetation formation, and potential embolization.
266
What are the classic clinical features of IE in children?
Clinical features: persistent fever, malaise, fatigue, weight loss, arthralgia, and signs of heart failure if valve dysfunction occurs.
267
What are the peripheral signs of IE?
Peripheral signs: petechiae, splinter hemorrhages, Janeway lesions, Osler nodes, and Roth spots (retinal hemorrhages).
268
What are the typical findings on physical examination in IE?
Exam may reveal a new or changing murmur, signs of embolic phenomena, splenomegaly, or signs of heart failure.
269
What is the significance of a new murmur in IE?
A new or changing murmur often suggests valvular involvement and is a major diagnostic clue in IE.
270
What are the diagnostic criteria for IE?
Diagnosis is based on clinical suspicion, blood cultures, echocardiographic evidence, and meeting Duke criteria.
271
What blood investigations are important in suspected IE?
Important labs: multiple blood cultures, inflammatory markers (ESR, CRP), complete blood count (anemia, leukocytosis), renal function tests, and urinalysis.
272
How many blood cultures should be obtained for IE diagnosis?
At least three sets of blood cultures should be drawn from separate sites before starting antibiotics.
273
What is the role of echocardiography in IE?
Echo (especially transesophageal) identifies vegetations, valve destruction, abscesses, and prosthetic valve involvement.
274
What are the Duke criteria for diagnosing IE?
Duke criteria combine clinical, microbiologic, and echocardiographic findings into major and minor criteria to establish diagnosis.
275
What are the major Duke criteria?
Major criteria: positive blood cultures for typical organisms, evidence of endocardial involvement on echocardiography.
276
What are the minor Duke criteria?
Minor criteria: predisposing heart condition or IV drug use, fever ≥38°C, vascular phenomena, immunologic phenomena, and positive blood cultures not meeting major criteria.
277
What are the common complications of IE?
Complications: heart failure, embolic events (stroke, infarction), valve destruction, abscess formation, and death if untreated.
278
What is the first-line antibiotic therapy for native valve IE?
First-line empiric therapy: vancomycin plus gentamicin until organism identification and sensitivities are available.
279
When is surgical intervention indicated in IE?
Surgery is indicated for heart failure due to valvular dysfunction, uncontrolled infection, large vegetations (>10 mm) with embolic risk, or abscess formation.
280
What is the prognosis for pediatric IE with appropriate treatment?
With timely and appropriate antibiotic therapy, prognosis is good (>80–90% survival), but relapse or complications require close follow-up.
281
What is Acute Rheumatic Fever (ARF)?
ARF is a multisystem inflammatory disease following untreated or inadequately treated group A streptococcal pharyngitis, affecting the heart, joints, skin, and brain.
282
What is the pathophysiology of ARF?
ARF is caused by molecular mimicry where antibodies directed against streptococcal antigens cross-react with host tissues (e.g., heart, joints, CNS).
283
Which organism is responsible for triggering ARF?
Group A beta-hemolytic Streptococcus (Streptococcus pyogenes).
284
What are the major Jones criteria for diagnosing ARF?
Major Jones criteria:
- Carditis
- Arthritis (polyarthritis)
- Chorea (Sydenham chorea)
- Erythema marginatum
- Subcutaneous nodules.
285
What are the minor Jones criteria for diagnosing ARF?
Minor Jones criteria:
- Fever
- Arthralgia
- Elevated acute-phase reactants (ESR, CRP)
- Prolonged PR interval on ECG.
286
What constitutes evidence of preceding streptococcal infection?
Evidence includes:
- Positive throat culture for group A streptococcus
- Positive rapid antigen detection test
- Elevated or rising antistreptolysin O (ASO) titer or anti-DNase B antibodies.
287
What are the classic clinical features of ARF?
Clinical features: fever, migratory polyarthritis, carditis (pancarditis), Sydenham chorea, erythema marginatum, and subcutaneous nodules.
288
What is the most common manifestation of ARF?
Arthritis is the most common manifestation, occurring in about 75% of cases.
289
Describe the arthritis seen in ARF.
It is a migratory, inflammatory arthritis affecting large joints (knees, ankles, elbows, wrists), resolving without permanent damage.
290
What is Sydenham chorea?
Sydenham chorea is a neurological manifestation with purposeless, involuntary movements, emotional lability, and muscle weakness.
291
What are the features of rheumatic carditis?
