MURMURS
Normal Heart Sounds
S1 may split.
S2 normally splits with respiration.
S3 can represent normal, rapid ventricular refilling.
P2 should be soft after infancy.
The difference between grade I and II murmur: A grade I can be heard only in a quiet room with a quiet child.
EPIDEMIOLOGY
Up to 90% of children have a murmur at some point in their lives.
Two to seven percent of murmurs in children represent pathology.
DESCRIPTION AND GRADING
Murmurs are graded for intensity on a six-point system:
Grade I: Very soft murmur detected only after very careful auscultation.
Grade II: Soft murmur that is readily heard but faint (equal to S1/S2).
Grade III: Moderately intense murmur not associated with a palpable precordial thrill (louder than S1 or S2).
Grade IV: Loud murmur; a palpable precordial thrill is not present or is intermittent.
Grade V: Loud murmur associated with a palpable precordial thrill; the murmur is not audible when the stethoscope is lifted from the chest.
Grade VI: Loud murmur associated with a palpable precordial thrill. It can be heard even when the stethoscope is lifted slightly from the chest.
Murmur grading is usually written as “Grade [#]/6.”
SITES OF AUSCULTATION
See Figure 13-1 to correlate the following points:
1. This site corresponds to the location of the carotid arteries. Common murmurs heard here: carotid bruit, aortic stenosis (AS). AS is usually louder at the right upper sternal border and often has an associated ejection click.
2. Aortic valve. Right upper sternal border. Common murmurs: aortic valve stenosis (supravalvular, valvular, and subvalvular). Valvular stenosis will often have an ejection click, whereas the others will not.
FIGURE 13-1. Sites of auscultation.
Murmurs of ASD and TAPVR are secondary pulmonary flow murmurs.
3. Pulmonic valve. Left upper sternal border. Common murmurs: pulmonary valve stenosis, atrial septal defect (ASD), pulmonary flow murmur, pulmonary artery stenosis, AS, coarctation of the aorta, patent ductus arteriosus (PDA), total anomalous pulmonary venous return (TAPVR).
4. Tricuspid valve. Left lower sternal border. Common murmurs: ventricular septal defect (VSD), Still’s murmur, hypertrophic obstructive cardiomyopathy (HOCM), tricuspid regurgitation, endocardial cushion defect.
5. Mitral valve. Apex. Common murmurs: mitral regurgitation, mitral valve prolapse, Still’s murmur, aortic stenosis, HOCM.
6. This site correlates with areas of venous confluence. Common murmurs: venous hum or subclavian bruit.
Accentuation Maneuvers
Various positions and activities can diminish and intensify a murmur (see Table 13-1). The following section also reiterates the positions that aid in diagnosing innocent murmurs.
TABLE 13-1. Accentuation Maneuvers for Pathologic Murmurs
TABLE 13-2. Innocent Murmurs
Reminders for a systematic cardiac exam:
1. Assess the child’s appearance, color, etc.
2. Palpate the precordium.
3. Listen in a quiet room, during systole and diastole.
4. Listen first for heart sounds, then repeat your “sweep” of the chest for murmurs.
5. Don’t forget to listen to the back and in the axillae.
6. Move the patient in different positions.
7. Feel the pulses and assess capillary refill.
8. Palpate the liver.
INNOCENT MURMURS
Pulmonary flow murmurs, physiologic pulmonary branch stenosis, and Still’s murmurs can all be heard best when the patient is supine versus upright.
A Still’s murmur may disappear with the Valsalva maneuver.
Pulmonary flow murmurs are augmented by full exhalation, diminished by inhalation.
Venous hum can be extinguished or accentuated with head and neck movement. It disappears in the supine position, and can also be eliminated with digital compression of the jugular vein.
PATHOLOGIC MURMURS
See Table 13-1.
Innocent Murmurs
Common to all innocent murmurs are:
Absence of structural heart defects.
Normal heart sounds (S1, S2).
Normal peripheral pulses.
Normal chest radiographs and electrocardiogram (ECG).
Asymptomatic.
Usually systolic and graded less than III.
No association with cardiovascular disease.
Accentuate in high-output states (fever and anemia).
See Table 13-2.
INTERPRETATION OF PEDIATRIC ECGs
Any murmur > grade III is likely pathologic.
Always approach an ECG systematically:
1. Measure atrial and ventricular rates.
2. Define the rhythm (sinus, or other).
3. Measure the P-R interval, QRS duration, and Q-T interval.
4. Measure the axes of the P waves, QRS complexes, and T waves.
5. Look for abnormalities of wave patterns and voltages.
Pediatric considerations:
The interpretation is age dependent.
Heart rate varies with age—higher in infants and children.
The QRS duration is shorter in children.
PR interval is shorter.
QTc is longer in infants than in older children (QT interval varies with heart rate).
Right axis deviation alone not enough as a criterion for right venticular hypertrophy (RVH).
Cardiology consultation is indicated with any “noninnocent” murmur.
Expiration Rate
Age-dependent—see Table 13-3.
TABLE 13-3. Heart Rate by Age
ECG Paper
Speed = 25 mm/s.
Small box = 0.04 sec = 1 mm.
Large box = 0.20 sec = 5 mm.
Atrial Rate
Look for P wave count that exceeds QRS complex count.
If P wave number is greater than QRS complex number, an atrial dysrhythmia may be present.
Premature atrial contractions (PACs) are common in infancy.
Ventricular Rate
Count number of small boxes between 2 R waves, then divide into 1500.
Count R-R cycles in six large divisions, then multiply by 50 (use with irregular or fast rate).
Bradycardia
Found in sleep, sedation, vagal stimulation (stooling, cough, or gag), hypothyroid, hyperkalemia, hypothermia, hypoxia, athletic heart, second- or third-degree atrioventricular (AV) block, junctional rhythm, ↑ intracranial pressure, medicine (ie, digitalis, β blockers). Hypoxemia is the most common cause of bradycardia.
Tachycardia
Found in fever, anxiety, hypovolemia, sepsis, congestive heart failure (CHF), hyperthyroidism, supraventricular tachycardia (SVT), ventricular tachycardia, atrial flutter and fibrillation, medicine (ie, theophylline, stimulants).
Sinus Arrhythmia
Normal variation in heart rate, due to inspiration and expiration (commonly seen in childhood).
Rhythm
Check for sinus rhythm:
Verify a P wave before every QRS complex.
Verify a QRS complex after every P wave.
All P waves should look the same.
Normal P wave axis (0° to +90°).
Upright P waves in leads I and aVF.
Normal P wave:
< 0.10 sec in children.
< 0.08 sec in infant.
P-R INTERVAL
Beginning of P to beginning of QRS.
Prolonged P-R (first-degree AV block): Found in myocarditis, digitalis, hyperkalemia, ischemia, ↑ vagal tone, hyperthyroidism.
Short P-R: Found in ectopic atrial pacemaker, preexcitation syndromes (Wolff-Parkinson-White syndrome [WPW], Lown-Ganong-Levine syndrome), and glycogen storage disease. It may show patient is at risk for SVT.
QRS DURATION
Prolonged: Found in right bundle branch block (RBBB), left bundle branch block (LBBB), WPW, premature ventricular contractions (PVCs), mechanical pacemaker rhythms.
QT AND QTC
QTc—corrected QT.
Normal: < 0.45 (< 6 months), < 0.44 (> 6 months).
Beginning of Q to end of T.
QTc = QT interval (sec) divided by the square root of the R-R interval (sec).
Long QT predisposes to ventricular tachycardia and is associated with sudden death.
QT—Congenital Syndromes
WPW
Ischemic heart disease
Drugs
Torsades
Hypokalemia,
Hypomagnesemia,
Hypocalcemia
Abnormal Rhythms
PREMATURE ATRIAL CONTRACTION (PAC)
Preceded by a P wave, followed by a normal QRS.
The length of two cycles (R-R) including a PAC is usually shorter than the length of two normal cycles.
No hemodynamic significance.
PREMATURE VENTRICULAR CONTRACTION (PVC)
Premature and wide QRS, no P wave, T wave opposite to QRS:
Multifocal PVCs: Different-shaped PVCs in same strip.
Bigeminy: Coupled beat (sinus, PVC, sinus, PVC).
Trigeminy (sinus, sinus, PVC, sinus, sinus, PVC).
Couplets (sinus, sinus, PVC, PVC, sinus, sinus).
May be normal if they are uniform and ↓ with exercise.
ATRIAL FLUTTER
A rapid atrial rate (∼300 bpm) with a varying ventricular rate, depending on degree of block (ie, 2:1, 3:1).
Sawtooth pattern (II, III, aVF, V1).
Normal QRS.
Usually suggests significant pathology (atrial enlargement).
ATRIAL FIBRILLATION
Very fast atrial rate (350–600 bpm).
Irregularly irregular ventricular response.
No P waves; normal QRS.
Usually suggests significant pathology.
VENTRICULAR TACHYCARDIA
Series of 3++ PVCs with a heart rate between 120 and 200 bpm.
Wide, unusually shaped QRS complexes.
T waves in opposite direction of QRS complex.
Usually suggests significant pathology.
VENTRICULAR FIBRILLATION
Very irregular QRS complexes.
The rate is rapid and irregular.
This is a terminal arrhythmia because the heart cannot maintain effective circulation.
SUPRAVENTRICULAR TACHYCARDIA (SVT)
Typically narrow QRS complex, no variability in R-R internal.
Reentrant tachycardia that utilizes the AV node in reentrant circuit.
Sudden onset and resolution.
Absent P waves.
Usually associated with structurally normal hearts.
