Congenital Heart Disease in Children
Volume overload and pressure overload are subsets of
acyanotic congenital heart disease
TOF Tri. atresia
Decreased PBF
Tx of TOF?
Severe: urgent need surgery asap w prostaglandins to keep the PDA open LEss severe 4-6 months you can wait still need surgery Surgery is removing obstructive bundles and patch
least common septal defect, upper seputm, abnormal return R pulmonary veins
Sinus venosus ASD
ASD (atrial septal defect) more common with
boys
PSD
girls
Pressure overload Can be from transverse arch to iliac bifurcation 98% are below the origin of left subclavian artery M:F 2:1 Turner syndrome Bicuspid aortic valve 70%
Coarctation of the aorta
Septum grows towards the cushion and divides the atria, failure leads to ASD Desaturated blood mixes in the RA w/ fully saturated blood (L -> R) Increased oxy sat in RA
ASD pathophysiology
Predominant physiological load Most common is volume load d/t L to right shunt Pressure load is also common d/t ventricular outflow obstruction What type of lesion is this?
Acyanotic congenital lesions
Critical AS:LV failure Low output and pulmonary edema Sudden death can occur in severe LV outflow obstruction (murmur is heard in these pt) Mild/moderate = early systolic ejection click, no changes w/ respiration Severe is louder longer w thrill
Aortic stenosis
Acyanotic pressure overload 5% of CHD Bicuspid aortic valve in 1.5% pt M:F 3:1 Most common is valvular stenosis of the leaflets
Aortic stenosis Others: Subvalvar AS: discrete fibromuscular shelf Shone syndrome Supravalvar AS: least common Williams syndrome to right
The type of defect that causes sudden cardiac death in athletes
Aortic valve stenosis
Acyanotic w/ volume overload D/t failure of septal growth Includes isolated secundum, sinus venosus and PFO
Atrial septal defect
Atrioventricular Septal Defect: it exists Volume overload AKA ostium primum and AV canal endocardial cushion defect Failure of the septum to fuse with endocardial cushon Common in down syndrome trisomy 21
Atrioventricular Septal Defect
Tx of aortic valve stenosis
Balloon if bad Sub AS surgery High long-term risk of restenosis
trisomy 13, 18, 21 and turner syndrome 22q11 (DiGeorge) Genetic cardiomyopathies Heritable arrhythmias
CHD
HTN Pulse and BP different in arms and legs Legs 20/10 mm higher than normal Neonates may have acidosis or heart failure Cardiomegaly and pulmonary congestion are possible
COA Tx: close it but need PEG1 to maintain systemic flow
Tricuspid atresia, tetralogy of fallot and a single ventricle are examples of what
Cyanotic Congenital Lesions:Decreased Pulmonary Flow
In cyanosis from abnormal blood mixing the most common forms are HLHS, TAPVR, truncus arteriosus TAPVR = total anomalous pulmonary venous return
Cyanotic Congenital Lesions: Increased Pulmonary Flow
No obstruction of pulmonary blood flow Cyanosis d/t VA connections or mixing Most common form is TGA (transposition of the great arteries) in the subset of connections
Cyanotic Congenital Lesions: Increased Pulmonary Flow
Subset of diseases defined by systemic venous blood and oxygenated pulmonary venous blood mixing completely so that O2 sat is the same in PA and aorta
Cyanotic Congenital Lesions: Increased Pulmonary Flow
Cyanotic, increased PBF 5% of all CHD Normal venous and A-V connections but... Aorta arises from RV, pulmonary artery from LV Blue blood ejected out aorta to body Red blood re-directed back to lungs Systemic and pulmonary circulations in "parallel" Survival by mixing at PFO, PDA 50% also have VSD (more mixing)
D-Transposition of the great Arteries 5% HD, fairly common Aorta arises from RV and the pulmonary artery is from left ventricle and messes it all up Desat blood goes out the aorta to the body again and the oxygenated pulmonary blood goes back to the lungs Become parallel circuits Survival need mixing at ovale and ductus arteriosis otherwise they get no oxygenated blood Transposition and VSD which is good because you need the mixing at some level Only way this blood can get oxygen is mixing at PFO or PDA
Hypoxemia when the ductus closes Cyanosis, tachypnea, hemodynamic compromise Low arterial PO2 even with 100% oxygen Anomalous coronaries balloon atrial septostomy
DTGA Bedside procedure, slide wire across PFO and when the tip is in left atrium shoot air and it pumps a balloon then yank the wire through PFO and it rips open and stats go right up
PS AS Coarctation
Pressure overload
What do you see on chest x-ray with DTGA
Egg on a string
Cyanotic, increased PBF Underdeveloped left heart; stenosis/atresia of MV, AV RV maintains pulm + systemic circulations by PDA Pulm venous blood thru PFO/ASD Total mixing in right heart Usually inadequate maintenance of systemic circ Diagnosed prenatally or in first few days as PDA closes 5-15% associated with syndromes: Turner, trisomies, etc. May also have small aorta or coarctation
Hypoplastic Left Heart Syndrome
Can pulmonary stenosis, aortic stenosis and coarction be overcome?
If not severe then yes w/ hypertrophy If severe then no
TGA HLHS TAPVR Truncus
Increased PBF
Tx of pulmonary valve stenosis
Mod or severe balloon Often great results though the balloon may cause leakage Mild: just watch it
What are the most common causes of increased volume load in acyanotic congenital lesions?