Carditis can involve all layers of the heart (pancarditis) leading to murmurs (e.g., mitral or aortic regurgitation), cardiomegaly, and heart failure signs.
292
What is erythema marginatum?
Erythema marginatum is a non-pruritic, pink rash with a serpiginous edge, typically on the trunk and proximal extremities.
293
What are subcutaneous nodules in ARF?
Subcutaneous nodules are firm, painless nodules over bony prominences, associated with severe carditis.
294
How is ARF diagnosed based on Jones criteria?
Diagnosis: 2 major criteria, or 1 major + 2 minor criteria, plus evidence of preceding streptococcal infection.
295
What investigations are helpful in ARF evaluation?
Helpful tests: throat culture, ASO titers, anti-DNase B, ESR, CRP, ECG (PR prolongation), echocardiography (valvulitis).
296
What is the role of echocardiography in ARF?
Echo detects valvular regurgitation (especially mitral and aortic valves) even when auscultatory findings are absent (subclinical carditis).
297
What is the initial treatment of ARF?
Initial treatment includes eradication of streptococcal infection, anti-inflammatory therapy (aspirin or steroids), and supportive care.
298
What antibiotics are used to eradicate streptococcal infection in ARF?
Antibiotic of choice: intramuscular benzathine penicillin G; oral penicillin V or amoxicillin alternatives in some cases.
299
What is the role of secondary prophylaxis in ARF?
Secondary prophylaxis with monthly benzathine penicillin G prevents recurrence and progression to rheumatic heart disease.
300
What is the prognosis of ARF, especially regarding rheumatic heart disease?
Most symptoms resolve with treatment; however, rheumatic carditis can lead to chronic rheumatic heart disease requiring long-term follow-up.
301
What is Kawasaki Disease?
Kawasaki Disease is an acute, self-limited vasculitis predominantly affecting medium-sized arteries, especially coronary arteries, in young children.
302
What is the pathophysiology of Kawasaki Disease?
The pathogenesis involves immune-mediated inflammation of blood vessels following an infectious or environmental trigger in genetically susceptible individuals.
303
What age group is most commonly affected by Kawasaki Disease?
Most commonly affects children between 6 months and 5 years of age, with a peak incidence at 1–2 years.
304
What are the diagnostic criteria for classic Kawasaki Disease?
Fever for ≥5 days plus at least 4 of the 5 principal clinical features, or fewer features with coronary artery abnormalities on imaging.
305
What are the principal clinical features of Kawasaki Disease?
Principal features:
- Bilateral nonexudative conjunctivitis
- Oropharyngeal changes (e.g., strawberry tongue)
- Polymorphous rash
- Extremity changes (e.g., desquamation)
- Cervical lymphadenopathy (≥1.5 cm).
306
What is the definition of incomplete Kawasaki Disease?
Incomplete Kawasaki Disease refers to patients with prolonged fever and fewer than 4 principal features but with laboratory or echocardiographic evidence supporting the diagnosis.
307
What are the early (acute phase) clinical features of Kawasaki Disease?
Acute phase (first 1–2 weeks) features: high spiking fever, irritability, conjunctivitis, rash, mucosal changes, extremity swelling/erythema, and lymphadenopathy.
308
What laboratory findings are typically seen in Kawasaki Disease?
Labs: elevated ESR, CRP, leukocytosis (neutrophilia), thrombocytosis (in subacute phase), anemia, elevated liver enzymes, sterile pyuria.
309
What cardiovascular complications are associated with Kawasaki Disease?
Cardiovascular complications include coronary artery aneurysms, myocarditis, pericarditis, valvular regurgitation, and arrhythmias.
310
What is the most serious complication of Kawasaki Disease?
Coronary artery aneurysm formation is the most serious complication of Kawasaki Disease.
311
How is echocardiography used in Kawasaki Disease evaluation?
Echocardiography assesses coronary artery dimensions, ventricular function, valvular regurgitation, and pericardial effusion.
312
When should echocardiography be performed in Kawasaki Disease?
Echo should be performed at diagnosis, at 1–2 weeks, and at 4–6 weeks after onset of illness.
313
What is the initial treatment of Kawasaki Disease?
Initial treatment includes high-dose IVIG and aspirin therapy as soon as possible, ideally within 10 days of fever onset.
314
What is the role of intravenous immunoglobulin (IVIG) in Kawasaki Disease?