SVT with aberrant conduction producing wide QRS may look like V-tach.
Axis
QRS AXIS
Examine leads I and aVF.
In lead I, count all forces above the baseline by the number of boxes (mm) and subtract all forces below baseline. If the total is +[+], the axis range is between ++90° and –90°.
Do the same in aVF. If the total is +[+], the QRS is also between 0° and ++180°.
Superimpose the ranges. Region of overlap is quadrant QRS lies in.
Find lead with isoelectric QRS complex. The axis points perpendicular to that lead.
If all leads are equiphasic, the axis is perpendicular to all leads and perpendicular to that plane. It is directed anterior or posterior and called indeterminate.
Axis Summary
0 to ++90: I++/aVF ++
0 to –90: I+/aVF–
+90 to 180: I–/aVF +
90 to 180: I–/aVF–
ABNORMAL AXES
Right axis deviation (RAD): Caused by severe pulmonary stenosis with RVH, pulmonary hypertension (HTN), conduction disturbances (RBBB). RAD is normal in a newborn because of right ventricular dominance.
Left axis deviation (LAD) with RVH is highly suggestive of AV canal. Consider especially with Down syndrome.
Mild LAD with left ventricular hypertrophy (LVH) in a cyanotic infant suggests tricuspid atresia.
QUICK WAY TO QRS AXIS
Normal = [+] in lead I, [+] in aVF:
I–, aVF– = Extreme axis deviation (direction based on Q wave).
I+, aVF– = LAD.
I, aVF+ = RAD.
P AXIS
Normal defines sinus rhythm and normally related atria (atrial situs solitus).
A P axis between 0 and –90° may result from an ectopic low right atrial pacemaker (in absence of sinus node dysfunction, it is not significant).
A P axis > +90° suggests atrial inversion or misplaced leads.
T AXIS
If differs by > 60 to 90° from QRS axis in presence of ventricular hypertrophy, it is called a “strain pattern” and may be a sign of ischemia.
If strain is present, examine left precordial leads (V5, V6) for abnormal repolarization (indicated by T-wave inversion).
LVH with strain in patients with aortic stenosis or hypertrophic cardiomyopathy is an ominous finding indicating severe disease.
Varies depending on age.
Abnormal Wave Patterns and Voltages
ABNORMAL Q WAVES
If no narrow Q waves in inferior (II, III, aVF) and leftward leads (I, V5, V6), suspect congenital heart disease (CHD) with ventricular inversion.
Q waves of new onset or of ↑ duration of previous Q waves, with or without notching of Q, may represent myocardial infarction (MI). Uncommon.
ST elevation or prolonged QTc is also supportive of MI.
Causes of ischemia and infarction: Anomalous origin of left coronary artery from pulmonary artery, coronary artery aneurysm and thrombosis in Kawasaki disease, asphyxia, cardiomyopathy, severe aortic stenosis, myocarditis, cocaine use.
A deep, wide Q wave in aVL is a marker for LV infarction. Suspect anomalous origin of left coronary artery, particularly in a child < 2 months old.
ST-T SEGMENT
End of S to beginning of T.
Causes of ST displacement: Pericarditis, cor pulmonale, pneumopericardium, head injury, pneumothorax, early ventricular repolarization, and normal atrial repolarization.
Elevation may result from ischemia or pericarditis; depression is consistent with subendocardial ischemia or effects of digoxin.
T WAVE
Peaked, pointed T waves occur with hyperkalemia, LVH, and head injury.
Flattened T waves are seen in hypokalemia and hypothyroidism.
RIGHT ATRIAL ENLARGEMENT
Peaked P waves (leads II and V1): P = > 2.5 mm (> 6 months) or > 3 mm (< 6 months).
Causes include cor pulmonale (pulmonary hypertension, RVH), anomalous pulmonary venous connection, large ASD (uncommon), Ebstein’s anomaly.
LEFT ATRIAL ENLARGEMENT
Wide P wave (notched in II, deep terminal inversion in V1): P = > 0.08 sec (< 12 months old) or > 0.10 sec (> 12 months old).
Causes include VSD, PDA, mitral stenosis.
The wider and deeper the terminal component, the more severe the enlargement.
RIGHT VENTRICULAR HYPERTROPHY (RVH)
R wave > 98% in V1 or S wave > 98% in I or V6.
↑ R/S ratio in V1 or ↓ R/S in V6.
RSR′ in V1 or V3R in the absence of complete RBBB. RSR′ with R > 15 mm (> 1 year) is characteristic of RVH secondary to right ventricular overload.
In newborns, a pure R wave in V1 > 10 mm = pressure-type RVH.
Upright T wave in V1 (> 3 days).
Presence of a Q wave in V1, V3R, V4R.
Adult pattern may occur as early as 6 years.
A qR pattern of Q wave in V1 suggests severe RVH.
Causes include ASD, TAPVR, pulmonary stenosis, tetralogy of Fallot (TOF), large VSD with pulmonary HTN, coarctation in the newborn.
Caution! The diagnosis of RVH via ECG should be made cautiously in newborns. Consider right-sided obstructive lesions (tetralogy of Fallot) in children > 6 months.
LEFT VENTRICULAR HYPERTROPHY (LVH)
R > 98% in V6, S > 98% in V1.
↑ R/S ratio in V6 or ↓ R/S in V1.
Q > 5 mm in V6 with peaked T (occurs with LV diastolic overload and denotes septal hypertrophy).
Flat or inverted T waves in lead I or V6, in presence of LVH, suggests severe LVH.
Excessive LAD supports LVH but is not sufficient to make the diagnosis.
Causes include VSD, PDA, anemia, complete AV block, aortic stenosis, systemic HTN, obstructive and nonobstructive hypertrophic cardiomyopathies.
COMBINED VENTRICULAR HYPERTROPHY (CVH)
If criteria for RVH exist and left ventricular forces exceed normal mean values for age, the patient has CVH.
If LVH present, similar reasoning may apply to the diagnosis of RVH.
In the presence of RVH, dominant RV forces diminish apparent LV forces, causing lower LV voltages (small R in V6 and small S in V1).
Large equiphasic voltages in limb leads and midprecordial leads are called Katz-Wachtel phenomenon and suggest biventricular hypertrophy.
Causes include left-to-right shunts with pulmonary HTN (large VSD) and complex structural heart disease.
Cannot diagnose ventricular hypertrophy in the absence of normal conduction (RBBB).
Causes of Sudden Cardiac Deaths in Young Athlete
Hypertrophic cardiomyopathy
Arrhythmogenic right ventricular cardiomyopathy
Congenital coronary artery anomalies
Aortic rupture with Marfan syndrome
Wolff-Parkinson-White syndrome
Congenital long QT syndrome
DECREASED QRS VOLTAGE
< 5 mm in limb leads.
Causes include pericardial effusion, pericarditis, hypothyroidism.
Sometimes normal newborns have ↓ voltages—not a concern.
WOLFF-PARKINSON-WHITE SYNDROME
Ventricular preexcitation via accessory conduction pathway through the Bundle of Kent.
Accessory pathway conducts more rapidly (than the normal AV node) but takes longer to recover.
Shortened PR interval, widened QRS caused by slurred upstroke of the delta wave.
Associated with Ebstein’s anomaly.
↑ risk of SVT and sudden death.
Treatment: Surgical ablation of accessory pathway.
BASICS OF ECHOCARDIOGRAPHY
There are four basic cross-sectional views taken of the heart with transthoracic echocardiography (TTE):
Parasternal (long and short axis).
Apical.
Subcostal (taken in the midline below the xiphoid process).
Suprasternal.
Transesophageal echocardiography employs a transducer introduced down the esophagus for enhanced imaging during cardiac surgery or catheterization.
In infants and children, coronary arteries can be evaluated nicely using TTE.
2-D Echocardiography
Cross-sectional images of the heart are seen via this method.
Parasternal views:
Long axis: Left ventricular inflow and outflow tracts.
Short axis: Aortic valve, pulmonary valve, pulmonary artery and branches, right ventricular outflow tract, atrioventricular valves, right side of heart.
Apical views: Atrial and ventricular septa, atria and ventricles, atrioventricular valves, pulmonary veins.
Subcostal views: Atrial and ventricular septa, atrioventricular valves, atria and ventricles, and pulmonary venous drainage.
Suprasternal views: Ascending and descending aorta, pulmonary artery size, systemic and pulmonary veins.
Color-Flow Doppler Echocardiography
Blood flow and direction can be seen via this method.
Red indicates blood flowing toward the transducer.
Blue indicates blood flowing away from the transducer.
When blood flow velocity exceeds a certain limit (called the Nyquist limit), the color signal is often yellow. This is indicative of high velocities that may be seen in VSDs, ASDs, and valvar regurgitation and stenosis.
M MODE ECHOCARDIOGRAPHY
In this mode, the information from one scan point is measured over time.
Motion creates a graph of depth of structures (ie, valves, ventricular wall, etc.) versus time.
This modality is used to determine cardiac chamber dimension, valve annuli size, fractional shortening and ejection fraction, left ventricular mass.
FETAL ECHOCARDIOGRAPHY
For the prenatal diagnosis of congenital heart diseases.
Allows for improved counseling and better understanding of the postnatal prognosis.
Screen at > 16 weeks.
Indications:
Fetal:
Abnormal screening obstetric ultrasound.
Extracardiac anomalies.
Chromosomal abnormalities.
↑ first-trimester nuchal translucency measurement (trisomy 21 and Turner syndrome).
Maternal (diabetes, phenylketonuria).
