Common Cardiac Problems in Pediatric Practice

Dr. Pravin Asir Abraham.

DISCLAIMER: This lecture is based on

generalizations and common cases presented at the pediatrics dept, AMH.

There are many more CHDs than what I’ve listed and I hope you can use these principles to help you out with those.

Cardiac cases at AMH Newborn referrals- Cardiac murmurs. Cyanosis. Respiratory symptoms.

Pediatric referrals-Cardiac murmurs. Chest pain evaluation. Palpitation evaluation. Syncope evaluation. Evaluation of genetic syndromes. Pre-operative evaluation. Evaluating cardiac involvement in systemic

diseases.

NEWBORN REFERRALS

Fetal Circulation For the fetus the placenta is the

oxygenator so the lungs do little work RV & LV contribute equally to the

systemic circulation and pump against similar resistance

Shunts are necessary for survival ductus venosus (bypasses liver) foramen ovale (R→L atrial level shunt) ductus arteriosus (R→L arterial level shunt)

Transitional Circulation With first few breaths lungs expand

and serve as the oxygenator (and the placenta is removed from the circuit)

Foramen ovale functionally closes Ductus arteriosus usually closes

within first 1-2 days

Neonatal Circulation Pulmonary resistance (PVR) is high;

so initially RV pressure ~ LV pressure

RV pumps to pulmonary circulation and LV pumps to systemic circulation

By 6 weeks pulmonary resistance drops and LV becomes dominant

Normal Pediatric Circulation LV pressure is 4-5 x RV pressure

(this is feasible since RV pumps against lower resistance than LV)

RV is more compliant chamber than LV

Normal cardiac findings in newborns- HR range 100-180. Varying degrees of acrocyanosis. Maximal cardiac impulse at LLSB- RV

hyperactive. S2 may be single for first few days of

life. An ejection click representing

pulmonary hypertension heard in first hours of life.

Normal cardiac findings in newborns- contd. Pulmonary flow murmur-grade 1-2/6

systolic ejection murmur(innocent murmur)-characteristically radiates to sides and back of the chest. This prevalence and loudness increased in preterms.

Peripheral pulses are bounding due to lack of subcutaneous tissue.

Congenital Heart Disease (CHD)

Occurs in 0.5-1% of all live births Simple way to classify is:

L→R shuntsCyanotic CHD (R→L shunts)Obstructive lesions

L→R Shunts (“Acyanotic” CHD) Defects

1. VSD

2. PDA

3. ASD

4. AVSD (or complete atrioventricular canal)

May not be apparent in neonate due to high PVR (ie- bidirectional shunt)

L→R Shunts –General Points

PDA /VSD(5-10/15-20) Presents in infancy w/

heart failure, murmur, and poor growth

Left heart enlargement (LHE)

Transmits flow and pressure

ASD(5-10) Presents in childhood

w/ murmur or exercise intolerance (AVSD or 1o ASD presents earlier)

Right heart enlargement (RHE)

Transmits flow only

AVSD can present as either depending on size of ASD & VSD component

Increased PBF

Left Heart Overload

Right Heart Overload

Pulm vasc markings equal in

upper and lower zones

Cardiomegaly

Eisenmenger’s Syndrome A long standing L→R shunt will

eventually cause irreversible pulmonary vascular disease

This occurs sooner in unrepaired VSDs and PDAs (vs an ASD) because of the high pressure

Once the PVR gets very high the shunt reverses (ie- now R→L) and the patient becomes cyanotic

R→L Shunts (CCHD)

↑ PBF Truncus arteriosus Total anomalous

pulmvenous return (TAPVR)

Transposition of the great arteries (TGA)

↓ PBF Tetralogy of Fallot Tricuspid atresia Ebstein’s anomaly

• “Blue blood bypasses the lungs”• Degree of cyanosis varies• Classify based on pulmonary blood flow (PBF)

Please note: This is a generalization. In reality most of these defects can present with low or high PBF (eg- ToF with little PS acts more like a VSD with high PBF)

R→L Shunts

↑ PBF Presents more often

with heart failure (except TGA)

Pulmonary congestion worsens as neonatal PVR lowers

Sats can be 93-94% if there is high PBF

Equal pressures here too

There is unimpeded PBF; thus, extreme

pulmonary overcirculation.

R→L Shunts

↓ PBF Presents more often

with cyanosis See oligemic lung

fields Closure of PDA may

worsen cyanosis

Dynamic subvalvular obstruction here

causes “Tet spells”

Why are pressures

equal?

70%

70%

99%

99%

90%

60%

60%

99%

99%

70%

Pulmonary overcirculation Too little

PBF

Different amounts of PBF(Truncus vs ToF)

Obstructive Lesions

Ductal Dependent

1. Critical PS/AS(8-12/3-6)

2. Critical CoA/IAA(8-10/1)

3. HLHS Presents in CV shock at

2-3 days of age when PDA closes

+/- cyanosis Needs PGE1

Non-Ductal Dependent1. Mild-moderate AS2. Mild-moderate CoA3. Mild-moderate PS Presents in older

child w/ murmur, exercise intolerance, or HTN (in CoA)

Not cyanotic

Without a PDA there is no blood flow to the abdomen

and lower extremities.

(Blue blood is better than no blood.)