IVIG (2 g/kg single dose) reduces systemic inflammation and markedly decreases the risk of coronary artery aneurysms.
315
What is the role of aspirin in Kawasaki Disease management?
Aspirin is initially given in high doses for anti-inflammatory effect during the acute phase, then continued at low doses for antiplatelet effect.
316
When is corticosteroid therapy considered in Kawasaki Disease?
Corticosteroids are considered in high-risk patients or those predicted to have IVIG resistance (e.g., very high CRP, hypoalbuminemia).
317
What is the treatment approach for IVIG-resistant Kawasaki Disease?
For IVIG-resistant Kawasaki Disease, a second dose of IVIG, corticosteroids, or biologics (e.g., infliximab) may be used.
318
What is the prognosis of Kawasaki Disease with timely treatment?
With timely IVIG treatment, the risk of coronary aneurysms is reduced from ~25% to <5%.
319
What long-term follow-up is needed after Kawasaki Disease?
Children with coronary involvement require long-term cardiology follow-up; those without involvement need periodic follow-up for several years.
320
What are the risk factors for coronary artery aneurysm development in Kawasaki Disease?
Risk factors: delayed IVIG treatment, prolonged fever, male sex, age <12 months or >8 years, Asian ancestry, and elevated inflammatory markers.
321
What is the definition of systemic hypertension in children?
Systemic hypertension is defined as average systolic and/or diastolic BP ≥95th percentile for age, sex, and height on three separate occasions.
322
How is blood pressure classified in children?
BP is classified based on percentiles:
- Normal: <90th percentile
- Elevated BP: 90–95th percentile
- Stage 1 HTN: 95th–95th +12 mmHg
- Stage 2 HTN: >95th percentile +12 mmHg or >140/90 (whichever is lower).
323
What are the categories of hypertension in pediatrics according to the 2017 AAP guidelines?
Categories:
- Elevated BP
- Stage 1 Hypertension
- Stage 2 Hypertension.
324
What are the primary causes of hypertension in children?
Primary (essential) hypertension is often seen in adolescents and is related to obesity, family history, and sedentary lifestyle.
325
What are the secondary causes of hypertension in children?
Secondary hypertension is due to underlying pathology such as renal disease, endocrine disorders, coarctation of the aorta, or medication use.
326
What are the most common secondary causes in different pediatric age groups?
Infants: renal artery stenosis, congenital renal anomalies.
Children: renal parenchymal disease.
Adolescents: primary hypertension predominates.
327
What are the risk factors for primary hypertension in adolescents?
Risk factors: obesity, family history of hypertension, high salt intake, sedentary lifestyle, and sleep-disordered breathing.
328
What are the symptoms of hypertension in children?
Hypertension is often asymptomatic but may present with headache, dizziness, visual disturbances, or epistaxis.
329
What are the signs of hypertensive emergencies in children?
Signs of hypertensive emergencies include encephalopathy (seizures, altered consciousness), heart failure, and acute renal failure.
330
What physical examination findings are important in pediatric hypertension evaluation?
Important findings: BP in all four limbs, abdominal bruits, signs of coarctation (differential BP/weak femoral pulses), fundoscopic exam (hypertensive retinopathy).
331
What basic investigations should be performed in newly diagnosed pediatric hypertension?
Initial workup: urinalysis, BUN/creatinine, electrolytes, fasting glucose, lipid profile, renal ultrasound, and echocardiography to assess for LV hypertrophy.
332
What additional investigations are needed to identify secondary causes of hypertension?
Further investigations: plasma renin, aldosterone, cortisol, thyroid function tests, catecholamines, imaging for renal arteries or coarctation.
333
What is ambulatory blood pressure monitoring (ABPM) and its role?
ABPM measures BP over 24 hours, detects white coat hypertension, masked hypertension, and evaluates BP patterns.
334
When is hypertension considered an emergency in children?
Emergency: severe BP elevation with end-organ dysfunction (encephalopathy, heart failure, acute kidney injury, seizures).
335
What are the goals of therapy in pediatric hypertension?
Goals: reduce BP gradually to avoid hypoperfusion, protect target organs, and treat underlying causes if present.
336
What are non-pharmacological treatments for pediatric hypertension?
Non-pharmacologic therapy: weight loss, healthy diet (DASH diet), physical activity, salt restriction, and avoiding tobacco.
337
When is pharmacologic therapy indicated in children with hypertension?