INTERPRETATION OF PEDIATRIC CHEST X-RAYS
Heart Size
Cardiothoracic ratio:
Measure largest width of the heart and divide by the largest diameter of the chest. A normal ratio is < 0.5.
The CXR must have a good inspiratory effort. For this reason, newborns and infants are difficult to evaluate by this method.
Cardiomegaly on CXR is most suggestive of volume overload; ECG better reflects ↑ pressure.
Cardiac Chamber Enlargement
Left atrial enlargement (LAE):
May produce a “double density” on the PA CXR.
More severe LAE can elevate the left mainstem bronchus.
Right atrial enlargement (RAE): RAE is noted most at the right lower cardiac border; however, it is difficult to diagnose by CXR alone.
Left ventricular enlargement:
The apex is seen further to the left and downward.
On lateral CXR, the posterior cardiac border is further displaced posteriorly.
Right ventricular enlargement:
VH is not seen well on PA CXR because it does not make up the cardiac silhouette.
On lateral CXR, it is noted by filling the retrosternal space.
In newborns and small infants, the upper aspects of the heart are obscured by a large “boat sail–shaped” opacity—the thymus. This organ will involute after puberty. It is often not seen in premature newborns.
Pulmonary Vascular Markings
INCREASED PULMONARY VASCULAR MARKINGS
Noted by the visualization of pulmonary vasculature in the lateral one-third of the lung field.
In an acyanotic child this could be ASD, VSD, PDA, endocardial cushion defect, or partial anomalous pulmonary venous return.
In a cyanotic child this could be transposition of the great arteries, TAPVR, hypoplastic left heart syndrome, persistent truncus arteriosus, or single ventricle.
DECREASED PULMONARY VASCULAR MARKINGS
The lung fields are dark, with small vessels.
Seen in pulmonary stenosis and atresia, tricuspid stenosis and atresia, tetralogy of Fallot.
PULMONARY VENOUS CONGESTION
Manifested as hazy lung fields.
Kerley B lines are often present.
Caused by LV failure or obstruction of the pulmonary veins.
Seen in mitral stenosis, TAPVR, cor triatriatum, hypoplastic left heart syndrome, or any left-sided obstructive lesion with heart failure.
Abnormal Cardiac Silhouettes
TETRALOGY OF FALLOT
A “boot-shaped” heart with ↓ pulmonary vascular markings is sometimes seen. The boot is due to the hypoplastic main pulmonary artery.
RVH is noted.
About 25% will have a right aortic arch.
Transposition of the Great Arteries
An “egg-shaped” heart is sometimes seen.
The narrow superior aspect of the cardiac silhouette is due to the absence of the thymus and the irregular relationship of the great arteries.
TOTAL ANOMALOUS PULMONARY VENOUS RETURN
A “snowman” shape is sometimes seen.
The left vertical vein, left innominate vein, and dilated superior vena cava create the “snowman’s” head.
RHEUMATIC FEVER
DEFINITION
Rheumatic fever is a delayed immunologic sequela of a previous group A streptococcal infection of the pharynx (not of the skin).
Cutaneous streptococcal infection is a precursor of glomerulonephritis.
Affects the brain, heart, joints, and skin.
EPIDEMIOLOGY
Although an uncommon disease in the United States, small outbreaks occur in various regions.
Peak age range: 6–15 years.
A positive family history of rheumatic fever ↑ risk.
Incidence: 0.3–3% in developed countries.
Risk of RF after untreated strep pharyngitis is 1–3%.
Patients with the infection < 3 weeks have a 0.3% risk.
Follows pharyngitis by 1–5 weeks (average: 3 weeks).
Rate of recurrent RF with subsequent strep infection may approach 65%.
Recurrence rate ↓ to < 10% over 10 years.
DIAGNOSIS
To diagnose acute rheumatic fever you must fulfill the following combination of the Jones criteria:
Two major manifestations or
One major and two minor manifestations
In addition to the major and minor manifestations, patients may appear pale and complain of abdominal pain and epistaxis.
Aschoff bodies (found in atrial myocardium) are diagnostic.
Jones Criteria (Modified)
2 major or 1 major + 2
minor
Major—J ♡ NES:
Joints—polyarthritis
♡—carditis
Nodules, subcutaneous
Erythema marginatum
Sydenham’s chorea
Minor:
Arthralgia
Fever
Elevated erythrocyte sedimentation rate (ESR) or C-reactive protein (CRP)
Prolonged P-R interval Plus
Laboratory evidence of antecedent group A strep infection (ASO titer)
CARDITIS
Incidence: 50% of patients.
Clinical presentation:
Tachycardia is common.
Heart murmur, most commonly due to valvulitis of the following (in order of decreasing frequency):
Mitral valve regurgitation
Aortic valve regurgitation
Tricuspid valve regurgitation—less common.
Pericarditis (a friction rub may be heard).
Cardiomegaly.
CHF (a gallop may be heard).
ARTHRITIS
Most common manifestation, affecting 70%.
Usually affects the large joints, but can affect the spine and cranial joints.
Migratory in nature, affecting a new joint as other affected joints resolve (can affect more than one joint at a time).
Joints are red, warm, swollen, and very tender, particularly if moved.
Responds well to aspirin therapy (give once diagnosis is confirmed).
Duration is usually < 1 month, even without treatment.
Absence of tachycardia or murmur usually excludes the diagnosis of myocarditis.
CHOREA
Incidence: 15% of patients; most commonly prepubertal girls.
Movements last on average 7 months before slowly diminishing (can last up to 17 months).
Characteristics:
Initial emotional lability: Behaviors characteristic of attention deficit/hyperactivity disorder (ADHD) and obsessive-compulsive disorder (OCD) have been noted to precede the movement disorder.
Loss of motor coordination.
Spontaneous, purposeless movement.
Motor weakness.
Rheumatic fever can cause long-term valvular disease, both stenosis and insufficiency.
ERYTHEMA MARGINATUM
Incidence: < 10% of patients.
Pink, erythematous macular rash.
Often has a clear center and serpiginous outline.
Nonpruritic.
Evanescent and migratory.
Disappears when cold.
Reappears when warm.
Found primarily on the trunk and proximal extremities.
SUBCUTANEOUS NODULES
Incidence: 2–10% of patients.
Hard, painless, small (0.5–1 cm) swellings over bony prominences, primarily the extensor tendons of the hand.
Can also be found on the scalp and along the spine.
Not transient, lasting for weeks.
If a patient’s arthritis doesn’t improve within 48 hours of therapeutic aspirin therapy, he or she probably does not have rheumatic fever.
DIAGNOSIS
Streptococcal antibody tests are the most reliable evidence of preceding group A strep infection → acute rheumatic fever.
Antistreptolysin O (ASO) titer is the most commonly used. It is elevated in 80% of patients with acute rheumatic fever (ARF) and 20% of normal individuals.
Other antibody tests exist (antihyaluronidase, antistreptokinase, anti-deoxyribonuclease B) wherein at least one will be positive in 95% of patients with ARF.
Positive throat cultures and “rapid strep tests” are less reliable because they do not differentiate acute infection versus chronic carrier state.
The chorea of rheumatic fever is known as Syndenham’s chorea or St. Vitus’ dance.
TREATMENT
Upon diagnosis, the patient should receive benzathine penicillin G 1.2 million units IM to eradicate the streptococci (if < 27 kg = 600,000 U).
Patients allergic to penicillin can receive 4 days of erythromycin 40 mg/kg/day.
Prophylaxis should be initiated:
Benzathine penicillin G 1.2 million units IM every 3–4 weeks or
Penicillin 200,000 units PO three times per day or
Sulfadiazine 1 g PO once per day
Length of prophylaxis is undetermined but often advocated at least throughout adolescence, if not indefinitely. Obviously, compliance becomes a difficult issue.
Seventy-five percent of patients recover within 6 weeks, and less than 5% are symptomatic beyond 6 months. Seventy percent of those with carditis recover without permanent cardiac damage.
Erythema marginatum is never found on the face.
ENDOCARDITIS
A 6-year-old girl with PDA develops fever and anorexia. Her Hgb is 9; she has hematuria, ↑ ESR, positive rheumatoid factor (RF), and immune complexes are present. Think: Bacterial endocarditis.
Predisposition: Congenital heart disease. Greatest risk: Systemic-pulmonary arterial communications such as patent ductus arteriosus. Chronic anemia, microscopic hematuria, elevated ESR, positive rheumatoid factor, circulating immune complexes, and low complement levels are all may be present in infective endocarditis.
ETIOLOGY
α -Hemolytic streptococci are most common (70%).
Streptococcus viridans.
Staphylococcus aureus is also common, accounting for 20% of cases.
If felt to be secondary to cardiac surgery complications, Staphylococcus epidermidis, gram-negative bacilli, and fungi should be considered.
Culture-negative endocarditis: Coxiella burnetii or Bartonella.
Most endocarditis is left-sided.
Right-sided endocarditis is associated with IV drug use.
Subcutaneous nodules are also found in connective tissue diseases such as systemic lupus erythematosus (SLE) and rheumatoid arthritis.
PATHOPHYSIOLOGY
Most likely to occur on congenitally abnormal valves, valves damaged by rheumatic fever, acquired valvular lesions, prosthetic replacement valves, and any cardiac defect → turbulent blood flow.
SIGNS AND SYMPTOMS
Fever is most common.
New or changing heart murmur.
Chest pain, dyspnea, arthralgia, myalgia, headache.
Embolic phenomena:
Hematuria with red cell casts.
Acute brain ischemia.
Roth spots, splinter hemorrhages, Osler’s nodes, Janeway lesions (less common in children).
Subcutaneous nodules in rheumatic fever have a significant association with carditis.