Ductal-DependentLesion

Physical Exam Heart sounds

Ejection click = AS or PS Mid-systolic click = MVP Loud S2 = Pulmonary HTN Single S2 = one semilunar valve

(truncus), anterior aorta (TGA), pulmonary HTN

Fixed, split S2 = ASD, PS Gallop (S3) – may be due to cardiac

dysfunction/ volume overload Muffled heart sounds and/or a rub =

pericardial effusion ± tamponade

COMMON PEDIATRIC REFERRALS

Innocent murmurs

Still’s murmur Classic innocent murmur Heard most commonly in young children (3-

5 yrs of age) but can be heard in all ages “Vibratory” low-frequency murmur often

heard along LSB and apex Positional – increases in intensity when pt is

in supine position Also louder in high output states (i.e.

dehydration, fever) Need to differentate from VSD

Innocent murmurs

Pulmonary flow murmur Often heard in older children and adolscents Soft SEM at ULSB, little radiation; normal

second heart sound Not positional Need to differentiate b/w mild PS and

especially an ASD Hint: ASD would have a fixed split second

heart sound

Innocent murmurs Venous hum

Often heard in toddlers, young children Low pitched continuous murmur often

heard best in infraclavicular area, normal heart sounds

Positional – diminishes or goes completely away when pt in supine position or with compression of jugular vein

Need to differentiate between a PDA

CHEST PAIN IN CHILDREN Idiopathic(12-45)-precordial

catch,mastalgia Costochondritis(9-22) Musculoskeletal trauma(21) Lung(15-21) Psychogenic(5-9) GI(4-7) Sickle cell crisis(2) Cardiac(0-4)

Cardiac pains Severe AS. Severe PS. Mitral Valve prolapse. HOCM. CAD(ALCAPA or kawasaki disease

sequelae) Cocaine abuse. Pericarditis-pericardiotomy

syndrome)/Myocarditis. Arrhythmias(WPW syndrome,LQT)

Palpitations in children

Syncope in children Vasovagal syncope- with prodrome-

dizziness, pallor, palpitation, nausea, diaphoresis, hyperventilation followed by LOC.

Orthostatic hypotension- No prodrome-light headedness.

CVOD. Cardiac causes- AS, PS, HOCM,

Myocardial dysfunction, arrhythmias(WPW, LQTS,RV dysplasia,SVT,VT, CHB,SSS)

Syndrome Associations

Down – AV canal and VSD Turner – CoA, AS Trisomies 13 and 18 – VSD, PDA Fetal alcohol – L→R shunts, ToF CHARGE – conotruncal (ToF,

truncus)

Hereditary Diseases Marfan (AD)– aortic root aneurysm ± dissection,

MVP, MR, AI HCM (AD) – outflow tract obstruction, arrhythmias Noonan (AD) – HCM, PS DMD/BMD (X-link) – DCM (>12 y.o.) Williams (AD) – supravalvar AS Tuberous sclerosis – rhabdomyoma Romano-Ward – AD LQTS Jervell & Lange-Nielsen – AR LQTS & deafness

Pre-operative evaluation Indications for prophylaxis

- High risk- prosthetic cardiac valve, previous bacterial endocarditis, CCHD, Surgically constructed systemic to pulmonary artery conduits.

- Moderate risk- Other CHD, Acquired Valvular disease, HCM, MVP with MR or thickened leaflets.

IE prophylaxis for DORE procedures Oral- Amoxicillin 50mg/kg 1 hr

before Sx. Inj- Ampicillin 50mg/kg IM or IV

within 30 minutes before Sx. Allergic to PCN- Cephalexin or

Cefadroxil 50mg/kg/ Azithromycin 15mg/kg 1 hr before Sx.

Allergic to PCN and unable orally-Clindamycin 20mg/kg or Cefazolin 25mg/kg within 30mts.

IE prophylaxis for GI and GU High risk-Ampi 50mg/kg IM or

IV(2g)+genta 1.5mg/kg within 30mts, Ampi 25mg/kg IM or IV 6hr(OR)Vanco 20mg/kg IV over 1-2 hr+genta 1mg/kg IM or IV.

Moderate risk-Amox 50mg/kg orally 1hr or ampi 50mg/kg IM or IV within 30mts(OR)Vanco 20mg/kg IV over 1-2hr.

Kawasaki Disease (KD) Now the #1 cause of acquired heart

disease.A systemic vasculitis (etiology-unknown)

Tests – CBC, CMP, CRP, ESR, EKG, ECHO

Rx – IVIG at 2g/kg and high-dose ASA Prognosis – Coronary artery

dilatation in 15-25% w/o IVIG and 4% w/ IVIG (if given within 10 days of fever onset). Risk of coronary thrombosis.

Kawasaki – Clinical criteria

Fever for at least 5 days AND 4 of the following 5 criteria:

Eyes - conjunctival injection (ie- no exudate) Lips & mouth - erythema, cracked lips,

strawberry tongue Hands & feet - edema and/or erythema Skin - polymorphous exanthem (ie- any rash) Unilateral, cervical lymphadenopathy

Rheumatic Fever

A post-infectious connective tissue disease Follows GAS pharyngitis by 3 weeks (vs.

nephritogenic strains of GAS) Injury by GAS antibodies cross-reacting with tissue Dx – JONES criteria (major and minor) Tests – Throat Cx, ASO titer, CRP, ESR, EKG, +/-

ECHO Rx – PCN x10 days and high-dose ASA or steroids 2o Prophylaxis – daily po PCN or monthly IM PCN

Rheumatic Fever – organs affected

1. Heart muscle & valves – myocarditis & endocarditis (pericarditis rare w/o the others)

2. Joints – polyarthritis

3. Brain – Sydenham’s Chorea (“milkmaid’s grip” or better yet, “motor impersistance”)

4. Skin – erythema marginatum (serpiginous border) due to vasculitis

5. Subcutaneous nodules – non-tender, mobile and on extensor surfaces

HEART-FELT THANKS