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8th March 2024
Clinical presentation
Signs and symptoms depend on the size and the length of the PDA (Table 1):
| Silent | Incidental and asymptomatic |
| Small | Qp:Qs <1.5
Asymptomatic with a flow murmur |
| Moderate | Qp:Qs between 1.5 to 2.2
May present with left or right heart failure Continuous machinery murmur at the first left intercostal space +/- thrill |
| Large | Qp:Qs > 2.2
A large PDA initially causes left ventricular overload If uncorrected, severe pulmonary hypertension develops (Eisenmenger physiology) The classic machinery murmur diminishes as pulmonary pressure increases Patients develop cyanosis and clubbing |
Table 1: Clinical presentation of different sized PDA
The complications of PDA include congestive cardiac failure, progressive pulmonary HTN and Eisenmenger syndrome; infective endocarditis, arrhythmias and ductus aneurysms.
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