PREDISPOSING CONDITIONS
High risk:
Prosthetic cardiac valves.
Previous bacterial endocarditis (due to scar formation on valve).
Congenital heart disease—complex cyanotic types.
Surgical pulmonary-systemic shunts.
Moderate risk:
Congenital cardiac diseases not in high and low risk.
Acquired valvular dysfunction.
Rheumatic heart disease, Libman-Sacks valve, antiphospholipid syndrome–associated valve disease.
Hypertrophic cardiomyopathy.
Complicated mitral valve prolapse (valvular regurgitation, thickened valve leaflets).
Low risk:
Isolated ASD, secundum type.
Surgically repaired cardiac defects > 6 months postoperative (ASD, VSD, PDA).
Heart murmurs with normal echocardiogram (physiologic or functional, flow murmurs).
Systemic diseases without cardiac valve involvement:
Kawasaki disease: Normal echo only.
Rheumatic heart disease: Normal echo only.
Cardiac pacemakers and implantable defibrillators.
A history of sore throat or scarlet fever is insufficient evidence for rheumatic fever without a positive strep test.
Carditis is the only manifestation of rheumatic fever that can cause permanent cardiac damage. Therefore, once definitively diagnosed, anti-inflammatory therapy (with prednisone in extreme cases, or aspirin) should be started.
DIAGNOSIS
Four sets of blood cultures over 48 hours from different sites.
Most common findings:
Positive blood cultures
Elevated ESR
Hematuria
Anemia
Echocardiographic evidence of vegetations or thrombi is diagnostic.
Janeway lesions—painless Osler’s nodes—painful
TREATMENT
Four to eight weeks of organism-specific antibiotic therapy.
Surgery is necessary when endocarditis is refractory to medical treatment. Also considered in cases of prosthetic valves, fungal endocarditis, and hemodynamic compromise.
Antibiotic prophylaxis is necessary for children with structural heart disease and other predisposing conditions.
Risk Factors for Endocarditis
Previous endocarditis
Dental procedures
Gastrointestinal and genitourinary procedures
IV drug use (usually affects the tricuspid valve)
Indwelling central venous catheters
Prior cardiac surgery
PROPHYLAXIS RECOMMENDATIONS
Prophylaxis is recommended with:
Most dental and periodontal procedures.
Tonsillectomy or adenoidectomy.
Rigid bronchoscopy or surgery involving gastrointestinal (GI) or upper respiratory mucosa.
Gallbladder surgery.
Catheterization in setting of urinary tract infection, cystoscopy, urethral dilation.
Urinary tract surgery.
Incision and drainage of infected tissues.
Prophylaxis is not usually recommended with:
Intraoral injection of local anesthetic.
Shedding of primary teeth.
Tympanostomy tube insertion.
Endotracheal tube insertion.
Bronchoscopy with flexible bronchoscope.
Transesophageal echo.
Cardiac catheterization.
Cesarean section (only when no infection present).
GI endoscopy, with or without biopsy (prophylaxis for high-risk patients).
Genitourinary (GU) procedures with no infection present (except those above).
Circumcision.
MYOCARDITIS
ETIOLOGY
Most often caused by viruses. Coxsackieviruses and echoviruses are most common. Recent evidence suggests adenovirus as a common etiology.
Immune-mediated diseases (eg, acute rheumatic fever, Kawasaki disease).
Collagen vascular diseases.
Toxic ingestions.
EPIDEMIOLOGY
Clinically recognizable myocarditis is rare in the United States.
SIGNS AND SYMPTOMS
Presentation depends on the degree of myocardial injury.
Ranges from asymptomatic to fulminant CHF.
Common symptoms are fever, dyspnea, upper respiratory symptoms, vomiting, and lethargy.
CHF should be considered if patient is tachycardic and tachypneic and has a gallop on auscultation.
DIAGNOSIS
ECG findings: Low voltages, S-T changes, prolonged QT interval, premature beats.
Radiology: Chest radiographs will show cardiomegaly.
Echocardiography: Chamber enlargement is present with impaired ventricular function.
TREATMENT
First, treat the underlying cause (ie, antibiotics if bacterial).
Since it is most often viral, treatment is largely supportive. Rest and activity limitation is important.
Treatment of CHF may be necessary (ie, diuretics, inotropic agents if severely ill). Gamma globulin also has been effective.
PERICARDITIS
ETIOLOGY
Viral (most common).
Bacterial infection (also common): acute rheumatic fever, S aureus, Haemophilus influenzae, Neisseria meningitidis, streptococci, tuberculosis.
Complications from heart surgery.
Collagen vascular diseases.
Uremia.
Medications (ie, dantrolene, oncology agents).
SIGNS AND SYMPTOMS
Precordial pain with radiation to the shoulder and neck (often relieved by standing).
Pericardial friction rub on auscultation.
Signs of cardiac tamponade:
Distant heart sounds.
Tachycardia.
Pulsus paradoxus.
Hepatomegaly and venous distention.
Digitalis is typically not given in pericarditis, as this blocks the compensatory tachycardia the heart utilizes to overcome ↓ venous return.
DIAGNOSIS
CXR: A pear- or water bottle–shaped heart indicates a large effusion.
Echocardiography is diagnostic (can also detect tamponade).
TREATMENT
Treat the underlying disease process.
Supportive treatment for viral etiologies.
Pericardiocentesis is indicated if effusion is present.
Urgent drainage is indicated when symptoms of tamponade are present.
Onset of CHF is dependent on the fall of pulmonary vascular resistance and the subsequent ↑ left-to-right shunting.
CONGESTIVE HEART FAILURE (CHF)
ETIOLOGY
Caused from either congenital heart disease (CHD) or acquired heart disease.
CHD: Most common cause is from volume or pressure overload.
VSD, PDA, and endocardial cushion defects are the most common causes of CHF in the first 6 months of life.
ASD can cause CHF in adulthood if unrepaired.
Acquired heart disease: Potential causes of CHF are metabolic abnormalities (ie, hypoxia, acidosis, hypoglycemia, hypocalcemia), myocarditis, rheumatic fever with carditis, cardiomyopathy, and drug toxicity.
A left-to-right shunt usually takes about 6 weeks to become significant enough to stress the left ventricle.
SIGNS AND SYMPTOMS
Often similar symptoms to those found in respiratory illnesses: tachycardia, tachypnea, shortness of breath, rales and rhonchi, intercostal retractions.
Poor weight gain/poor feeding.
Cold sweat on forehead.
Older children develop peripheral edema.
Gallop on auscultation.
Hepatomegaly, jugular venous distention (JVD).
Use of diuretics in CHF is preferred to salt and fluid restriction.
DIAGNOSIS
CXR: Cardiomegaly, evidence of pulmonary edema.
Echo: Enlarged ventricular chamber, impaired ventricular function.
Watch out for hypokalemia, as ↑ potassium is lost with some diuretic use.
TREATMENT
Treat the underlying cause (ie, surgical correction of CHD, correction of metabolic defects).
Oxygen can be used if patient is hypoxic or in respiratory distress.
Medication:
Digitalis is used to improve ventricular function. Contraindicated in complete heart block and hypertrophic cardiomyopathy.
Diuretics are used to ↓ volume overload and pulmonary edema. Most common are the “loop diuretics” (ie, furosemide).
Afterload-reducing agents (ie, angiotensin-converting enzyme [ACE] inhibitors, calcium channel blockers, nitroglycerin) are used to dilate peripheral vasculature and thus ↓ the work on the heart.
Hypokalemia can precipitate digitalis toxicity.
VASCULITIDES
Henoch-Schönlein Purpura
Immune-mediated vasculitis that affects the GI tract, joints, and kidneys and causes a characteristic rash (see Chapter 20).
Palpable purpura.
Most often occurs in winter months, following a group A streptococcal upper respiratory infection (URI).
GI involvement is most significant, → vomiting and upper and lower GI bleeding.
Renal involvement, in the form of glomerulonephritis, with RBC casts, can progress to acute renal failure. More common is chronic proteinuria, which can be a late sequelae.
Treatment is supportive, with full recovery within 4–6 weeks.
Kawasaki Disease
A 2-year-old boy with fever for 7 days, often reaching 104°F (40°C), develops nonexudative conjunctival injection bilaterally; intensely erythematous lips, palms, and soles; generalized erythema multiforme; and an enlarged, tender anterior cervical lymph node. Blood cultures are sterile, and platelets are ↑. Think: Kawasaki disease.
Beware of his risk for coronary aneurysms and MI. Fever lasting for 5 or more days is the hallmark that must be present with at least four of the following features: conjunctival injection, oropharyngeal mucous membrane changes, extremity changes, polymorphous rash, and cervical lymphadenopathy.
DEFINITION
Also known as mucocutaneous lymph node syndrome.
Most common acquired heart disease in children.
ETIOLOGY
Acute vasculitis of unknown etiology.
EPIDEMIOLOGY
Affects infants and young children (> 80% under age 4 years).
More common in Asians than other racial groups.
More common in males than females (ratio 1.5:1).
Most common in winter/spring months.
SIGNS AND SYMPTOMS
Sterile pyuria.
Aseptic meningitis.
Thrombocytosis.
Desquamation of fingers and toes.
Elevated ESR or CRP.
Most significant sequelae:
Coronary aneurysms (usually resolve within 12 months of adequate therapy).
Pericardial effusion.
CHF.
