Patent Ductus Arteriosus vs Ventricular Septal Defect
Patent Ductus Arteriosus and Ventricular Septal Defect are easy to mix up on the boards. Here's a side-by-side comparison — presentation, workup, imaging, and first-line treatment — drawn from our full outlines.
Patent Ductus Arteriosus vs Ventricular Septal Defect at a glance
- Patent Ductus Arteriosus: Persistent fetal connection between aorta and pulmonary artery producing a continuous machinery murmur and L-to-R shunt.
- Ventricular Septal Defect: Opening in the interventricular septum causing a left-to-right shunt with a harsh holosystolic murmur at the LLSB.
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Side-by-side comparison
| Feature | Patent Ductus Arteriosus | Ventricular Septal Defect |
|---|---|---|
| At a glance | Persistent fetal connection between aorta and pulmonary artery producing a continuous machinery murmur and L-to-R shunt. | Opening in the interventricular septum causing a left-to-right shunt with a harsh holosystolic murmur at the LLSB. |
| Classic presentation | Continuous machinery murmur with wide pulse pressure and bounding pulses in a child; differential cyanosis is pathognomonic when shunt reversal develops.;… | Harsh, blowing holosystolic murmur with palpable thrill at the LLSB; intensity inversely related to defect size in many cases.; Small VSD: asymptomatic,… |
| Workup / key labs | BMP, CBC; Genetic evaluation if features suggest a syndrome (Down, rubella exposure history) | Basic labs are typically normal; BNP if HF symptoms |
| Imaging | Transthoracic echocardiography with color Doppler — diagnostic; visualizes the ductus, direction and velocity of shunt, and chamber size; ECG: normal if… | Transthoracic echocardiography with color Doppler — diagnostic; defines anatomy, size, shunt direction, chamber size, RV pressure, presence of AR (especially… |
| First-line treatment | Premature infants (hemodynamically significant PDA): supportive care first (fluid restriction, diuretics, optimize ventilation). Pharmacologic closure with… | Small, restrictive, asymptomatic VSD: observation; spontaneous closure is common in muscular and small perimembranous defects; Hemodynamically significant VSD… |
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