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Paediatric Cardiology
Acyanotic CHD
Prof F F Takawira
Aetiology
• Chromosomal – Down syndrome, T13, T18
• Genetic syndromes (gene defects) – Velo-Cardio-facial (22 del)
• Genetic syndromes (undefined aetiology)
• Toxins – alcohol, warfarin
• Diabetes, SLE, rubella
Most cases without clear explanation
recurrence risk incr 3 - 4 fold
Fetal circulation
• Oxygenated blood from
placenta via umbilical vein
– 50% passes through liver
via portal veins
– 50% crosses ductus
venosus and continues up
inferior vena cava. IVC
also receives blood leaving
liver via hepatic veins and
returning from lower half
of body of fetus
Umbilical vein
Ductus venosus
Inferior vena cava
Fetal circulation
• Blood from Inferior vena cava:
– Most passes through foramen ovale to left atrium and left ventricle, ascending aorta and coronary circulation
– Small amount crosses tricuspid valve into right ventricle
Foramen ovale
Tricuspid valve
RA
LA
RV
LV
Fetal circulation
• Blood returning from head and neck enters right atrium via superior vena cava, is joined by coronary sinus blood and then enters right ventricle and pulmonary artery
Superior vena cava
RA
RV
PA
Fetal circulation
• 2/3 of combined ventricular output from right ventricle
• 85% of RV output goes via ductus arteriosus into descending aorta and 15% enters lungs via pulmonary arteries
• Blood in descending aorta travels via internal iliac and then umbilical arteries to placenta
Aorta
RV
Ductus arteriosus
PA
LV
RV
Ductus arteriosus
Aorta
PA
LV
Normal Transition
• Commencement of breathing
• Decrease in PVR
• Increase in SVR
• Closure of the three fetal systemic-pulmonary shunts:
– Ductus arteriosus
– Foramen ovale
– Ductus venosus
Age Related Changes
• Fetal communications
– ductus arteriosus
– foramen ovale
– ductus venosus
• Pulmonary vascular resistance
• Growth
• Importance of 6 week baby check
History
• Brainstorm: What are the key areas for paediatric history taking relating to heart conditions?
History
• Shortness of breath/tachypnoea
• Sweating
• Persistent cyanosis
• Feeding problems
• Growth problems
• Family history of CHD
Location of murmurs
•
pansystolic
ejection
truncated
continuous
Nature of Murmurs
decrescendo
mid diastolic flow
clicks, snaps, etc
Grades of murmurs • Grade 1
– scarcely audible • Grade 2
– Soft, easily audible • Grade 3
– loud, thrill absent • Grade 4
– loud, thrill present • Grade 5
– very loud, audible with stethoscope just off chest
• Grade 6 – audible without a stethoscope
Congenital Heart Disease
Acyanotic CHD
Approach to CHD
Cyanosis, SOBFTT, Sweats
Poor feeding, Chest defCCF, Cardiom, Congest
TGATruncusTAPVCHLHS
Increased PBF
CyanosisNo cardiom-usually
No CCFOligaemia
TOFTricuspid AtresPA, Critical PS
Ebstein
Decreased PBF
Cyanotic
ASCoarct
PSTR, MR
Normal PBF
Acyanotic, SOBFTT, Sweats
Poor feeding, Chest defCCF, Cardiomegaly, Conges
Lft-Rght shuntVSD
PDA; ASDAVSD
Increased PBF
Acyanotic
CHD
Growth Charts
Pectus Carinatum
Harrison’s sulcus
Box diagram of normal heart
Acyanotic Left to right shunts
• VSD
• PDA
• ASD
• AV septal defect (Endocardial Cushion defect)
Ventricular Septal Defect Physiology
Box diagram of ASD
Acyanotic Obstructive lesions
• Pulmonary stenosis
• Aortic stenosis
• Coarctation
Evaluation and Management of the Child with “Heart Disease”
Differentiate Normal from Abnormal
(dispelling doubts)
Decision regarding referral / Investigation
Ongoing Care
Features of an Innocent Murmur
• Normal peripheral examination
– “murmur in isolation”
• Typical features
– systolic
– ejection
– musical
– soft murmurs (grade 2/6 or less)
– change with body position
– varies with review / augmented by illness
Innocent murmurs
• Still’s
• Pulmonary flow murmur
• Carotid bruit
• Venous hum
Routine Investigation
• Chest X-Ray
– position
– contour
– pulmonary vascularity
• ECG
– “right sided” forces prominent
– include V3r / V4r
Advanced Investigation
• Echocardiography
• Cardiac catheterisation / Angiography
– diagnostic
– haemodynamic
– intervention
Clues to Congenital Heart Disease • Does the patient appear normal?
• Is the patient thriving?
• Is the patient cyanosed?
• Are there symptoms of heart failure? – Tachypnoea, poor feeding, exercise intolerance etc
• Are there other signs of heart disease? – Clubbing
– pulses / distribution / blood pressure
– hepatomegaly
– pericardial overactivity / thrill
– Murmur
• Is there any doubt?
Growth Charts
Summary
• Important and complex area
• Needs lots of practice
• Essential to know the basics - ie know what you are looking and listening for
• Essential to gain experience in CVS examination and looking at and interpreting ECG
• If in doubt => REFER!!