DIAGNOSIS
Diagnostic criteria: Fever for > 5 days plus ≥ 4 of the following:
1. Bilateral conjunctivitis (without exudate).
2. Mucocutaneous lesions (“strawberry” tongue; dry, red, cracked lips; diffuse erythema of oral cavity).
3. Changes in upper and lower extremities (erythema and/or edema of hands/feet).
4. Polymorphic rash (usually truncal).
5. Cervical lymphadenopathy (> 1.5 cm in diameter), usually unilateral.
Echocardiogram: Initial study at diagnosis to establish baseline and to evaluate for early coronary aneurysms; follow-up echo to establish presence or absence.
TREATMENT
Used to prevent cardiac sequelae.
Intravenous immune globulin (IVIG): Usually one dose of IVIG, 2 g/kg over 10–12 hr. Reduces incidence of coronary artery dilation (< 3%).
High-dose aspirin (80–100 mg/kg/day divided in four doses) until 48–72 hr after defervescence.
If no coronary artery abnormality, low-dose aspirin (3–5 mg/kg/day as a single daily dose) for 6–8 weeks or until platelet count and ESR are normal.
If coronary artery abnormality, continue indefinitely in consultation with a pediatric cardiologist. Aspirin is reduced after the patient is afebrile for 48 hours.
Use of steroids remains controversial and typically reserved for cases refractory to repeat doses of IVIG.
Polyarteritis Nodosa
DEFINITION
A necrotizing inflammation of the small and medium-sized muscular arteries.
SIGNS AND SYMPTOMS
Prolonged fever, weight loss, malaise, subcutaneous nodules on extremities.
Various rashes can be associated with this condition.
Respiratory symptoms: Rhinorrhea, congestion.
Often waxes and wanes.
Gangrene of distal extremities is found in severe disease.
Hypertension and abdominal pain can be important clues in polyarteritis nodosa.
DIAGNOSIS
No diagnostic tests.
Associated with abnormal cell counts (thrombocytosis, leukocytosis), abnormal urine analysis, elevated acute-phase reactants, perinuclear antineutrophil cytoplasmic antibody (p-ANCA).
Conclusive with findings of medium-sized artery aneurysms.
Echocardiographic evidence of coronary artery aneurysms is diagnostic if other clinical evidence is present.
TREATMENT
Corticosteroids suppress the clinical manifestations.
Cyclophosphamide or azathioprine may be required to induce remission.
Takayasu’s Arteritis
DEFINITION
Also known as aortoarteritis.
Chronic inflammatory disease involving:
Aorta.
Arterial branches from the aorta.
Pulmonary vasculature.
Takayasu’s arteritis is also known as “pulseless disease.”
PATHOPHYSIOLOGY
Lesions are segmental and often obliterative.
Aneurysmal and saccular dilation also occur.
Thoracoabdominal aorta is the predominantly affected site in the pediatric population.
EPIDEMIOLOGY
Most patients are female, aged 4–45 years.
SIGNS AND SYMPTOMS
A significant number of patients experience LV dysfunction and CHF (even in the absence of coronary artery involvement, HTN, or valvular abnormalities).
A lymphocytic infiltration consistent with myocarditis is present in about 50% of patients.
Other symptoms include fever, polyarthralgias, polyarthritis, and loss of radial pulsations.
Essentially, Takayasu’s arteritis is giant cell arteritis of the aorta (and large branches).
TREATMENT
Corticosteroids may induce remission.
Wegener’s Granulomatosis
DEFINITION
A rare vasculitis of both arteries and veins → widespread necrotizing granumolas.
EPIDEMIOLOGY
Most common in adults, although occurrence in children has been described.
Children with cyanotic heart disease are at ↑ risk for strokes and scoliosis.
SIGNS AND SYMPTOMS
Rhinorrhea, nasal mucosa ulcers, sinusitis.
Hematuria.
Cough, hemoptysis, pleuritis.
Heart involvement: Granulamatous inflammation of cardiac muscle causing arrhythmias.
DIAGNOSIS
Antineutrophil cytoplasmic antibodies (c-ANCA) are present.
ESR is greatly elevated.
Organ biopsy (kidney and/or lung) may be essential to establish early diagnosis.
TREATMENT
Corticosteroids alone may be unsuccessful.
Cyclophosphamide or azathioprine is recommended (have changed a once uniformly fatal disease into an excellent prognosis).
Central Cyanosis versus Acrocyanosis
Central cyanosis:
Involves mucous membranes.
Always pathologic in a newborn.
Cyanosis in neonates is almost always due to either pulmonary or cardiac disease.
> 5 mg/dL of deoxyhemoglobin.
Acrocyanosis:
Involves distal extremities.
Normal in newborns.
Peripheral cyanosis is the result of acrocyanosis, exposure to cold, and ↓ peripheral perfusion.
Cyanotic Heart Defects
Five T’s and a P
Tetralogy of Fallot
Transposition of the great vessels
Truncus arteriosus
Tricuspid atresia
Total anomalous pulmonary venous return (obstructive)
Pulmonic atresia
CYANOTIC HEART DEFECTS
See Figure 13-2.
Tetralogy of Fallot (TOF)
The most common form of cyanotic CHD in the postinfancy period.
DEFINITION
Four anomalies constitute the tetralogy:
1. Right ventricular outflow tract obstruction (RVOTO).
2. VSD.
3. Aortic override.
4. RVH.
Two key features are required for diagnosis of TOF:
VSD (typically large enough to equalize pressures in right and left ventricles).
RVOTO (eg, pulmonary stenosis).
Aortic override is variable.
RVH is secondary to the RVOTO.
ETIOLOGY
Prenatal factors associated include maternal rubella or viral illness.
PATHOPHYSIOLOGY
RVOTO dictates degree of shunting:
Minimal obstruction: → ↑ pulmonary blood flow as pulmonary vascular resistance (PVR) ↓, → CHF.
Mild obstruction: Hemodynamic balance pressure between right and left ventricles is equal, thus no net shunting (“pink tet”).
Severe obstruction: ↓ pulmonary blood flow, → cyanosis.
FIGURE 13-2. Basic echocardiography views.
A. Top left: This frame, taken from a normal subject, is a parasternal long-axis (P L Ax) view taken slicing the heart from a parasternal location at the fourth left interspace, subtending a sector with the right ventricle (RV) anteriorly. The sound beams then pass through the ventricular septum and the aorta (AO), the left ventricular cavity (LV), and the left ventricular posterior wall. Behind the ascending aortic root is the left atrium (LA). Posterior to the heart behind the pericardium, the descending aorta (DAO) can be seen running in its cross-section, indicating how far from the sagittal body plane this image is as the descending aorta runs on the left of the spine. Bottom left: From the same normal subject in the parasternal short-axis (P S Ax) view from the third intercostal space. The sector subtends the right side of the heart as it winds around the aortic root (AO) in the center of image. The right atrium (RA) is separated from the right ventricle (RV) by the tricuspid valve. The pulmonary artery (PA) is separated from the right ventricle by the pulmonary valve. The cusps of the aortic valve can also be identified in this figure. The pulmonary artery bifurcates into its left (L) and right branches. Top right, bottom right: These parasternal short-axis (P S Ax) views taken from the same normal subject are sequential scans through the heart from the top to the bottom (from the cranial-to-caudal direction). The top frame represents a short-axis view of the entire right heart. In the center, the aortic valve (AO) cusps are seen in their open position, demonstrating a tri-leaflet aortic valve. Posteriorly, the left atrium (LA), with the left atrial appendage (LAA) extending to the left side of the heart, is observed. The interatrial septum separates the left atrium from the right atrium (RA). The tricuspid valve separates the right atrium from the right ventricle (RV). In the bottom frame with the caudal scan, the right (RV) and left (LV) ventricles are seen. The ventricular septum is seen between the two ventricles. The mitral valve (MV) is seen in its open position with the anterior cusp (arrow) at the top and the posterior cusp (arrow) at the bottom.
B. This is a series of apical four-chamber views (A 4 Ch) from a normal subject, demonstrating the scan from the anterior to the posterior aspect of the heart (from the apex to base). The electrocardiogram shown on the bottom indicates the timing within the cardiac cycle. The top frame is taken in systole. A left pulmonary vein (PV) can be seen entering the left atrium (LA). The right atrium (RA) is separated from the left atrium (LA) by the faint echo of the interatrial septum. The aortic root (AO) can be seen to be arising out of the heart, and the left and right ventricles (LV, RV) can be seen separated from their respective atria by the tricuspid and mitral valves in the closed position, and from each other by the ventricular septum. The second frame, taken with more caudal scanning, demonstrates the descending aorta in cross-section, the pulmonary veins (PV) from the left and the right (arrows), the atria, and the ventricles. This is an end-systolic frame, as seen from the electrocardiogram. The third frame, taken with most caudal scanning, demonstrates the descending aorta (DAO) posteriorly, and a small portion of the left atrium (LA) with a coronary sinus (CS) running inferiorly at the crux of the heart. The other labels are as for the previous panels. The fourth frame shows the aortic arch from the suprasternal notch sagittal view (SSN, SAG) in a normal infant. The scan comes from the suprasternal notch area, and the sector subtends the innominate vein (IV) superiorly, as it crosses in front of the ascending aorta (AAO). The whole arch is seen from the ascending aorta to the descending aorta (DAO). The brachiocephalic artery (BCA) and left carotid artery (LCA) can be seen arising from the aortic arch. The circular right pulmonary artery can be seen running under the arch (RPA). The label obscures the area of the right bronchus, lying between the aortic arch and the right pulmonary artery. Anteriorly, the thymus (Th) is identified.
