Congenital Heart Disease Flashcards
Congenital Heart Disease
An abnormality of formation or function present at or before birth
Cause of congenital heart diseases (3)
- some direct genetic
- 2% environmental
- rest multifactorial/uncertain
Example of genetic cause CHD (3)
- abnormal # of chromosomes i.e. Down syndrome
- monosomies (Turner’s)
- microdeletions (diGeorge)
Example of environmental cause of CHD (1+ 2+ 2)
- alcohol intake during pregnancy
- teratogens:
- viruses = rubella
- drugs = retinoic acid, alcohol
- maternal diseases = diabetes, lupus
When is the heart forming
Weeks 4-8
Cardiac structures essentially complete by 7-8 weeks of gestation
When does the heart begin beating
About day 28 (actually more like day 22)
When are genetic and environmental influences more important to development of CHD, when are pathogenic?
- 4-8 weeks for genet and environmental influences
- pathogenic mechanisms later
Pathogenesis of CHD
-development of cardiac malformation results from an injuring agent that acts during a critical time to produce the abnormal development = pathogenic mechanism
Simple lesions
Simple defects usually restricted to one abnormality such as ventricular septal defect or patent ductus arteriosus
Complex lesions
- several defects comprising the whole
- ex: tetralogy (4) of fallot
Tetralogy of fallot (4)
1) VSD
2) Sub-pulmonary stenosis
3) Aortic overide
4) RV hypertrophy
Most common congenital defect
-Bicuspid aortic valve (1%)
Situs
abnormal position/location of heart as whole in the body
Situs of different components of the heart
1) Atrial situs
2) Atrio-ventricular connections
3) Ventriculo-arterial connection
Heart failure-definition
A clinical syndrome characterized by symptoms resulting from heart disease
LV failure
When LV dysfunction results in fluid retention or exercise intolerance
LV dysfunction
Abnormality of relaxation (diastolic) or contraction (systolic)
Symptoms of congestive failure (6)
- Shortness of breath (alveolar edema)
- Abdominal bloating (ascites)
- Fluid accumulation in legs/face
- Diaphoresis/faints
- Difficulty feeding/growing in young
- Impaired exercise tolerance
Structural defects with congestive heart failure (2)
1) To much pulmonary blood flow
- ventricular septal defects
- patent ductus arteriosus
- atrioventricular septal defect
2) Reduced forward flow
- obstructive left heart lesions
Non-structural causes of CHF (3)
- myocardial failure
- circulatory volume overload (anemia)
- severe respiratory disease (pre-term with broncho-pulmonary dysplasia)
Signs of heart disease in infants
- Cyanosis = blue ting to skin
2. O2 sat 5 gm/L of desaturated jemoglobin
Causes of cyanotic lesions
- Transposition of the great arteries
- Tetralogy of Fallot
- Tricuspid valve abnormalities
- Total anomalous pulmonary venous drainage
- Pulmonary valve atersia
Questions for history -diagnosis CHD (10)
- Pregnancy hx/ family hx of CHD *including sudden death
- Feeding/growth
- Activity
- Color
- Breathing
- Wake/Sleep
- Faints/Spells
- Palpitations
- Exercise tolerance
- Chest pain
Physical examination -diagnosis CHD
- vital signs including BP 4 limbs
- work of breathing
- vascular congestion/liver/lungs/soft tissues
- cardiac activity/rhythm
- murmur(s) timing and quality
- cyanosis/clubbing
