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For further information, see CMDT Part 10-12: Tetralogy of Fallot
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Essentials of Diagnosis
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Five features are characteristic:
Ventricular septal defect (VSD)
Concentric right ventricular hypertrophy (RVH)
Right ventricular (RV) outflow obstruction due to infundibular stenosis
Septal overriding of the aorta in half of patients
A right-sided aortic arch in 25%
Most adult patients with tetralogy of Fallot have been operated on, usually with an RV outflow patch and VSD closure; if patch overrides the pulmonary valve annulus, pulmonary regurgitation is common
Physical examination may be deceptive after classic tetralogy repair, with severe pulmonary valve regurgitation difficult to detect
Echocardiography/Doppler may underestimate significant pulmonary valve regurgitation; be wary if the RV is enlarged
Arrhythmias are common; periodic ambulatory monitoring is recommended
Serious arrhythmias and sudden death may occur if the QRS is wide or the RV becomes quite large, or both
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General Considerations
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If there is an associated atrial septal defect (ASD), the complex is called pentalogy of Fallot
Pulmonary valve stenosis may also be present, usually due to either a bicuspid pulmonary valve or RV outflow hypoplasia
The aorta can be enlarged and aortic regurgitation may occur
If > 50% of the aorta overrides into the RV outflow tract, the anatomy is referred to as a double outlet RV
Two vascular abnormalities are common
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Most adult patients in whom tetralogy of Fallot has been repaired are relatively asymptomatic unless right heart failure or arrhythmias occur
Physical examination should check both arms for any loss of pulse from a prior shunt procedure in infancy
Jugular venous pulsations may reveal
Right-sided arch has no consequence
The precordium may be active, often with persistent pulmonary outflow murmur
P2 may or may not be audible
Right-sided gallop may be heard
A residual VSD or aortic regurgitation murmur may be present
The insertion site of a prior Blalock or other shunt may create a stenotic area in the branch pulmonary artery (PA), resulting in a continuous murmur
Pulmonary arterial stenotic bruits may be best heard on the lateral chest wall
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ECG reveals
Chest radiograph shows
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