C. These images from a normal subject are taken with the subcostal transducer position in coronal and sagittal (SAG) planes. The scans pass from the subcostal region through the liver and diaphragm, and into the heart. Right panels: In the top right panel with posterior angulation, the left ventricle (LV) and right ventricle (RV) are identified. The aorta (AO) arises from the left ventricle, separated from it by the aortic valve; the right atrium (RA) and right ventricle (RV) can be identified. The bottom right panel, taken in an orthogonal cut in the sagittal plane, demonstrates the left ventricle (LV) cut in cross-section with its papillary muscles; the right ventricle (RV) and pulmonary artery (PA) can be seen wrapping around the left ventricle. Left panels: These subcostal oblique cuts demonstrate the exit of the aorta (AO) and the pulmonary artery (PA) from their respective ventricles, the left ventricle (LV) and the right ventricle (RV). In the upper left panel, the aorta (AO) can be seen arising from the left ventricle (LV) and arching toward the left side over the main pulmonary artery (PA). In the bottom left panel, taken with an orthogonal view and more anterior angulation, the right-sided structures, right atrium (RA), right ventricle (RV), main (M) pulmonary artery, and right (R) pulmonary artery can be seen as they surround the aortic valve (AO). (Reproduced, with permission, from Rudolph’s Pediatrics, 20th ed. Appleton & Lange, 1996.)
EPIDEMIOLOGY
Most common cyanotic heart defect in children who survive infancy.
SIGNS AND SYMPTOMS
Failure to thrive (FTT) (if diagnosed late).
“Conotruncal facies.”
Variable cyanosis (clubbing later if unrepaired).
RV impulse; occasional thrill; single S2, systolic ejection murmur at the upper left sternal border with or without ejection click.
Squatting is a common posture in older, unoperated children with TOF:
Often occurs after exercise.
Causes trapping of desaturated blood in the lower extremities and ↑ systemic vascular resistance (SVR) while the RVOTO remains fixed. Thus, it:
↓ right-to-left shunting.
↑ pulmonary blood flow.
↑ arterial saturation.
“TET SPELLS”
Most common: 2–6 months of age.
Occur in the morning or after a nap when SVR is low.
Precipitating factors:
Stress
Drugs that ↓ SVR
Hot baths
Fever
Exercise
Mechanism: Unknown, but likely due to ↑ cardiac output with fixed RVOT, → ↑ right-to-left shunting, which ↑ cyanosis
If prolonged or severe: Syncope, seizures, cardiac arrest.
DIAGNOSIS
CXR (Figure 13-3).
“Boot-shaped heart.”
↓ pulmonary vascular markings.
Right aortic arch (25%).
CXR with the boot shape, ↓ pulmonary vascular markings, and a right aortic arch. Think: Tetralogy of Fallot.
TREATMENT
Patient’s clinical status may prevent definitive repair initially.
Shunting (ie, Blalock-Taussig shunt) is often used when pulmonary stenosis is severe and an alternative route for blood to reach the lungs is necessary.
Complete repair entails:
VSD closure.
Relief of RVOTO.
Ligation of shunts.
ASD/patent foramen ovale (PFO) closure.
Without repair of TOF, mortality is:
50% by 3 years
90% by 20 years
95% by 30 years
FIGURE 13-3. Chest x-ray in tetralogy of Fallot.
Arrows indicate right-sided aortic arch and upper thoracic aorta. Dashed lines indicate right-sided aortic indentation on the air bronchogram. (Reproduced, with permission, from Rudolph CD, et al (eds). Rudolph’s Pediatrics, 21st ed. New York: McGraw-Hill, 2002: 1821.)
Transposition of the Great Vessels
The most common cyanotic heart lesion in the newborn period.
PATHOPHYSIOLOGY
This lesion occurs when, in the development of the heart, the primitive heart loops to the left instead of the right and the following result (see Figure 13-4):
Aorta originates from the RV.
Pulmonary artery originates from LV.
Aorta is anterior; pulmonary trunk is posterior.
Right and left hearts are in parallel:
Pulmonary venous return goes to the pulmonary artery via left ventricle.
Systemic venous return goes to the aorta via the right ventricle.
The presence of a VSD, ASD, or PDA is essential to survival.
A PDA alone is usually not sufficient to allow adequate mixing in the extrauterine environment.
Cyanosis becomes more prevalent with the closure of the PDA.
Presentation: CHF in the first week of life.
CXR: Egg-shaped heart with a narrow mediastinum. Cardiomegaly with ↑ pulmonary vascular marking.
EPIDEMIOLOGY
Most common cyanotic congenital heart defect presenting in the neonatal period.
|
Intact Ventricular Septum (with no valve abnormality) |
With VSD (a large VSD allows adequate mixing) |
SIGNS AND SYMPTOMS
Early cyanosis, a single S2, and no murmur.
An intact atrial septum or very restrictive PFO is a medical emergency.
Symptoms are related to ↑ pulmonary blood flow, with CHF sometimes occurring early.
May have little cyanosis.
FIGURE 13-4. Transposition of the great vessels.
“Egg on a string”—spinal column serving as the string and the globular presentation of the heart as the egg. (Reproduced, with permission, from Moller JH, Neal WA. Fetal, Neonatal, and Infant Cardiac Disease, 2nd ed. Appleton & Lange, 1992: 532.)
DIAGNOSIS
ECG will be normal initially, but will demonstrate right ventricular hypertrophy by 1 month.
CXR: “Egg on a string.”
ECG: Right or biventricular hypertrophy.
BAS if VSD does not allow adequate mixing.
Transposition of the great vessel: “Big blue baby” as intrauterine growth is normal.
TREATMENT
Patient is “ductal dependent” and will require prostaglandin E1 (PGE1) to keep the PDA patent.
Early balloon atrial septostomy (BAS) is necessary to allow mixing of oxygenated and deoxygenated blood.
Arterial switch procedure is definitive.
PA band to control ↑ pulmonary blood flow.
Arterial switch with VSD closure is definitive.
Truncus Arteriosus
DEFINITION
A persistent truncus is a single arterial trunk that emerges from the ventricles, supplying the coronary, pulmonary, and systemic circulations (see Figure 13-5).
Association: DiGeorge syndrome.
TYPES
I: Short common pulmonary trunk arising from right side of common trunk, just above truncal valve.
II: Pulmonary arteries (PAs) arise directly from ascending aorta, from posterior surface.
III: Similar to type II, with PAs arising more laterally and more distant from semilunar valves.
FIGURE 13-5. Truncus arteriosus.
PATHOPHYSIOLOGY
The valve has two, three, or four leaflets and is usually poorly functioning.
The truncus overrides a VSD.
SIGNS AND SYMPTOMS
Presentation: CHF and cyanosis in first week.
Initial left-to-right shunt symptoms:
Dyspnea.
Frequent respiratory infections.
FTT.
If pulmonary vascular resistance ↑, cyanosis ↑.
Second heart sound is prominent and single due to the single semilunar valve.
Peripheral pulses are strong, often bounding.
Often, a systolic ejection click can be appreciated.
DIAGNOSIS
CXR shows cardiomegaly and ↑ pulmonary vascular markings.
TREATMENT
Surgery must occur before patient develops significant pulmonary vascular disease (usually 3–4 months of age).
VSD is surgically closed, leaving the valve on the LV side.
The pulmonary arteries are freed from the truncus and are connected to a valved conduit (Rastelli procedure), which will serve as the new pulmonary trunk.
Hypoplastic Left Heart Syndrome (HLHS)
DEFINITION
The syndrome consists of the following (see Figure 13-6):
Aortic valve hypoplasia, stenosis, or atresia with or without mitral valve stenosis or atresia.
FIGURE 13-6. Hypoplastic left heart syndrome.
Note small size of left ventricle.
Hypoplasia of the ascending aorta.
LV hypoplasia or agenesis.
Mitral valve stenosis or atresia.
The result is a single (right) ventricle that provides blood to the pulmonary system, the systemic circulation via the PDA, and coronary system via retrograde flow after crossing the PDA.
In utero:
All systemic blood flow is ductus dependent.
Pulmonary resistance > systemic vascular resistance.
Normal perfusion pressure is maintained with right-to-left shunt through PDA and pulmonary resistance.
At birth:
PDA closes.
Systemic vascular resistance > pulmonary resistance.
PDA closure + hypoplastic LV = ↓ cardiac output and ↓ aortic pressure → circulatory death and metabolic acidosis.
PDA dependent until intervention is undertaken.
EPIDEMIOLOGY
The second most common congenital heart defect, presenting in the first week of life (and the most common cause of death from CHD in the first month).
SIGNS AND SYMPTOMS
Pulses range from normal to absent (depending on ductal patency).
Hyperdynamic RV impulse.
Single S2 of ↑ intensity.
Gallop at apex due if there is heart failure.
Nonspecific systolic murmur at left sternal border (LSB).
Skin may have a characteristic grayish pallor.
DIAGNOSIS
CXR: Cardiomegaly with globular-shaped heart; ↑ pulmonary vascular markings, pulmonary edema.
Echocardiogram is diagnostic.
TREATMENT
No intervention: Due to the high mortality and complicated surgical course of this disease, ethical dilemmas are frequent as to how far physicians should intervene.
Three-stage surgery:
Norwood procedure: The pulmonary trunk is used to reconstruct the hypoplastic aorta, and the right ventricle subsequently becomes the functional left ventricle. This leaves the pulmonary arteries connected but separated from the heart. The pulmonary blood flow is then reestablished via systemic to pulmonary conduits from the subclavian arteries to the pulmonary arteries.
Glenn procedure: The superior vena cava is connected to the right PA, restoring partial venous return to the lungs.
Fontan procedure: The inferior vena cava is anastamosed to the PAs, resulting in complete venous diversion from the systemic circulation to the lungs.
