Congenital heart disease (2) Flashcards
Congenital heart disease: types
Patent Ductus Arteriosus
Overview
Overview:
- a form of congenital heart defect
- generally classed as ‘acyanotic’. However, uncorrected can eventually result in late cyanosis in the lower extremities, termed differential cynaosis.
- connection between the pulmonary trunk and descending aorta
- more common in premature babies, born at high altitude or maternal rubella infection in the first trimester
Congenital heart disease
Pstent ductus arteriosus
Features
Features:
- left subclavicular thrill
- continuous ‘machinery’ murmur
- large volume, bounding, collapsing pulse
- wide pulse pressure
- heaving apex beat
Management:
- indomethacin closes the connection in the majority of cases
- if associated with another congenital heart defect amenable to surgery then prostaglandin E1 is useful to keep the duct open until after surgical repair
Congenital heart disease
Patent ductus arteriosus
Right to left shunt
Eisenmengers syndrome
When the pressure rises in the right side can get a change to a right to left shunt
Referred to Eisenmengers syndrome
Get deoxygenated blood flowing to lower extremities
Results in cyanosis in the lower extremities
Congenital heart disease
Tetrology of Fallot
Tetralogy of Fallot (TOF) is the most common cause of cyanotic congenital heart disease*. It typically presents at around 1-2 months, although may not be picked up until the baby is 6 months old
Features
TOF is a result of anterior malalignment of the aorticopulmonary septum. The four characteristic features are:
- ventricular septal defect (VSD)
- right ventricular hypertrophy
- right ventricular outflow tract obstruction, pulmonary stenosis
- overriding aorta
Congenital heart disease
Tetrology of Fallot
The severity of the right ventricular outflow tract obstruction determines the degree of cyanosis and clinical severity
Other features
Other features:
- cyanosis
- causes a right-to-left shunt
- ejection systolic murmur due to pulmonary stenosis (the VSD doesn’t usually cause a murmur)
- a right-sided aortic arch is seen in 25% of patients
- chest x-ray shows a ‘boot-shaped’ heart, ECG shows right ventricular hypertrophy
Management
- surgical repair is often undertaken in two parts
- cyanotic episodes may be helped by beta-blockers to reduce infundibular spasm
*however, at birth transposition of the great arteries is the more common lesion as patients with TOF generally present at around 1-2 months
Congenital heart disease
Tetrology of Fallot
Diagnosis:
- Echocardiography (prenatally)
Treatment - Cardiac repair surgery (first year):
- septal defect closes
- right ventricular outflow tract enlarged
Fixing above two defects resolves:
- rv returns to normal
- O2 rich blood will now flow to the aorta
Congenital heart disease
Tetrology of Fallot
Summary
Boot shaped heart