Most common are left-to-right shunt: ASD, VSD, AVSD, PDA Atrial septal defect Venticular septal defect Aortic valve stenosis Patent ductus arteriosis
What are the most common causes of increased pressure load
Obstruction of normal flow PS, AS and coarctation Pulmonary stenosis Aortic stenosis
Cyanotic CHD that decreases pulmonary flow requires 2 things:
Obstruction to PBF Shunt from right to left (venous to systemic) PBF = TV, RV, PV?
What is the premature benign murmur in babies called?
PDA Patient ductus arteriosis
Bounding pulses Wide pulse pressure from runoff pressure from aorta to PA during diastole Distinctive continuous washing machine murmur
PDA: Manifestations, Diagnosis
Acyanotic volume overload This structure shunts blood right to left shunt from pulmonary arteries to the aorta Remains patent and forms a left to right shunt Common in premature babies
Patent Ductus Arteriosus
Deformed valve cusps cause incomplete opening Associated with Noonan, LEOPARD, Allagille syndromes Failure of development of three leaflets Or insufficient tissue resorption
Pulmonary Valve Stenosis Isolated valvar PS accounts for 7-10% of CHD May also have subvalvar or supravalvar PS
Severe causes RV failure, edema, exercise intolerance Mild causes pulmonary ejection click, RVH on ECG Moderate causes a later click, S2 and murmur peak Severe causes: Cyanosis, cardiomegaly, loud/long murmur RV systolic dysfunction
Pulmonary valve stenosis
Cyanotic CHD with increased pulmonary blood flow
TGA, TAPRV, truncus arteriosus, HLHS Total anomalous pulmonary venous return
Most common form of ASD; region of fossa ovalis Structurally normal AV valves Single or multiple; > 2cm likely symptomatic Females > males (3:1)
Secundum ASD
Asymptomatic typically Platypnea (dyspnea on standing) Found on exam: ejection click (pulmonary) Wide split and fixed S2 in all phases of respiration Systeolic ehection murmur (d/t increased outflow into pulm artery)
Secundum ASD:Clinical Manifestations
Severe obstruction causes immediate cyanosis Older pt squat to relieve the sx as it increases venous outflow Tet spells occur: Paroxysmal hypercyanotic: Infants, agitated, cyanotic, gasping, syncope, hypoxic blue spells, crying Loud and harsh murmur
TOF
Single arterial trunk supplies systemic, pulmonary, coronary circulations from both ventricles stenotic and/or regurgitant (leaky) As PVR drops, pulm circ increases, heart failure ensues Wide pulse pressure, bounding pulses Associated with DiGeorge syndrome Echo is diagnostic; good prognosis but mult surgeries
Truncus Arteriosus
Tx of VSD depends on the size of the hole: 30-50% small ones close (muscular 80% > membranous) Small usually uneventful Large ones can cause failure, lung infection, PVD and the large ones do not close probably need diuretics for the excess fluid Tx of the large ones?
Surgical closure if symptoms, FTT, PHTN, big shunt Transcatheter occlusion for muscular VSD Excellent outcomes; usually full recovery Risk of heart block
Cyanotic, decreased PBF Primary defect: anterior deviation of the infundibular septum Separates aortic/pulm outflow Obstruction to RV outflow (PS) Malalignment VSD Overriding aorta (dextroposition) Right ventricular hypertrophy
Tetralogy of Fallot
Cyanotic CHD with decreased pulmonary blood flow
Tetralogy of fallot Tricuspid atresia
Tx PDA
Usually don't close Small ones aren't too bad Large ones can cause HF Can cath or surgically close
When small asymptomatic When large: Harsh holocystolic mumur over LLSB Loud murmurs are good = small hole w/ a lot of pressure Less harsh murmur is bad S/S dyspnea, difficulty feeding, heart failure Develop over the first month of life
VSD: Clinical Manifestations
Acyanotic volume overload Most common malformation (25%) L to R at ventricle = increased oxygen in the RV ASD is the atrium, this is ventricle Increased flow Most commonly membranous in posterior position
Ventricular septal defect Can also be mid portion or apical (single or multiple towards bottom of heart)
Pulmonary veins drain to RH instead of heart = cyanosis, emergency Rare case where prostaglandin does not help TRUE SURGICAL EMERGENCY Increased PBF Total mixing
Total Anomalous Pulmonary Venous Return
How do you tx secundum ASD?
Transcatheter or surgical closure Low mortality in childhood Cath closure by occlusion best option
cyanotic, decreased pulmonary blood flow, no open connection b/t RA RV and the tricuspid is gone R -> L shunt at the PFO or ASD LV blood goes into aorta and across VSD
Tricuspid atresia
The 3 fetal shunts are
Venous system (ductus venosus) Heart (foramen ovale) Arterial system (ductus arteriosus)
What causes increased volume load
communication b/t systemic and pulmonary circulation hence pulmonary overcirculation AKA oxygenated blood goes back to the lungs
Decreased stats and pulmonary blood flow =
cyanotic
Decreased PBF and increased PBF are subsets of
cyanotic congenital heart disease
Most of RV output diverted away from lungs through (to descending thoracic aorta and placenta)
ductus arteriosus
supplies the ductus arteriosis and descending aorta to the placenta for oxygen
fetal right ventricle
Fetal heart preferentially delivers oxygen-saturated blood to metabolically active tissues
heart and brain
Sporadic, familial, holt-oram syndrome, 7% of CHD
isolated secundum asd
Causes of CHD?
multifactorial
common in infancy Usually hemodynamically insignificant 15-30% of adults; rarely requires treatment May be important with other underlying things Can increase risk of stroke if condition causing venous clotting in adult
patent foramen ovale
The most common major congenital heart defect is the
ventricular septal defect VSD 35% of lesions
ASD VSD PDA AVSD
volume overload