Heart transplant: This alternative occurs either as a primary intervention (if an organ is available) or after any of the previous palliative surgeries have provided maximal but ultimately insufficient benefit.
ACYANOTIC HEART DEFECTS
Left-to-right shunt (see Figure 13-7).
Subendocardial Cushion Defect
PATHOPHYSIOLOGY
Related to the ostium primum ASD, this defect results from abnormal development of the AV canal (endocardial cushions) resulting in:
A VSD.
An ostium primum ASD.
Clefts in the mitral and tricuspid valves.
EPIDEMIOLOGY
Association: Down syndrome (30% of patients with this defect have trisomy 21).
Also frequently found with asplenia and polysplenia syndromes.
Subendocardial cushion defects are associated with Down syndrome.
FIGURE 13-7. Acyanotic heart defects.
SIGNS AND SYMPTOMS
Often the result of the specific components of the accumulated defects:
Holosystolic murmur from the VSD, if restrictive.
Systolic murmur from mitral and tricuspid valve insufficiency.
High risk of developing Eisenmenger syndrome.
ECG: Superior QRS axis with RVH, right bundle branch block (RBBB), and LVH, along with a prolonged PR interval.
TREATMENT
Surgical correction is sometimes the only option (despite high risk) when patient has an unbalanced AV canal.
Some benefit from PA banding if shunting is predominantly at the ventricular level (rare).
Children with trisomy 21 often have more favorable anatomy for surgical intervention.
Atrial Septal Defect (ASD)
Ten percent of all congenital heart disease.
DEFINITION
Three types:
Secundum defect (most common—50–70%): Located in the central portion of the atrial septum.
Primum defect (about 30% of ASDs):
Located at the atrial lower margin.
Associated with abnormalities of the mitral and tricuspid valves.
Sinus venosus defect (about 10% of ASDs): Located at the upper portion of the atrial septum and often extends into the superior vena cava.
ASD is the most common congenital heart lesion recognized in adults.
EPIDEMIOLOGY
A common “co-conspirator” in CHD.
As many as 50% of patients with congenital heart defects have an ASD as one of the defects.
More common in females (male-to-female ratio 1:2).
SIGNS AND SYMPTOMS
Children with ASDs are typically asymptomatic.
Widely split and fixed S2. Murmurs are uncommon, but may occur as patient gets older. Murmur is a secondary pulmonary flow murmur.
Symptoms of CHF and pulmonary HTN occur in adults (second and third decades).
DIAGNOSIS
ECG: The left-to-right shunt may produce right atrial enlargement and RVH.
CXR: Cardiomegaly with ↑ pulmonary vascular markings.
TREATMENT
Nearly 90% will close spontaneously.
One hundred percent close if < 3 mm.
ASDs > 8 mm are unlikely to close spontaneously.
Surgical or catheter closure (via a “clamshell” or “umbrella” device) are used when indicated.
Patent Foramen Ovale (PFO)
The foramen ovale is used prenatally to provide oxygenated blood from the placenta to the left atrium.
It normally functionally closes when ↑ left atrial pressure causes the septa to press against each other (many remain “probe-patent” into adulthood).
In some children, the tissue of the foramen ovale is insufficient to cover the foramen (either from insufficient growth or becoming stretched from ↑ pressure or volume).
Some CHDs require a PFO for patient survival after birth (eg, tricuspid and mitral atresia, TAPVR).
VSD is the most common congenital heart disorder.
Ventricular Septal Defect (VSD)
A 2-month-old male born at term appeared well until 3 weeks ago, when he became dyspneic and had difficulty feeding. A loud pansystolic murmur is heard at the left lower sternal border, and ECG shows LVH and RVH.
Think: VSD.
Small VSD causes no symptoms. Large VSD may result in left-to-right shunt and pulmonary HTN. Left-sided volume overload and RVH are suggestive of a large VSD.
EPIDEMIOLOGY
The most common form of recognized congenital heart disease (30–60% of all patients with CHDs).
Usually membranous, as opposed to in the muscular septum.
Occurs in 2 per 1000 live births.
SIGNS AND SYMPTOMS
Dependent on defect size:
Small VSDs:
Usually asymptomatic.
Normal growth and development.
High-pitched, holosystolic murmur.
No ECG or CXR changes.
Large VSDs:
Can → CHF and pulmonary HTN.
May have FTT.
Lower-pitched murmur; intensity dependent on the degree of shunting.
DIAGNOSIS
ECG: LVH.
CXR: Cardiomegaly with ↑ pulmonary vascular markings.
Spontaneous closure occurs in 30–50% of VSDs.
TREATMENT
Spontaneous closure:
Muscular defects are most likely to close (up to 50%), with closure occurring during the first year of life.
Inlet and infundibular defects do not reduce in size or close.
Intervention is based on the development of CHF, pulmonary HTN, and growth failure.
Initial management with diuretics and digitalis.
Surgical closure is indicated when therapy fails.
Catheter-induced closure devices are less commonly used with VSDs than ASDs.
Endocarditis prophylaxis.
A PDA murmur is common (and normal) in newborn infants. It will usually disappear within the first 12 hours of life.
PATENT DUCTUS ARTERIOSUS (PDA)
PATHOPHYSIOLOGY
Most often a problem in premature neonates:
Left-to-right shunts are handled poorly by premature infants.
Many develop idiopathic respiratory distress syndrome.
Some progress to develop left ventricular failure.
Failure of spontaneous closure:
Premature infants: Due to ineffective response to oxygen tension.
Mature infants: Due to structural abnormality of ductal smooth muscle.
EPIDEMIOLOGY
PDA is more common in females (male-to-female ratio 1:3).
Incidence is higher at higher altitudes due to lower atmospheric oxygen tension.
Maternal rubella in the first trimester has also been implicated in PDA.
In the normal neonate, the ductus arteriosus closes primarily in response to a ductal PO2 > 50 mm Hg.
PDA closes within 15 hours after birth.
Complete closure by 3 weeks to become the ligamentum arteriosum.
Hypoxia and prematurity have a tendency to keep the ductus arteriosus patent.
SIGNS AND SYMPTOMS
Small PDAs usually are asymptomatic.
Large PDAs ↑ incidence of lower respiratory tract infections and CHF.
Machinery-like murmur.
Bounding peripheral pulses and wide pulse pressure.
If Eisenmenger syndrome results, patient may have cyanosis restricted to the lower extremities.
TREATMENT
Indomethacin: Used in premature infants. Inhibits prostaglandin synthesis, → closure.
Catheter closure via devices such as double-umbrella devices and coils in older children.
Surgical ligation and division via a left lateral thoracotomy.
An occasional complication is recurrent laryngeal nerve injury → hoarseness.
Eisenmenger syndrome is a contraindication to surgery.
Subacute bacterial endocarditis (SBE) is more common in small PDAs than large ones.
PDA-DEPENDENT CONGENITAL HEART ABNORMALITIES
PDA-dependent congenital heart abnormalities include:
Tetralogy of Fallot
Tricuspid atresia
TAPVR with obstruction
Aortic coarctation (severe)
Infective endocarditis is the most common complication of PDA in late childhood.
Pulmonic atresia
Hypoplastic left heart
Prostaglandin E1 (PGE1) can be potentially lifesaving in a cyanotic newborn with PDA-dependent congenital heart abnormalities.
CHD presenting in first 2–3 weeks of life are usually due to ductal-dependent lesions.
INDICATIONS FOR PGE1 ADMINISTRATION
Critically ill newborn with:
Suspected ductal-dependent lesion.
Suspected LV outflow tract obstruction.
Dose:
0.05 to 0.1 μg/kg/min (to reopen the ductus).
0.01 μg/kg/min (to maintain ductal patency).
Side effects:
Apnea: Endotracheal intubation prior to transport.
Fever, hypotension, and seizures.
Do not delay PGE1 administration in critically ill neonates with suspected ductal-dependent lesion pending definitive cardiac diagnosis.
Eisenmenger Syndrome
Can occur in unrepaired left-to-right shunts (ie, VSD) that cause an ↑ pressure load on the pulmonary vasculature.
Pressure overload on the pulmonary vasculature can result in irreversible changes in the arterioles.
This develops into pulmonary vascular obstructive disease, usually over several years.
The pulmonary HTN reduces the left-to-right shunt and previous LVH often resolves.
Persistent HTN maintains an enlarged right ventricle and can dilate the main pulmonary segment (this becomes evident on CXR).
Avoidance of this condition via surgical correction of CHD is essential, as it causes irreversible changes.
CONGENITAL VALVULAR DEFECTS
See Figure 13-8.
Tricuspid Atresia
DEFINITION
RV inlet is absent or nearly absent:
Eighty-nine percent have no evidence of tricuspid valve tissue, only dimple.
Seven percent have a membranous septum forming part of the right atrial floor.
Three percent are Ebstein’s.
One percent have a tiny, imperforate valvelike structure.
FIGURE 13-8. Congenital valvular defects.
Bicuspid aortic valve is the most common congenital heart defect, occurring in 1–2% of the population. This defect goes largely unrecognized.
EPIDEMIOLOGY
ASD and/or VSD is usually present.
Seventy-five percent will present with cyanosis within the first week.
SIGNS AND SYMPTOMS
LV impulse displaced laterally.
DIAGNOSIS
ECG: LVH, prominent LV forces (due to ↓ RV voltages).
TREATMENT
PGE1 to maintain ductal patency.
Surgical intervention.
Modified Blalock-Taussig (BT) shunt.
Glenn procedure, followed by Fontan procedure.
Pulmonary Atresia (with Intact Ventricular Septum)
SIGNS AND SYMPTOMS
Cyanosis within hours of birth (PDA closing).