Indications: symptomatic HTN, secondary HTN, target organ damage (LVH), stage 2 HTN, or failure of lifestyle measures.
338
What are the first-line antihypertensive medications in children?
First-line agents: ACE inhibitors (enalapril), ARBs (losartan), calcium channel blockers (amlodipine), thiazide diuretics.
339
What are the common causes of hypertensive crisis in pediatrics?
Hypertensive crises can result from renal disease, neuroendocrine tumors (pheochromocytoma), severe glomerulonephritis, or nonadherence to therapy.
340
What is the prognosis for children with treated hypertension?
Prognosis is good with early identification and management; untreated HTN increases risk of cardiovascular disease and renal damage in adulthood.
341
What is pulmonary hypertension (PH)?
PH is elevated pressure in the pulmonary arteries leading to right ventricular strain and failure if untreated.
342
How is pulmonary hypertension defined in pediatrics?
Defined as mean pulmonary artery pressure (mPAP) ≥20 mmHg at rest by right heart catheterization (updated 2018 definition).
343
What are the categories of pulmonary hypertension according to the WHO classification?
WHO groups:
- Group 1: Pulmonary arterial hypertension (PAH)
- Group 2: PH due to left heart disease
- Group 3: PH due to lung disease/hypoxia
- Group 4: Chronic thromboembolic PH
- Group 5: PH with unclear mechanisms.
344
What are common causes of pulmonary arterial hypertension (PAH) in children?
Idiopathic PAH, heritable PAH, congenital heart disease-associated PAH (e.g., unrepaired left-to-right shunts).
345
What congenital heart diseases are associated with PH?
VSD, ASD, PDA, AV canal defect, truncus arteriosus (especially if left-to-right shunts are large and untreated).
346
What are causes of PH due to left heart disease in children?
Left-sided valvular diseases (mitral stenosis, mitral regurgitation), cardiomyopathies, and pulmonary vein stenosis.
347
What are lung diseases that can cause pulmonary hypertension?
Bronchopulmonary dysplasia, interstitial lung diseases, cystic fibrosis, and congenital diaphragmatic hernia.
348
What are the clinical features of pulmonary hypertension in children?
Symptoms include exertional dyspnea, fatigue, syncope, chest pain, and signs of right heart failure (e.g., hepatomegaly, edema).
349
What physical exam findings suggest PH?
Findings: loud P2 component of S2, right ventricular heave, jugular venous distension, hepatomegaly, peripheral edema.
350
What is the significance of a loud second heart sound in PH?
A loud and palpable second heart sound (P2) suggests elevated pulmonary artery pressures and right ventricular strain.
351
What are the ECG findings in pulmonary hypertension?
ECG may show right atrial enlargement, right ventricular hypertrophy, and right axis deviation.
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What chest X-ray findings may suggest pulmonary hypertension?
CXR may show right atrial and ventricular enlargement, prominent pulmonary arteries, and pruning of peripheral vasculature.
353
How is echocardiography used in diagnosing PH?
Echo estimates pulmonary pressures, evaluates right ventricular size and function, assesses for congenital heart disease.
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What is the role of cardiac catheterization in PH evaluation?
Cardiac catheterization measures pulmonary pressures, pulmonary vascular resistance, and assesses vasoreactivity to guide therapy.
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What laboratory and imaging tests are used in evaluating PH etiology?
Tests include chest CT, V/Q scan (to rule out thromboembolism), ANA (connective tissue diseases), HIV, liver function tests, and sleep studies.
356
What are the initial therapies for pulmonary hypertension?
Initial therapies include treating underlying cause, oxygen supplementation, diuretics if heart failure is present, and anticoagulation in selected cases.
357
What medications are used to treat pediatric pulmonary arterial hypertension?
Medications: endothelin receptor antagonists (bosentan), phosphodiesterase-5 inhibitors (sildenafil), prostacyclin analogs (epoprostenol, iloprost).
358
When is oxygen therapy indicated in PH?
Oxygen is indicated if hypoxemia is present, especially in PH associated with lung disease or sleep-disordered breathing.
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What are advanced therapies for refractory PH?
Advanced therapies include continuous intravenous prostacyclin infusion, atrial septostomy, or lung transplantation.
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What is the prognosis for pediatric pulmonary hypertension?
Prognosis depends on cause and response to therapy; with newer therapies, survival and quality of life have improved significantly.