Hypotension, tachypnea, acidosis.
Single S2, with a holosystolic murmur (tricuspid regurgitation).
DIAGNOSIS
ECG: ↓ RV forces and occasionally RVH.
CXR: Normal to enlarged RV with ↓ pulmonary vascular markings.
TREATMENT
PGE1 to maintain ductal patency.
Balloon atrial septostomy (sometimes).
Reconstruction of RVOT with transannular patch or pulmonary valvotomy.
ASD left open to prevent systemic venous HTN.
Aortic Stenosis
A 4-year-old boy with recurrent episodes of syncope while playing has a harsh systolic murmur radiating to the carotids, diminished cardiac pulses, and severe LVH. Think: Congenital aortic stenosis.
Angina, syncope, and congestive heart failure are the presentation of aortic stenosis. Syncope during exertion occurs due to the reduced cerebral perfusion when arterial pressure declines. However, many patients now are diagnosed before the development of these symptoms on the basis of the finding of a systolic murmur followed by echocardiography.
EPIDEMIOLOGY
Eighty-five percent of congenitally stenotic aortic valves are bicuspid.
SIGNS AND SYMPTOMS
Severe stenosis generally presents shortly after birth.
Older children may complain of chest or stomach pain (epigastric).
Patients with untreated severe aortic stenosis are at risk for syncope and sudden death.
The characteristic murmur is a crescendo-decrescendo systolic murmur.
A systolic ejection click is also common (particularly if bicuspid aortic valve).
In severe disease, paradoxical splitting of S2 occurs (split narrows with inspiration).
Supravalvular aortic stenosis is associated with idiopathic hypercalcemia.
DIAGNOSIS
Clinical findings, including ECG findings, and symptoms can be deceiving.
Echo or catheterization to evaluate pressure differences between the aorta and left ventricle is essential.
TREATMENT
Surgical or interventional balloon.
Valvotomy is most common intervention:
Indication is usually if the measured catheterization gradient is > 50 mm Hg.
High incidence of recurrent stenosis.
Valve replacement: Deferred, when possible, until patient completes growth.
Aortic Insufficiency
EPIDEMIOLOGY
Uncommon and usually associated with mitral valve disease or aortic stenosis.
SIGNS AND SYMPTOMS
A diastolic, decrescendo murmur is present at the left upper sternal border.
Presentation with symptoms indicates advanced disease.
Chest pain and CHF are ominous signs.
DIAGNOSIS
CXR: LV enlargement, dilated ascending aorta.
People with Marfan syndrome frequently have aortic insufficiency as well.
TREATMENT
Surgery or balloon valvuloplasty to treat aortic stenosis may worsen the insufficiency.
Aortic valve replacement is the only definitive therapy.
Mitral Stenosis
EPIDEMIOLOGY
Rare in children; usually a sequela of acute rheumatic fever.
Congenital forms are generally severe.
SIGNS AND SYMPTOMS
When symptomatic, dyspnea is the most common symptom.
Weak peripheral pulses with narrow pulse pressure.
An opening snap is heard on auscultation; also, a presystolic murmur may be heard.
Pulmonary venous congestion occurs, →:
CXR evidence of interstitial edema.
Hemoptysis from small bronchial vessel rupture.
TREATMENT
Balloon valvuloplasty
Surgical:
Commissurotomy
Valve replacement
Mitral Valve Prolapse
PATHOPHYSIOLOGY
Caused by thick and redundant valve leaflets that bulge into the mitral annulus.
EPIDEMIOLOGY
Usually occurs in older children and adolescents.
Has a familial component (autosomal dominant).
Nearly all patients with Marfan syndrome have it.
SIGNS AND SYMPTOMS
Auscultation: Midsystolic click and late systolic murmur.
Often asymptomatic with some history of palpitations and chest pain.
Coarctation of the aorta is associated with Turner syndrome.
TREATMENT
Management is symptomatic (eg, β blocker for chest pain).
OTHER CONGENITAL CARDIOVASCULAR DEFECTS
Coarctation of the Aorta
PATHOPHYSIOLOGY
Most commonly found in the juxtaductal position (where the ductus arteriosus joins the aorta).
Development of symptoms may correspond to the closure of the ductus arteriosus (the patent ductus provides additional room for blood to reach the postductal aorta).
The presence of ↓ pulses in the lower extremities is the clue for diagnosis of coarctation.
EPIDEMIOLOGY
More common in males than females (male-to-female ratio 2:1).
Association: Seen in one-third of patients with Turner syndrome.
Comparison of the right upper extremity blood pressures and pulse oximeter readings with the lower extremity should be performed with a possible diagnosis of coarctation.
SIGNS AND SYMPTOMS
Clinical Presentation of Symptomatic Infants
FTT, respiratory distress, and CHF develop in the first 2–3 months of life.
Lower extremity changes: ↓ pulses in the lower extremities.
Acidosis may develop as the lower body receives insufficient blood.
Usually, a murmur is heard over the left back.
Clinical Presentation of Asymptomatic Infants or Children
Normal growth and development.
Occasional complaint of leg weakness or pain after exertion.
↓ pulses in the lower extremities.
Upper-extremity HTN (or at least greater than in the lower extremities).
DIAGNOSIS
CXR: “3 sign,” dilated ascending aorta that displaces the superior vena cava to the right (see Figure 13-9).
TREATMENT
Resection of the coarctation segment with end-to-end anastomosis is the intervention of choice for initial treatment.
Allograft patch augmentation can also be used.
Catheter balloon dilation can be used:
Has a higher restenosis rate than surgery.
Has an ↑ risk of producing aortic aneurysms.
Balloon dilation is more frequently used when stenosis occurs at the surgical site of a primary reanastamosis.
Ebstein’s Anomaly
DEFINITION
Components of the defect (see Figure 13-10):
The tricuspid valve is displaced apically in the right ventricle.
The valve leaflets are redundant and plastered against the ventricular wall, often causing functional tricuspid atresia.
The right atrium is frequently the largest structure.
FIGURE 13-9. Coarctation of the aorta.
FIGURE 13-10. Ebstein’s anomaly.
EPIDEMIOLOGY
Without intervention:
CHF in first 6 months.
Nearly 50% mortality.
SIGNS AND SYMPTOMS
Growth and development can be normal depending on severity of the lesion.
Older patients usually complain of dyspnea, cyanosis, and palpitations.
Widely split S1, fixed split S2, variable S3 and S4 (characteristic triple or quadruple rhythm).
Holosystolic murmur at left lower sternal border.
Opening snap.
Cyanosis from atrial right-to-left shunt.
DIAGNOSIS
ECG: Right axis deviation, right atrial enlargement, RBBB; WPW is present in 20%.
CXR: Cardiomegaly (“balloon-shaped”) “wall-to-wall heart” in severely affected infants.
Echocardiogram is diagnostic.
TREATMENT
Intervention (87% do well):
Glenn procedure to ↑ pulmonary blood flow.
Severely affected infants may require aortopulmonary shunt.
Tricuspid valve replacement or reconstruction.
Right atrial reduction surgery.
Ablation of accessory conduction pathways.
Total Anomalous Pulmonary Venous Return (TAPVR)
The pulmonary veins bring the blood from the lungs to the right atrium (instead of the left atrium).
PATHOPHYSIOLOGY
See Figure 13-11A and B.
No communication exists between the pulmonary veins and the left atrium.
All pulmonary veins drain to a common vein.
The common vein drains into the:
Right superior vena cava (50%).
Coronary sinus or right atrium (20%).
Portal vein or inferior vena cava (20%).
Combination of the above types (10%).
An ASD is needed for survival.
EPIDEMIOLOGY
Dramatically more common in males (male-to-female ratio 4:1).
SIGNS AND SYMPTOMS/DIAGNOSIS/TREATMENT
Presence or absence of obstruction of pulmonary venous return changes the clinical presentation.
TAPVR with Obstruction
Obstruction → ↑ pulmonary artery pressure (and subsequent pulmonary edema) that ↑ pulmonary then right atrial and ventricular pressures. This causes a right-to-left shunt and resultant cyanosis.
Presents with early, severe respiratory distress and cyanosis, no murmur, and hepatomegaly.
CXR: Normal-size heart, pulmonary edema.
Echocardiogram is diagnostic.
Management: Baloon atrial septostomy or immediate corrective surgery.
TAPVR Without Obstruction
Free communication between right atrium and left atrium.
Large right-to-left shunt (“large ASD”).
Presents later during first year of life, with mild FTT, recurrent pulmonary infections, tachypnea, right heart failure, and rarely cyanosis.
CXR: Cardiomegaly, large PAs; ↑ pulmonary vascular markings (“snowman” or “figure eight” sign) is found in infants > 4 months old.
Management: Surgical movement of pulmonary veins to the left atrium.
Hypertrophic Obstructive Cardiomyopathy
Autosomal dominant 60%, sporadic 40%.
Sudden death: 4% to 6% incidence.
Asymmetrical septal hypertrophy or idiopathic hypertrophic subaortic stenosis (IHSS) is the most common form.
Outflow obstruction potentially caused by leaflet of mitral valve.
ECG: LVH and left atrial enlargement, large Q wave (indicates septal hypertrophy).
Echo: Asymmetrical septal hypertrophy, outflow obstruction (which predict the severity of disease).
FIGURE 13-11. Total anomalous pulmonary venous return.
A. Supracardiac view. B. Infracardiac view.
TREATMENT
Moderate restriction of physical activity.
β blocker or calcium channel blocker to improve filling.
Endocarditis prophylaxis.
